Properties of Ammonium Nitrate based fertilisers

The text is divided into three parts; Properties, Application and Safety of Ammonium Nitrate (AN) based fertilisers. In Properties, the structures and phase transitions of ammonium and potassium nitrate are reviewed. The consequences of phase transitions affect the proper use of fertilisers. Therefore the products must be stabilised against the volume changes and consequent loss of bulk density and hardness, formation of dust and finally caking of fertilisers. The effect of different stabilisers is discussed. Magnesium nitrate, ammonium sulphate and potassium nitrate are presented as a good compromise. In the Application part, the solid solutions in the systems (K+,NH4+)NO3- and (NH4+,K+)(Cl-,NO3-) are presented based on studies made with DSC and XRD. As there are clear limits for solute content in the solvent lattice, a number of disproportionation transitions exist in these process phases, e.g., N3 (solid solution isomorphous to NH4NO3-III) disproportionates to phases K3 (solid solution isomorphous to KNO3-III) and K2 (solid solution isomorphous to KNO3-II). In the crystallisation experiments, the formation of K3 depends upon temperature and the ratio K/(K+NH4). The formation of phases K3, N3, and K2 was modelled as a function of temperature and the mole ratios. In introducing chlorides, two distinct maxima for K3 were found. Confirmed with commercial potash samples, the variables affecting the reaction of potassium chloride with AN are the particle size, time, temperature, moisture content and amount of organic coating. The phase diagrams obtained by crystallisation studies were compared with a number of commercial fertilisers and, with regard to phase composition, the temperature and moisture content are critical when the formation and stability of solid solutions are considered. The temperature where the AN-based fertiliser is solidified affects the amount of compounds crystallised at that point. In addition, the temperature where the final moisture is evaporated affects the amount and type of solid solution formed at this temperature. The amount of remaining moisture affects the stability of the K3 phase. The K3 phase is dissolved by the moisture and recrystallised into the quantities of K3, which is stable at the temperature where the sample is kept. The remaining moisture should not be free; it should be bound as water in the final product. The temperatures during storage also affect the quantity of K3 phase. As presented in the figures, K3 phase is not stable at temperatu¬res below 30 °C. If the temperature is about 40 °C, the K3 phase can be formed due to the remaining moisture. In the Safety part, self-sustaining decomposition (SSD), oxidising and energetic properties of fertilisers are discussed. Based on the consequence analysis of SSD, early detection of decomposition in warehouses and proper temperature control in the manufacturing process is important. SSD and oxidising properties were found in compositions where K3 exists. It is assumed that potassium nitrate forms a solid matrix in which AN can decompose. The oxidising properties can be affected by the form of the product. Granular products are inherently less oxidising. Finally energetic properties are reviewed. The composition of the fertiliser has an importance based on theoretical calculations supported by experimental studies. Materials such as carbonates and sulphates act as diluents. An excess of ammonium ions acts as a fuel although this is debatable. Based on the experimental work, the physical properties have a major importance over the composition. A high bulk density is of key importance for detonation resistance.

Studies on "Sappe" disease of the silkworm, Bombyx mori : II. Effect of age of larvae on the manifestation of the disease

The effect of age of the larvae on the manifestation of the "Sappe" disease of the silkworm by oral inoculation of different pathogens, viz., Aerobacter cloacae, Pseudomonas boreopolis, Escherichia freundii, Achromobacter delmarvae, A. Superficialis, Pseudomonas ovalis, and Staphylococcus albus was tested. It was found that the reaction of the larva to the pathogen was influenced by its age. Some, e.g., Escherichia freundii, were more lethal when introduced at early stages whereas certain others, e.g., Aerobacter cloacae and Staphylococcus albus, caused maximum damage when invading older larvae. Irrespective of the age of infection, death of the worms mainly occurred during molting and before spinning. The studies also indicated that growth and mortality of the larvae were affected differentially by the pathogens.

Experimental investigation of catalytic and non-catalytic surface reactions on SiO2 thin films with shock heated oxygen gas

The present study is to investigate the interaction of strong shock heated oxygen on the surface of SiO2 thin film. The thermally excited oxygen undergoes a three-body recombination reaction on the surface of silicon dioxide film. The different oxidation states of silicon species on the surface of the shock-exposed SiO2 film are discussed based on X-ray Photoelectron Spectroscopy (XPS) results. The surface morphology of the shock wave induced damage at the cross section of SiO2 film and structure modification of these materials are analyzed using scanning electron microscopy and ion microscopy. Whether the surface reaction of oxygen on SiO2 film is catalytic or non-catalytic is discussed in this paper.

Amide-catalysed isomerisation of 5,6-dihydroisoquinolines: a novel synthesis of 1,2-dihydroisoquinolines

Knoevenagel condensation of 2-acylcyclohexanones or 2-ethoxycarbonylcyclohexanone with either cyanoacetamide or malononitrile followed by silver salt alkylation gave the 5,6,7,8-tetrahydroisoquinolines (3a–i). Chromic acid oxidation of the 5,6,7,8-tetrahydroisoquinolines (3a–i) to the corresponding tetralones (4a–i) followed by sodium borohydride reduction and p-toluenesulphonic acid-catalysed dehydration of the resulting alcohols (5a–i) gave the 5,6-dihydroisoquinolines (6a–i). Reaction of 5,6-dihydroisoquinolines (6a–g) with potassium amide in liquid ammonia gave a mixture of the 1,3-dihydroisoquinolines (7a–g) and the isoquinolines (8a–g). The C-1 unsubstituted 1,2-dihydroisoquinoline (7c) was found to be very unstable. In the case of the 5,6-dihydroisoquinolines (6h and 6i), reaction of potassium amide in liquid ammonia resulted in a mixture of 1-aminoisoquinoline (9) and the isoquinolines (8h and 8i). All the above compounds have been characterised by spectral data. A probable pathway for the formation of the 1,2-dihydroisoquinolines (7a–g) and the isoquinolines (8a–i) is suggested.

Studies of phosphazenes. 12. Reactions of N4P4Cl8 with dibenzylamine- isolation of an unusual "bicyclic" phosphazene, N4P4[N(CH2Ph)2]6(NCH2Ph)

Octachlorocyclotetraphosphazene, N4P4CIa, reacts with dibenzylamine to give the chloro(dibenzy1amino) derivatives, N4P,C18,[N(CH2Ph)2],,, n = 1, 2 (two isomers), and 4 (three isomers). Nongeminal structures have been assigned to these compounds on the basis of ‘H and jlP NMR spectra. The presence of at least two tris(dibenzylamin0) derivatives in some reaction mixtures is also inferred from NMR spectra. Steric effects become important at the tetrakis stage of chlorine replacement, and further substitution by dibenzylamine to give monocyclic tetrameric derivatives does not occur. A “bicyclic” phosphazene, N4P4[N(CH2Ph)2]6(NCHzPh)is, obtained from the reaction of N4P4Claw ith an excess of dibenzylamine in boiling methyl cyanide. The formation of this derivative and its spectroscopic data are discussed.

Preparation, Characterisation and Thermal Properties of Hydrazinium Magnesium Sulfate

Hydrazinium magnesium sulfate, (N2H5)2Mg(SO4)2, has been prepared by dissolving magnesium powder in a solution of ammonium sulfate in hydrazine hydrate, by the reaction of ammonium magnesium sulfate with hydrazine hydrate, and by the cocrystallisation of dihydrazinium sulfate and magnesium sulfate. The product has been characterized by chemical analysis and infrared spectra. Thermal analysis of (N2H5)2Mg(SO4)2 by TG and DTA show exothermic decomposition at 302°C giving Mg(N2H4)SO4 as an intermediate and an endother-mic decomposition at 504°C producing MgSO4.

A new approach to thermochemical calculations of condensed fuel-oxidizer mixtures

A simple method of calculating the elemental stoichiometric coefficient, φe has been developed, which can easily be applied to multicomponent fuel-oxidizer compositions. The method correctly predicts whether a mixture is fuel lean, fuel rich, or stoichiometrically balanced. The total composition of oxidizing (or reducing) elements of the mixture appears to be related to the thermochemistry of the system. For the reaction of ammonium perchlorate and an organic fuel the heat of reaction varies linearly with the total composition of oxidizing elements. The physical significance of such a correlation based on thermochemical reasoning is highlighted in the paper.

Hydrolysis of sphingomyelin to ceramide with hydrofluoric acid

Sphingomyelin was hydrolyzed to ceramide near quantitatively on treatment with 40% HF at 40°C for 72 hr. The reaction of sphingomyelin with HF is much slower than phosphoglycerides. HF treatment did not alter either the fatty acid composition or the stereochemical configuration of the sphingosine moiety of ceramide formed.

A new mode of ring cleavage of 2,3-dihydroxybenzoic acid in Tecoma stans (L.). Partial purification and properties of 2,3-dihydroxybenzoate 2,3-oxygenase.

2,3-Dihydroxybenzoic acid has been shown to be oxidized via the 3-oxoadipate pathway in the leaves of Tecoma stans. The formation of 2-carboxy-cis,cis-muconic acid, a muconolactone, 3-oxoadipic acid and carbon dioxide during its metabolism has been demonstrated using an extract of Tecoma leaves. The first reaction of the pathway, viz., the conversion of 2,3-dihydroxybenzoate to 2-carboxy-cis,cis-muconic acid has been shown to be catalysed by an enzyme designated as 2,3-dihydroxybenzoate 2,3-oxygenase. The enzyme has been partially purified and a few of its properties studied. The enzyme is very labile with a half-life of 3--4 h. It is maximally active with 2,3-dihydroxybenzoate as the substrate and does not exhibit any activity with catechol, 4-methyl catechol, 3,4-dihydroxybenzoic acid, etc. However, 2,3-dihydroxy-p-toluate and 2,3-dihydroxy-p-cumate are also oxidized by the enzyme by about 38% and 28% respectively, compared to 2,3-dihydroxybenzoate. Sulfhydryl reagents inhibit the enzyme reaction and the inhibition can be prevented by preincubation of the enzyme with the substrate. Substrate also affords protection to the enzyme against thermal inactivation. Sulfhydryl compounds strongly inhibit the reaction and the inhibition cannot be prevented by preincubation of the enzyme with its substrates. Data on the effect of metal ions as well as metal chelating agents suggest that copper is the metal cofactor of the enzyme. Evidence is presented which suggests that iron may not be participating in the overall catalytic mechanism.

Bromination of Intermolecular Chelate Linkage Isomers of 3-Oximino-4,9-Dimethyl (or 4,7,9-Trimethyl)-5,8-Diazadodeca-4,8-Diene-2,11-Dionato Nickel(II)

The reaction of the title complexes (FIG. 1) with N-bromosuccinimide or bromine in chloroform yields isomeric bromo complexes on substitution of the γ-CH carbon proton by bromine. The brominated products have been characterised by ir, pmr, electronic absorption spectra, conductivity and magnetic susceptibility measurements. The linkage isomerisation of the brominated products in chloroform has been shown to depend on the diamine residue.

Studies of phosphazenes. Part I. Reactions of octachlorocyclotetraphosphazatetraene with ethylamine

The reaction of octachlorocyclotetraphosphazatetraene, N4P4Cl8, with ethylamine has been investigated. Seven derivatives, N4P4Cl8–n(NHEt)n[n= 1, 2 (two isomers), 3, 4 (two isomers), and 8] have been isolated and their structures established by 1H and 31P n.m.r. spectroscopy. A non-geminal chlorine atom replacement scheme is observed. Attempts to prepare penta- or hexa-ethylamino derivatives were unsuccessful: only sticky, non-crystalline resins were obtained from 1 : 10 or 1 : 12 reactions. The preparation and n.m.r. spectroscopic data of mixed ethylamino(methoxy)-derivatives. N4P4(NHEt)–8-n(OMe)n[n= 6, 4 (two isomers)], and an ethylamino-(dimethylamino)-derivative, N4P4(NHEt)2(NMe2)6, are generally consistent with the proposed structures. The reaction pattern is discussed.

Kinetics of formalization of poly(vinyl acetate)

Kinetic information on the formation of poly(vinyl formal) by the reaction of poly(vinyl acetate) and formaldehyde in presence of aqueous acid has been derived from the spectroscopic analysis of polymer samples after different periods of reaction. The hydroxyl content of poly(vinyl formal) is found to be nearly independent of reaction time and only slightly affected by temperature while the fall of acetate content and the increase in formal content are most rapid in the initial period and are largely influenced by temperature. The rate expression formulated on the assumption that the formalization reaction is of first order with respect to both poly(vinyl acetate) and formaldehyde explains the observed variation of polymer composition with reaction time. The activation energy for the reaction is found to be 17.3 kcal/mol.

Direct Synthesis of Functionalized Unsymmetrical beta-Sulfonamido Disulfides by Tetrathiomolybdate Mediated Aziridine Ring-Opening Reactions

Direct synthesis of unsymmetrical beta-sulfonamido disulfides by ring-opening of aziridines by using benzyltriethyl-ammonium tetrathiomolybdate 1 as a sulfur transfer reagent in the presence of symmetrical disulfides as thiol equivalents has been reported. Reaction of benzyl and alkyl disulfides gave unsymmetrical beta-sulfonamido disulfides as the only product in very good yields. From the Study, it has been observed that aryl disulfides containing p-NO2, p-Cl, and p-CN led to the formation of the corresponding beta-aminosulfides as the exclusive products. However, un-substituted aryl disulfides and the one containing electron-donating substituents (p-Me) provide a mixture of beta-sulfonamido mono- and disulfides as the products.

Synthesis, X-ray structure and properties of [Ru2O(MeCN)4(O2CMe)2(PPh3)2](ClO4)2

The diruthenium(III) complex [{(PPh3)(MeCN)2Ru}2(μ-O)(μ-O2CMe)2](ClO4)2 (1) has been prepared from Ru2O(O2CMe)4(PPh3)2, which is obtained from a reaction of Ru2Cl(O2CMe)4 and PPh3 in MeCN. The crystal structure of 1 was determined by X-ray studies and the complex has an {Ru2(μ-O)(μ-O2CMe)22+} core and the facial sites on each metal centre are occupied by two MeCN and one PPh3 ligands. The Ru—b. Ru and Ru—Ooxo distances and Ru—O—Ru angle are 3.240(1), 1.866(4) Å and 120.6(2)°, respectively. The cis and trans Ru—N distances in 1 are 2.040(6) and 2.116(5) Å, respectively. The visible spectral band in 1 is observed at 574 nm (var epsilon, 10,800 M−1 cm−1). The 1H NMR spectrum of the diamagnetic complex 1 in CD3CN is in agreement with the X-ray structure.

The genome packaging machinery of dsDNA bacteriophage PRD1

Viral genomes are encapsidated within protective protein shells. This encapsidation can be achieved either by a co-condensation reaction of the nucleic acid and coat proteins, or by first forming empty viral particles which are subsequently packaged with nucleic acid, the latter mechanism being typical for many dsDNA bacteriophages. Bacteriophage PRD1 is an icosahedral, non-tailed dsDNA virus that has an internal lipid membrane, the hallmark of the Tectiviridae family. Although PRD1 has been known to assemble empty particles into which the genome is subsequently packaged, the mechanism for this has been unknown, and there has been no evidence for a separate packaging vertex, similar to the portal structures used for packaging in the tailed bacteriophages and herpesviruses. In this study, a unique DNA packaging vertex was identified for PRD1, containing the packaging ATPase P9, packaging factor P6 and two small membrane proteins, P20 and P22, extending the packaging vertex to the internal membrane. Lack of small membrane protein P20 was shown to totally abolish packaging, making it an essential part of the PRD1 packaging mechanism. The minor capsid proteins P6 was shown to be an important packaging factor, its absence leading to greatly reduced packaging efficiency. An in vitro DNA packaging mechanism consisting of recombinant packaging ATPase P9, empty procapsids and mutant PRD1 DNA with a LacZ-insert was developed for the analysis of PRD1 packaging, the first such system ever for a virus containing an internal membrane. A new tectiviral sequence, a linear plasmid called pBClin15, was identified in Bacillus cereus, providing material for sequence analysis of the tectiviruses. Analysis of PRD1 P9 and other putative tectiviral ATPase sequences revealed several conserved sequence motifs, among them a new tectiviral packaging ATPase motif. Mutagenesis studies on PRD1 P9 were used to confirm the significance of the motifs. P9-type putative ATPase sequences carrying a similar sequence motif were identified in several other membrane containing dsDNA viruses of bacterial, archaeal and eukaryotic hosts, suggesting that these viruses may have similar packaging mechanisms. Interestingly, almost the same set of viruses that were found to have similar putative packaging ATPases had earlier been found to share similar coat protein folds and capsid structures, and a common origin for these viruses had been suggested. The finding in this study of similar packaging proteins further supports the idea that these viruses are descendants of a common ancestor.