Chemical effects in commercial and laboratory mixtures of ‘reactive’ phosphate rock and acidulated fertilisers

The chemical analyses of different size fractions of a variety of commerical and laboratory prepared samples of partially acidulated phophate rocks and mixtures of reactive phosphate rock and single superphosphate (called LONGLIFE in New Zealand) have been studied. Whereas only minor chemical segregation effects have been observed for partially acidulated products quite a large bias has been established for LONGLIFE materials, and more especially commercial samples, where larger proportions of phosphate rock were found in the lower size fractions. This inhomogeneity was considered to arise from poor mixing of components and subsequent inconsistent granulation; more stringent rejection criteria for undersize material would greatly assist in improving the product quality. Chemical deactivation of the phosphate rock residue in LONGLIFE materials was also observed; this can be partially explained by a selective reaction of the reactive phosphate rock component with acid still present at the time of mixing with the single superphosphate component.     

Critical solution point and chain dimension of branched-polystyrene solutions

Summary Critical solution point and chain dimension were measured for branched polystyrene(BPS) in solution as a function of molecular weight(M) and compared with those for linear polystyrene(LPS). The critical concentration _c of BPS was quite different from that of LPS at a fixed M, but the same at a fixed overlap-concentration ^*, i.e., plots of _c vs. ^* fall on a single straight line for both BPS and LPS (gf_c ^*). Reduced critical temperature _c defined by gt_c=(–T_c)/ [T_c: critical temperature, : the -temperature] was related to _c as _{c c} ² for BPS, whereas _{c c} for LPS.     

Effects of crystallinity and supermolecular formations on the interfacial shear strength and adhesion in GF/PP composites

Aim of this study was to screen the morphological effects on the interfacial shear strength (i) in glass fibre (GF) reinforced isotactic polypropylene (iPP) model composites. i was determined by a modified single fibre pull-out technique. It was established that the relation between i (5–6 MPa) and the yield stress of the iPP (y30 MPa) is at about 1:6 and that the i values were not influenced by the mophological superstructure set under isothermal crystallization conditions. Increased i was only observed when specimens were produced non-isothermally, by quenching (i9 MPa). This improvement could not be related to thermal shrinkage stresses. The enhancement in i was attributed to better wetting and improved adhesion due to the enlarged amorphous PP (aPP)-phase. A schematic adhesion model considering the wetting behaviour of aPP and iPP was proposed.     

Effect of amounts and sequence of additions of urea and water on hydrolysis of surface-applied granular urea in unsaturated soils

The hydrolysis of surface-applied granular urea ( 15 mg of urea/particle) in 14 unsaturated soils as influenced by the amounts and the sequence of additions of urea and water and studied using open and covered soil column systems was in the following order: well-mixed surface-applied surface-applied surface-applied urea, granular urea, granular urea, granular urea, water added > water added > water added water added before, after, before, before, no drying no drying no drying drying The retarded hydrolysis' of surface-applied granular urea is attributed to retarded soil urease activity. Under the nondrying and drying conditions, the positive effect of increasing amounts of added water on the hydrolysis was less apparent when water was added 24–48 hours before than when it was added immediately after surface application of granular urea. When an increasing number of urea granules were evenly placed on a finite surface of unsaturated soil, the rate of urea application (quantity factor) increased but the percentage of urea hydrolyzed remained practically unchanged. These results suggest that it is necessary to consider effective urea concentration and effective urease activity for adequate understanding of in situ hydrolysis of broadcast fertilizer urea in unsaturated soil.     

Studies concerning charged nickel hydroxide electrodes IV. Reversible potentials in LiOH,NaOH, RbOH and CsOH

The variation of reversible potential E_r with log a_moh and has been studied for several nickel hydroxide/oxyhydroxide couples in various alkali hydroxides. Both activated and deactivated -phase couples show only a small dependence ofE _r with log_moh (or where known) in LiOH, NaOH, RbOH and CsOH electrolytes. The change in MOH content on oxidation/reduction is found to be about 0.1 mol MOH per two-electron transfer and is the same as found previously in KOH. These results confirm that the bulk oxidized -phase lattice is devoid of alkali cation although a small quantity may be adsorbed by the surface. On the other hand both activated and deactivated /-phase couples show a marked dependence of 0.45 mol MOH per two-electron transfer in LiOH, NaOH and RbOH (at concentrations > 0.5 m), also in good agreement with earlier data for KOH. On the basis of these results a general stoichiometry can be inferred for the -phase, namely M_0.32NiO₂ · 0.7H₂O where M=Li⁺, Na⁺, K⁺ or Rb⁺. Measurements imply that the Cs⁺ ion or the Rb⁺ ion at low concentration (<0.5 m) do not enter the interlayer structure of the -phase. This behaviour is thought to be related to the low Rb-O and Cs-O bond strengths afforded by the -phase structure.     

Silphinene Sesquiterpenes as Model Insect Antifeedants

Silphinene sesquiterpenes are established chrysomelid antifeedants. In this work, nine silphinene analogs, 11-acetoxy-5-angeloyloxysilphinen-3-one (1), 11-acetoxy-5-tigloyloxysilphinen-3-one (2), 11-acetoxy-5-iso- butyryloxysilphinen-3-one (3), 11-hydroxy-5-angeloyloxysilphinen-3-one (4), 11,5-dihydroxysilphinen-3-one (5), 11,5-diacetoxysilphinen-3-one (6), 5,11-diisobutyryloxysilphinen-3-one (7), silphinen-3,5,11-trione (8), and O-methyl-5-epicantabrenolic acid methyl ester (10), and a presilphiperfolane sesquiterpene (9) were tested against several divergent insect species, including the lepidopteran Spodoptera littoralis, the chrysomelid Leptinotarsa decemlineata, and five aphid species, and their antifeedant effects were compared with those of picrotoxinin, a GABA-antagonist, and thymol, an allosteric modulator for insect GABA receptors. All insects tested responded to at least one silphinene analog and/or GABA antagonist. Compound 3 and thymol were effective antifeedants against all species tested except S. littoralis, with varying potencies according to their feeding ecologies. The toxicity of these compounds was species-dependent and did not correlate with their antifeedant effect.     

Effects of partial acidulation on chemical and mineralogical characteristics of residual phosphate rocks

Original phosphate rocks (PR) and water insoluble residues (WIR) from mixtures of reactive PRs and single superphosphate, known commercially as longlife single superphosphate (LLSSP), and from partially acidulated PRs (PAPR), were compared in terms of their elemental content, chemical reactivity as indicated by the apatite unit cell a dimension and solubility. Phosphate rock reactivity is known to be inversely related to the a dimension. Partial acidulation (20%) with commercial grade phosphoric acid resulted in an increase in aluminium (Al), iron (Fe) and fluoride (F) concentrations in the WIRs. The apatite a dimensions of WIRs from LLSSPs were greater than those of the respective original North Carolina (NC), Khouribga (KR), Jordan (JR), Sechura (SE) and Arad (AR) PRs added to single superphosphate (SSP), made from Nauru PR (NR)) to produce the LLSSPs. This was attributed to the presence of the less reactive NR in the WIRs left-over from the SSP. Partial acidulation with phosphoric acid increased the apatite a dimensions of NC and ElHassa (EH) PRs. The increase in apatite a dimension of NC and EH was probably due to selective dissolution of a more reactive fraction of the PRs during partial acidulation. Changes in the apatite a dimension following partial acidulation with phosphoric acid were not significant for the other PRs studied, e.g. Gafsa (GF), KR and AR, although differential X-ray diffractograms (DXRD) indicated that the material dissolved during partial acidulation was more reactive than the WIRs and the original PRs. The apatite a dimension of NC PR was not affected by pretreatment with 2% or 4% citric acid (CTA). The contrasting response in a of NC PR to acidulation with phosphoric and citric acids may be related to differences in the strength of these acids, and/or to the differing environments under which the reactions took place.The 2% CTA and formic acid (FMA) solubilities of the WIRs from LLSSPs and PAPRs were markedly lower than those of the original PRs. This reduction in solubility of PRs following partial acidulation was probably related to changes in mineralogical and chemical composition of the WIRs as indicated by the increases in apatite a dimension of some residual PRs and shifts in peak positions in DXRD, to increases in the concentrations of Fe, Al and F compounds, and to coating effects of PR particles by Fe, Al and F compounds. This, in turn, may reduce the agronomic value of the residual PR component of PAPR and LLSSP fertilizers, particularly over the short-term.The solubility of residual PRs following pretreatment with 2% or 4% CTA was slightly lower than that of the original PRs. The pretreatment caused no significant change in the apatite a dimension of NC PR. The complexing effects of CTA and its lack of Fe and Al impurities may have prevented the formation of Fe, Al and F compounds. The effect of citric acid on PR reactivity is thus quite different from that of the mineral acids used to prepare LLSSPs and PAPRs.     

Additional male mediterranean fruitfly (Ceratitis capitata wied.) Attractants from Angelica seed oil (Angelica archangelica L.)

Two sesquiterpene hydrocarbons, -copaene and -ylangene, were isolated from bioactive fractions of angelica seed oil and were shown by field bioassays to be attractive to the male Mediterranean fruit fly. Their relative attractiveness, compared with the(+)-and (–)--copaene enantiomers, are: (+)--copaene>angelica -copaene>angelica -ylangene>(–)--copaene. The enantiomer ratios for the two compounds are: -copaene, 61.4% (+), 38.6% (–); -ylangene, 91.9% (+), 8.1% (–).trans--Bergamotene was also isolated from the same fractions, but in sufficient quantity for bioassay [enantiomer ratio: 95.7% (+), 4.3% (–)].     

Study of the β — α solid-solid transition of isotactic polypropylene by synchrotron radiation

Synopsis The transformation of the -modification into -modification in isotactic polypropylene was investigated by WAXS, DSC and dilatometric methods. The temperature and time dependent WAXS spectra were made by using high-intensity synchrotron radiation. The - transformation was followed by short time exposures. The transformation of the -modification was found to act toward the increase in the total crystallinity.     

Dewatering deposits formed in purifying effluent from refractory factories by vacuum filtration

Conclusions The residue formed from effluent contaminated with chamotte dust, with coagulation and without coagulation, is thoroughly dewatered on vacuum equipment with concentrations of more than 700 kg/m³ of suspended particles in the residue.Residues obtained from effluent contaminated with mixtures of chamotte and clay dust in the ratio 41, 11, and 14 are dewatered less effectively than chamotte residues. The residue from a mixture of chamotte and clay 41 is dewatered with a minimum concentration of 809 kg/m³; the residue from the mixture of chamotte and clay 11 can be satisfactorily dewatered only with a high vacuum (640 mm Hg) and with a filter cycle time longer than that used in existing equipment. With a filter cycle of 30 min the thickness of the skin of uncoagulated residue was 13 mm. The coagulated residue from a mixture of clay and chamotte 11 even after 14 days holding had too low a concentration, and in practice cannot be dewatered on a vacuum filter. The residue from mixtures of 14 chamotte and clay is dewatered very ineffectively. The thickness of the cake with a filter cycle time of 20 min for uncoagulated residue was only 4 mm.Translated from Ogneupory, No. 6, pp. 17–20, June, 1970.     

13C NMR spin-lattice relaxation in solid poly(methyl methacrylate)

Summary ¹³C spin-lattice relaxation rates R₁ in samples of solid PMMA have been measured with CP MAS NMR. Isotactic, atactic, syndiotactic, and the 12 i-s PMMA complex were measured, along with atactic samples containing bisdioxan or the monomer as a plasticizer. The reorientation of the -methyl protons is the dominant relaxation source for the methylene, -methyl and quarternary carbon nuclei. Increased mobility of the polymer in the presence of a plasticizer is not reflected in significant changes in R₁.Presented at the 22nd Microsymposium, Characterization of Structure and Dynamics of Macromolecular Systems by NMR Methods, Prague, July 20–23, 1981     

Available nitrogen in soils and its determination by the ‘Nmin-method’ and by electroultrafiltration (EUF)

Excess nitrogen fertilizer rates are an environmental hazard. To avoid excess rates, the level of available nitrogen in the soil must be known and considered for assessing the nitrogen fertilizer rate. In arable soils nitrate and exchangeable ammonium in the rooting depth of a crop are directly available to plant roots. These two nitrogen forms are recovered with the Nmin method and they are considered in assessing the nitrogen fertilizer rate for arable crops.Besides nitrate and ammonium recovered by the Nmin method from soil samples taken in early spring, a considerable amount of organic soil nitrogen may be mineralized during the growth period and contribute to crop nutrition. The nitrogen mineralization potential can be determined in incubation tests. The absolute quantities of mineralized nitrogen thus obtained, however, are much higher than the mineralization rates under field conditions. It is for this reason that incubation tests have not obtained a major importance for assessing nitrogen fertilizer rates.With the electro-ultrafiltration (EUF) method nitrate, ammonium, and a minor portion of organic soil nitrogen are extracted from a soil suspension. There is experimental evidence that this organic nitrogen (=Norg) is easily mineralizable. Based on field experiments with cereals and maize formulae were established by which the nitrogen fertilizer rate can be calculated. In these formulae nitrate, ammonium and organic nitrogen extracted by EUF are considered.Advantages and drawbacks of the Nmin method and EUF method are discussed.     

Sex pheromone evidence for two distinct taxa withinGraphania mutans (Walker)

The sex pheromones of two populations ofGraphania mutans (Walker) were analyzed. Females from an Auckland population produced (Z)-9-tetradecenol (Z9-14OH), (Z)-9-tetradecenyl acetate (Z9-14OAc), (Z)-7-tetradecenol (Z7-14OH) and (Z)-7-tetradecenyl acetate (Z7-14OAc), while females from a Lincoln population produced these four compounds and a large amount of (Z)-9-tetradecenal (Z9-14Ald). Significant differences, paralleling the difference between females, were observed when the responses of males of both populations to the above and other related compounds were tested by electroantennogram, field-trapping, and wind-tunnel bioassays. The most distinct difference was observed in the wind tunnel. Males from both taxa flew upwind and touched pheromone sources containing sex pheromone extract of females of their own taxon, but either did not initiate upwind flight or arrested upwind flight shortly after taking flight in response to extract from females of the other taxon. The difference between the pheromone systems of the two populations is probably due to the presence and importance of Z9-14Ald in the pheromone blend of the Lincoln population. Thus the addition of a relatively large amount of Z9-14Aid to a four-component pheromone blend (i.e., Z9-14OH, Z9-14OAc, Z7-14OH, andZ7-14OAc) attractive to Auckland males completely suppressed trap catches of male G.Mutans in Auckland but large numbers of males were caught at both Lincoln and Nelson in traps baited with this five-component blend. In wind-tunnel studies, the addition of even small (1% of amount of Z9-14OH) amounts ofZ9-14Ald to the four-component blend resulted in a significantly greater proportion of Auckland males arresting upwind flight than to the four-com ponent blend. It is suggested that these two populations of G. nations represent distinct sibling species within the described concept.LepidopteraNoctuidaeHadeninae.     

Synthesis of monocarboxylic polyoxyethylenes

Summary The various methods of synthesis which can be used to prepare -carboxy polyoxyethylenes are reviewed. The synthesis and the purification of -methoxy -carboxy polyoxyethylenes ( ) are reported. The process consists of the reaction of halogenoacetic acids with an -methoxy -sodium hydroxylate polyoxyethylene followed by a purification by extraction. ,-dimethoxy and -methoxy -ethyl carboxylate polyoxyethylenes were synthesized.     

Female-produced oviposition deterrents of the cigarette beetle,Lasioderma serricorne (F.) (Coleoptera: Anobiidae)

Oviposition deterrents of the cigarette beetle,Lasioderma serricorne, were isolated from its adult body extract and found to be identical to (2S,3R,1'S)-2,3-dihydro-3,5-dimethyl-2-ethyl-6-(l-methyl-2-oxobutyl)-4H-pyran-4-one (-serricorone) and its lR-epimer (-serricorone) by spectroscopic evidence. Serricorone was previously found as one of the minor sex pheromone components of the same insect, and hence indicating bi-functional nature. The presence of two isomers in the body was proved by careful treatment. Each of them exhibited the same level of oviposition deterring activity, which was less potent than the crude body extract at an increased concentration.     

Shape-Selective Alkylation of Biphenyl over H-[Al]-SSZ-31 with Propylene

Isopropylation of biphenyl (BP) over [Al]-SSZ-31, a large-pore, one-dimensional zeolite has been studied. Effects of temperature, pressure and SiO₂/Al₂O₃ ratio were examined. SSZ-31 was found to be an active catalyst in the isopropylation of biphenyl with propylene. The selectivity for 4-isopropylbiphenyl (4-IPBP) and 4,4-diisopropylbiphenyl (4,4-DIPB) was high among isopropylbiphenyl (IPBP) and diisopropylbiphenyl (DIPB) isomers, respectively, indicating SSZ-31 shows shape-selective catalysis. The selectivity for 4,4-DIPB decreased with temperature increase; correspondingly the selectivity for thermodynamically more stable isomers (3,3- and 3,4 DIPB) increased with temperature. The yield of IPBP isomers decreased while that of DIPB isomers increased with temperature increase. Pressure showed less effect on conversion; however, increase in pressure suppresses the isomerization of 4,4-DIPB to 3,3- and 3,4-DIPB. Conversion decreased with increase in SiO₂/Al₂O₃ ratio. At low SiO₂/Al₂O₃ ratio of 136, relatively high triisopropylbiphenyl (TriIPB) isomers were formed in bulk products and their amount decreased with increase in SiO₂/Al₂O₃ ratio.     

Variable‐temperature IR spectroscopic studies of CO adsorbed on Na‐ZSM‐5 and Na‐Y zeolites

CO interacts with extraframework alkali metal cations (M⁺=) of zeolites to form both M⁺CO and M⁺OC species. By using variabletemperature FTIR spectroscopy, these Cbonded and Obonded species were found to be in a temperaturedependent equilibrium. For the same cation, the difference in interaction energy depends upon the zeolite framework. Thus, for the equilibrium process ZNa⁺=CO ZNa⁺OC, where Z represents the zeolite framework, H ⁰ was found to take the values 3.8 and 2.4 kJ mol^– for CO/NaZSM5 and CO/NaY, respectively. The Cbonded species show always the highest cation–CO interaction energy.     

Methane activation over La2xY2-2xO3 (0 ⩽x ⩽ 1) catalysts

The influence of the structure on the catalytic methane activation coupling activity has been shown for La_2x Y_2–2x O₃ (0 x 1) compounds. A perovskite structure leads to total oxidation (CO, CO₂) whereas a bixbyite structure results in C₂ hydrocarbon formation. This change in selectivity is interpreted in terms of the difference in oxygen environment of lanthanum in the two stuctures.     

Properties ofSrMO 3-δ(M=Fe,Co) as oxygen electrodes in alkaline solution

Strontium ferrates and cobaltates with compositions SrFeO_3- (0.060.40) and SrCoO_3- (0.040.30) were synthesized. The dependence of the oxygen electrode properties on the value was examined in 1 mol dm^–3 KOH solution. In the SrFeO_3- series, the samples with 0.24<<0.29, showed the highest activity in both oxygen evolution and reduction reactions. In contrast, no strong dependence on the value was observed in SrCoO_3-, which also showed a high catalytic activity for oxygen evolution.     

Development and evaluation of an improved soil test for phosphorus: 1. The influence of phosphorus fertilizer solubility and soil properties on the extractability of soil P

The objective of this work was to develop and evaluate a soil test suitable for estimating the phosphorus status of soils whether they were fertilized with soluble or sparingly soluble P fertilizers or both. Four New Zealand soils of contrasting P sorption capacity and exchangeable Ca content were incubated alone or with monocalcium phosphate (MCP), reactive North Carolina (NC) phosphate rock or unreactive Florida (FRD) rock, at 240 mg P kg^–1 soil, to allow the P sources of different solubilities to react with each soil and provide soil samples containing different amounts of extractable P, Ca and residual phosphate rock. The phosphorus in the incubated soils was fractionated into alkali soluble and acid soluble P fractions using a sequential extraction procedure to assess the extent of phosphate rock dissolution. Eight soil P tests [three moderately alkaline — Olsen (0.5M NaHCO₃) modified Olsen (pretreatment with 1M NaCl) and Colwell; three acid tests — Bray 1, modified Bray 1 and Truog; and two resin tests — bicarbonate anion exchange resin (AER) and combined AER plus sodium cation exchange resin (CER)] were assessed in their ability to extract P from the incubated soils.The 0.5M NaHCO₃ based alkaline tests could not differentiate between the Control and FRD treatments in any soil nor between the Control, NC and FRD treatments in the high P sorption soils. The acid extractants appeared to be affected by the P sorption capacity of the soil probably because of reabsorption of dissolved P in the acid medium. The AER test gave results similar to Olsen. Only the combined AER + CER test extracted P in amounts related to the solubility of the P sources incubated with each soil. Furthermore, when soil samples were spiked with FRD and NC and extracted immediately, the P extracted by the AER + CER test, over and above the control soils, increased with the amount and chemical reactivity of the rocks. There was no extraction of rock P by any of the alkaline extractions.Increases in the amounts of P extracted (P) by each soil test from the fertilized soils, over and above the control soils were compared with the amounts ofP dissolved from the fertilizers during incubation (measured by P fractionation). Soil P sorption capacity had least influence on the amounts of P extracted by the AER + CER and Colwell tests. However, the Colwell test was unable to differentiate between all P sources in all four soils and suffered from the disadvantage of producing coloured extracts. The AER + CER test appeared to have the potential to assess the available P status of soils better than the other tests used because of its ability to extract a representative portion of residual PR (in accordance with the amount and reactivity) and dissolved P, and thus to differentiate between fertilizer treatments in all four soils.