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Link P, Glatzel P, Kvashnina K, Smith RI, Ruschewitz U. Yb Valence States in YbC2: A HERFD-XANES Spectroscopic Investigation. Inorg Chem 2011; 50:5587-95. [PMID: 21612187 DOI: 10.1021/ic200247z] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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52
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Powell AS, Stoeva Z, Smith RI, Gregory DH, Titman JJ. Structure, stoichiometry and transport properties of lithium copper nitride battery materials: combined NMR and powder neutron diffraction studies. Phys Chem Chem Phys 2011; 13:10641-7. [DOI: 10.1039/c1cp20368a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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53
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Bull DJ, Sorbie N, Baldissin G, Moser D, Telling MTF, Smith RI, Gregory DH, Ross DK. In situ powder neutron diffraction study of non-stoichiometric phase formation during the hydrogenation of Li3N. Faraday Discuss 2011; 151:263-70; discussion 285-95. [PMID: 22455074 DOI: 10.1039/c0fd00020e] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The hydrogenation of Li3N at low chemical potential has been studied in situ by time-of-flight powder neutron diffraction and the formation of a non-stoichiometric Li4-2xNH phase and Li4NH observed. The results are interpreted in terms of a model for the reaction pathway involving the production of Li4NH and Li2NH, which subsequently react together to form Li4-2xNH. Possible mechanisms for the production of Li4NH from the hydrogenation of Li3N are discussed.
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54
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Mourad MCD, Mokhtar M, Tucker MG, Barney ER, Smith RI, Alyoubi AO, Basahel SN, Shaffer MSP, Skipper NT. Activation and local structural stability during the thermal decomposition of Mg/Al-hydrotalcite by total neutron scattering. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm11530h] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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55
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Ok KM, O'Hare D, Smith RI, Chowdhury M, Fikremariam H. New large volume hydrothermal reaction cell for studying chemical processes under supercritical hydrothermal conditions using time-resolved in situ neutron diffraction. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:125107. [PMID: 21198051 DOI: 10.1063/1.3514990] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The design and testing of a new large volume Inconel pressure cell for the in situ study of supercritical hydrothermal syntheses using time-resolved neutron diffraction is introduced for the first time. The commissioning of this new cell is demonstrated by the measurement of the time-of-flight neutron diffraction pattern for TiO(2) (Anatase) in supercritical D(2)O on the POLARIS diffractometer at the United Kingdom's pulsed spallation neutron source, ISIS, Rutherford Appleton Laboratory. The sample can be studied over a wide range of temperatures (25-450 °C) and pressures (1-355 bar). This novel apparatus will now enable us to study the kinetics and mechanisms of chemical syntheses under extreme environments such as supercritical water, and in particular to study the crystallization of a variety of technologically important inorganic materials.
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Hogan EJ, Minnullina G, Smith RI, Crittenden PD. Effects of nitrogen enrichment on phosphatase activity and nitrogen : phosphorus relationships in Cladonia portentosa. THE NEW PHYTOLOGIST 2010; 186:911-925. [PMID: 20345639 DOI: 10.1111/j.1469-8137.2010.03222.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
*Relationships between nitrogen deposition in the UK and phosphomonoesterase (PME) activity and nitrogen (N) and phosphorus (P) concentrations in Cladonia portentosa were quantified to understand factors limiting lichen growth and to further develop biomarkers for N pollution. *Lichen was collected from sites differing either in rates of wet N (NH(4)(+) + NO(3)(-)) deposition or in annual mean N concentration in rainfall based on both measured and modelled data sets. The PME activity, and total N and P concentrations were measured in specific horizontal strata in lichen mats and PME activity in the thallus was located using an enzyme-labelled fluorescent phosphatase substrate. *With an increase in modelled N deposition from 4.1 to 32.8 kg N ha(-1) yr(-1), PME activity, thallus N and N : P ratio increased by factors of 2.3, 1.4 and 1.8, respectively. Correlations with modelled data were generally stronger than with measured data and those with N deposition were stronger than those with N concentration in rainfall. The PME activity was located solely in the lichen fungus in outer regions of the thallus. *Nitrogen enrichment changes lichen N : P ratios from values typical of N limitation (for example, 10) to those indicative of P limitation (for example, 26) driving upregulation of PME activity.
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57
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Vanek FM, Smith RI. Prospects for rail freight from peripheral regions: The case of North-East Scotland and Grampian Country Foods. INTERNATIONAL JOURNAL OF LOGISTICS-RESEARCH AND APPLICATIONS 2010. [DOI: 10.1080/13675560310001619222] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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58
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Brogan MA, Hughes RW, Smith RI, Gregory DH. Structural and compositional tuning of layered subnitrides; new complex nitride halides. Dalton Trans 2010; 39:7153-8. [DOI: 10.1039/c0dt00214c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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59
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Knee CS, Magrasó A, Norby T, Smith RI. Structural transitions and conductivity of BaPrO3 and BaPr0.9Y0.1O3−δ. ACTA ACUST UNITED AC 2009. [DOI: 10.1039/b820976f] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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60
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Oswald IDH, Chataigner I, Elphick S, Fabbiani FPA, Lennie AR, Maddaluno J, Marshall WG, Prior TJ, Pulham CR, Smith RI. Putting pressure on elusive polymorphs and solvates. CrystEngComm 2009. [DOI: 10.1039/b814471k] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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61
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Leith ID, Mitchell RJ, Truscott AM, Cape JN, van Dijk N, Smith RI, Fowler D, Sutton MA. The influence of nitrogen in stemflow and precipitation on epiphytic bryophytes, Isothecium myosuroides Brid., Dicranum scoparium Hewd. and Thuidium tamariscinum (Hewd.) Schimp of Atlantic oakwoods. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2008; 155:237-246. [PMID: 18343004 DOI: 10.1016/j.envpol.2007.11.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2007] [Revised: 11/23/2007] [Accepted: 11/26/2007] [Indexed: 05/26/2023]
Abstract
The spatial relationship between the concentration and deposition of the major ions in precipitation and stemflow and their influence on the tissue nitrogen concentration of three epiphytic bryophytes on Quercus petraea (Matt) Liebl. and Q. robur L. was investigated at seven UK Atlantic oak woodland sites with a range of total N deposition of 55-250 mmol m(-2). The main driver of change in tissue N concentrations of three epiphytic bryophytes (Isothecium myosuroides Brid. (Eurhynchium myosuroides (Brid.) Schp.), Dicranum scoparium Hewd. and Thuidium tamariscinum (Hewd.) Schimp.) was total N deposition in stemflow, dominated by ammonium deposition. The three epiphytic species also showed strong relationships between tissue N concentration and total N deposition in rainfall but a poor correlation with total N ion concentration in rainfall. This study shows that epiphytic bryophytes utilise stemflow N and thus increase their risk from inputs of total N deposition compared to terricolous species at the same site.
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62
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Paniconi G, Stoeva Z, Smith RI, Dippo PC, Gallagher BL, Gregory DH. Synthesis, stoichiometry and thermal stability of Zn3N2 powders prepared by ammonolysis reactions. J SOLID STATE CHEM 2008. [DOI: 10.1016/j.jssc.2007.11.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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63
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Celestian AJ, Parise JB, Smith RI, Toby BH, Clearfield A. Role of the Hydroxyl−Water Hydrogen-Bond Network in Structural Transitions and Selectivity toward Cesium in Cs0.38(D1.08H0.54)SiTi2O7·(D0.86H0.14)2O Crystalline Silicotitanate. Inorg Chem 2007; 46:1081-9. [PMID: 17291108 DOI: 10.1021/ic0611387] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The crystal structure of the selective Cs+ ion exchanger D1.6H0.4Ti2SiO7.D2.66H0.34O1.5, known as crystalline silicotitanate or CST, has been determined in both native (D-CST) and in the Cs+-exchanged forms ((Cs, D)-CST) from angle-dispersive and time-of-flight neutron diffraction studies. The final fully exchange Cs+ form transformed from D-CST with unit cell parameters a = 11.0704(3) A c = 11.8917(5) A and space group P42/mbc, to one with a = 7.8902(1) A c = 11.9051(4) A and space group P42/mcm. Rietveld structure refinements of both D-CST and (Cs, D)-CST suggest the transition, and ultimately the selectivity, is driven by changes in the positions of water molecules, in response to the initial introduction of Cs+. The changes in water position appear to disrupt the D-O-O-D dihedral associated with the CST framework in space group P42/mbc which ultimately leads to the structural transition. The new geometric arrangement of the water-deuteroxyl network in (Cs, D)-CST suggests that Dwater-Ddeuteroxyl repulsion forced by Cs+ exchange drives the structural transformation.
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64
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Jørgensen JE, Smith RI. On the compression mechanism of FeF3. ACTA CRYSTALLOGRAPHICA SECTION B: STRUCTURAL SCIENCE 2006; 62:987-92. [PMID: 17108651 DOI: 10.1107/s0108768106030023] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2006] [Accepted: 08/01/2006] [Indexed: 11/10/2022]
Abstract
The structure of FeF3, iron trifluoride, has been studied in the pressure range from ambient to 8.28 GPa by time-of-flight neutron powder diffraction. No structural phase transitions were found within the investigated pressure range, and least-squares refinements of the crystal structures were performed in the space group R\overline 3 c for all recorded data sets. It was found that volume reduction is achieved through rotation of the FeF6 octahedra, and the Fe—F—Fe bond angle decreases from 152.5 (2) to 134.8 (3)° within the investigated pressure range. A small octahedral strain was found to develop during compression, which reflects an elongation of the FeF6 octahedra along the c axis. The zero-pressure bulk modulus B_o and its pressure derivative B_o' were determined to be 14 (1) GPa and 12 (1), respectively.
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Fortes AD, Wood IG, Grigoriev D, Alfredsson M, Kipfstuhl S, Knight KS, Smith RI. No evidence for large-scale proton ordering in Antarctic ice from powder neutron diffraction. J Chem Phys 2006; 120:11376-9. [PMID: 15268170 DOI: 10.1063/1.1765099] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We have examined a sample of 3000 year old Antarctic ice, collected at the Kohnen Station, by time-of-flight powder neutron diffraction to test the hypothesis of Fukazawa et al. [e.g., Ann. Glaciol. 31, 247 (2000)] that such ice may be partially proton ordered. Great care was taken to keep our sample below the proposed ordering temperature (237 K) at all times, but we did not observe any evidence of proton ordering.
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66
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Bowman A, Smith RI, Gregory DH. Synthesis and structure of the ternary and quaternary strontium nitride halides, Sr2N(X, X′) (X, X′=Cl, Br, I). J SOLID STATE CHEM 2006. [DOI: 10.1016/j.jssc.2005.10.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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67
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Fowler D, Smith RI, Muller JBA, Hayman G, Vincent KJ. Changes in the atmospheric deposition of acidifying compounds in the UK between 1986 and 2001. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2005; 137:15-25. [PMID: 15944037 DOI: 10.1016/j.envpol.2004.12.028] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2004] [Accepted: 12/17/2004] [Indexed: 05/02/2023]
Abstract
Emissions of a precursor of acidity in precipitation, sulphur dioxide (SO2), declined in the UK and the EU (15) by 71% and 72%, respectively, between 1986 and 2001, while nitrous oxide emissions declined by about 40%. Acidity in UK precipitation and the deposition of sulphate in precipitation halved during this period, but reductions were larger in the English Midlands than at the west coast and in high rainfall areas (>2000 mm). There is evidence that the smaller reductions in sulphur deposition in the west and south are due in part to shipping sources of SO2. Reductions in sulphur dry deposition (74%) are larger than in wet deposition (45%), due to changes in the canopy resistance to dry deposition. For reduced nitrogen, there has been a small (10%) reduction in emissions and deposition, while for oxidized nitrogen, a substantial reduction in emissions (40%) occurred but wet deposition of nitrate changed by less than 10%.
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68
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Harvey EJ, Whittle KR, Lumpkin GR, Smith RI, Redfern SA. Solid solubilities of (La Nd,)2(Zr,Ti)2O7 phases deduced by neutron diffraction. J SOLID STATE CHEM 2005. [DOI: 10.1016/j.jssc.2004.12.030] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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69
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Jørgensen JE, Marshall WG, Smith RI. The compression mechanism of CrF3. ACTA CRYSTALLOGRAPHICA SECTION B: STRUCTURAL SCIENCE 2004; 60:669-73. [PMID: 15534376 DOI: 10.1107/s010876810402316x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2004] [Accepted: 09/17/2004] [Indexed: 11/10/2022]
Abstract
The structure of CrF3 has been studied in the pressure range from ambient to 9.12 GPa by time-of-flight neutron powder diffraction. Rietveld refinements of the crystal structure were performed in the space group R\overline 3 c for all the recorded data sets. It was found that volume reduction is achieved through rotation of the CrF6 octahedra and that the Cr—F—Cr bond angle decreases from 144.80 (7) to 133.9 (4)° within the investigated pressure range. Furthermore, a small octahedral strain was found to develop during compression. The octahedral strain reflects an elongation of the CrF6 octahedra along the c-axis direction. The zero-pressure bulk modulus B
o
and its pressure derivative B_o^{\prime} were determined to be B
o
= 29.2 (4) GPa and B^{\prime}_o = 10.1 (3).
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70
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Sutton MA, Dragosits U, Hellsten S, Place CJ, Dore AJ, Tang YS, van Dijk N, Love L, Fournier N, Vieno M, Weston KJ, Smith RI, Coyle M, Roy D, Hall J, Fowler D. Ammonia emission and deposition in Scotland and its potential environmental impacts. ScientificWorldJournal 2004; 4:795-810. [PMID: 15349519 PMCID: PMC5956370 DOI: 10.1100/tsw.2004.130] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
The main source of atmospheric ammonia (NH3) in Scotland is livestock agriculture, which accounts for 85% of emissions. The local magnitude of emissions therefore depends on livestock density, type, and management, with major differences occurring in various parts of Scotland. Local differences in agricultural activities therefore result in a wide range of NH3 emissions, ranging from less than 0.2 kg N ha−1 year−1 in remote areas of the Scottish Highlands to over 100 kg N ha−1 year−1 in areas with intensive poultry farming. Scotland can be divided loosely into upland and lowland areas, with NH3 emission being less than and more than 5 kg N ha−1 year−1, respectively.Many semi-natural ecosystems in Scotland are vulnerable to nitrogen deposition, including bogs, moorlands, and the woodland ground flora. Because NH3 emissions occur in the rural environment, the local deposition to sensitive ecosystems may be large, making it essential to assess the spatial distribution of NH3 emissions and deposition. A spatial model is applied here to map NH3 emissions and these estimates are applied in atmospheric dispersion and deposition models to estimate atmospheric concentrations of NH3 and NH4+, dry deposition of NH3, and wet deposition of NHx. Although there is a high level of local variability, modelled NH3 concentrations show good agreement with the National Ammonia Monitoring Network, while wet deposition is largest at high altitude sites in the south and west of Scotland. Comparison of the modelled NHx deposition fields with estimated thresholds for environmental effects (“critical loads”) shows that thresholds are exceeded across most of lowland Scotland and the Southern Uplands. Only in the cleanest parts of the north and west is nitrogen deposition not a cause for concern. Given that the most intense effects occur within a few kilometres of sources, it is suggested that local spatial abatement policies would be a useful complement to traditional policies that mitigate environmental effects based on emission reduction technologies.
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71
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Howard CJ, Lumpkin GR, Smith RI, Zhang Z. Crystal structures and phase transition in the system SrTiO3–La2/3TiO3. J SOLID STATE CHEM 2004. [DOI: 10.1016/j.jssc.2004.04.018] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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72
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Berdonosov PS, Charkin DO, Dolgikh VA, Stefanovich SY, Smith RI, Lightfoot P. Bi2−xLnxWO6: a novel layered structure type related to the Aurivillius phases. J SOLID STATE CHEM 2004. [DOI: 10.1016/j.jssc.2004.03.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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73
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Dick JM, Leakey RRB, McBeath C, Harvey F, Smith RI, Woods C. Influence of nutrient application rate on growth and rooting potential of the West African hardwood Triplochiton scleroxylon. TREE PHYSIOLOGY 2004; 24:35-44. [PMID: 14652212 DOI: 10.1093/treephys/24.1.35] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Effects of stock plant nutrition on growth and subsequent rooting of leafy stem cuttings of the commercially important west African tree Triplochiton scleroxylon K. Schum. were investigated to identify the primary morphological variables influencing adventitious root formation. Potted plants were watered as required with one of four balanced nutrient solutions (0, 15, 63 or 125 mg N l(-1)). Increasing the nutrient supply to stock plants increased growth rate and rate of adventitious root production of subsequently harvested cuttings, but an optimum nutrient regime was not identified. Rooting percentage increased from 27% in cuttings harvested from stock plants receiving a low nutrient supply to 64% for cuttings harvested from stock plants receiving eight times the amount of nutrients extractable from plants under typical field conditions in West Africa. The ability of a cutting to retain its leaf during propagation and the length of the cutting were the primary measured characteristics associated with rooting and accounted for 43% of the variance fitted in the model. The length of the new shoot, total leaf area and within-shoot position (node position) were also significantly associated with rooting. After these characteristics were fitted to the model, the genetic origin (clone) was not statistically significant. We conclude that genetic variation in rooting potential is mediated through variations in morphological and physiological traits, rather than through genetic variation in cell differentiation or related aspects of root initiation.
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Gordon AG, Smith RI, Wilson C, Stoeva Z, Gregory DH. Crystal growth, defect structure and magnetism of new Li3N-derived lithium nitridocobaltates. Chem Commun (Camb) 2004:2812-3. [PMID: 15599419 DOI: 10.1039/b413022g] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
New nitridocobaltates Li(3-x-y)Co(x)N are revealed to contain significant Li(+) vacancies (y approximately 0.45) disordered within lithium-nitrogen planes and to exist as partially delocalised spin systems as a result of increased covalency through infinite -N-(Li,Co)-N- chains.
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75
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Walton RI, Norquist A, Smith RI, O'Hare D. Recent results from the in situ study of hydrothermal crystallisations using time-resolved X-ray and neutron diffraction methods. Faraday Discuss 2003; 122:331-41; discussion 381-93. [PMID: 12555866 DOI: 10.1039/b200990k] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present new time-resolved powder diffraction data measured in situ during the hydrothermal crystallisation of two families of crystalline inorganic materials. In the first study, we have used time-resolved energy-dispersive X-ray diffraction (EDXRD) to follow the formation of zeolitic zinc phosphates from amine phosphates and zinc oxide in acidic solutions at 60-150 degrees C. The advantage of this method is the ability to penetrate a laboratory-sized reaction vessel and to measure data in short (< 1 min) time intervals. Integration of the Bragg peak intensities during the crystallisation of the product allows accurate crystallisation curves to be produced. In addition, in a number of cases, we observe the formation of transient crystalline intermediate phases which can be identified by use of a new three-element detector that allows a large amount of diffraction data to be measured during the experiment. We are thus able to show that three-dimensional zinc phosphate architectures often form via low-dimensional chain and layered phases, which is consistent with a recent aufbau model proposed for their formation. In the second study, we focus on the hydrothermal formation of ferroelectric barium titanate from TiO2 and barium salts in alkaline solution using time-resolved neutron diffraction. Although the time resolution of the neutron diffraction experiment is lower than the EDXRD experiment (data are measured in intervals of 5 min), we are able to penetrate reaction mixtures that are highly absorbing towards X-rays, and thus can measure data in a large volume reaction cell. Neutron diffraction data were collected on one of the highest-flux/highest detector-coverage diffractometers currently available; the GEM diffractometer at ISIS, UK. These experiments reveal that BaTiO3 crystallises after a large amount of TiO2 has been consumed; this implies that a dissolution crystallisation mechanism predominates. Additional mechanistic information is inferred by the observation of transient crystalline phases under certain reaction conditions.
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