ORCID Profile
0000-0002-4008-9842
Current Organisation
University of Wollongong
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In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Materials Engineering Not Elsewhere Classified | Materials Engineering | Electrical and Electronic Engineering | Electrochemistry | Manufacturing Engineering Not Elsewhere Classified | Nanotechnology | Condensed Matter Physics—Electronic And Magnetic Properties; | Photonics and Electro-Optical Engineering (excl. Communications) | Power and Energy Systems Engineering (excl. Renewable Power) | Nanotechnology | Ceramics | Precision Engineering | Composite Materials | Alloy Materials | Manufacturing Engineering | Other Electronic Engineering | Electrical Engineering | Machining | Biomaterials | Nanophotonics | Climatology (Incl. Palaeoclimatology) | Nanomanufacturing | Inorganic Chemistry Not Elsewhere Classified | Interdisciplinary Engineering Not Elsewhere Classified | Engineering Instrumentation | Electronic and Magnetic Properties of Condensed Matter; Superconductivity | Nanofabrication, Growth and Self Assembly
Energy storage | Energy transformation | Electricity transmission | Metals (composites, coatings, bonding, etc.) | Scientific instrumentation | Scientific Instruments | Iron and steel (e.g. ingots, bars, rods, shapes and sections) | Solar-thermal electric | Industry | Physical sciences | Ceramics, glass and industrial mineral products not elsewhere classified | Renewable energy not elsewhere classified (e.g. geothermal) | Inorganic industrial chemicals | Ceramics | Other | Renewable energy | Industrial instrumentation | Medical instrumentation | Energy distribution not elsewhere classified | Industrial Instruments | Expanding Knowledge in the Physical Sciences | Expanding Knowledge in Engineering |
Publisher: AIP Publishing
Date: 30-08-2005
DOI: 10.1063/1.2039993
Abstract: Interaction between the superconductor and ferromagnet in MgB2∕Fe wires results in either a plateau or a peak effect in the field dependence of transport critical current, Ic(H). This is in addition to magnetic shielding of external field. Current theoretical models cannot account for the observed peak effect in Ic(H). This letter shows that the theoretical explanation of the peak effect should be sought in terms of interaction between superconductor and magnetic domain structure, obtained after the remagnetization of the iron sheath by the self-field of the current. There is a minimum value of critical current, below which the remagnetization of the iron sheath and peak effect in Ic(H) are not observed.
Publisher: IEEE
Date: 09-2013
Publisher: Elsevier BV
Date: 02-1992
Publisher: World Scientific Pub Co Pte Lt
Date: 30-10-1996
DOI: 10.1142/S0217984996001413
Abstract: An additional broad peak in AC losses of Bi 2 Sr 2 Ca 1 Cu 2 O x tapes is observed. Using a new method based on the model of separated finite-size stacks of superconducting layers it is found that this peak reflects the presence of Bi 2 Sr 2 CuO x intergrowth in the s le. Kosterlitz-Thouless transition temperatures of pure Bi 2 Sr 2 Ca 1 Cu 2 O x and intergrowths of different thickness are defined. Our results are confirmed by the direct TEM measurements.
Publisher: IEEE
Date: 08-11-2020
Publisher: Wiley
Date: 16-12-1992
Publisher: AIP Publishing
Date: 15-02-2006
DOI: 10.1063/1.2171772
Abstract: An alternative method for determining the lock-in angle φL for pinning of the vortices on extended defects has been developed. This method does not require any preassumed criterion for defining φL. Highly twinned Sm1+xBa2−xCu3O6+y single crystal was used for demonstrating the method. Appropriate scaling of the hysteresis loops measured for different angles between the field and twin planes in highly twinned SmBaCuO single crystal led to a clear discrimination between two vortex dynamics regimes. From this scaling, the lock-in angle was determined to be 6°±0.1° for the single crystal investigated. This method significantly reduces the uncertainty in determining the lock-in angle when compared to all the other currently employed methods.
Publisher: Wiley
Date: 16-07-1993
Publisher: Elsevier BV
Date: 04-2020
DOI: 10.1016/J.SCITOTENV.2019.136431
Abstract: Biochar-based compound fertilizers (BCF) and amendments have proven to enhance crop yields and modify soil properties (pH, nutrients, organic matter, structure etc.) and are now in commercial production in China. While there is a good understanding of the changes in soil properties following biochar addition, the interactions within the rhizosphere remain largely unstudied, with benefits to yield observed beyond the changes in soil properties alone. We investigated the rhizosphere interactions following the addition of an activated wheat straw BCF at an application rates of 0.25% (g·g
Publisher: AIP Publishing
Date: 08-07-2003
DOI: 10.1063/1.1591070
Abstract: In this work, we report the discovery of a vortex pinning source: semicrystalline defect wells in self-aligned nanostructured MgB2. It is demonstrated that these aperiodic regions trap numerous crystal defects migrating along nanodomain boundaries during self-alignment and act as intense vortex pinning centers that significantly enhance the high-field performance of MgB2. This suggests that the density of trapped defects in the wells is much greater than that found in other vortex pinning sources.
Publisher: IOP Publishing
Date: 10-1998
Publisher: AIP Publishing
Date: 06-2001
DOI: 10.1063/1.1356055
Abstract: Studies of superconductivity and flux pinning were carried out on (Bi1.64Pb0.36)Sr2Ca1−xYxCu2O8+y (x=0, 0.05, 0.11, 0.33) single crystals grown by the self-flux method. X-ray diffraction, transport, and magnetic measurements were performed for purposes of characterization. X-ray analysis revealed that the c lattice parameter systemically decreases as the Y doping level increases. The superconducting transition temperature Tc decreases from 80 to 30 K as x increases. A strong annealing effect on Tc and superconducting volume has been observed. Resistance measurements show that x=0.33 s les are semiconductive over a wide temperature range between 4.2 and 300 K for the as-grown state, but become metallic with Tc of 65–70 K after air or oxygen annealing. Flux pinning was studied by measuring the hysteresis loop at different temperatures and different fields. A peak effect was observed in all the codoped s les. Results show that at low temperatures, the peak field is smaller than in solely Pb doped crystals and decreases as x increases (x& .1). However, the peak field at high temperature for the x=0.05 s le is higher than in heavily Pb doped Bi2212 crystals, indicative of a strong pinning due to the codoping.
Publisher: IOP Publishing
Date: 09-1989
Publisher: Elsevier BV
Date: 04-1992
Publisher: IOP Publishing
Date: 10-1998
Publisher: Springer Science and Business Media LLC
Date: 2003
Publisher: Wiley
Date: 16-05-1992
Publisher: Elsevier BV
Date: 2012
Publisher: Royal Society of Chemistry (RSC)
Date: 2022
DOI: 10.1039/D1CP05718A
Abstract: Periodic density-functional theory is used to investigate the effect of cell contraction on the accuracy of simulated terahertz absorption spectra.
Publisher: IOP Publishing
Date: 26-09-2002
Publisher: Springer Science and Business Media LLC
Date: 20-05-2021
Publisher: IOP Publishing
Date: 20-05-2013
Publisher: IOP Publishing
Date: 10-08-2004
Publisher: American Chemical Society (ACS)
Date: 26-11-2019
Publisher: IOP Publishing
Date: 26-01-2004
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D0CP06354A
Abstract: Magnetization reversal occurs over 1 min for NdFeO 3 crystals, while it occurs over a fraction of a second for ErFeO 3 crystals.
Publisher: Wiley
Date: 05-08-2010
Publisher: Elsevier BV
Date: 07-2003
Publisher: American Physical Society (APS)
Date: 18-11-2019
Publisher: Elsevier BV
Date: 05-2014
Publisher: Elsevier BV
Date: 03-1998
Publisher: IOP Publishing
Date: 13-07-2007
Publisher: Elsevier BV
Date: 04-1992
Publisher: Trans Tech Publications, Ltd.
Date: 04-2003
Publisher: IOP Publishing
Date: 10-1998
Publisher: AIP Publishing
Date: 27-10-2005
DOI: 10.1063/1.2126148
Abstract: The influence of heating rates and annealing temperatures on the transition temperatures (Tc) and critical current densities (Jc) of pure MgB2, carbon nanotube- and nano-SiC-doped in situ monofilamentary MgB2∕Fe wires was investigated. It was found that higher Jc was obtained for pure MgB2 s les when heat treated with slower heating rates. SiC-doped s les also have higher Jc with slower heating rates, but the Jc is less sensitive to annealing temperatures. However, the Jc of the carbon nanotube-doped wire was found to be insensitive to heating rates. The variation in Tc and Jc with heating rate, and the different behaviors of differently doped MgB2∕Fe wires, make it essential to carefully select the optimum heating rates for heat treatment.
Publisher: IOP Publishing
Date: 18-10-2002
Publisher: Elsevier BV
Date: 05-2021
Publisher: EDP Sciences
Date: 23-12-2010
Publisher: American Chemical Society (ACS)
Date: 06-09-2008
DOI: 10.1021/JP803869E
Publisher: Elsevier BV
Date: 04-1997
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 06-2003
Publisher: IOP Publishing
Date: 08-1998
Publisher: Optica Publishing Group
Date: 13-07-2009
DOI: 10.1364/OL.34.002195
Publisher: Elsevier BV
Date: 10-1991
Publisher: IOP Publishing
Date: 10-1998
Publisher: Trans Tech Publications, Ltd.
Date: 04-2003
Publisher: Elsevier BV
Date: 09-2001
Publisher: IEEE
Date: 09-2014
Publisher: Elsevier BV
Date: 05-1998
Publisher: Elsevier BV
Date: 2004
Publisher: IEEE
Date: 09-2014
Publisher: Informa UK Limited
Date: 2003
Publisher: Wiley
Date: 06-12-2011
Abstract: Polyhedral magnetite nanocrystals with multiple facets were synthesised by a low temperature hydrothermal method. Atomistic simulation and calculations on surface attachment energy successfully predicted the polyhedral structure of magnetite nanocrystals with multiple facets. X-ray diffraction, field emission scanning electron microscopy, and high resolution transmission microscopy confirmed the crystal structure of magnetite, which is consistent with the theoretical modelling. The magnetic property measurements show the superspin glass state of the polyhedral nanocrystals, which could originate from the nanometer size of in idual single crystals. When applied as an anode material in lithium ion cells, magnetite nanocrystals demonstrated an outstanding electrochemical performance with a high lithium storage capacity, a satisfactory cyclability, and an excellent high rate capacity.
Publisher: Springer Science and Business Media LLC
Date: 19-07-2016
Publisher: AIP Publishing
Date: 20-03-2020
DOI: 10.1063/1.5115518
Abstract: Rare earth orthoferrites demonstrate great application potentials in spintronics and optical devices due to their multiferroic and magnetooptical properties. In RFeO3, magnetic R3+ undergo a spontaneous spin reorientation in a temperature range determined by R (rare earth), where the magnetic structure changes from Γ2 to Γ4. The b-axis component of their magnetic moment, Mb, is reported in numerous neutron diffraction studies to remain zero at all temperatures. More sensitive magnetometer measurements reveal a small non-zero Mb, which is minute above ∼200 K. Mb increases with cooling and reaches values of ∼10–3 μB/f.u. at temperatures within or below the spin reorientation temperatures. Our results can be explained by assuming the Fe3+ spins as the origin of non-zero Mb, while R3+ spins suppress Mb. The representation analysis of point groups shows that non-zero Mb is associated with a small admixture of the Γ3 phase to Γ2 or Γ4. Such a mixing of the three magnetic phases requires at least a fourth order of the spin Hamiltonian for RFeO3 to describe the non-zero Mb.
Publisher: Elsevier BV
Date: 09-2001
Publisher: Elsevier BV
Date: 11-2001
Publisher: IOP Publishing
Date: 10-1996
Publisher: IOP Publishing
Date: 10-1996
Publisher: AIP Publishing
Date: 22-10-2002
DOI: 10.1063/1.1517398
Abstract: Doping of MgB2 by nano-SiC and its potential for the improvement of flux pinning were studied for MgB2−x(SiC)x/2 with x=0, 0.2, and 0.3 and for 10 wt % nano-SiC-doped MgB2 s les. Cosubstitution of B by Si and C counterbalanced the effects of single-element doping, decreasing Tc by only 1.5 K, introducing intragrain pinning centers effective at high fields and temperatures, and significantly enhancing Jc and Hirr. Compared to the undoped s le, Jc for the 10 wt % doped s le increased by a factor of 32 at 5 K and 8 T, 42 at 20 K and 5 T, and 14 at 30 K and 2 T. At 20 K and 2 T, the Jc for the doped s le was 2.4×105 A/cm2, which is comparable to Jc values for the best Ag/Bi-2223 tapes. At 20 K and 4 T, Jc was twice as high as for the best MgB2 thin films and an order of magnitude higher than for the best Fe/MgB2 tapes. The magnetic Jc is consistent with the transport Jc which remains at 20 000 A/cm2 even at 10 T and 5 K for the doped s le, an order of magnitude higher than the undoped one. Because of such high performance, it is anticipated that the future MgB2 conductors will be made using a formula of MgBxSiyCz instead of pure MgB2.
Publisher: Elsevier BV
Date: 05-1989
Publisher: Elsevier BV
Date: 09-2001
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 06-1999
DOI: 10.1109/77.784967
Publisher: Elsevier BV
Date: 2004
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 06-2003
Publisher: Elsevier BV
Date: 2021
Publisher: IOP Publishing
Date: 05-04-2005
Publisher: IOP Publishing
Date: 02-05-2001
Publisher: Elsevier BV
Date: 11-2014
Publisher: AIP Publishing
Date: 1997
DOI: 10.1063/1.364093
Abstract: Bi2Sr2CaCu2Oy (Bi2212) crystals with CuO inclusions were grown on the surface of KCl flux. The density of CuO incorporations of 109/cm2 was similar to that for Y2BaCuOy in melt-textured YBa2Cu3Oy. The CuO inclusions are needlelike particles with diameter of less than 1 μm. Magnetization measurements show enhanced flux pinning at high magnetic field, compared to crystals without CuO.
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 03-2004
Publisher: IOP Publishing
Date: 06-2010
Publisher: AIP Publishing
Date: 13-04-2004
DOI: 10.1063/1.1713031
Abstract: A strong effect of s le size on magnetic Jc(H) was observed for bulk MgB2 when Jc is obtained directly from the critical state model. Thus obtained zero-field Jc (Jc0) decreases strongly with the s le size, attaining a constant value for the s les larger than a few millimeters. On the other hand, the irreversibility field (Hirr) defined at Jc=100 A/cm2 increases with the s le size. The decrease of Jc0 is described in terms of voids in the bulk MgB2 s les and superconducting screening around the cells of superconducting material between these voids (35 μm), because of concentration of the current in the narrow bridges connecting the cells. For s les larger than a few millimeters, the value of magnetic Jc is in agreement with the transport Jc and it is restricted by the voids. The critical state model is not suitable for obtaining Jc for small bulk MgB2. The increase of Hirr with the s le size is an artifact of defining Hirr by the value of Jc at which an additional superconducting screening on 1 μm scale dominates Δm.
Publisher: Elsevier BV
Date: 09-2007
Publisher: Elsevier BV
Date: 11-2002
Publisher: American Chemical Society (ACS)
Date: 04-05-2015
DOI: 10.1021/JP512165Q
Publisher: Elsevier BV
Date: 05-2016
Publisher: American Chemical Society (ACS)
Date: 05-03-2013
DOI: 10.1021/IC301579G
Abstract: Manganese-based layered coordination polymer ([Mn(tfbdc)(4,4'-bpy)(H2O)2], Mn-LCP) with microporous structure was synthesized by reaction of 2,3,5,6-tetrafluoroterephthalatic acid(H2tfbdc) and 4,4'-bipyridine(4,4'-bpy) with manganese(II) acetate tetrahydrate in water solution. Mn-LCP was characterized by elemental analysis, IR spectra, thermogravimetric analysis, X-ray single-crystal structure analysis, and powder X-ray diffraction. Magnetic susceptibility data from 300 to 1.8K show that there is a weak antiferromagnetic exchange between Mn(II) ions in Mn-LCP. As anode material, the Mn-LCP electrode exhibits an irreversible high capacity in the first discharge process and a reversible lithium storage capacity of up to about 390 mA h/g from the fourth cycle. It might provide a new method for finding new electrode materials in lithium-ion batteries.
Publisher: IOP Publishing
Date: 06-2010
Publisher: IEEE
Date: 29-08-2021
Publisher: Elsevier BV
Date: 07-2000
Publisher: IOP Publishing
Date: 31-01-2002
Publisher: AIP Publishing
Date: 15-04-2008
DOI: 10.1063/1.2909203
Abstract: MgB 2 / Fe wires with 10 at. % excess Mg produced by in situ powder-in-tube processing were compared to normal stoichiometric MgB2/Fe wires prepared by the same method. It was found that the critical current density (Jc) and the irreversibility field (Hirr) were significantly enhanced for MgB2/Fe wires with excess Mg. The transport Jc for 10 at. % Mg excess s les sintered at 800 °C, measured at a field of up to 14 T, increased by a factor of 2 compared to that for the normal MgB2 wires. The best Jc results for the 10 at. % Mg excess s le were obtained by heating the s le at 600 °C for 1 h the Jc at a field of 8 T and at temperature of 10 K reached 3×104 A/cm2. The detailed analysis of the effect of excess Mg on the microstructures, the Jc, and the Hirr, of MgB2/Fe wires are presented in this paper.
Publisher: IOP Publishing
Date: 31-01-2002
Publisher: Elsevier BV
Date: 07-2004
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 06-2009
Publisher: Royal Society of Chemistry (RSC)
Date: 2015
DOI: 10.1039/C5NR06676J
Abstract: In this study we report in-plane nanotracks produced by molecular-beam-epitaxy (MBE) exhibiting lateral self-assembly and unusual periodic and out-of-phase height variations across their growth axes.
Publisher: Springer Science and Business Media LLC
Date: 14-04-2014
DOI: 10.1038/ONC.2014.99
Abstract: Interleukin (IL)-6 family cytokines signal exclusively via the gp130 coreceptor, and are implicated in smoking-associated lung cancer, the most lethal cancer worldwide. However, the role of gp130 signalling pathways in transducing the carcinogenic effects of tobacco-related compounds is ill-defined. Here, we report that lung tumourigenesis induced by the potent tobacco carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (Nicotine-derived Nitrosamine Ketone NNK) is suppressed in gp130(F/F) knock-in mice characterized by the contrasting gp130-dependant hypoactivation of extracellular signal-regulated kinase mitogen-activated protein kinase (ERK MAPK) and phosphatidylinositol 3-kinase/Akt, and hyperactivation of signal transducer and activator of transcription (STAT)3 signalling cascades. Specifically, in response to NNK, the absolute number and size of lung lesions in gp130(F/F) mice were significantly reduced compared with gp130(+/+) littermate controls, and associated with lower cellular proliferation without any alteration to the level of apoptosis in gp130(F/F) lung tumours. At the molecular level, reduced activation of ERK MAPK, but not Akt, was observed in lung tumours of gp130(F/F) mice, and corresponded with impaired expression of several tumour suppressor genes (for ex le, Trp53, Tsc2). Notably, STAT3 was not activated in the lungs of gp130(+/+) mice by NNK, and genetic normalization of STAT3 activation in gp130(F/F):Stat3(-/+) mice had no effect on NNK-induced tumourigenesis. The expression of tumour suppressor genes was reduced in tumours from current versus never-smoking lung cancer patients, and in vitro pharmacological inhibition of ERK MAPK signalling in human lung cancer cells abrogated NNK-induced downmodulation of tumour suppressor gene expression. Among IL-6 cytokine family members, IL-6 gene expression was specifically upregulated by NNK in vitro and in vivo, and inversely correlated with tumour suppressor gene expression. Collectively, our data reveal that a key molecular mechanism by which NNK promotes tumour cell proliferation during tobacco carcinogen-induced lung carcinogenesis is via upregulation of IL-6 and the preferential usage of gp130-dependant ERK MAPK signalling to downmodulate tumour suppressor gene expression.
Publisher: AIP Publishing
Date: 17-11-2020
DOI: 10.1063/5.0029036
Abstract: Raman spectra of aerographite, graphite oxide, graphite flakes, and kish graphite were investigated with different laser excitation energies (wavelengths, λL), namely, 2.81 eV (442 nm), 2.41 eV (514 nm), 2.33 eV (532 nm), and 1.96 eV (633 nm). X-ray diffraction analysis showed that aerographite and graphite oxide are structurally disordered. The Raman spectra of both exhibit typical graphitic features, namely, G, D, D′, and 2D bands. The D and 2D bands exhibit a “blue-shift” with laser excitation energies, EL, while the G bands remain invariant. The intensity ratio between the D and G bands (ID/IG) ranges from 0.70 to 1.25 for aerographite and graphite oxide and from 0.04 to 0.24 for graphite flakes and kish graphite. The dependence of ID/IG on λL4 is linear for graphite flakes and kish graphite, while it saturates at the longest λL for aerographite and graphite oxide. A physical explanation of this unexpected saturation is proposed within the double resonant Raman scattering model, taking into account the disorder-induced changes of the phonon density of states.
Publisher: IOP Publishing
Date: 10-08-2004
Publisher: AIP Publishing
Date: 27-09-2010
DOI: 10.1063/1.3493653
Abstract: It has previously been reported that x-rays are emitted when adhesive tape is peeled in a vacuum but no account of the dependence of the x-ray emission on the pressure of the environment has been given to date. In this paper we present detailed experimental data on the number and angular distribution of x-ray photons as a function of pressure. We find that x-rays are emitted for pressures between p0=10−3 and p1=10−2 mBar, with ∼106 counts/(cm2 s) recorded by a 256×256 pixel2 silicon array sensor placed 35 mm from the tape. The main role of the tape is found to be the build-up of an acceleration potential sufficient to produce x-rays by bremsstrahlung of free electrons in a low-pressure gas. The source of the free electrons is the gas. Our model shows that the production rate of uncompensated tape charge and absorption of positive ions from the gas define p1. The angular distribution of the radiation shows a pressure-independent 20° wide peak in the direction perpendicular to electron motion. Ordinary bremsstrahlung cannot describe this peak.
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 06-1999
DOI: 10.1109/77.785045
Publisher: American Chemical Society (ACS)
Date: 30-07-2018
Abstract: The terahertz absorption spectra of aspirin and benzoic acid have been measured in the range 200-500 cm
Publisher: IOP Publishing
Date: 06-02-2002
Publisher: Royal Society of Chemistry (RSC)
Date: 2023
DOI: 10.1039/D2CP05753K
Abstract: The effect of temperature change on the magnetic moment for rare earth ions in RFeO 3 .
Publisher: Elsevier BV
Date: 12-2017
DOI: 10.1016/J.SCITOTENV.2017.06.186
Abstract: Recent studies have shown that the pyrolysis of biomass combined with clay can result in both lower cost and increase in plant yields. One of the major sources of nutrients for pasture growth, as well as fuel and building materials in Tibet is yak dung. This paper reports on the initial field testing in a pasture setting in Tibet using yak dung, biochar, and attapulgite clay/yak dung biochars produced at ratios of 10/90 and 50/50 clay to dung. We found that the treatment with attapulgite clay/yak dung (50/50) biochar resulted in the highest pasture yields and grass nutrition quality. We also measured the properties and yields of mixtures of clay/yak dung biochar used in the field trials produced at 400°C and 500°C to help determine a possible optimum final pyrolysis temperature and dung/clay ratio. It was observed that increasing clay content increased carbon stability, overall biochar yield, pore size, carboxyl and ketone/aldehyde functional groups, hematite and ferrous/ferric sulphate/thiosulphate concentration, surface area and magnetic moment. Decreasing clay content resulted in higher pH, CEC, N content and an enhanced ability to accept and donate electrons. The resulting properties were a complex function of both processing temperature and the percentage of clay for the biochars processed at both 400°C and 500°C. It is possible that the increase in yield and nutrient uptake in the field trial is related to the higher concentration of C/O functional groups, higher surface area and pore volume and higher content of Fe/O/S nanoparticles of multiple oxidation state in the 50/50 clay/dung. These properties have been found to significantly increase the abundance of beneficial microorganisms and hence improve the nutrient cycling and availability in soil. Further field trials are required to determine the optimum pyrolysis production conditions and application rate on the abundance of beneficial microorganisms, yields and nutrient quality.
Publisher: Elsevier BV
Date: 05-1993
Publisher: Elsevier BV
Date: 02-2000
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 06-1999
DOI: 10.1109/77.785049
Publisher: IEEE
Date: 08-2017
Publisher: IOP Publishing
Date: 05-04-2005
Publisher: Elsevier BV
Date: 1997
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 06-2003
Publisher: IOP Publishing
Date: 05-04-2005
Publisher: IOP Publishing
Date: 26-04-2006
Publisher: IOP Publishing
Date: 12-1995
Publisher: IOP Publishing
Date: 02-07-2004
Publisher: American Chemical Society (ACS)
Date: 20-02-2009
DOI: 10.1021/JP8106149
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 06-2007
Publisher: AIP Publishing
Date: 13-09-2023
DOI: 10.1063/5.0165307
Publisher: Springer Science and Business Media LLC
Date: 05-07-2016
DOI: 10.1038/SREP28860
Abstract: Herein we investigate a (001)-oriented GaAs 1− x Bi x /GaAs structure possessing Bi surface droplets capable of catalysing the formation of nanostructures during Bi-rich growth, through the vapour-liquid-solid mechanism. Specifically, self-aligned “nanotracks” are found to exist trailing the Bi droplets on the s le surface. Through cross-sectional high-resolution transmission electron microscopy the nanotracks are revealed to in fact be elevated above surface by the formation of a subsurface planar nanowire, a structure initiated mid-way through the molecular-beam-epitaxy growth and embedded into the epilayer, via epitaxial overgrowth. Electron microscopy studies also yield the morphological, structural and chemical properties of the nanostructures. Through a combination of Bi determination methods the compositional profile of the film is shown to be graded and inhomogeneous. Furthermore, the coherent and pure zincblende phase property of the film is detailed. Optical characterisation of features on the s le surface is carried out using polarised micro-Raman and micro-photoluminescence spectroscopies. The important light producing properties of the surface nanostructures are investigated through pump intensity-dependent micro-PL measurements, whereby relatively large local inhomogeneities are revealed to exist on the epitaxial surface for important optical parameters. We conclude that such surface effects must be considered when designing and fabricating optical devices based on GaAsBi alloys.
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 06-1999
DOI: 10.1109/77.785053
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 06-2003
Publisher: Elsevier BV
Date: 06-1991
Publisher: Elsevier BV
Date: 11-2021
Publisher: IEEE
Date: 09-2013
Publisher: AIP Publishing
Date: 12-03-2012
DOI: 10.1063/1.3679148
Abstract: VNx nanoparticles and nanowires have been prepared by nitrifying V2O5 nanoparticles (NP) and nanowires (NW). The V2O5 NP and NW were synthesized by a facile hydrothermal method. Magnetic susceptibility (χ) and magnetization measurements showed long range superconducting ordering (LRSO) at the temperature of 5.8 K for NW, but there was no observation of LRSO (at least down to 2 K) for the NP s le, which is a much lower temperature than for the corresponding bulk, while both NP and NW showed the absence of long range magnetic ordering, at least down to 2 K. However, the χ data showed that both s les possess a high Pauli-like component, χ0, in their susceptibility (χ0 ≈ 2.22 × 10−4 emu/mol for NP and 5 × 10−4 emu/mol for NW). Moreover, for the NW s les, χ has a strong magnetic field dependence and presents a non-linear field-polarization feature, suggesting strong spin-orbit coupling.
Publisher: Elsevier BV
Date: 11-2000
Publisher: Elsevier BV
Date: 11-1997
Publisher: IOP Publishing
Date: 06-1997
Publisher: Elsevier BV
Date: 08-1997
Publisher: Elsevier BV
Date: 08-1997
Publisher: Elsevier BV
Date: 05-1998
Publisher: IOP Publishing
Date: 22-06-2001
Publisher: Elsevier BV
Date: 08-1997
Publisher: Elsevier BV
Date: 08-2022
DOI: 10.1016/J.SCITOTENV.2022.155021
Abstract: Continual application of nitrogen (N), phosphorous (P) and potassium (K) fertilizer may not return a profit to farmers due to the costs of application and the loss of NPK from soil in various ways. Thus, a combination of NPK granule with a porous biochar (termed here as BNPK) appears to offer multiple benefits resulting from the excellent properties of biochar. Given the lack of information on the properties of NPK and BNPK fertilizers, it is necessary to investigate the characteristics of both to achieve a good understanding of why BNPK granule is superior to NPK granule. Therefore, this study aims to investigate the characteristics of a maize straw biochar mixed with NPK granule, before and after application to soil, and compare them to those for a commercial NPK granule. The BNPK granule, with a greater surface area and porosity, showed a higher capacity to store and donate electrons than the NPK granule. Relatively lower concentrations of Ca, P, K, Si and Mg were dissolved from the BNPK, indicating the ability of the BNPK granule to maintain these mineral elements and reduce dissolution rate. To study the nutrient storage mechanism of the BNPK granule in the soil, short- and long-term leaching experiments were conducted. During the experiments, organo-mineral clusters, comprising C, P, K, Si, Al and Fe, were formed on the surface and inside the biochar pores. However, BNPK was not effective in reducing N leaching, in the absence of plants, in a red chromosol soil.
Publisher: IEEE
Date: 09-2019
Publisher: Elsevier BV
Date: 03-1998
Publisher: Elsevier BV
Date: 10-2015
Publisher: IOP Publishing
Date: 06-1997
Publisher: American Chemical Society (ACS)
Date: 05-01-2021
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 06-2005
Publisher: Informa UK Limited
Date: 06-1991
Publisher: Wiley
Date: 09-05-2014
DOI: 10.1118/1.4873679
Abstract: Due to the current interest in MRI-guided radiotherapy, the magnetic properties of the materials commonly used in radiotherapy are becoming increasingly important. In this paper, measurement results for the magnetization (BH) curves of a range of sintered heavy tungsten alloys used in radiation shielding and collimation are presented. Sintered heavy tungsten alloys typically contain >90% tungsten and <10% of a combination of iron, nickel, and copper binders. S les of eight different grades of sintered heavy tungsten alloys with varying binder content were investigated. Using a superconducting quantum interference detector magnetometer, the induced magnetic moment m was measured for each s le as a function of applied external field H0 and the BH curve derived. The iron content of the alloys was found to play a dominant role, directly influencing the magnetization M and thus the nonlinearity of the BH curve. Generally, the saturation magnetization increased with increasing iron content of the alloy. Furthermore, no measurable magnetization was found for all alloys without iron content, despite containing up to 6% of nickel. For two s les from different manufacturers but with identical quoted nominal elemental composition (95% W, 3.5% Ni, 1.5% Fe), a relative difference in the magnetization of 11%-16% was measured. The measured curves show that the magnetic properties of sintered heavy tungsten alloys strongly depend on the iron content, whereas the addition of nickel in the absence of iron led to no measurable effect. Since a difference in the BH curves for two s les with identical quoted nominal composition from different manufacturers was observed, measuring of the BH curve for each in idual batch of heavy tungsten alloys is advisable whenever accurate knowledge of the magnetic properties is crucial. The obtained BH curves can be used in FEM simulations to predict the magnetic impact of sintered heavy tungsten alloys.
Publisher: Elsevier BV
Date: 05-1998
Publisher: Elsevier BV
Date: 11-2002
Publisher: AIP Publishing
Date: 28-06-2021
DOI: 10.1063/5.0054063
Abstract: For the first time, the terahertz transmittance spectra of l-alanine have been measured using a single crystal. Measurements were obtained over a large temperature range (12–300 K) and revealed 18 absorptions between 20 and 250 cm−1. These modes were sharp and symmetric, a feature of single crystals and low temperatures. The spectra were directly compared to those of a powdered pellet s le. Raman spectroscopy and x-ray diffraction were used to confirm the s le’s structure and purity. With increasing temperature, all modes exhibit spectral redshift, well described by a Bose–Einstein model, indicating the phonon origin of the absorptions. The exceptions are the 91 and 128 cm−1 modes. The former blueshifts. The latter initially blueshifts but transitions to redshifting. Both behaviors are anomalous. Density-functional theory modeling helped assign all the observed modes.
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D0CP05432A
Abstract: Numerical calculations and experiments have identified large-scale molecular vibrations leading to unique terahertz spectral absorptions observed in dl -alanine.
Publisher: Elsevier BV
Date: 11-1989
Publisher: AIP Publishing
Date: 18-07-2003
DOI: 10.1063/1.1586467
Abstract: We investigated the effect of SiC nanoparticle doping on the crystal lattice structure, critical temperature Tc, critical current density Jc, and flux pinning in MgB2 superconductor. A series of MgB2−x(SiC)x/2 s les with x=0–1.0 were fabricated using an in situ reaction process. The contraction of the lattice and depression of Tc with increasing SiC doping level remained rather small most likely due to the counterbalancing effect of Si and C co-doping. The high level Si and C co-doping allowed the creation of intragrain defects and highly dispersed nanoinclusions within the grains which can act as effective pinning centers for vortices, improving Jc behavior as a function of the applied magnetic field. The enhanced pinning is mainly attributable to the substitution-induced defects and local structure fluctuations within grains. A pinning mechanism is proposed to account for different contributions of different defects in MgB2−x(SiC)x/2 superconductors.
Publisher: Royal Society of Chemistry (RSC)
Date: 2013
DOI: 10.1039/C3CP53667J
Abstract: Terahertz spectroscopy of RbBr reveals four prominent absorption lines at room temperature and a further 15 lines at 10 K. Via density-functional-theory (DFT) numerical modelling using the PBE0 hybrid GGA functional, all the absorptions are identified as correlated librations of water molecules in the RbBr lattice. Each libration mode is a combination of rocking, wagging and twisting motions of the water molecules. The number of libration lines and numerical modelling show that the C2v symmetry of water in RbBr is broken. Our modelling shows that the distribution of libration litudes and phases for different water molecules in the RbBr unit cell varies greatly between the different modes. All librational lines red-shift with increasing temperature. The rate of change for most lines is in the range 60-90 MHz K(-1) (or (2-3) × 10(-3) cm(-1) K(-1)). Two lines shift more rapidly with temperature, at rates of 240 and 300 MHz K(-1) (or (8 and 10) × 10(-3) cm(-1) K(-1)), respectively. Furthermore, the temperature dependence of the linewidth distinguishes two groups of lines. For one group, with weak linear temperature dependence of linewidth, cubic anharmonic terms in the RbBr crystal field are significant. This group is mainly associated with fully symmetric correlated librations. For the second group, with strong non-linear temperature dependence of the linewidth, quartic anharmonic terms in the RbBr crystal field are significant. However, the distribution of libration litudes, as well as the type of libration modes, influence the temperature dependence of the red shift, the linewidth, and the intensity, as well. Our combined experimental and theoretical investigation confirms the necessity of obtaining low-temperature data to observe all the calculated modes moreover, the richness of detail in the temperature dependence of the data invites further modelling spanning a range of temperatures.
Publisher: IEEE
Date: 08-2015
Publisher: Elsevier BV
Date: 02-1998
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 06-2005
Publisher: IEEE
Date: 09-2012
Publisher: IOP Publishing
Date: 02-02-2005
Publisher: IEEE
Date: 08-11-2020
Publisher: Elsevier BV
Date: 11-1999
Publisher: AIP Publishing
Date: 04-02-2002
DOI: 10.1063/1.1447010
Abstract: Transport critical current (Ic) was measured for Fe-sheathed MgB2 round wires. A critical current density of 5.3×104 A/cm2 was obtained at 32 K. Strong magnetic shielding by the iron sheath was observed, resulting in a decrease in Ic by only 15% in a field of 0.6 T at 32 K. In addition to shielding, interaction between the iron sheath and the superconductor resulted in a constant Ic between 0.2 and 0.6 T. This was well beyond the maximum field for effective shielding of 0.2 T. This effect can be used to substantially improve the field performance of MgB2/Fe wires at fields at least three times higher than the range allowed by mere magnetic shielding by the iron sheath. The dependence of Ic on the angle between field and current showed that the transport current does not flow straight across the wire, but meanders between the grains.
Publisher: Elsevier BV
Date: 11-2000
Publisher: SAGE Publications
Date: 05-2015
DOI: 10.1366/14-07658
Abstract: Terahertz spectroscopy of benzoic acid (BA) and two of its derivatives, 2-hydroxybenzoic acid (2OH-BA) and 3-hydroxyben-zoic acid (3OH-BA), has been investigated in the spectral region 200 to 500 cm −1 (6.06 to 15.15 THz). The spectra show distinct absorption features. There is agreement between some of the absorption lines observed for these compounds, despite a shift in energy, which is attributed to the differences in the molecular structures. Numerical modeling gave corresponding absorption lines, and this helped in the assignment. Temperature dependence studies revealed that most of the absorption lines are composite lines in this frequency region.
Publisher: AIP Publishing
Date: 22-07-2002
DOI: 10.1063/1.1497712
Abstract: Smooth modulation structure of Mg–B alloy in the quenched reaction product of Mg and amorphous B was studied. It indicates that the MgB2 formed possibly in spinodal decomposition, thus resulting in MgB2 nanodomains. It was found that the nanodomains with small angle boundaries of atomic-scale width were distributed within the subgrains that constitute the clusters in MgB2 grains. This nanostructural characteristic may be intrinsic in the quenched reaction product of Mg and amorphous B. It makes the nanodomain boundaries not act as barriers to the current percolation path, thus exhibiting no weak-link problem in the MgB2.
Publisher: IOP Publishing
Date: 23-08-2011
Publisher: Springer Science and Business Media LLC
Date: 1999
Publisher: AIP Publishing
Date: 04-10-2004
DOI: 10.1063/1.1790069
Abstract: High-quality bulk MgB2 exhibits a structure of voids and agglomeration of crystals on different length scales. Because of this, the superconducting currents percolate between the voids in the ensuing structure. Magnetic measurements reveal that the superconducting currents circulate on at least three different length scales, of ∼1μm, ∼10μm, and whole of the s le (∼millimeter). Each of these screenings contributes to the measured irreversible magnetic moment (Δm). The analysis of the field dependence of Δm for s les of subsequently decreasing size showed that the critical current obtained using the simple critical state model is erroneous. This leads to the artifact of the s le size-dependent critical current density Jc and irreversibility field. Our data analysis enables the separation of the contribution of each of the screening currents to Δm. The field dependence of each of the currents follows a stretched exponential form. The currents flowing around whole of the s le give a dominant contribution to Δm in the intermediate fields (1T& H& T at 20K) and they can be used to obtain the value of Jc from critical state model, which corresponds to the transport Jc. The stretched exponential field dependence of these currents is similar to the one obtained for high-temperature superconductors, and it seems to be connected with the percolation of the currents.
Publisher: Walter de Gruyter GmbH
Date: 27-06-2017
Abstract: Nanobiotechnology is an immensely potential invention, which is expected to bring about revolutionary changes in many aspects of essential human needs including medical treatments and foods. Although the technology has passed through its embryonic stage, its medical applications in preparing and delivering drugs to target cells of human bodies to cure incurable diseases are still under scientific scrutiny. A 2007 study suggests that Australia needs to have a review of its regulatory framework for nanotechnology by 2017. This article examines the current regulation of nanotechnology and its medical applications in Australia, and observes that it would be premature to impose any stringent regulation at this stage on medical experimentations. We are of the view that an excessively precautionary policy may hinder further research, which is critical to discovering the benefit and harm with certainty. Hence, in the greater interest of the facilitation of research and affirmation of benefits of this technology, we recommend that adopting a hybrid regulatory method composed of self-regulation and accommodating government regulation would be an appropriate policy approach to the regulation of nanobiotechnology. We also accept the need for a set of internationally harmonized policy principles to guide our actions in relation to this technology.
Publisher: Elsevier BV
Date: 11-1990
Publisher: IOP Publishing
Date: 03-10-2012
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 06-2003
Publisher: Elsevier BV
Date: 08-2005
Publisher: AIP Publishing
Date: 19-03-2007
DOI: 10.1063/1.2715026
Abstract: Correlation of upper critical field (Hc2) and critical current density (Jc) with processing temperature of nano-C doped MgB2 has been studied in comparison to SiC and pure MgB2. SiC and C doped MgB2 exhibit opposite trends in the dependence of Jc and Hc2 on sintering temperature. This is explained by different reactivities of carbon available upon creation of MgB2 for the two types of doping. Nanocarbon doped MgB2 requires sintering temperatures in excess of 900°C to obtain high boron substitution for carbon, enhancing the vortex pinning and impurity scattering of charge carriers. However, carbon substitution in nano-SiC doped MgB2 occurs at less than 650°C, allowing lower sintering temperature and high degree of carbon substitution. Both pure and SiC doped MgB2 benefit from low sintering temperature, which results in more grain boundary defects. Substantial carbon substitution can compensate for the disadvantage of sintering at high temperature of nano-C doped MgB2, giving the best Jc of 4.8×103A∕cm2 at 4.5K and 12T. This is comparable to the low-temperature sintered nano-SiC doped MgB2 wires.
Publisher: IOP Publishing
Date: 17-01-2006
Publisher: Elsevier BV
Date: 06-1998
Publisher: Springer Science and Business Media LLC
Date: 17-07-2015
DOI: 10.1007/S00249-015-1059-0
Abstract: Liposomal drug delivery systems (LDDSs) are promising tools used for the treatment of diseases where highly toxic pharmacological agents are administered. Currently, destabilising LDDSs by a specific stimulus at a target site remains a major challenge. The bacterial mechanosensitive channel of large conductance (MscL) presents an excellent candidate biomolecule that could be employed as a remotely controlled pore-forming nanovalve for triggered drug release from LDDSs. In this study, we developed superparamagnetic nanoparticles for activation of the MscL nanovalves by magnetic field. Synthesised CoFe2O4 nanoparticles with the radius less than 10 nm were labelled by SH groups for attachment to MscL. Activation of MscL by magnetic field with the nanoparticles attached was examined by the patch cl technique showing that the number of activated channels under r pressure increased upon application of the magnetic field. In addition, we have not observed any cytotoxicity of the nanoparticles in human cultured cells. Our study suggests the possibility of using magnetic nanoparticles as a specific trigger for activation of MscL nanovalves for drug release in LDDSs.
Publisher: Elsevier BV
Date: 09-2007
Publisher: IOP Publishing
Date: 02-2008
Publisher: IOP Publishing
Date: 19-08-2004
Publisher: Wiley
Date: 20-06-2008
Abstract: Flute-like porous alpha-Fe2O3 nanorods and branched nanostructures such as pentapods and hexapods were prepared through dehydration and recrystallisation of hydrothermally synthesised beta-FeOOH precursor. Transmission electron microscopy (TEM), high-resolution TEM and selected area electron diffraction analyses reveal that the nanorods, which grow along the [110] direction, have nearly hollow cavities and porous walls with a pore size of 20-50 nm. The hexapods have six symmetric arms with a diameter of 60-80 nm and length of 400-900 nm. The growth direction of the arms in the hexapod-like nanostructure is also along the [110] direction, and there is a dihedral angle of 69.5 degrees between adjacent arms. These unique iron oxide nanostructures offer the first opportunity to investigate their magnetic and gas sensing properties. The nanostructures exhibited unusual magnetic behaviour, with two different Morin temperatures under field-cooled and zero-field-cooled conditions, owing to their shape anisotropy and magnetocrystalline anisotropy. Furthermore, the alpha-Fe2O3 nanostructures show much better sensing performance towards ethanol than that of the previously reported polycrystalline nanotubes. In addition, the alpha-Fe2O3 nanostructure based sensor can selectively detect formaldehyde and acetic acid among other toxic, corrosive and irritant vapours at a low working temperature with rapid response, high sensitivity and good stability.
Publisher: American Physical Society (APS)
Date: 02-1997
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 03-2001
DOI: 10.1109/77.919920
Publisher: Elsevier BV
Date: 11-2000
Publisher: Elsevier BV
Date: 03-1991
Publisher: American Physical Society (APS)
Date: 22-05-2002
Publisher: IOP Publishing
Date: 10-12-2002
Publisher: AIP Publishing
Date: 10-12-2003
DOI: 10.1063/1.1634378
Abstract: The effect of doping MgB2 with carbon nanotubes on transition temperature, lattice parameters, critical current density and flux pinning was studied for MgB2−xCx with x=0, 0.05, 0.1, 0.2, and 0.3. The carbon substitution for B was found to enhance Jc in magnetic fields but depress Tc. The depression of Tc, which is caused by the carbon substitution for B, increases with an increasing doping level, sintering temperature, and duration. By controlling the extent of the substitution and addition of carbon nanotubes we can achieve the optimal improvement on critical current density and flux pinning in magnetic fields while maintaining the minimum reduction in Tc. Under these conditions, Jc was enhanced by two orders of magnitude at 8 T and 5 K and 7 T and 10 K. Jc was more than 10 000 A/cm2 at 20 K and 4 T and 5 K and 8.5 T, respectively.
Publisher: Springer Science and Business Media LLC
Date: 20-07-2019
Publisher: American Physical Society (APS)
Date: 08-1998
Publisher: MDPI AG
Date: 29-09-2016
Publisher: IOP Publishing
Date: 10-1998
Publisher: American Physical Society (APS)
Date: 29-08-2003
Publisher: Elsevier BV
Date: 1997
Publisher: American Physical Society (APS)
Date: 19-08-2014
Publisher: Elsevier BV
Date: 08-2004
Publisher: American Chemical Society (ACS)
Date: 07-01-2015
DOI: 10.1021/JP5052134
Abstract: Previous THz spectroscopy of the TNT explosive precursor, 2,4-dinitrotoluene (DNT), has been restricted to room temperature (apart from one set of data at 11 K). Here, for the first time, we investigate the spectrum as the temperature is systematically varied, from 7 to 245 K. Many new features appear in the spectrum on cooling below room temperature. As well as the five absorption lines observed previously, we observe five additional lines. In addition, a new room-temperature line at 8.52 THz (281 cm(-1)) is observed. Six of the lines red-shift with temperature and four of them blue-shift. The blue shift is explained by interplay between intramolecular and intermolecular hydrogen bonds. The variation in line width and line intensity with temperature is not systematic, although a conspicuous decrease in line intensity with temperature is observed in all cases. Modeling with hybrid PBE0 and TPSSh functionals helps identify absorption modes.
Publisher: Elsevier BV
Date: 03-1992
Publisher: American Chemical Society (ACS)
Date: 15-10-2010
DOI: 10.1021/JP102286E
Publisher: Elsevier BV
Date: 04-2002
Publisher: AIP Publishing
Date: 13-11-2006
DOI: 10.1063/1.2388126
Abstract: A magnetic field of up to 12T was applied during the sintering process of pure MgB2 and carbon nanotube (CNT) doped MgB2 wires. The authors have demonstrated that magnetic field processing results in grain refinement, homogeneity, and enhancement in Jc(H) and Hirr. The extent of improvement in Jc increases with increasing field. The Jc for a 10T field processed CNT doped s le increases by a factor of 3 at 10K and 8T and at 20K and 5T, respectively. Hirr for the 10T field processed CNT doped s le reached 9T at 20K, which exceeded the best value of SiC doped MgB2 at 20K. Magnetic field processing reduces the resistivity in CNT doped MgB2, straightens the entangled CNTs, and improves the adherence between CNTs and the MgB2 matrix.
Publisher: American Physical Society (APS)
Date: 06-2023
Publisher: Elsevier BV
Date: 02-2004
Publisher: Elsevier BV
Date: 11-1998
Publisher: IEEE
Date: 09-2016
Publisher: Elsevier BV
Date: 09-2001
Publisher: American Chemical Society (ACS)
Date: 29-06-2016
Abstract: Dramatic changes in molecular structure, degradation pathway, and porosity of biochar are observed at pyrolysis temperatures ranging from 250 to 550 °C when bamboo biomass is pretreated by iron-sulfate-clay slurries (iron-clay biochar), as compared to untreated bamboo biochar. Electron microscopy analysis of the biochar reveals the infusion of mineral species into the pores of the biochar and the formation of mineral nanostructures. Quantitative (13)C nuclear magnetic resonance (NMR) spectroscopy shows that the presence of the iron clay prevents degradation of the cellulosic fraction at pyrolysis temperatures of 250 °C, whereas at higher temperatures (350-550 °C), the clay promotes biomass degradation, resulting in an increase in both the concentrations of condensed aromatic, acidic, and phenolic carbon species. The porosity of the biochar, as measured by NMR cryoporosimetry, is altered by the iron-clay pretreatment. In the presence of the clay, at lower pyrolysis temperatures, the biochar develops a higher pore volume, while at higher temperature, the presence of clay causes a reduction in the biochar pore volume. The most dramatic reduction in pore volume is observed in the kaolinite-infiltrated biochar at 550 °C, which is attributed to the blocking of the mesopores (2-50 nm pore) by the nonporous metakaolinite formed from kaolinite.
Publisher: Springer Science and Business Media LLC
Date: 07-02-2017
Publisher: IOP Publishing
Date: 13-03-2008
Publisher: Elsevier BV
Date: 07-1990
Publisher: IEEE
Date: 29-08-2021
Publisher: Elsevier BV
Date: 05-2017
Publisher: Elsevier BV
Date: 04-1990
Publisher: Elsevier BV
Date: 04-2002
Publisher: Springer Science and Business Media LLC
Date: 08-01-2021
DOI: 10.1038/S41598-020-80377-Z
Abstract: Application of iron (Fe)- and silica (Si)-enhanced biochar compound fertilisers (BCF) stimulates rice yield by increasing plant uptake of mineral nutrients. With alterations of the nutrient status in roots, element homeostasis (e.g., Fe) in the biochar-treated rice root was related to the formation of biominerals on the plaque layer and in the cortex of roots. However, the in situ characteristics of formed biominerals at the micron and sub-micron scale remain unknown. In this study, rice seedlings ( Oryza sativa L. ) were grown in paddy soil treated with BCF and conventional fertilizer, respectively, for 30 days. The biochar-induced changes in nutrient accumulation in roots, and the elemental composition, distribution and speciation of the biomineral composites formed in the biochar-treated roots at the micron and sub-micron scale, were investigated by a range of techniques. Results of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) showed that biochar treatment significantly increased concentrations of nutrients (e.g., Fe, Si, and P) inside the root. Raman mapping and vibrating s le magnetometry identified biochar particles and magnetic Fe nanoparticles associated with the roots. With Fe plaque formation, higher concentrations of FeO x − and FeO x H − anions on the root surface than the interior were detected by time-of-flight secondary ionization mass spectrometry (ToF-SIMS). Analysis of data from scanning electron microscopy energy-dispersive spectroscopy (SEM-EDS), and from scanning transmission electron microscopy (STEM) coupled with EDS or energy electron loss spectroscopy (EELS), determined that Fe(III) oxide nanoparticles were accumulated in the crystalline fraction of the plaque and were co-localized with Si and P on the root surface. Iron-rich nanoparticles (Fe–Si nanocomposites with mixed oxidation states of Fe and ferritin) in the root cortex were identified by using aberration-corrected STEM and in situ EELS analysis, confirming the biomineralization and storage of Fe in the rice root. The findings from this study highlight that the deposition of Fe-rich nanocomposites occurs with contrasting chemical speciation in the Fe plaque and cortex of the rice root. This provides an improved understanding of the element homeostasis in rice with biochar-mineral fertilization.
Publisher: Wiley
Date: 16-02-1992
Publisher: Elsevier BV
Date: 03-2001
Start Date: 07-2006
End Date: 12-2008
Amount: $20,000.00
Funder: Australian Research Council
View Funded ActivityStart Date: 2010
End Date: 12-2013
Amount: $580,000.00
Funder: Australian Research Council
View Funded ActivityStart Date: 11-2009
End Date: 12-2012
Amount: $385,000.00
Funder: Australian Research Council
View Funded ActivityStart Date: 05-2002
End Date: 12-2007
Amount: $1,087,891.00
Funder: Australian Research Council
View Funded ActivityStart Date: 04-2014
End Date: 12-2017
Amount: $410,000.00
Funder: Australian Research Council
View Funded ActivityStart Date: 2009
End Date: 12-2012
Amount: $300,000.00
Funder: Australian Research Council
View Funded ActivityStart Date: 2011
End Date: 12-2012
Amount: $360,000.00
Funder: Australian Research Council
View Funded ActivityStart Date: 04-2011
End Date: 12-2011
Amount: $490,000.00
Funder: Australian Research Council
View Funded ActivityStart Date: 04-2008
End Date: 06-2009
Amount: $300,000.00
Funder: Australian Research Council
View Funded ActivityStart Date: 2009
End Date: 12-2009
Amount: $857,230.00
Funder: Australian Research Council
View Funded ActivityStart Date: 2007
End Date: 12-2008
Amount: $400,000.00
Funder: Australian Research Council
View Funded ActivityStart Date: 2008
End Date: 12-2008
Amount: $340,000.00
Funder: Australian Research Council
View Funded Activity