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microscopy Observations of Habitable Space in Biochar for Colonization by Fungal Hyphae From Soil

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Journal of Integrative Agriculture 2014年第3期13卷 483-490页

作者： Noraini m Jaafar Peta l Clode lynette K Abbott Soil Biology and molecular Ecology Group School of Earth and Environment and UWA Institute of Agriculture The University of Western Australia Department of land management Faculty of Agriculture Universiti Putra Malaysia Centre for microscopy Characterisation and Analysis The University of Western Australia

Biochar is a potential micro-environment for soil microorganisms but evidence to support this suggestion is limited. We explored imaging techniques to visualize and quantify fungal colonization of habitable spaces in a biochar made from a woody feedstock. In addition to characterization of the biochar, it was necessary to optimize preparation and observation methodologies for examining fungal colonization of the biochar. Biochar surfaces and pores were investigated using several microscopy techniques. Biochar particles were compared in soilless media and after deposition in soil. Scanning electron microscopy （SEm） observations and characterization of the biochar demonstrated structural heterogeneity within and among biochar particles. Fungal colonization in and on biochar particles was observed using light, fluorescence and electron microscopy. Fluorescent brightener RR 2200 was more effective than Calcofluor White as a hyphal stain. Biochar retrieved from soil and observed using fluorescence microscopy exhibited distinct hyphal networks on external biochar surfaces. The extent of hyphal colonization of biochar incubated in soil was much less than for biochar artificially inoculated with fungi in a soilless medium. The location of fungal hyphae was more clearly visible using SEm than with fluorescence microscopy. Observations of biochar particles colonized by hyphae from soil posed a range of difficulties including obstruction by the presence of soil particles on biochar surfaces and inside pores. Extensive hyphal colonization of the surface of the biochar in the soilless medium contrasted with limited hyphal colonization of pores within the biochar. Both visualization and quantification of hyphal colonization of surfaces and pores of biochar were restricted by two-dimensional imaging associated with uneven biochar surfaces and variable biochar pore structure. There was very little colonization ofbiochar from hyphae in the agricultural soil used in this study.

关键词： biochar agriculture fungi soil habitable pore space microscopy

On Absolute N?rlund Spaces and matrix Operators

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Acta mathematica Sinica,English Series 2018年第5期34卷 812-826页

作者： G.Canan HAZAR m.Ali SARIG?l Department of mathematics Faculty of Science and Arts Pamukkale University

In a more recent paper, the second author has introduced a space ｜Cα｜k as the set of all series by absolute summable using Cesaro matrix of order α 〉 -1. In the present paper we extend it to the absolute NSrlund space ｜Np^θ｜k taking Norlund matrix in place of Cesaro matrix, and also examine some topological structures, α-β-γ-duals and the Schauder base of this space. Further we characterize certain matrix operators on that space and determine their operator norms, and so extend some well-known results.

关键词： Sequence spaces absolute Norlund summability dual spaces matrix transformations bounded linear operator BK spaces

A note on the numerical simulations of flow past a wavy square-section cylinder

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Acta mechanica Sinica 2008年第1期24卷 101-105页

作者： G. C. ling l. m. lin The State Key laboratory of Nonlinear mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

The flow past a square-section cylinder with a geometric disturbance is investigated by numerical simulations. The extra terms, due to the introduction of mapping transformation simulating the effect of disturbance into the transformed Navier-Stokes equations, are correctly derived, and the incorrect ones in the previous literature are pointed out and analyzed. Furthermore, the relationship between the vorticity, especially on the cylinder surface, and the disturbance is derived and explained theoretically. The computations are performed at two Reynolds numbers of 100 and 180 and three amplitudes of waviness of 0.006, 0.025 and 0.167 with another aim to explore the effects of different Reynolds numbers and disturbance on the vortex dynamics in the wake and forces on the body. Numerical results have shown that, at the mild waviness of 0.025, the Kairmain vortex shedding is suppressed completely for Re = 100, while the forced vortex dislocation is appeared in the near wake at the Reynolds number of 180. The drag reduction is up to 21.6% at Re = 100 and 25.7% at Re = 180 for the high waviness of 0.167 compared with the non-wavy cylinder. The lift and the Strouhal number varied with different Reynolds numbers and the wave steepness are also obtained.

关键词： Numerical simulation. Geometric disturbance.Square-section cylinder Wake flow

Synthesis and crystal structure of a neodymium coordination polymer with 2,6-anthraquinonedisulfonate

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Particuology 2010年第3期8卷 221-224页

作者： Jennifer l. Nicholls John Bacsa Andrew m. Fogg Department of Chemistry University of Liverpool Crown Street Liverpool L69 7ZD United Kingdom

The coordination polymer, （Nd（H2O）5）2（2,6-AQDS）3.2H2O where 2,6-AQDS = 2,6- anthraquinonedisulfonate, has been synthesised via a hydrothermal route. Structurally, it consists of layers of monomeric Nd polyhedra which are linked by 2,6-AQDS anions forming a polymeric, three-dimensional network. Each Nd atom is nine coordinate, bonding to five water molecules and to four oxygen atoms from four 2,6-AODS anions which in turn pillar the layers by bridging two Nd atoms in one layer, and coordinating to a single Nd in the other.

关键词： lanthanide layered materials Sulfonate Coordination polymer

Soliton Trains Induced by Adaptive Shaping with Periodic Traps in Four-level Ultracold Atom Systems

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Communications in Theoretical Physics 2017年第6期67卷 667-673页

作者： m.l.Djouom Tchenkoue D.Welakuh mbangheku Alain m.Dikandé laboratory of Research on Advanced materials and Nonlinear Sciences Department of PhysicsFaculty of ScienceUniversity of Buea

It is well known that an optical trap can be imprinted by a light field in an ultracold-atom system embedded in an optical cavity, and driven by three different coherent fields. Of the three felds coexisting in the optical cavity there is an intense control field that induces a giant Kerr nonlinearity via electromagnetically-induced transparency, and another feld that creates a periodic optical grating of strength proportional to the square of the associated Rabi frequency. In this work elliptic-soliton solutions to the nonlinear equation governing the propagation of the probe field are considered, with emphasis on the possible generation of optical soliton trains forming a discrete spectrum with well defined quantum numbers. The problem is treated assuming two distinct types of periodic optical gratings and taking into account the negative and positive signs of detunings （detuning above or below resonance）. Results predict that the competition between the self-phase and cross-phase modulation nonlinearities gives rise to a rich family of temporal soliton train modes characterized by distinct quantum numbers.

关键词： temporal soliton trains Jacobi Elliptic functions electromagnetically-induced transparency tiJur-level ultracold-atom systems

AC-electronic and dielectric properties of semiconducting phthalocyanine compounds: a comparative study

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Journal of Semiconductors 2013年第11期34卷 1-6页

作者： Safa’a m.Hraibat Rushdi m-l.Kitaneh mohammad m.Abu- Samreh Abdelkarim m.Saleh Al-Quds University Physics Dept.Abu DeesJerusalem P.O.Box 20002 Palestine via Israel

The AC-electronic and dielectric properties of different phthalocyanine films （ZnPc, CuPc, FePc, and H2Pc） were investigated over a wide range of temperature. Both real and imaginary parts of the dielectric constant （ε = ε1 - ε2） were found to be influenced by temperature and frequency. Qualitatively the behavior was the same for those compounds; however, the central atom, film thickness, and the electrode type play an important role in the variation of their values. The relaxation time, r, was strongly frequency-dependent at all temperatures and low frequencies, while a weak dependency is observed at higher frequencies. The relaxation activation energy was derived from the slopes of the fitted lines of In r and the reciprocal of the temperature （l/T）. The values of the activation energy were accounted for the hopping process at low temperatures, while a thermally activated conduction process was dominant at higher temperatures. The maximum barrier height, Wm, was found to be temperature and frequency dependent for all phthalocyanine compounds. The value Wm depends greatly on the nature of the central atom and electrode material type. The correlated barrier hopping model was found to be the appropriate mechanism to describe the charge carrier＇s transport in phthalocyanine films.

关键词： dielectric function organic semiconductor phthalocyanine relaxation time

Accelerating bainite transformation by concurrent pearlite formation in a medium mn steel:Experiments and modelling

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Journal of materials Science & Technology 2024年第9期176卷 211-223页

作者： l.K.Huang F.liu m.X.Huang Department of mechanical Engineering The University of Hong KongPokfulam RoadHong KongChina State Key laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’anShaanxi710072China

Bainite transformation has yet to be utilized and even thoroughly studied in medium mn ***,we investigate the isothermal bainite transformation in a 10mn steel at 450°C experimentally and theoretically,focusing on the effect of dislocations introduced by warm *** show that the bainite transformation in the studied medium mn steel exhibits extremely sluggish kinetics(on a time scale of days),concurrent with the pearlite *** introduced dislocations can significantly accelerate bainite transformation kinetics while also facilitating the pearlite *** is likely the first report on the simultaneous occurrence of these two solid-state reactions in medium mn *** respect to the roles of dislocations in the acceleration of bainite transformation observed in this work,we propose a new‘carbon depletion mechanism’,in which dislocations-stimulated pearlite formation makes a twofold contribution:facilitating the formation of bainitic ferrite sub-units to further enhance the autocatalytic effect and preventing the carbon enrichment in the remaining *** this basis,a physical model is developed to quantitatively understand the bainite transformation kinetics considering the effect of concurrent pearlite formation,revealing good agreements between model descriptions and experiment *** findings,herein,offer fundamental insights into the bainite transformation in medium mn steels and uncover a previously unidentified role played by introduced dislocations in influencing the kinetics of bainite formation,which may guide its future application in manipulating microstructure for the development of advanced high-strength steels.

关键词： medium mn steels Bainite Thermodynamics Kinetics Phase transformation

Isolation of a salt tolerant laccase secreting strain of Trichoderma sp. NFCCI-2745 and optimization of culture conditions and assessing its efectiveness in treating saline phenolic efuents

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Journal of Environmental Sciences 2013年第12期25卷 2410-2416页

作者： l.m.Divya G.K.Prasanth C.Sadasivan Department of Biotechnology and microbiology Kannur University

most of the hazardous pollutants are phenolic in nature and persists in the environment. The ability of laccases to oxidize phenolic compounds and reduce molecular oxygen to water has led to intensive studies of these enzymes. Therefore the fungal strains with high laccase activity and substrate affinity that can tolerate harsh environmental conditions have a potential for biotechnological applications. Salt tolerant laccase secreting fungi can be utilized in treatment of saline and phenolic rich industrial effluents such as coir effluent and textile effluent that needed to be diluted several fold before microbial treatment. This is the first study describing the isolation and optimization of a salt tolerant strain of Trichoderma sp. potential for industrial applications. The fungus was identified based on morphological characteristics and was subsequently confirmed with molecular techniques and deposited at National Fungal Culture Collections of India （NFCCI） under the Accession No. Trichoderma viride NFCCI 2745. In contrast to other laccase secreting fungi, light conditions did not exert much influence on laccase production of this strain and salinity enhanced its laccase secretion. The fungus effectively removed the phenolic content of the textile effluent, coir-ret liquor and wood processing effluent within 96 hr of incubation. The tolerance of the fungus to high salinity and phenolic compounds makes this strain ideal for treating saline and phenolic rich industrial effluents.

关键词： laccase optimization phenol tolerant salt tolerant Trichoderma viride

Fate and transport of theβ-adrenergic agonist ractopamine hydrochloride in soil–water systems

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Journal of Environmental Sciences 2016年第7期28卷 40-48页

作者： Heldur Hakk Weilin l.Shelver Francis X.m.Casey USDA-ARS Biosciences Research laboratory 1605 Albrecht Blvd.FargoND 58102USA Department of Soil Sciences North Dakota State UniversityAlbrecht Blvd.FargoND 58108USA

The feed additive ractopamine hydrochloride was fortified at four concentrations into batch vials containing soils that differed in both biological activity and organic matter（Om）.Sampling of the liquid layer for 14 days demonstrated that ractopamine rapidly dissipated from the liquid layer. less than 20% of the fortified dose remained in the liquid layer after 4 hr,and recoveries of dosed ractopamine ranged from 8 to 18% in the liquid layer at 336 hr. Sorption to soil was the major fate for ractopamine in soil：water systems, i.e., 42%–51% of the dose at14 days. The major portion of the sorbed fraction was comprised of non-extractables; a smaller fraction of the sorbed dose was extracted into water and acetone, portions which would be potentially mobile in the environment. Partitioning coefficients for all soils suggested strong sorption of ractopamine to soil which is governed by hydrophobic interactions and cation exchange complexes within the soil Om. Ractopamine degradation was observed, but to mostly non-polar compounds which had a higher potential than ractopamine to sorb to soil. The formation of volatiles was also suggested. Therefore, despite rapid and extensive soil sorption,these studies indicated a portion of ractopamine, present in manures used to fertilize soils,may be mobile in the environment via water-borne events.

关键词： Ractopamine Transport Degradation β-Adrenergic agonist Soil