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Impacts of.wastewater sludge amendments in restoring nitrogen cycle in p-nitrophenol contaminated soil

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Journal of.Environmental Sciences 2011年第4期23卷 616-623页

作者： f. Olcay Topac Sagban Department of.Environmental Engineering Uludag University

The possible impacts on nitrogen-cycle in a p-nitrophenol （PNP） polluted soil and the ef.ectiveness of.wastewater sludge amendments in restoring nitrif.cation potential and urease activity were evaluated by an incubation study. The results indicated that PNP at 250 mg/kg soil inhibited urease activity, nitrif.cation potential, arginine ammonif.cation rate and heterotrophic bacteria counts to some extents. Af.er exposure to PNP, the nitrif.cation potential of.the tested soil was dramatically reduced to zero over a period of.30 days. Based on the f.ndings, nitrif.cation potential was postulated as a simple biochemical indicator f.r PNP pollution in soils. Nitrogen-cycling processes in soils responded positively to the applications of.wastewater sludges. A sludge application rate of.200 tons/ha was suf.icient f.r successf.l biostimulation of.these nitrogen processes. The microbial activities in sludge-amended, heavy PNP-polluted soils seemed to recover af.er 30–45 days, indicating the ef.ectiveness of.sludge as a usef.l soil amendment.

关键词： p-nitrophenol wastewater sludge soil pollution nitrogen-cycle biostimulation

Calcium-mediated paired pulse depression in juvenile rat dorsal striatum

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Neural Regeneration Research 2012年第10期7卷 772-777页

作者： Yuf.ng Xie Michael f. Jackson John f. MacDonald Robarts Research Institute University of Western Ontario London Ontario Canada Department of.Physiology and Pharmacology University of Western Ontario London Ontario Canada Department of.Anatomy and Cell Biology University of Westem Ontario London Ontario Canada

As the major division of.the basal ganglia, neostriatum f.rms mutual connections with multiple brain areas and is critically involved in motor control and learning/memory. Long-term synaptic plasticity has been widely studied in dif.erent species recently. However, there are rare reports about the short-term synaptic plasticity in neostratium. In the present study, using f.eld excitatory postsynaptic potentials recording, we reported one f.rm of.short-term synaptic plasticity that is paired pulse depression in juvenile rat dorsal striatum slices induced by stimuli of.the white matter. The f.eld excitatory postsynaptic potentials could be abolished by α-amino-3-hydroxy-5-methylizoxazole-4-propionic acid receptor antagonist, 6-cyano-7-nitroquinoxaline-2,3-dione, but not by gamma-aminobutyric acid type A receptor antagonist bicuculline or dopamine D1 receptor antagonist SKf.81297. The paired pulse depression in the corticostratial pathway was dif.erent f.om paired pulse f.cilitation in the hippocampal CA1 synapse. In addition, the paired pulse depression was not af.ected by bath application of.gamma-aminobutyric acid type A receptor antagonist or dopamine D1 receptor antagonist. However, low calcium and high magnesium could attenuate the paired pulse depression. These f.ndings suggest a more complicated plasticity f.rm in the dorsal striatum of.juvenile rats that is dif.erent f.om that in the hippocampus, which is related with extracellular calcium.

关键词： paired pulses depression dorsal striatum calcium juvenile rats

Uncertainty relations f.r general phase spaces

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f.ontiers of.physics 2016年第3期11卷 51-60页

作者： Reinhard f. Werner Institut f.ir Theoretische Physik Leibniz Universitiit Hannover Germany

We describe a setup f.r obtain!ing uncertainty relations f.r arbitrary pairs of.observables related by a f.urier transf.rm. The physical examples discussed here are the standard position and momentum, number and angle, f.nite qudit systems, and strings of.qubits f.r quantum inf.rmation applications. The uncertainty relations allow f.r an arbitrary choice of.metric f.r the outcome distance, and the choice of.an exponent distinguishing, e.g., absolute and root mean square deviations. The emphasis of.this article is on developing a unif.ed treatment, in which one observable takes on values in an arbitrary locally compact Abelian group and the other in the dual group. In all cases, the phase space symmetry implies the eciuality of.measurement and preparation uncertainty bounds. There is also a straightf.rward method f.r determining the optimal bounds.

关键词： uncertainty relations phase space measurement uncertainty

Kinetics of.the Reaction of.2-Chloro-3,5-dinitrobenzotrif.ouride with Aniline in Toluene and Methanol-Toluene Mixed Solvents

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Chinese Journal of.Chemistry 2012年第1期30卷 109-114页

作者： f.thalla Magda f. Chemistry Department Faculty of ScienceAlexandria UniversityP.O.426 IbrahimiaAlexandria 21321Egypt

Kinetics of.the reaction of.2-chloro-3,5-dinitrobenzotrif.ouride with aniline were studied in toluene, metha- nol-toluene binary solvents, benzene and chlorof.rm. The reaction in toluene exhibits third-order kinetics consistent with aggregates of.aniline. Thermodynamic parameters AH#, AS# and AG# are calculated and discussed f.r the reaction of.2-chloro-3,5-dinitrobenzotrif.ouride with aniline in methanol-toluene. Molecular complexes between aniline and the substrate are rejected spectrophotometricaly. The mechanism is studied and compared with the reac- tion in presence of.pyridine. It shows an amine dependence and f.rmation of.homo and/or hetero mixed aggregates between aniline and pyridine i.e. dimer mechanism.

关键词： kinetics 2-chloro-3,5-dinitrobenzotrif.ouride methanol-toluene

Early stages of.non-classic crystal growth

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Science China Chemistry 2011年第12期54卷 1867-1876页

作者： GREER Heather f. EaStChem School of ChemistryUniversity of St Andrews

Investigation of.early stages of.crystal growth revealed that crystal growth in some systems may not f.llow the classic *** the early stages of.inorganic crystal growth,precursor molecules and/or nanocrystallites may aggregate into large and disordered particles with the assistance of.some polymers or *** crystallization of.these aggregates would then take place to f.rm shells with high crystallinity and density,f.llowed by an extension of.the crystallization f.om surf.ce to *** so-called reversed crystal growth mechanism has been f.und in crystallization of.several inorganic compounds including zeolites,perovskites,metals and metal oxides,and will be identif.ed in more material *** establishment of.this new crystal growth route gave us more f.eedom to control the morphology of.crystals and to understand the f.rmation mechanism of.many natural *** article gives a brief.review of.the recent research in this f.eld by f.aturing some typical examples of.the reversed crystal growth.

关键词： reversed crystal growth hollow crystals core-shell particles electron microscopy

Multiscale stochastic f.nite element method on random f.eld modeling of.geotechnical problems- a f.st computing procedure

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f.ontiers of.Structural and Civil Engineering 2015年第2期9卷 107-113页

作者： Xi f. XU School of.Civil Engineering Beo'ing Jiaotong University Beijing 100044 China

The Green-f.nction-based multiscale stochastic f.nite element method (MSf.M) has been f.rmulated based on the stochastic variational principle. In this study a f.st computing procedure based on the MSf.M is developed to solve random f.eld geotechnical problems with a typical coef.icient of.variance less than 1. A unique f.st computing advantage of.the procedure enables computation perf.rmed only on those locations of.interest, theref.re saving a lot of.computation. The numerical example on soil settlement shows that the procedure achieves signif.cant computing ef.iciency compared with Monte Carlo method.

关键词： multiscale f.nite element settlement perturbation random f.eld geotechnical

f.rtif.cation Challenges and Needs

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Biomedical and Environmental Sciences 2001年第1期14卷 98-103页

作者： RODOLf. f. f.ORENTINO President Philippine Association of Nutrition Philippines

Experience in many parts of.the developing world has shown that f.od f.rtif.cation of.ers a cost_ef.ective and sustainable solution to the problem of.micronutrient malnutrition. Building on the advances in science and technology and backed by studies on the economic benef.ts of.f.rtif.cation programs, governments and industry are beginning to respond positively to the call of.nutrition advocates to adopt f.rtif.cation as a long_term strategy. On the other hand, f.rmidable challenges still remain in many countries in Asia, constraining the widespread adoption of.this strategy. The science and technology community needs to provide adequate scientif.c and technological inf.rmation as basis f.r planning and decision making. The government f.ces the challenge of.providing the enabling environment f.r all stakeholders to cooperate in the f.rtif.cation ef.ort. Industry f.ces the challenge of.adapting its production system to the requirements of.f.rtif.cation in order that they can contribute to social objectives while pursuing their economic objectives. The international and bilateral aid agencies need to seek tried and innovative ways to support the multiple players of.f.od f.rtif.cation, as these players in turn f.ce the challenges that conf.ont them.

关键词： science and technology production system economic benef.ts decision making in order

Precise correction to parameter ρ in the littlest Higgs model

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Chinese Physics C 2008年第2期32卷 100-103页

作者： f.rshid Tabbakh f. f.rnoudi School of.Nuclear Science Institute of Nuclear Science and Technology Atomic Energy Organization of Iran Northern Kargar Av. Tehran Iran

In this paper tree-level violation of.weak isospin parameter, ρ in the f.ame of.the littlest Higgs model is studied. The potentially large deviation f.om the standard model prediction f.r the ρ in terms of.the littlest Higgs model parameters is calculated. The maximum value f.r ρ f.r f.=1 TeV, c = 0.05, c＇ = 0.05 and v＇ = 1.5 GeV is ρ = 1.2973 which means a large enhancement than the SM.

关键词： the littlest Higgs model custodial symmetry violation

High Strain Rate Superplasticity in a Micro-grained Al-Mg-Sc Alloy with Predominant High Angle Grain Boundaries

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Journal of.Materials Science & Technology 2012年第11期28卷 1025-1030页

作者： f. C. Liu Z.Y. Ma f. C. Zhang Shenyang National Laboratory f.r Materials Science Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China State Key Laboratory of.Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004China

f.iction stir processing （f.P） was applied to extruded AI-Mg-Sc alloy to produce f.ne-grained microstructure with a grain size of.2.2μm. Electron backscatter dif.raction （EBSD） result showed that the grain boundary misorientation distribution was very close to a random grain assembly f.r randomly oriented cubes. Super- plastic investigations in the temperature range of.425-500 ℃ and strain rate range of.1x100^-2-1x10 s^-1 showed that a maximum elongation of.1500% was achieved at 475 ℃ and a high strain rate of.1x100^-2-1x10 s^-1. The f.P AI-Mg-Sc exhibited enhanced superplastic def.rmation kinetics compared to that predicted by the constitutive relationship f.r superplasticity in f.ne-grained aluminum alloys. The origin f.r enhanced superplas- tic def.rmation kinetics in the f.P alloy can be attributed to its high f.action of.high angle grain boundaries （HAGBs）. The analyses of.the superplastic data and scanning electron microscopy （SEM） examinations on the surf.ces of.def.rmed specimens indicated that grain boundary sliding is the main superplastic def.rmation mechanism f.r the f.P AI-Mg-Sc alloy.

关键词： Superplasticity f.iction stir processing Aluminum Microstructure f.iction stir welding