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Journal of Environmental Sciences 2024年第1期135卷 669-680页

作者： Meichen Wang Kelly J Rivenbark timothy d phillips Veterinary Physiology and Pharmacology College of Veterinary Medicine and Biomedical SciencesTexas A&M UniversityTX 77845USA

The co-occurrence of glyphosate(GLP)and aminomethylphosphonic acid(AMPA)in contaminated water,soil,sediment and plants is a cause for concern due to potential threats to the ecosystem and human health.A major route of exposure is through contact with contaminated soil and consumption of crops containing GLP and AMPA ***,clay-based sorption strategies for mixtures of GLP and AMPA in soil,plants and garden produce have been very *** this study,in vitro soil and in vivo genetically modified corn models were used to establish the proof of concept that the inclusion of clay sorbents in contaminated soils will reduce the bioavailability of GLP and AMPA in soils and their adverse effects on plant *** of chemical concentration(1–10 mg/kg),sorbent dose(0.5%-3%in soil and 0.5%-1%in plants)and duration(up to 28 days)on sorption kinetics were *** time course results showed a continuous GLP degradation to *** inclusion of calcium montmorillonite(CM)and acid processed montmorillonite(APM)clays at all doses significantly and consistently reduced the bioavailability of both chemicals from soils to plant roots and leaves in a dose-and time-dependent manner without detectable *** treated with 0.5%and 1%APM inclusion showed the highest growth rate(p≤0.05)and lowest chemical bioavailability with up to 76%reduction in roots and57%reduction in *** indicated that montmorillonite clays could be added as soil supplements to reduce hazardous mixtures of GLP and AMPA in soils and plants.

关键词： Glyphosate AMPA Adsorption Soil remediation Plant Hydroponic system

decreased bioavailability of aminomethylphosphonic acid(AMPA)in genetically modified corn with activated carbon or calcium montmorillonite clay inclusion in soil

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Journal of Environmental Sciences 2021年第2期33卷 131-143页

作者： Sara E.Hearon Meichen Wang Thomas J.Mcdonald timothy d.phillips Veterinary Integrative Biosciences department College of Veterinary Medicine and Biomedical Sciences Texas A&M Uniuersity College StationTx 77845USA department of Environmental and Occupational Health School of Public Health Texas A&M UniversityCollege Station400 Bizzell St College StationTX 77843USA

The widespread use of pesticides has resulted in detectable residues throughout the environment,sometimes at concentrations well above regulatory ***,the development of safe,effective,field-practical,and economically feasible strategies to mitigate the effects of pesticides is *** is an organophosphorus herbicide that is degraded to aminomethylphosphonic acid(AMPA),a toxic and persistent metabolite that can accumulate in soil and sediment and translocate to *** this study,we investigated the binding efficacy of activated carbon(AC)and calcium montmorillonite(CM)clay to decrease AMPA bioavailability from soil and AMPA translocation to *** isotherms and thermodynamic studies on AC and CM were conducted and showed tight binding(enthalpy values>-20 k J/mol)for AMPA with high capacities(0.25 mol/kg and 0.38 mol/kg,respectively),based on derivations from the Langmuir model.A hydra assay was utilized to indicate toxicity of AMPA and the inclusion of 1%AC and CM both resulted in 90%protection of the hydra(**p≤0.01).Further studies in glyphosate-contaminated soil showed that AC and CM significantly reduced AMPA bioavailability by 53%and 44%,*** in genetically modified(GM)corn showed a conversion of glyphosate to AMPA in roots and sprouts over a 10-day exposure *** of AC and CM reduced AMPA residues in roots and sprouts by 47%-61%.These studies collectively indicate that AC and CM are effective sorbents for AMPA and could be used to reduce AMPA bioavailability from soil and AMPA residues in GM corn plants.

关键词： Glyphosate AMPA Activated carbon Calcium montmorillonite Sorbent

Relative Competitiveness of Nimblewill (Muhlenbergia schreberi) with Tall Fescues and Kentucky Bluegrass

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American Journal of Plant Sciences 2014年第26期5卷 3777-3787页

作者： Pedro V. d. Moraes Willian W. Witt timothy d. phillips Patricia Rossi Luis E. Panozzo Federal Technologic University of Paraná UTFPR Dois Vizinhos Brazil University of Kentucky Lexington USA Federal University of Pelotas Pelotas Brazil

Nimblewill (Muhlenbergia schreberi) is a warm-season perennial grass (weed) native to the United States and Canada with low palatability. This species is dominant in many horse pastures in which bluegrass (Poa pratensis) is the primary forage. Tall fescues infected with endophyte fungae gives tall fescue plants greater competitividade ability and enviromental stress tolerance than their noninfected counterparts. The purpose of this study was to compare the relative competitiveness of nimblewill with bluegrass and tall fescues (Lolium arundinaceum) with or without endophytic fungi (strain AR584) through experiments using a replacement series design. Replacement series experiments were conducted in pots to evaluate the growth of species in a pure stand and in a mix stand with variables rates. Species competitiveness was evaluated based on the relative yield and relative yield total (and competitiveness index) of the dry weight of shoots from species grown together. Nimblewill was found to be more competitive than bluegrass, and all tall fescues were more competitive than nimblewill. Our results demonstrated that the presence of endophytes in three different tall fescues did not alter the competitiveness of these fescues with nimblewill, but the tall fescue Kentucky 31 was more competitive between tall fescues. Based on our finding, we concluded that fescues are recommended, especially without the endophytic fungi to suppress nimblewill in implantation of pastures to horses.

关键词： Competition Pastures Weed Endophytic Fungi

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饲料中霉菌毒素的控制

饲料广角 2001年第21期 50-52页

作者：孙安权 H.C. Ng timothy d.phillips 奥格营养有限公司

世界上每年大约有25%的谷物遭受各种霉菌污染,因污染程度不同,造成不同地区损失差异较大.西方国家多对饲料中的黄曲霉毒素有规定,且丹麦不仅限制饲料中而且也检查肉品中的黄曲霉毒素.

关键词：饲料霉菌毒素霉菌脱霉素控制吸附剂

The formation of orthogonal joint systems and cuboidal blocks:New insights gained from flat-lying limestone beds in the region of Havre-Saint-Pierre(Quebec,Canada)

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第12期15卷 3079-3093页

作者： Shaocheng Ji Yvéric Rousseau denis Marcotte Noah John phillips département des Génies Civil Géologique et des MinesÉcole Polytechnique de MontréalMontréalQuébecH3C 3A7Canada department of Geology Lakehead UniversityThunder BayOntarioP7B 5E1Canada

Vertical orthogonal joints are a common feature in shallow crustal *** are several competing theories for their formation despite the *** examined the exceptional exposures of orthogonal joints in flat-lying Ordovician limestone beds from the Havre-Saint-Pierre Region in Quebec,Canada(north shore of Saint-Lawrence River)to test conceptual models of joint formation in a natural *** the region,the spacing of cross-joints is consistently larger than the spacing of systematic joints by a factor of 1.5 *** joint-spacing-to-bed-thickness ratios(s/t)are much larger in these beds(s/t=4.3 for systematic joints,and 6.4 for cross-joints)than those in higher strained strata along the south shore of the Saint-Lawrence River(s/t=1),highlighting the effect of tectonic strain in decreasing fracture spacing and block *** high values of s/t indicate that cross-joint formation was unlikely caused by a switch from compression to tension once a critical s/t ratio for systematic joints was reached(as hypothesized in previous studies).We proposed a new model for the formation of orthogonal joint systems where the principal stress axes locally switch during the formation of systematic *** presence of ladder-shaped orthogonal joints suggests a state of effective stress withσ_(1)^(∗)≫0>σ_(2)^(∗)>σ_(3)^(∗)and whereσ_(2)^(∗)-σ_(3)^(∗)is within the range of fracture strength variability at the time of *** research provides a new mechanical model for the formation of orthogonal joint systems and cuboidal blocks.

关键词： Plato's cuboids Orthogonal joints Fracture spacing Limestone Layered rock mechanics Appalachian geology

Transradial versus transfemoral access for anterior circulation mechanical thrombectomy: analysis of 375 consecutive cases

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Stroke & Vascular Neurology 2021年第2期6卷 207-213页

作者： timothy John phillips Matthew Thomas Crockett Gregory d Selkirk Ruchi Kabra Albert Ho Yuen Chiu Tejinder Singh Constantine Phatouros William McAuliffe Neurological Intervention and Imaging Service of Western Australia Sir Charles Gairdner HospitalPerthWestern AustraliaAustralia Neurological Intervention and Imaging Service of Western Australia Fiona Stanley HospitalPerthWestern AustraliaAustralia Neurological Intervention and Imaging Service of Western Australia Royal Perth HospitalPerthWestern AustraliaAustralia

Objective To compare transradial artery access(TRA)to the gold standard of transfemoral artery access(TFA)in mechanical thrombectomy(MT)for stroke caused by anterior circulation large vessel *** The clinical outcomes,procedural speed,angiographic efficacy and safety of both techniques were analysed in 375 consecutive cases over an 18-month period in a high volume statewide neurointerventional *** There was no significant difference in patient characteristics,stroke parameters,imaging techniques or intracranial *** median time elapsed between CT scanning and reperfusion was 96.5 min(IQR 68-123)in the TFA group and 95 min(IQR 68-123)in the TRA group(p=0.456).Of 336 patients who were independent at presentation 58%(124/214)of the TFA group and 67%(82/122)of the TRA group had a modified Rankin score of 0-2 at 90-day follow-up(p=0.093).Cross-over from radial to femoral was 4.6%(4/130)compared with 1.6%cross-over from femoral to radial(4/245),but did not meet the predetermined level of statistical significance(OR2.92,95% CI 0.81 to 10.52,p=0.088) and did not impact median procedural *** angiographic reperfusion,first pass reperfusion,embolisation to new territory and symptomatic intracranial haemorrhage were similar in both *** was a significant difference in major access site complications requiring an additional *** of the TRA cases had a major access site complication but 6.5%(16/245)of the TFA cases did(p=0.003).Conclusion This study suggests that using TRA for anterior circulation MT is fast,efficacious,safe and not inferior to the gold standard of TFA.

关键词： service radial cases

Amplitude-mode spectroscopy of chemically injected and photogenerated charge carriers in semiconducting single-walled carbon nanotubes

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Nano Research 2023年第4期16卷 5619-5625页

作者： Shai R。Vardeny Alan phillips Kira A。Thurman ZValy Vardeny Jeffrey L.Blackburn division of Electrical Electronicand Infocommunications EngineeringOsaka University2-1 Yamada-okaSuitaOsaka 565-0871Japan Materials Chemistryand Computation Science DirectorateNational Renewable Energy LaboratoryGoldenCO 80401USA department of Physics Colorado School of MinesGoldenCO 80401USA department of Physics&Astronomy University of UtahSalt Lake CityUT 84112USA

In one-dimensional semiconductors such as conjugated polymers and semiconducting single-walled carbon nanotubes(s-SWCNTs),injected charge carriers(electrons or holes)can have profound impacts on both electronic conductivity and optical spectra,even at low carrier *** charge-related spectral features is a key fundamental challenge with important technological ***,we employ a systematic suite of experimental and theoretical tools to understand the mid-infrared charge signatures of heavily p-type doped polymer-wrapped *** a broad range of nanotube diameters,we find that hole charge carriers induce strong Fano anti-resonances in mid-infrared transmission spectra that correspond to defect-related(d-band)and in-plane tangential(G-band)Raman-active vibrational modes,along with antiresonances arising from infrared(IR)-active polymer and SWCNT *** employ^(13)C isotope-labeled s-SWCNTs and a removable wrapping polymer to clarify the relative intensities,energies,and sources of all observed *** performed with the“amplitude mode model”are used to quantitatively reproduce Raman spectra and also help to explain the outsized intensity of the d-band anti-resonance,relative to the G-band,observed for both moderately and degenerately doped *** results provide a framework for future studies of ground-and excited-state charge carriers in s-SWCNTs and a variety of low-dimensional materials.

关键词： carbon nanotubes doping charge carriers phonons electron-phonon coupling

Fano Factor in Strained Graphene Nanoribbon Nanodevices

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Chinese Physics Letters 2017年第11期34卷 114-118页

作者： Walid Soliman Mina d.Asham Adel H.phillips Faculty of Engineering Benha UniversityBenhaEgypt Faculty of Engineering AinShams UniversityCairoEgypt

We investigate the Fano factor in a strained armchair and zigzag graphene nanoribbon nanodevice under the effect of ac field in a wide range of frequencies at different temperatures （10？K–70？K）. This nanodevice is modeled as follows： a graphene nanoribbon is connected to two metallic leads. These two metallic leads operate as a source and a drain. The conducting substance is the gate electrode in this three-terminal nanodevice. Another metallic gate is used to govern the electrostatics and the switching of the graphene nanoribbon channel. The substances at the graphene nanoribbon/metal contact are controlled by the back gate. The photon-assisted tunneling probability is deduced by solving the dirac eigenvalue differential equation in which the Fano factor is expressed in terms of this tunneling probability. The results show that for the investigated nanodevice, the Fano factor decreases as the frequency of the induced ac field increases, while it increases as the temperature increases. In general, the Fano factors for both strained armchair and zigzag graphene nanoribbons are different. This is due to the effect of the uniaxial strain. It is shown that the band structure parameters of graphene nanoribbons at the energy gap, the C–C bond length, the hopping integral, the Fermi energy and the width are modulated by uniaxial strain. This research gives us a promise of the present nanodevice being used for digital nanoelectronics and sensors.

关键词： Fano Factor in Strained Graphene Nanoribbon Nanodevices

Photo-Induced Spin dynamics in Nanoelectronic devices

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Chinese Physics Letters 2012年第10期29卷 248-252页

作者： Mina d.Asham Walid A.Zein Adel H.phillips Faculty of Engineering Benha UniversityBenhaEgypt Faculty of Engineering Ain-Shams UniversityCairoEgypt

The present research is devoted to the investigation of electron spin transmission through a nanoelectronic *** device is modeled as nonmagnetic semiconductor quantum dot coupled to two diluted magnetic semiconductor *** spin transport characteristics through such a device are investigated under the effect of an ac-field of a wide range of *** present result shows a periodic oscillation of the conductance for both the cases of parallel and antiparallel spin *** oscillations are due to *** for spin polarization and giant magneto-resistance show the coherency *** present research might be useful for developing single spin-based quantum bits(qubits)required for quantum information processing and quantum spin-telecommunication.

关键词： property quantum electronic

Thin liquid film morphology driven by electro-static field

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Applied Mathematics and Mechanics(English Edition) 2011年第8期32卷 1039-1046页

作者： E.M.TIAN T.P.SVOBOdNY J.d.phillips department of Mathematics and Statistics Wright State University

The development of stationary patterns on a thin polymer surface subject to an electric field is studied by means of the hexagonal-planform weakly nonlinear stability analysis and numerical simulations. The time evolution of the interface between the air and the polymer film on the unbounded spatial domain is described by a thin film equation, incorporating the electric driving force and the surface *** nonlinear interfacial growth includes the amplitude equations and superposition of one-dimensional structures at regular orientations. The pattern selection is driven by the subcritical instability mechanism in which the relative thickness of the polymer film plays a critical role.

关键词： thin film pattern formation electrohydrodynamic instability