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Suppression of Self-Discharge in Aqueous Supercapacitor Devices Incorporating Highly Polar Nanofiber Separators

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Energy & Environmental Materials 2023年第3期6卷 74-86页

作者： Wesley g.Buxton Simon g.King Vlad Stolojan Advanced Technology Institute University of SurreyGuildford SurreyGU27XHUK

One of the major problems limiting the applications of electric double-layer(EDLC)supercapacitor devices is their inability to maintain their cell voltage over a significant ***-discharge is a spontaneous decay in charged energy,often resulting in fully depleted devices in a matter of ***,a new method for suppressing this self-discharge phenomenon is proposed by using directionally polarized piezoelectric electrospun nanofiber films as separator *** engineering of polyvinylidene fluoride(PVDF)nanofiber films containing a small concentration of sodium dodecyl sulfate(SDS)results in a high proportion of polarβphases,reaching 380.5%of the total *** polarity into the separator material provides a reverse-diode mechanism in the device,such that it drops from an initial voltage of 1.6 down to 1 V after 10 h,as opposed to 0.3 V with a nonpolarized,commercial separator ***,the energy retained for the polarized separator is 37%and 4%for the nonpolarized separator,making supercapacitors a more attractive solution for long-term energy storage.

关键词： piezoelectric polar nanofibers PVDF separators self-discharge supercapacitors

Effects of precommercial thinning intensity on growth of Fagus orientalis Lipsky stands over 6 years

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Journal of Forestry Research 2022年第3期33卷 937-947页

作者： Deniz güney Fahrettin Atar İbrahim Turna Alkan günlü Department of Forest Engineering Faculty of ForestryKaradeniz Technical UniversityTrabzon61080Turkey Department of Forest Engineering Faculty of ForestryÇankırıKaratekin UniversityÇankırıTurkey

Determining the most suitable intensities for precommercial thinning (PCT) in oriental beech (Fagus orientalis) stands, which cover substantial areas in Turkey and have a high economic and ecological value, is essential to provide higher economic return and obtain well-formed stems. The effects of various rates of PCT interventions on the growth characteristics of natural stands, located in the northern part of Turkey, were explored to determine appropriate thinning rates;24 experimental PCT plots (4 PCT rates × 3 replications × 2 sites) were established in young thicket-stage stands and four precommercial thinning rates such as light (1 – 1.5 m spacing), moderate (1.5−2.0 m spacing) and heavy (2.5–3.0 m spacing) thinning, including a control plot (i.e., untreated), were applied. At the end of the 2007 and 2010 growing seasons, the diameter and height of the trees were measured and growth analyzed based on the 3-year and 6-year incremental growth. PCT levels were found to have significant (P ght, total basal area and total volume increment at the end of each period. The mean diameter and height increment proportionally increased with increasing PCT intensity in the third and the sixth year. In both sites, the moderate PCT provided the greatest total basal area and total volume increment. The early results indicate that the moderate PCT (1.5–2 m spacing) boosted stand development over time.

关键词： Tending operation Stand development Precommercial thinning Thicket stage

Embedded Atom Method-Based geometry Optimization Aspects of Body-Centered Cubic Metals

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Chinese Physics Letters 2013年第5期30卷 112-115页

作者： M.güler E.güler Department of Physics Hitit University19030 CorumTurkey

We present embedded atom method-based geometry optimization calculations for Fe, Cr, Mo, Nb, Ta, V and W body-centered cubic metals with Finnis–Sinclair potentials. After the optimization, we determine their typical elastic constants, bulk modulus, shear modulus, Young's modulus, Poisson's ratios, elastic wave velocities and cohesive energies. Additionally, we perform a benchmark between the experiments and the available density functional theory results. In general, our results show a good consistency with previous findings on the elastic and cohesive energy properties of the considered metals.

关键词： modulus optimization cubic

150 Years(1872-2022)of research on deep-water processes,deposits,settings,triggers,and deformation:A difficult domain of progress,dichotomy,diversion,omission,and groupthink

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Journal of Palaeogeography 2022年第4期11卷 469-564页

作者： g.Shanmugam Department of Earth and Environmental Sciences The University of Texas at ArlingtonArlingtonTX 76019USA

In capturing a snapshot of 150 years(1872-2022)of research on deep-water processes,deposits,settings,triggers,and deformation,the following 22 topics are selected:(1)*** expedition(1872-1876):The discovering of the“Challenger Deep”by the *** in the Mariana Trench has been the single most important achievement in deep-water research.(2)Five pioneers amid 50 notable contributors:***,***,***,***,and ***.(3)Mass transport:Mass-transport deposits(MTD)are the most important deep-water facies in terms of volume,geohazards,and petroleum reservoirs.(4)gravity flows:There are six basic types,namely(a)hyperpycnal flows,(b)turbidity currents,(c)debris flows,(d)liquefied/fluidized flows,(e)grain flows,and(f)thermohaline contour *** debrites are the most important petroleum reservoir *** their popularity,turbidites are not an important reservoir facies.(5)Kelvin-Helmholtz(KH)waves:Turbidites,related to KH waves,with internal hiatus are not qualified to function as predictive facies models;nor are they fit for stratigraphic correlations.(6)High-density turbidity currents(HDTC):Misclassification of density-stratified gravity flows with laminar debris flows and turbulent turbidity currents as HDTC is *** generation of density-stratified gravity flows in flume studies has debunked the concept of HDTC.(7)Classification of turbidites:Contrary to the popular groupthink,turbidites are exclusive deposits of turbidity currents.(8)Bottom currents:The four basic types of deep-marine bottom currents are:(a)thermohaline-induced geotropic contour currents,(b)wind-driven bottom currents,(c)tide-driven bottom currents(mostly in submarine canyons),and(d)internal wave/tide-driven baroclinic currents.(9)Classification of contourites:Contrary to the popular groupthink,contourites are the exclusive deposits of thermohaline-induced geotropic contour currents.(10)Tidal currents in submarine canyons:Th

关键词： Mass transport gravity flows Bottom currents High-density turbidity currents Contour currents Tidal currents Internal waves and tides Kelvin-helmholtz waves Hybrid flows The Bouma Sequence Tsunami waves Deflected sediment plumes Basin-floor fans Tutbidite groupthink Bute Inlet(BC Canada) Soft-Sediment Deformation structures(SSDS)

Breather solutions of modified Benjamin-Bona-Mahony equation

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Chinese Physics B 2021年第2期30卷 220-226页

作者： g T Adamashvili Technical University of georgia Kostava Street 77Tbilisi0179Georgia

New two-component vector breather solution of the modified Benjamin-Bona-Mahony(MBBM)equation is *** the generalized perturbation reduction method,the MBBM equation is reduced to the coupled nonlinear Schr¨odinger equations for auxiliary *** analytical expressions for the profile and parameters of the vector breather oscillating with the sum and difference of the frequencies and wavenumbers are *** two-component vector breather and single-component scalar breather of the MBBM equation is compared.

关键词： modified Benjamin-Bona-Mahony equation generalized perturbation reduction method vector breather nonlinear waves

Dinophysoid dinoflagellates from subphotic depths:Amphisolenia ***,Dinofurcula tricornuta ***.,and Dinophysis profunda ***.(Dinophysales,Dinophyceae)

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Journal of Oceanology and Limnology 2022年第2期40卷 703-711页

作者： Fernando gÓMEZ Department of Biological and Environmental Sciences and Technologies University of SalentoLecce 73100Italy

Three species of dinophysoid planktonic dinoflagellates are described from the eastern Mediterranean *** *** was collected at 70-m depth in the Ionian *** small species showed a more asymmetric midbody and a proportionally longer neck when compared to the closer relative *** individuals of Dinofurcula tricornuta *** at 154-m depth in the Marmara Sea are characterized by three posterior-oriented processes when compared to its congeneric *** is the first record of the genus Dinofurcula beyond the eastern tropical Pacific *** profunda *** at 500-m depth in the Ionian Sea is characterized by ovate hypotheca and a serrate crest-like left sulcal list when compared to its close relative *** findings evidence an undescribed biodiversity in the under-sampled subphotic depths.

关键词： deep ocean Dinophyta Dinoflagellata Mediterranean Sea mesopelagic new species

The turbidite-contourite-tidalite-baroclinite-hybridite problem: orthodoxy vs. empirical evidence behind the “Bouma Sequence”

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Journal of Palaeogeography 2021年第2期10卷 125-156页

作者： g.Shanmugam Department of Earth and Environmental Sciences The University of Texas at ArlingtonTX 76019USA

The underpinning problems of deep-water facies still remain unresolved.(1) The Tb, Tc, and Td divisions of the turbidite facies model, with traction structures, are an integral part of the "Bouma Sequence"(Ta, Tb, Tc, Td, Te).However, deposits of thermohaline contour currents, wind-driven bottom currents, deep-marine tidal currents, and baroclinic currents(internal waves and tides) also develop discrete rippled units, mimicking Tc.(2) The application of "cut-out" logic of sequences, which was originally introduced for the "Bouma Sequence", with sharp basal contacts and sandy divisions containing well-developed traction structures, to muddy contorts with gradational basal contacts and an absence of well-developed traction structures is incongruent.(3) The presence of five internal divisions and hiatus in the muddy contoured facies model is in dispute.(4) Intersection of along slope contour currents with down slope sediment-gravity flows, triggering hybrid flows, also develops traction structures.(5) The comparison of genuine hybrid flows with down slope flow transformation of gravity flows is inconsistent with etymology of the term "hybrid".(6) A reexamination of the Annot Sandstone at the Peira Cava type locality in SE France fails to validate either the orthodoxy of five internal divisions of the "Bouma Sequence" or their origin by turbidity currents. For example, the "Ta" division is composed of amalgamated units with inverse grading and floating mudstone clasts, suggesting a mass-transport deposit(MTD). The "Tb" and "Tc" divisions are composed of double mud layers and sigmoidal cross bedding, respectively, which suggest a tidalite origin.(7) Although it was reasonable to introduce a simplistic "Bouma Sequence" in 1962, at a time of limited knowledge on deep-water processes, it is obsolete now in 2021 to apply this model to the rock record amid a wealth of new knowledge.(8)The disconnect between 12 observed, but questionable, modern turbidity currents and over 10,

关键词： Turbidity currents Contour currents Tidal currents Internal waves and tides Hybrid flows The Bouma Sequence BCRS(i.e. bottom-current reworked sands)

The effectiveness of eyespots and masquerade in protecting artificial prey across ontogenetic and seasonal shifts

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Current Zoology 2022年第4期68卷 451-458页

作者： Elizabeth g Postema Department of Entomology and Nematology University of CaliforniaDavisCA 95616USA

When constraints on antipredator coloration shift over the course of development,it can be advantageous for animals to adopt different color strategies for each life *** caterpillars in the genus Papilio exhibit unique ontogenetic color sequences:for example,early instars that masquerade as bird feces,with later instars possessing eyespots.I hypothesize that larvae abandon feces masquerade in favor of eyespots due to ontogenetic changes in signaler *** ontogenetic pattern also occurs within broader seasonal shifts in background color and predator activity.I conducted predation experiments with artificial prey to determine how potential signaling constraints(specifically size and season)shape predation risk,and consequently the expression of ontogenetic color change in Papilio ***,both predation and background greenness declined significantly from July to September,though there was little evidence that these patterns impacted the effectiveness of either color *** size and color strongly affected the attack rate of avian predators:attacks increased with prey size regardless of color,and eyespotted prey were attacked more than masquerading prey *** results may reflect a key size-mediated tradeoff between conspicuousness and intimidation in eyespotted prey,and raise questions about how interwoven aspects of behavior and signal environment might maintain the prevalence of large,eyespotted larvae in nature.

关键词： ontogenetic color change eyespots masquerade predator-prey dynamics season

Luminescence enhancement of rare earth ions by metal nanostructures

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Journal of Rare Earths 2009年第4期27卷 641-645页

作者： g.A.Denisenko A.V.Shubnikov Institute of Crystallography Russian Academy of Sciences D.V.Skobeltsyn Institute of Nuclear Physics of Moscow State University

Well-ordered metal structures, i.e. arrays of nanosized tips on silver surface for studies of the luminescence enhancement of absorbed media with rare earth ions were used. These arrays were prepared by the metal evaporation on track membranes. Calculations of reso- nanee frequencies of tips regarded as semispheroids were done taking into account the interaction between dipoles of tips. They were used to discuss experimental results for media with Eu（NO3）3·6H2O salt basing on data for bulk silver dielectric function.

关键词： rare earth ions silver nanosized tips luminescence enhancement