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A New Method for Determining Fluid Compositions in the H_2O-NaClCaCl_2 System with Cryogenic Raman Spectroscopy

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Acta Geologica Sinica(English Edition) 2014年第4期88卷 1169-1182页

作者： CHI Guoxiang CHU Haixia ryan SCOTT CHOU I-Ming Department of Geology University of Regina Laboratory for Experimental Study Under Deep-sea Extreme Conditions Sanya Institute of Deep-sea Science and EngineeringChinese Academy of Sciences

Raman peaks of various hydrates in the H20-NaCl-CaCl2 system have been previously identified, but a quantitative relationship between the Raman peaks and XNaCl （i.e.,NaCl/ （NaCl＋CaCl2）） has not been established, mainly due to the difficulty to freeze the solutions. This problem was solved by adding alumina powder to the solutions to facilitate nucleation of crystals. Cryogenic （-185℃） Raman spectroscopic studies of alumina-spiced solutions indicate that XNaCl is linearly correlated with the total peak area fraction of hydrohalite. Capsules of solutions made from silica capillary were prepared to simulate fluid inclusions. Most of these artificial fluid inclusions could not be totally frozen even at temperatures as low as -185℃, and the total peak area fraction of hydrohalite is not correlated linearly with XNaCI. However, the degree of deviation （△XNaCl） from the linear correlation established earlier is related to the amount of residual solution, which is reflected by the ratio （r） of the baseline ＂bump＂ area, resulting from the interstitial unfrozen brine near 3435 cm^-1, and the total hydrate peak area between 3350 and 3600 cm^-1. A linear correlation between △XNaCl and r is established to estimate XNaCl from cryogenic Raman spectroscopic analysis for fluid inclusions.

关键词： cryogenic Raman H20-NaCl-CaCl2 XNaCI fluid inclusion

In-situ probing of thermal desorption of vapor molecules on a nanowire via work function variance

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Nano Research 2016年第11期9卷 3334-3345页

作者： Kovur Prashanthi John Eric Hawk ryan McGee Ravi Gaikwad Thomas Thundat Ingenuity Lab Department of Chemical and Materials Engineering University of Alberta Edmonton AB T6G 2V4 Canada

Nanowire sensors based on variations of their electrical properties show great potential for real-time, in situ monitoring of molecular adsorption and desorption. Although the molecular adsorption-induced change in the electronic work function is very sensitive, it does not have any specificity. However, the temperature dependency of the adsorption-induced work function variation can provide limited selectivity based on the desorption temperature. In this study, we report the in situ probing of molecular desorption by monitoring the work function variations of a single Pt nanowire as a function of temperature. The work function of a clean Pt nanowire shows a significant variation due to vapor adsorption at room temperature. Increasing the temperature of the nanowire results in a variation of the work function due to molecular desorption. Experimentally measured differential work function as a function of temperature shows desorption peaks at 36 and 44 ℃ for methanol and ethanol molecules respectively. Adsorption-induced variation of the Pt nanowire work function was further confirmed using ultraviolet photoelectron spectroscopy before and after exposure to methanol vapor. These results show that the molecular adsorption/desorption-induced variation of the work function and its temperature dependency can be used for developing nanoscale electro-calorimetric sensors.

关键词： Kelvin probe microscopy nanowires thermal desorption work function

Molecular regulation of sucrose catabolism and sugar transport for development~ defence and phloem function

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Journal of Integrative Plant Biology 2017年第5期59卷 322-335页

作者： Jun Li Limin Wu ryan Foster Yong-Ling Ruan Australia-China Research Centre for Crop Improvement and School of Environmental and Life Sciences The University of NewcastleNSW 2308 Australia CSIRO Agriculture Canberra ACT 26oi Australia

Sucrose （Suc） is the major end product of photosynthesis in mesophyll cells of most vascular plants. It is loaded into phloem of mature leaves for long-distance translocation to non-photosynthetic organs where it is unloaded for diverse uses. Clearly, Suc transport and metabolism is central to plant growth and development and the functionality of the entire vascular system. Despite vast information in the literature about the physiological roles of individual sugar metabolic enzymes and transporters, there is a lack of systematic evaluation about their molecular regulation from transcriptional to post-translational levels. Knowledge on this topic is essential for understanding and improving plant development, optimizing resource distri- bution and increasing crop productivity. We therefore focused our analyses on molecular control of key players in Suc metabolism and transport, including：（i） the identifica- tion of promoter elements responsive to sugars and hormones or targeted by transcription factors and micro- RNAs degrading transcripts of target genes; and （ii） modulation of enzyme and transporter activities through protein-protein interactions and other post-translational modifications. We have highlighted major remaining questions and discussed opportunities to exploit current understanding to gain new insights into molecular control of carbon partitioning for improving plant performance.

关键词： William J. Lucas University of California Davis USA

The impact of attractants on pocket gopher trapping

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Current Zoology 2014年第4期60卷 472-478页

作者： Roger A. BALDWIN ryan MEINERZ Steve B. ORLOFF Department of Wildlife Fish and Conservation Biology University of California-Davis Davis CA 95616 USA University of California Cooperative Extension 1655 South Main Street Yreka CA 96097 USA

Pocket gophers （Geomyidae） have an extensive impact on both natural and agricultural systems. Trapping is a tech- nique often used to sample and manage these populations. The identification of an attractant that increases capture rates of pocket gophers would greatly assist researchers and pest management professionals alike. Therefore, we tested the attractiveness of four attractants （peanut butter, anise, grapefruit attractant, and carrot） plus a control （no attractant） using uncovered and covered trap sets to determine what impact they have on visitation and capture rates of pocket gophers. We also determined how the impact of cover status and attractants differ across varying weights and gender of pocket gophers. We found no direct effect of any attracrant on visitation and capture rates of pocket gophers, nor on the gender of captured individuals. However, when no attractant was used, the mtmber of pocket gophers captured per 100 trap nights was greater when trap sets were uncovered vs. when covered, and capture rates were generally high and consistent when using peanut butter as an attractant. Additionally, we noted that covered trap sets that were baited with peanut butter yielded heavier pocket gopher captures than uncovered trap sets using this same attractant. This is key, given the difficulty associated with capturing older, more experienced individuals. Combined with data from a previous investigation, this suggests that there is no advantage to using any attractant when utilizing uncovered trap sets, but there is likely some benefit to using peanut butter in covered trap sets [Current Zoology 60 （4）： 472-478, 2014].

关键词： Attractant Demographics Pocket gopher Thomomys bottae Thomomys talpoides Trapping

Female mate choice and the potential for ornament evolution in túngara frogs Physalaemus pustulosus

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Current Zoology 2010年第3期56卷 343-357页

作者： Michael J.ryan Ximena E.BERNAL A.Stanley RAND Section of Integrative Biology C0930 University of Texas Smithsonian Tropical Research Institution Department of Biological Science Texas Tech University Srnithsonian Tropical Research Institution

The potential for ornament evolution in response to sexual selection rests on the interaction between the permissive- ness or selectivity of female preferences and the constraints on male development of signaling related traits. We investigate the former by determining how latent female preferences either exaggerate the magnitude of current traits （i.e. elaborations） or favor novel traits （i.e. innovations）. In tt^ngara frogs, females prefer complex mating calls （whine-chucks） to simple calls （whine only）. The whine is critical for mate recognition while the chuck further enhances the attractiveness of the call. Here we use a combina- tion of synthetic and natural stimuli to examine latent female preferences. Our results show that a diversity of stimuli, including conspecific and heterospecific calls as well as predator-produced and human-made sounds, increase the attractiveness of a call when added to a whine. These stimuli do not make simple calls more attractive than a whine-chuck, however. In rare cases we found stimuli that added to the whine decrease the attractiveness of the call. Overall, females show strong preferences for both elaborations and innovations of the chuck. We argue that the emancipation of these acoustic adornments from mate recognition allows such female permissiveness, and that male constraints on signal evolution are probably more important in explaining why males evolved their specific adornment. Experimentally probing latent female preferences for stimuli out of the species＇ range is a useful means to gain insights about the potential of female choice to influence signal evolution and thus the astounding diversity in male sexually-selected traits [Current Zoology 56 （3）： 343-357, 2010].

关键词： Mate choice Ornament evolution Tfingara frogs Physalaemus pustulosus

Demonstration of tantalum as a structural material for MEMS thermal actuators

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Microsystems & Nanoengineering 2021年第1期7卷 85-97页

作者： Longchang Ni ryan M.Pocratsky Maarten P.de Boer CMU Mechanical Engineering Dept. 5000 Forbes Ave.PittsburghPA 15213USA Present address:Fischione Instruments 9003 Corporate CirExportPA 15632USA

This work demonstrates the processing,modeling,and characterization of nanocrystalline refractory metal tantalum(Ta)as a new structural material for microelectromechanical system(MEMS)thermal actuators(TAs).Nanocrystalline Ta films have a coefficient of thermal expansion(CTE)and Young’s modulus comparable to bulk Ta but an approximately ten times greater yield *** mechanical properties and grain size remain stable after annealing at temperatures as high as 1000°*** has a high melting temperature(Tm=3017℃)and a low resistivity(ρ=20µΩcm).Compared to TAs made from the dominant MEMS material,polycrystalline silicon(polysilicon,Tm=1414℃,ρ=2000µΩcm),Ta TAs theoretically require less than half the power input for the same force and displacement,and their temperature change is half that of *** TAs operate at a voltage 16 times lower than that of other TAs,making them compatible with complementary metal oxide semiconductors(CMOS).We selectα-phase Ta and etch 2.5-μm-thick sputterdeposited films with a 1μm width while maintaining a vertical sidewall profile to ensure in-plane movement of TA *** is 25 times thicker than the thickest reactive-ion-etchedα-Ta reported in the technical *** stress sensitivities to sputter parameters and to hydrogen incorporation are investigated and ***,a V-shaped TA is fabricated and tested in *** conventional actuation by Joule heating and passive self-actuation are as predicted by models.

关键词： thermal structural thick

Superconvergence and the Numerical Flux: a Study Using the Upwind-Biased Flux in Discontinuous Galerkin Methods

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Communications on Applied Mathematics and Computation 2020年第3期2卷 461-486页

作者： Daniel J.Frean Jennifer K.ryan School of Mathematics University of East AngliaNorwichUK Applied Mathematics and Statistics Colorado School of MinesGoldenCOUSA

One of the beneficial properties of the discontinuous Galerkin method is the accurate wave propagation *** is,the semi-discrete error has dissipation errors of order 2k+1(≤Ch2k+1)and order 2k+2 for dispersion(≤Ch2k+2).Previous studies have concentrated on the order of accuracy,and neglected the important role that the error constant,C,plays in these *** this article,we show the important role of the error constant in the dispersion and dissipation error for discontinuous Galerkin approximation of polynomial degree k,where k=0,1,2,*** gives insight into why one may want a more centred flux for a piecewise constant or quadratic approximation than for a piecewise linear or cubic *** provide an explicit formula for these error *** is illustrated through one particular flux,the upwind-biased flux introduced by Meng et al.,as it is a convex combination of the upwind and downwind *** studies of wave propagation are typically done through a Fourier *** higher order Fourier information can be extracted using the smoothness-increasing accuracy-conserving(SIAC)*** SIAC filter ties the higher order Fourier information to the negative-order norm in physical *** show that both the proofs of the ability of the SIAC filter to extract extra accuracy and numerical results are unaffected by the choice of flux.

关键词： Discontinuous Galerkin Smoothness-increasing accuracy-conserving(SIAC)filtering Superconvergence

FAIR Data and Metadata:GNSS Precise Positioning User Perspective

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Data Intelligence 2023年第1期5卷 43-74页

作者： Ivana Ivánová ryan Keenan Christopher Marshall Lori Mancell Eldar Rubinov ryan Ruddick Nicholas Brown Graeme Kernich Spatial Sciences School of Earth and Planetary ScienceCurtin UniversityPerthWestern Australia6102Australia Positioning Insights Carlton NorthVictoria3054Australia FrontierSI Cnr Village St and Fishplate LnDocklandsVictoria3008Australia Geoscience Australia Cnr Jerrabomberra Ave and Hindmarsh DriveSymonstonAustralian Capital Territory2609Australia

The FAIR principles of Wilkinson et al.[1]are finding their way from research into application domains,one of which is the precise positioning with global satellite navigation systems(GNSS).Current GNSS users demand that data and services are findable online,accessible via open protocols(by both,machines and humans),interoperable with their legacy systems and reusable in various *** metadata are essential in seamless communication between GNSS data and service providers and their users,and,for decades,geodetic and geospatial standards are efficiently implemented to support ***,GNSS user community is transforming from precise positioning by highly specialised use by geodetic professionals to every-day precise positioning by autonomous vehicles or wellness obsessed ***,rapid technological developments allow alternative ways of offering data and services to their *** transforming circumstances warrant a review whether metadata defined in generic geospatial and geodetic standards in use still support FAIR use of modern GNSS data and services across its novel user *** paper reports the results of current GNSS users'requirements in various application sectors on the way data,metadata and services are *** engaged with GNSS stakeholders to validate our findings and to gain understanding on their perception of the FAIR *** results confirm that offering FAIR GNSS data and services is fundamental,but for a confident use of these,there is a need to review the way metadata are offered to the *** standard compliant GNSS community metadata profile and providing relevant metadata with data on-demand,the approach outlined in this paper,is a way to manage current GNSS users'expectations and the way to improve FAIR GNSS data and service delivery for both humans and the machines.

关键词： FAIR Metadata Standards Profile Precise positioning GNSS users Spatial data infrastructure

A person-centered approach to achievement goal orientations in competitive tennis players: Associations with motivation and mental toughness

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Journal of Sport and Health Science 2021年第1期10卷 73-81页

作者： Richard Gregory Cowden Nicolas Mascret Timothy ryan Duckett Department of Behavioural Medicine University of KwaZulu-NatalDurbanKwaZulu-Natal 4041South Africa Department of Psychology Middle Tennessee State UniversityMurfreesboroTN 37132USA Aix Marseille Univ CNRSISMMarseille 13007France Department of Educational Foundations and Leadership University of ToledoToledoOH 43610USA

Background:Research on achievement goal orientations in sport has typically relied on the use of variable-centered approaches that tend to overlook population *** this study,we used a person-centered approach to identify subgroups of competitive tennis players according to unique combinations of achievement goal orientations and tested for subgroup differences in motivation and mental ***:A sample of 323 competitive tennis athletes(69.35%male)between 15 and 25 years of age(17.60±2.40 years,mean±SD)completed the 3×2 Achievement Goal Questionnaire for Sport,Sport Motivation Scale Ⅱ,and Mental Toughness *** profile analysis was used to identify unique combinations of achievement goal *** between latent subgroups on autonomous motivation,controlled motivation,and mental toughness were performed using analysis of ***:Latent profile analysis supported 3 distinct patterns of achievement goal profiles that were primarily distinguishable based on valence of competence(i.e.,approach ***).Analyses of variance indicated that athletes who were classified into subgroups that endorsed approach types of goals(regardless of the types of avoidance goals they endorsed)reported higher levels of autonomous motivation and mental ***:Results indicated that athletes tend to pursue a number of achievement goals collectively rather than in *** approach goals are more commonly linked to adaptive psychological functioning and positive outcomes,avoidance goals may also be associated with desirable psychological characteristics if they are pursued in conjunction with approach types of achievement goals.

关键词： Achievement goals Latent profile analysis Mental toughness Motivation Sport