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surface storm flow prediction on hillslopes based on topography and hydrologic connectivity

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Ecological Processes 2016年第1期5卷 153-165页

作者： dennis W.Hallema Roger Moussa Ge sun steven G.McNulty INRA UMR LISAH Laboratoire d’etude des Interactions Sol-Agrosysteme-Hydrosysteme(INRAIRDMontpellier SupAgro)2 place Pierre Viala34060 Montpellier CEDEX 2France U.s.Department of Agriculture Forest service Eastern Forest Environmental Threat Assessment CenterSouthern Research StationRaleighNC 27606USA U.s.Department of Energy Oak Ridge Institute for Science and EducationOak RidgeTN 37830USA

Background:Hillslopes provide critical watershed ecosystem services such as soil erosion control and storm flow regulation through collecting,storing,and releasing rain *** intense rainstorms,rainfall intensity and infiltration capacity on the hillslope control Hortonian runoff while the topographic attributes of the hillslope(e.g.,slope,aspect,curvature)and the channel network define the structural hydraulic connectivity that determines how rapidly excess water is *** paper discusses literature on the link between topographic attributes and hydrologic connectivity and demonstrates how this link can be used to define a parsimonious model for predicting surface runoff during high intensity *** text:First,we provide a topographic characterization of the hillslope necessary to determine the structural hydrologic connectivity of surface flow based on existing ***,we demonstrate a hydrologic surface response model that routes the geomorphologic unit hydrograph(GIUH)through a spatial domain of representative elementary hillslopes reflecting the structural hydrologic *** attributes impact flow and travel time distributions by affecting gravitational acceleration of overland flow and channel,solar irradiance,flow deceleration by vegetation,and flow divergence/***:We show with an example where we apply the GIUH-based model to hypothetical hillslopes that the spatial organization of the channel network is critical in the flow and travel time distribution,and that topographic attributes are key in obtaining simple yet accurate representations of hydrologic *** GIUH models of surface runoff that use this hydrologic connectivity have the advantage of low data requirements,being scalable and applicable regardless of the spatial complexity of the hillslope,and have the potential to fundamentally improve flood forecasting tools used in the assessment of ecosystem servi

关键词： Hydrological processes Hydrologic connectivity storm flow Ecosystem services GIUH

The development of *** erosion prediction and modeling

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International soil and Water Conservation Research 2013年第2期1卷 1-11页

作者： John M.Laflen dennis C.Flanagan lowa state U. UsDA-ARs National soil Erosion Research Laboratory West LafayetteIN

soil erosion prediction technology began over 70 years ago when Austin Zingg published a relationship between soil erosion(by water)and land slope and length,followed shortly by a relationship by Dwight smith that expanded this equation to include conservation ***,it was nearly 20 years before this work's expansion resulted in the Universal soil Loss Equation(UsLE),perhaps the foremost achievement in soil erosion prediction in the last *** UsLE has increased in application and complexity,and its usefulness and limitations have led to the development of additional technologies and new science in soil erosion research and *** among these new technologies is the Water Erosion Prediction Project(WEPP)model,which has helped to overcome many of the shortcomings of the UsLE,and increased the scale over which erosion by water can be *** of application of erosion prediction include almost all land types:urban,rural,cropland,forests,rangeland,and construction *** applications of WEPP include prediction of radioactive material movement with soils at a superfund cleanup site,and near real-time daily estimation of soil erosion for the entire state of Iowa.

关键词： Universal soil Loss Equation Water Erosion Prediction Project soil erosion Erosion prediction History of erosion prediction

Role of dopamine in the pathophysiology of Parkinson’s disease

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Translational Neurodegeneration 2023年第1期12卷 281-295页

作者： Zhi Dong Zhou Ling Xiao Yi dennis Qing Wang Tit Meng Lim Eng King Tan National Neuroscience Institute of singapore 11 Jalan Tan Tock SengSingapore 308433Singapore Department of Neurology Singapore General HospitalOutram RoadSingapore 169608Singapore signature Research Program in Neuroscience and Behavioral Disorders Duke-NUS Graduate Medical School Singapore8 College RoadSingapore 169857Singapore Department of Neurology Zhujiang HospitalSouthern Medical UniversityGuangzhou 510280China Department of Biological science National University of SingaporeSingapore 119077Singapore

A pathological feature of Parkinson’s disease(PD)is the progressive loss of dopaminergic neurons and decreased dopamine(DA)content in the substantia nigra pars compacta in PD *** is the neurotransmitter of dopaminergic *** evidence suggests that DA interacts with environmental and genetic factors to contribute to PD *** of DA synthesis,storage,transportation and metabolism have been shown to promote neurodegeneration of dopaminergic neurons in various PD *** is unstable and can undergo oxidation and metabolism to produce multiple reactive and toxic by-products,including reactive oxygen species,DA quinones,and 3,*** we summarize and highlight recent discoveries on DA-linked pathophysiologic pathways,and discuss the potential protective and therapeutic strategies to mitigate the complications associated with DA.

关键词： Dopamine Dopamine quinones 3,4-Dihydroxyphenylacetaldehyde Neurodegeneration Pathogenesis Parkinson’s disease Reactive oxygen species Therapeutic strategies

Highly refractory Archaean peridotite cumulates:Petrology and geochemistry of the seqi Ultramafic Complex,sW Greenland

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Geoscience Frontiers 2018年第3期9卷 689-714页

作者： Kristoffer szilas Vincent van Hinsberg Iain McDonald Tomas Naeraa Hugh Rollinson Jacob Adetunji dennis Bird Department of Geological sciences Stanford University450 Serra MallStanfordCA 94305USA Department of Earth&Planetary sciences McGill UniversityQuebecCanada Department of Geology Lund UniversitySovegatan 12223 62 LundSweden school of Earth and Ocean sciences Cardiff UniversityMain BuildingCardiff CF10 3ATUnited Kingdom College of science University of DerbyDerbyDE22 1GBUK

This paper investigates the petrogenesis of the seqi Ultramafic Complex, which covers a total area of approximately 0.5 km^2. The ultramafic rocks are hosted by tonalitic orthogneiss of the ca. 3000 Ma Akia terrane with crosscutting granitoid sheets providing an absolute minimum age of 2978 ± 8 Ma for the seqi Ultramafic Complex. The seqi rocks represent a broad range of olivine-dominated plutonic rocks with varying modal amounts of chromite, orthopyroxene and amphibole, i.e. various types of dunite(s.s.),peridotite(s.l.), as well as chromitite. The seqi Ultramafic Complex is characterised primarily by refractory dunite, with highly forsteritic olivine with core compositions having Mg# ranging from about 91 to 93. The overall high modal contents, as well as the specific compositions, of chromite rule out that these rocks represent a fragment of Earth's mantle. The occurrence of stratiform chromitite bands in peridotite, thin chromite layers in dunite and poikilitic orthopyroxene in peridotite instead supports the interpretation that the seqi Ultramafic Complex represents the remnant of a fragmented layered complex or a magma conduit, which was subsequently broken up and entrained during the formation of the regional continental *** all of the characteristics of the seqi Ultramafic Complex points to formation of these highly refractory peridotites from an extremely magnesian(Mg# ~ 80), near-anhydrous magma, as olivinedominated cumulates with high modal contents of chromite. It is noted that the seqi cumulates were derived from a mantle source by extreme degrees of partial melting(>40%). This mantle source could potentially represent the precursor for the sub-continental lithospheric mantle(sCLM) in this region,which has previously been shown to be ultra-depleted. The seqi Ultramafic Complex, as well as similar peridotite bodies in the Fiskefjord region, may thus constitute the earliest cumulates that formed during the large-scale melting event(s), which

关键词： North Atlantic Craton Archaean Dunite Platinum-group elements Ultra-depleted mantle Fiskefjord

A Methodology for Producing Uniform Distribution of UO2 in a Tungsten Matrix

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Journal of Physical science and Application 2015年第4期5卷 255-262页

作者： dennis s. Tucker Andrew O'Connor Robert Hickman NAsA EM32 MSFC Alabama 35812 United State of America Department of Nuclear Engineering Purdue University West Lafayette Indiana 47907 United States of America

We report a method to produce a uniform mixture of uranium dioxide spherical particles in a tungsten matrix. This method involves mixing 0.5 weight percent of high density polyethylene binder with 60 volume percent uranium dioxide spheres and 40 volume percent tungsten powders. Initially, hafnium oxide spheres were used as a surrogate for uranium dioxide spheres. The HfO2/W/PE powders were thoroughly mixed in a Turbula, then mixed on a hot plate above the drop point of the binder. These powders were then densified using spark plasma sintering. Microstructure was evaluated using scanning electron microscopy, density was measured and hardness measurements were made. Initial carbon content of the powders were measured and carbon content of the sintered materials was measured. subsequently, W/UO2/Binder powders were mixed using the same methodology to ensure the process could be used for this system. These powders were sintered using hot isostatic pressing and microstructures evaluated. The resultant microstructures contained uniform distribution of HfO2 and UO2 particles in the tungsten matrix with very low carbon content.

关键词： Nuclear propulsion tungsten depleted uranium oxide hafnium oxide powder processing spark plasma sintering.

Pandemic spotlight on urban water quality

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Ecological Processes 2020年第1期9卷 249-251页

作者： dennis W.Hallema François-Nicolas Robinne steven G.McNulty Department of Forestry and Environmental Resources North Carolina State University3041 East Cornwallis RoadResearch Triangle ParkNC 27709USA Canadian Partnership for Wildland Fire science Department of Renewable ResourcesUniversity of Alberta751 General Services BuildingEdmontonAB T6G 2H1Canada Eastern Forest Environmental Threat Assessment Center Southern Research StationU.S.Department of Agriculture Forest ServiceResearch Triangle ParkNC 27709USA.

surface water improvements associated with the COVID-19 economic slowdown illustrate environmental resiliency and societal control over urban water quality.

关键词： urban quality. water

Routing with Cooperative Nodes Using Improved Learning Approaches

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Intelligent Automation & soft Computing 2023年第3期35卷 2857-2874页

作者： R.Raja N.satheesh J.Britto dennis C.Raghavendra Department of CsIT CVR College of EngineeringTelanganaIndia Department of Computer science and Engineering St.Martin’s Engineering CollegeSecunderabadTelanganaIndia Department of Computer science and Engineering Dhanalakshmi Srinivasan UniversityTrichyTamilnaduIndia CsIT Department CVR College of EngineeringHyderabadIndia

In IoT,routing among the cooperative nodes plays an incredible role in fulﬁlling the network requirements and enhancing system *** eva-luation of optimal routing and related routing parameters over the deployed net-work environment is *** research concentrates on modelling a memory-based routing model with stacked Long short Term Memory(s-LsTM)and Bi-directional Long short Term Memory(b-LsTM).It is used to hold the routing information and random routing to attain superior *** pro-posed model is trained based on the searching and detection mechanisms to com-pute the packet delivery ratio(PDR),end-to-end(E2E)delay,throughput,*** anticipated s-LsTM and b-LsTM model intends to ensure Quality of service(Qos)even in changing network *** performance of the proposed b-LsTM and s-LsTM is measured by comparing the signiﬁcance of the model with various prevailing ***,the performance is measured with Mean Absolute Error(MAE)and Root Mean square Error(RMsE)for mea-suring the error rate of the *** prediction of error rate is made with Learn-ing-based stochastic Gradient Descent(L-sGD).This gradual gradient descent intends to predict the maximal or minimal error through successive *** simulation is performed in a MATLAB 2020a environment,and the model performance is evaluated with diverse *** anticipated model intends to give superior performance in contrast to prevailing approaches.

关键词： Internet of Things(IoT) stacked long short term memory bi-directional long short term memory error rate stochastic gradient descent

Health and safety perspectives of graphene in wearables and hybrid materials

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Journal of Materials science & Technology 2023年第24期155卷 10-32页

作者： Premika Govindaraj Azadeh Mirabedini Xing Jin dennis Antiohos Nisa salim Phil Aitchison Jake Parker Franz Konstantin Fuss Nishar Hameed Faculty of science Engineering and Technology Swinburne University of Technology Hawthorn Melbourne VIC 3122 Australia Aerospace Engineering and Aviation School of Engineering RMIT University Bundoora Melbourne VIC 3083 Australia Institute for Frontier Materials Deakin University Geelong VIC 3216 Australia Imagine Intelligent Materials Sydney NSW 2018 Australia sparc Technologies Kent Town South Australia 5067 Australia Chair of Biomechanics Faculty of Engineering Science University of Bayreuth Bayreuth D-95440 Germany

The growing demand for smart wearables, coupled with the omnipresence of graphene due to its array of outstanding thermal, electrical, and mechanical properties, have driven the industry-led initiatives to develop lightweight, smart, and robust graphene-based wearable technologies. The substantial research and the increase in technology readiness levels (TRLs) of graphene-based technologies have led to the adoption of graphene in many industries. Graphene-based wearables are one such technology that involves closer interaction of graphene by the end-user. Despite this, understanding the toxicological risks associated with using graphene-based wearables is still in the fundamental stage. Herein, graphene-based wearables and industrial-scale fabrication techniques for the development of graphene-based wearables are reviewed. The main goal of the review is to initially evaluate the likelihood of user exposure to graphene from the wearable device and the potential health effects. The subsequent health risks based on graphene's physicochemical characteristics are also discussed. A framework to elucidate the risk is presented in terms of crucial exposure routes, possible graphene interactions, recent exposure assessments, detection removal techniques from the human body, and risk management protocols. It is hoped that this review may aid towards establishing a reasonable practice concerning the safe integration of graphene materials into wearables and facilitate their commercialization.

关键词： Graphene Wearables Composites Nanomaterials smart materials Health and safety

Degradation study on tin- and bismuth-based gas-diffusion electrodes during electrochemical CO_(2) reduction in highly alkaline media

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Journal of Energy Chemistry 2021年第11期30卷 367-376,I0008页

作者： Fabian Bienen Armin Lowe Joachim Hildebrand sebastian Hertle Dana schonvogel dennis Kopljar Norbert Wagner Elias Klemm Kaspar Andreas Friedrich Institute of Engineering Thermodynamics German Aerospace CenterPfaffenwaldring 38-4070569 StuttgartGermany Institute of Building Energetics Thermal Engineering and Energy StorageUniversity of StuttgartPfaffenwaldring 3170569 StuttgartGermany Institute of Technical Chemistry University of StuttgartPfaffenwaldring 5570569 StuttgartGermany Institute of Engineering Thermodynamics German Aerospace CenterCarl-von-Ossietzky-Straße 1526129 OldenburgGermany

This work investigated the degradation of tin – based gas-diffusion electrodes (GDE) and also a promising Bi2O3 GDE in electrochemical CO_(2) reduction in highly alkaline media which has not been studied before. The contributions of the electrode wetting (or flooding, if excessively) and catalyst leaching on the degradation were analyzed. Therefore, electrochemical impedance spectroscopy was used to monitor the wetted surface area of the GDE in combination with post-mortem analysis of the penetration depth by visualizing the electrolyte’s cation in the GDE cross-section. Furthermore, to reveal a possible degradation of the electrocatalyst, its distribution was mapped in the GDEs cross-section after operation while the catholyte was additionally analyzed via ICP-Ms. The results clearly demonstrate that the snO_(2) catalyst dissolves in the reaction zone inside the GDE and might be partially redeposited near the GDEs surface. since the redeposition process occurs only partially a steady loss of catalyst was observed impeding a clear distinction of the two degradation phenomena. Nevertheless, the deterioration of the electrode performance measured as faraday efficiency (FE) of the parasitic hydrogen evolution reaction (HER) qualitatively correlates with the differential double layer capacitance (Cdl). A significant difference of the rate of increase for the hydrogen FE and Cdl can be ascribed to the superposition of both above-mentioned degradation mechanisms. The demonstrated instability of snO_(2) contrasts with the behavior of Bi2O3 GDE which is stabilized during CO_(2) conversion by redeposition of the diluted dissolved species as metallic Bi which is active for the CO_(2) reduction reaction.

关键词： Electrochemical CO_(2)reduction Heterogeneous catalysis Gas-diffusion electrode Electrochemical impedance spectroscopy Catalyst leaching