检索结果-南通市图书馆

Galvanically induced potentials to enable minimal tribochemical wear of stainless steel lubricated with sodium chloride and ionic liquid aqueous solution

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Friction 2018年第2期6卷 230-242页

作者： Tobias AMANN Felix GATTI Natalie OBERLE Andreas KAILER jürgen RüHE Fraunhofer Institute for Mechanics of Materials IWM Institute for Macromolecular Chemistry University of Freiburg IMTEK-Department of Microsystems Engineering University of Freiburg

The effect of galvanically induced potentials on the friction and wear behavior of a 1 RK91 stainless steel regarding to tribocorrosion was investigated using an oscillating ball-on-disk tribometer equipped with an electrochemical cell. The aim of this investigation is to develop a water-based lubricant. Therefore 1 molar sodium chloride(NaCl) and 1% 1-ethyl-3-methylimidazolium chloride [C_2 mim][Cl] water solutions were used. Tribological performance at two galvanically induced potentials was compared with the non-polarized state: cathodic potential-coupling with pure aluminum- and anodic potential-coupling with pure copper. Frictional and electrochemical response was recorded during the tests. In addition, wear morphology and chemical composition of the steel were analyzed using scanning electron microscopy(SEM) and X-ray photoelectron spectroscopy(XPS), respectively. The galvanically induced cathodic polarization of the stainless steel surface results in electrochemical corrosion protection and the formation of a tribolayer. Cations from the electrolyte(sodium Na^+ and 1-ethyl- 3-methylimidazolium [C_2 mim]^+) interact and adhere on the surface. These chemical interactions lead to considerably reduced wear using 1 NaC l(86%) and 1% 1-ethyl-3-methylimidazolium chloride [C_2 mim][Cl](74%) compared to the nonpolarized system. In addition, mechanical and corrosive part of wear was identified using this electrochemical technique. Therefore this method describes a promising method to develop water-based lubricants for technical applications.

关键词： sliding wear tribochemistry potential controlled friction and wear galvanic coupling ionic liquids tribolayer formation

Enhancing production monitoring: A back allocation methodology to estimate well flow rates and assist well test scheduling

在线全文

学校读者我要写书评

暂无评论

Petroleum Research 2024年第3期9卷 369-379页

作者： G.S.Chaves V.j.M.Ferreira Filho Universidade Federal Do Rio de janeiro Brazil

Production flow rates are crucial to make operational decisions,monitor,manage,and optimize oil and gas *** rates also have a financial importance to correctly allocate production to fiscal purposes required by regulatory agencies or to allocate production in fields owned by multiple *** its significance,usually only the total field production is measured in real time,which requires an alternative way to estimate wells'*** address these challenges,this work presents a back allocation methodology that leverages real-time instrumentation,simulations,algorithms,and mathe-matical programming modeling to enhance well monitoring and assist in well test *** methodology comprises four modules:simulation,classification,error calculation,and *** modules work together to characterize the flowline,wellbore,and reservoir,verify simulation outputs,minimize errors,and calculate flow rates while honoring the total platform flow *** well status generated through the classification module provides valuable information about the current condition of each well(*** the well is deviating from the latest well test parameters),aiding in decision-making for well testing scheduling and *** effectiveness of the methodology is demonstrated through its application to a representative offshore oil field with 14 producing wells and two years of daily production *** results highlight the robustness of the methodology in properly classifying the wells and obtaining flow rates that honor the total platform flow ***,the methodology supports well test scheduling and provides reliable indicators for well *** uti-lizing real-time data and advanced modeling techniques,this methodology enhances production monitoring and facilitates informed operational decision-making in the oil and gas industry.

关键词： Production estimation Real-time production Production monitoring Back allocation Well test scheduling Flow rate estimation

A Compact Self-Isolated MIMO Antenna System for 5G Mobile Terminals

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer Systems Science & Engineering 2022年第9期42卷 919-934页

作者： Muhannad Y.Muhsin Ali j.Salim jawad K.Ali Microwave Research Group Department of Electrical EngineeringUniversity of TechnologyBaghdad10001Iraq Microwave Research Group Department of Communication EngineeringUniversity of TechnologyBaghdad10001Iraq

A compact self-isolated Multi Input Multi Output (MIMO) antennaarray is presented for 5G mobile phone devices. The proposed antenna systemis operating at the 3.5 GHz band (3400–3600 MHz) and consists of eight antennaelements placed along two side edges of a mobile device, which meets the currenttrend requirements of full-screen smartphone devices. Each antenna element isdivided into two parts, a front part and back part. The front part consists of anI-shaped feeding line and a modified Hilbert fractal monopole antenna, whereasthe back part is an L-shaped element shorted to the system ground by a0.5 mm short stub. A desirable compactness can be obtained by utilizing the Hilbert space-filling property where the antenna element’s overall planar size printedon the side-edge frame is just (9.57 mm × 5.99 mm). The proposed MIMO antenna system has been simulated, analyzed, fabricated and tested. Based on the selfisolated property, good isolation (better than 15 dB) is attained without employingadditional decoupling elements and/or isolation techniques, which increases system complexity and reduces the antenna efficiency. The scattering parameters,antenna efficiencies, antenna gains, and antenna radiation characteristics areinvestigated to assess the proposed antenna performance. For evaluating the proposed antenna array system performance, the Envelope Correlation Coefficients(ECCs), Mean Effective Gains (MEGs) and channel capacity are *** antenna and MIMO performances are evaluated to confirm the suitability of the proposed MIMO antenna system for 5G mobile terminals.

关键词： 5G applications compact antennas isolation techniques MIMO antennas mobile terminals self-isolated antennas

Breeding wheat for drought tolerance： Progress and technologies

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

journal of Integrative Agriculture 2016年第5期15卷 935-943页

作者： Learnmore Mwadzingeni Hussein Shimelis Ernest Dube Mark D Laing Toi j Tsilo College of Agriculture Engineering and Science University of KwaZulu-Natal/African Centre for Crop Improvement Scottsville 3209 South Africa Agricultural Research Council-Small Grain Institute (ARC-SGI) Bethlehem 9700 South Africa

Recurrent drought associated with climate change is among the principal constraints to global productivity of wheat（Triticum aestivum（L.） and T. turgidum（L.））. Numerous efforts to mitigate drought through breeding resilient varieties are underway across the world. Progress is, however, hampered because drought tolerance is a complex trait that is controlled by many genes and its full expression is affected by the environment. Furthermore, wheat has a structurally intricate and large genome. Consequently, breeding for drought tolerance requires the integration of various knowledge systems and methodologies from multiple disciplines in plant sciences. This review summarizes the progress made in dry land wheat improvement, advances in knowledge, complementary methodologies, and perspectives towards breeding for drought tolerance in the crop to create a coherent overview. Phenotypic, biochemical and genomics-assisted selection methodologies are discussed as leading research components used to exploit genetic variation. Advances in phenomic and genomic technologies are highlighted as options to circumvent existing bottlenecks in phenotypic and genomic selection, and gene transfer. The prospects of further integration of these technologies with other omics technologies are also provided.

关键词： drought tolerance genomic selection genotyping phenotyping wheat

Tectonics and Topography of the Tibetan Plateau in Early Miocene

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2014年第2期88卷 410-424页

作者： WU Zhenhan YANG Yan Patrick j. BAROSH WU Zhonghai ZHANG Yaoling Chinese Academy of Geological Sciences P.j. Barosh and Associates Institute of Geomechanics Chinese Academy of Geological Sciences

Early Miocene stratigraphy,major structural systems,magmatic emplacement,volcanic eruption,vegetation change and paleo-elevation were analyzed for the Tibetan Plateau after regional geological mapping at a scale of 1：250,000 and related researches,revealing much more information for tectonic evolution and topographic change of the high plateau caused by Indian-Asian continental *** deposits of dolostone,dolomite limestone,limestone,marl,sandstone and conglomerate of weak deformation formed extensively in the central Tibetan Plateau,indicating that vast lake complexes as large as 100,000-120,000 km2 existed in the central plateau during Early *** assemblages contained in the lacustrine strata indicate the disappearance of most tropical-subtropical broad-leaved trees since Early Miocene and the flourishing of dark needle-leaved trees during Early *** vegetation changes adjusted for latitude and global climate variations demonstrate that the central Tibetan Plateau rose to ca.4,000-4,500 m and the northeastern plateau uplifted to ca.3,500-4,000 m before the Early *** thrust and crustal thickening occurred in the areas surrounding central Tibetan Plateau in Early Miocene,formed Gangdise Thrust System （GTS） in the southern Lhasa block,Zedong-Renbu Thrust （ZRT） in the northern Himalaya block,Main Central Thrust （MCT） and Main Boundary Thrust （MBT） in the southern Himalaya block,and regional thrust systems in the Qaidam,Qilian,West Kunlun and Songpan-Ganzi *** basins formed in Early Miocene along major thrust systems,*** Siwalik basin along MCT,Yalung-Zangbu Basin along GTS and ZRT,southwestern Tarim depression along West Kunlun Thrust,and large foreland basins along major thrust systems in the northeastern margin of the *** volcanic eruptions formed in the Qiangtang,Hoh-Xil and Kunlun blocks,porphyry granites and volcanic eruptions formed in the Nainqentanglha and Gangdise Mts.,and leuco

关键词： Lacustrine deposits vast lakes elevation change regional thrust system Early Miocene Tibetan Plateau

EXPERIMENTAL RESEARCH AND NUMERICAL SIMULATION OF MOLD TEMPERATURE FIELD IN CONTINUOUS CASTING OF STEEL

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2006年第3期19卷 176-182页

作者： X.S. Zheng M.H. Sha j.Z. jin Research Center of Foundry Engineering Dnlian University of Technology Dalian 116024 China School of Materials Science and Engineering Anshan University of Science and Technology Anshan 114044 China

Mold is the heart of the continuous casting machine. Heat transfer and solidification in a water- cooled mold are the most important factors during the continuous casting of steel. For studying the temperature distribution of a mold wall, a simulated apparatus of mold was designed and experiments were performed by it. The measured results indicated that the mold wall temperature approaches the temperature of cooling-water. An equivalent thermal-conductivity coefficient was proposed and deduced on the basis of the conclusion of the experiments. This coefficient was applied to solve the heat transfer between the melt and cooling water, and to characterize the heat transfer capacity of the mold. By this equivalent thermal-conductivity coefficient, it is very easy and convenient to numerically simulate the solidification process of continuous casting. And the calculation results are in agreement with the experiments. The effects of custing speed and water flow rate on the mold temperature field were also discussed.

关键词： continuous casting mold temperature field numerical simulation

Spiking neural P systems with neuron division and budding

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2011年第8期54卷 1596-1607页

作者： P■UN Gheorghe PREZ-jIMNEZ Mario j. Department of Computer Science and Artificial Intelligence University of Sevilla Avda Reina Mercedes s/n 41012 Sevilla Spain Institute of Mathematics of the Romanian Academy PO Box 1-764 014700 Bucuresti Romania

Spiking neural P systems are a class of distributed and parallel computing models inspired by spiking *** this work,the features of neuron division and neuron budding are introduced into the framework of spiking neural P systems,which are processes inspired by neural stem cell division. With neuron division and neuron budding,a spiking neural P system can generate exponential work space in polynomial time as the case for P systems with active *** this way,spiking neural P systems can efficiently solve computationally hard problems by means of a space-time tradeoff,which is illustrated with an efficient solution to SAT problem.

关键词： natural computing membrane computing spiking neural P system neuron division

Diagnosing health in composite battery electrodes with explainable deep learning and partial charging data

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Energy and AI 2024年第2期16卷 256-268页

作者： Haijun Ruan Niall Kirkaldy Gregory j.Offer Billy Wu Dyson School of Design Engineering Imperial College LondonSW72AZLondonUK Centre for E-Mobility and Clean Growth Research Coventry UniversityCoventryCV15FBUK Department of Mechanical Engineering Imperial College LondonSW72AZLondonUK The Faraday Institution Harwell Science and Innovation CampusOX110RADidcotUK

Lithium-ion batteries with composite anodes of graphite and silicon are increasingly being used. However, their degradation pathways are complicated due to the blended nature of the electrodes, with graphite and silicon degrading at different rates. Here, we develop a deep learning health diagnostic framework to rapidly quantify and separate the different degradation rates of graphite and silicon in composite anodes using partial charging data. The convolutional neural network (CNN), trained with synthetic data, uses experimental partial charging data to diagnose electrode-level health of tested batteries, with errors of less than 3.1% (corresponding to the loss of active material reaching ∼75%). Sensitivity analysis of the capacity-voltage curve under different degradation modes is performed to provide a physically informed voltage window for diagnostics with partial charging data. By using the gradient-weighted class activation mapping approach, we provide explainable insights into how these CNNs work;highlighting regions of the voltage-curve to which they are most sensitive. Robustness is validated by introducing noise to the data, with no significant negative impact on the diagnostic accuracy for noise levels below 10 mV, thus highlighting the potential for deep learning approaches in the diagnostics of lithium-ion battery performance under real-world conditions. The framework presented here can be generalised to other cell formats and chemistries, providing robust and explainable battery diagnostics for both conventional single material electrodes, but also the more challenging composite electrodes.

关键词： Lithium-ion battery Composite electrode Silicon Degradation diagnostic Explainable deep learning Partial charging

Previous encapsulation response enhances within individual protection against fungal parasite in the mealworm beetle Tenebrio mofitor

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Insect Science 2013年第6期20卷 771-777页

作者： Indrikis Krams janina Daukste Inese Kivleniece Tatjana Krama Markus j. Rantala Institute of Ecology and Earth Sciences University of Tartu Tartu Estonia Institute of Systematic Biology University of Daugavpils Daugavpils Institute of Food Safety Animal Health and Environment BIOR Riga Latvia Department of Biology University of Turku Turku Finland

Immune defenses of insects show either broad reactions or specificity and durability of induced protection against attacking parasites and pathogens. In this study, we tested whether encapsulation response against nylon monofilament increases between two attempts of activation of immune system in mealworm beetles Tenebrio molitor, and whether previous exposure to nylon monofilament may also increase protection against an entomopathogenic fungus. We found that survival of beetles subjected to immune activation by nylon implant and subsequent fungal exposure a week later was significantly higher than survival of beetles which had been subjected to fimgal infection only. This result suggests that previous immune activation by the nylon implant may be considered as broad spectrum ＂immune priming＂ which helps to fight not only the same intruder but also other parasites.

关键词： antifungal protection ecological immunology encapsulation response,immune priming invertebrate immunity Tenebrio molitor