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XPS characterization and corrosion resistance of cerium-treated magnesium coatings

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Rare Metals 2011年第4期30卷 368-373页

作者： Samia Ben Hassen Latifa Bousselmi Patrice berot El mustafa Rezrazi Ezzeddine Triki Unité de Recherche Corrosion & Protection des Métalliques ENITBP 37Tunis-BelvédèreTunisie Institut UTINAM CNRS UMR 6213Université de Franche-Comté16 route de Gray 25030 Besanon CedexFrance Laboratoire Traitement et Recyclage des Eaux CERTEBorj CedriaTunisie

Cerium conversion treatment was applied on magnesium coatings in a solution containing CeC13. The composition ot the cenum conversion layer on magnesium was investigated using X-ray photoelectron spectroscopy （XPS）, It was revealed that the composition predominately consisted of a three-valent state cerium compound with a relative abundance around 90%. Some of Ce^3＋ was oxidized to Ce^4＋. Electrochemical impedance spectroscopy results revealed that the total impedance of cerium-treated samples increased for a short immersion time in NaC1 solution before coating deteriorating. This deterioration was due to the coating porosity increasing and the breakdown of the conversion layer

关键词： cerium compounds magnesium coatings X-ray photoelectron spectroscopy corrosion resistance

Improving the utility of locally differentially private protocols for longitudinal and multidimensional frequency estimates

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Digital Communications and Networks 2024年第2期10卷 369-379页

作者： Héber H.Arcolezi Jean-François Couchot Bechara Al Bouna Xiaokui Xiao Inria andÉcole Polytechnique(IPP) PalaiseauFrance Femto-ST Institute Univ.Bourg.Franche-ComtéUBFCCNRSBelfortFrance TICKET Lab. Antonine University Hadat-BaabdaBaabdaLebanon School of Computing National University of SingaporeSingaporeSingapore

This paper investigates the problem of collecting multidimensional data throughout time(i.e.,longitudinal studies)for the fundamental task of frequency estimation under Local Differential Privacy(LDP)*** to frequency estimation of a single attribute,the multidimensional aspect demands particular attention to the privacy ***,when collecting user statistics longitudinally,privacy progressively ***,the“multiple”settings in combination(i.e.,many attributes and several collections throughout time)impose several challenges,for which this paper proposes the first solution for frequency estimates under *** tackle these issues,we extend the analysis of three state-of-the-art LDP protocols(Generalized Randomized Response–GRR,optimized Unary Encoding–oUE,and Symmetric Unary Encoding–SUE)for both longitudinal and multidimensional data *** the known literature uses oUE and SUE for two rounds of sanitization(***),i.e.,L-oUE and L-SUE,respectively,we analytically and experimentally show that starting with oUE and then with SUE provides higher data utility(i.e.,L-oSUE).Also,for attributes with small domain sizes,we propose Longitudinal GRR(L-GRR),which provides higher utility than the other protocols based on unary ***,we also propose a new solution named Adaptive LDP for Longitudinal and multidimensional FREquency Estimates(ALLoMFREE),which randomly samples a single attribute to be sent with the whole privacy budget and adaptively selects the optimal protocol,i.e.,either L-GRR or *** shown in the results,ALLoMFREE consistently and considerably outperforms the state-of-the-art L-SUE and L-oUE protocols in the quality of the frequency estimates.

关键词： Local differential privacy Discrete distribution estimation Frequency estimation multidimensional data Longitudinal studies

The effect of climate factors on the size of forest wildfires(case study:Prague-East district,Czech Republic)

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Journal of Forestry Research 2022年第4期33卷 1291-1300页

作者： Zohreh Mohammadi Peter Lohmander Jan Kašpar Roman berčák Jaroslav Holuša Robert Marušák Faculty of Forestry and Wood Sciences Czech University of Life Sciences PragueKamýcká12916500 Praha-SuchdolCzech Republic optimal Solutions in Cooperation with Linnaeus University UmeaSweden

This paper presents a new approach to identifying the climate variables that influence the size of the area burned by forest *** linear regression was used in combination with nonlinear variable transformations to determine relevant nonlinear forest wildfire size *** from the Prague-East District of the Czech Republic was used for model *** burned forest area was hypothesized as a function of water vapor pressure,air temperature and wind *** speed was added to enhance predictions of the size of forest wildfires,and further improvements to the utility of prediction methods were added to the regression *** results show that if the air temperature increases,it may contain less water and the fuel will become *** size of the burned area then *** the relative humidity in the air increases and the wind speed decreases,the size of the burned area is *** model suggests that changes in the climate factors caused by ongoing climate change could cause significant changes in the size of wildfire in forests.

关键词： Climatic variables Burned forest area Climate change multiple linear regression

Successive quadratic programming multiuser detector

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Journal of Systems Engineering and Electronics 2007年第1期18卷 8-13页

作者： mu Xuewen Zhang Yaling Liu Sanyang Dept. of Applied Mathematics Xidian Univ. Xi'an 710071 E R. China Dept. of Computer Science and Technology Xi'an Univ. of Science and Technology Xi'an 710054 P. R. China

Based on the semidefinite programming relaxation of the CDMA maximum likelihood multiuser detection problem, a detection strategy by the successive quadratic programming algorithm is presented. Coupled with the randomized cut generation scheme, the suboptimal solution of the multiuser detection problem in obtained. Compared to the interior point methods previously reported based on semidefmite programming, simulations demonstrate that the successive quadratic programming algorithm often yields the similar ber performances of the multiuser detection problem. But the average CPU time of this approach is significantly reduced.

关键词： Code division multiple access multiuser detection Semidefinite programming Successive quadratic programming.

Crown and leaf traits as predictors of subtropical tree sapling growth rates

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Journal of Plant Ecology 2017年第1期10卷 136-145页

作者： Ying Li Wenzel Kröber Helge Bruelheide Werner Härdtle Goddert von oheimb Faculty of Sustainability Leuphana University LüneburgInstitute of EcologyScharnhorststraße 1D-21335 LüneburgGermany Martin Luther University Halle Wittenberg Institute of Biology/Geobotany and Botanical GardenAm Kirchtor 1D-06108 HalleGermany German Centre of Integrative Biodiversity Research(iDiv)Halle-Jena-Leipzig Deutscher Platz 5eD-04103 LeipzigGermany Faculty of Environmental Sciences Technische Universität DresdenInstitute of General Ecology and Environmental ProtectionPienner Straße 7D-01735 TharandtGermany

Aims Growth rates of plants are driven by factors that influence the amount of resources captured and the efficiency of resource *** trees,the amount of light captured and the efficiency of light use strongly depends on crown characteristics and leaf *** theory predicts that both crown and leaf traits affect tree growth,few studies have yet to integrate these two types of traits to explain species-specific growth *** 37 broad-leaved tree species of subtropical forests in SE China,we investigated how interspecific differences in wood volume growth rates were affected by crown and leaf *** tested the hypotheses that(i)larger crown dimensions promote growth rates,(ii)species-specific growth rates are positively related to leaf stomatal conductance,leaf water potential and leaf chemical components,and negatively related to leaf C/N and leaf toughness and(iii)the two sets of traits better explain growth rates in combination than either *** our study was conducted in a large-scale forest Biodiversity and Ecosystem Functioning experiment in China(BEF-China),located in a mountainous region in Jiangxi *** related 17 functional traits(two crown dimension and three crown structure traits;six physiological and six morphological leaf traits)to the mean annual growth rate of wood volume of young trees of the studied *** between crown and leaf traits were analyzed using principal component *** linear regression analysis was used to test the effect of each trait *** used multiple regression analysis to establish the relationship of growth rate to each set of traits(crown traits,physiological and morphological leaf traits)and to the combination of all types of *** coefficients of determination(R^(2)_(adj))of the best multiple regression models were compared to determine the relative explanatory power of crown and leaf traits and a combination of *** Findings The species-spec

关键词： BEF China crown characteristics physiological leaf traits morphological leaf traits wood volume

Fatty acids derived from oviposition systems guide female black soldier flies(Hermetia illucens)toward egg deposition sites

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Insect Science 2024年第4期31卷 1231-1248页

作者： Patrick Klüber Emna Arous Jeanny Jerschow Marco Fraatz Daniel Bakonyi Martin Rühl Holger Zorn Department Bioresources Fraunhofer Institute for Molecular Biology and Applied EcologyGiessenGermany Institute of Food Chemistry and Food Biotechnology Justus Liebig University GiessenGiessenGermany

The black soldier fly,Hermetia illucens,comes with big promises for industrial purposes since its larvae feed polyphagously on a broad spectrum of organic ***,research focusing on adult flies is scarce,which is inconsistent with their reproductive relevance within the rearing *** particular,directed oviposition is a challenge in artificial ***,decomposing organic matter is commonly used as oviposition substrate,which has extensive potential for improvement in view of the lack of standardization and the risk of microbial ***,we identified three fatty acids and one fatty acid methyl ester derived from the surface of old oviposition sites and targeted to elucidate their effect on preference behavior and oviposition site selection using Y-olfactometry and prepared oviposition sites,*** to tetradecanoic acid attracted gravid females and stimulated oviposition most strongly,while decanoic acid demonstrated a repulsive *** kept in mixed-sex populations were attracted by tetradecanoic acid,resulting in a higher egg mass found in the compound box(3.0–11.4 fold),a≥2.3 fold reduction of nonspecifically deposited eggs,and the highest total egg ***,decanoic and dodecanoic acid caused females to lay a greater proportion of eggs nonspecifically outside both *** data suggest that fatty acids,especially tetradecanoic acid,are important cues for oviposition site selection in black soldier *** order to achieve a directed oviposition behavior,the role of further short-and long-chain fatty acids as attractants should be examined.

关键词： black soldier fly Hermetia illucens fatty acids insects as food and feed oviposition oviposition site selection tetradecanoic acid

The effect of temperature on ionic liquid modified Fe-N-C catalysts for alkaline oxygen reduction reaction

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Journal of Energy Chemistry 2022年第5期31卷 324-329页

作者： Thomas Wolker Kai Brunnengräber Ioanna Martinaiou Nick Lorenz Gui-Rong Zhang Ulrike I.Kramm Bastian J.M.Etzold Department of Chemistry Ernst-Berl-Institut für Technische und Makromolekulare ChemieTechnical University of Darmstadt64287 DarmstadtGermany Department of Chemistry Catalysts and Electrocatalysts GroupTechnical University of Darmstadt64287 DarmstadtGermany Graduate School of Excellence Energy Science and Engineering Technical University of Darmstadt64287 DarmstadtGermany Department of Materials and Earth Sciences Technical University of Darmstadt64287 DarmstadtGermany School of Chemical Engineering and Technology Tiangong UniversityTianjin 300387China

Modifying solid catalysts with an ionic liquid layer is an effective approach for boosting the performance of both Pt-based and non-precious metal catalysts toward the oxygen reduction reaction. While most studies operated at room temperature it remains unclear whether the IL-associated boosting effect can be maintained at elevated temperature, which is of high relevance for practical applications in low temperature fuel cells. Herein, Fe-N-C catalysts were modified by introducing small amounts of hydrophobic ionic liquid, resulting in boosted electrocatalytic activity towards the alkaline oxygen reduction reaction at room temperature. It is demonstrated that the boosting effect can be maintained and even strengthened when increasing the electrolyte temperature up to 70℃. These findings show for the first time that the incorporation of ionic liquid is a suited method to obtain advanced noble metal-free electrocatalysts that can be applied at operating temperature condition.

关键词： oxygen reduction reaction Non-precious metal catalyst Ionic liquid Fe-N-C catalyst Temperature effect

Minimal Critical Sets of Refined Inertias for Irreducible Sign Patterns of order 2

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Advances in Linear Algebra & Matrix Theory 2013年第2期3卷 7-10页

作者： ber-Lin Yu Faculty of Mathematics and Physics Huaiyin Institute of Technology Huai’an China

Let S be a nonempty, proper subset of all refined inertias. Then, S is called a critical set of refined inertias for ireducible sign patterns of order n if is sufficient for any sign pattern A to be refined inertially arbitrary. If no proper subset of Sis a critical set of refined inertias, then S is a minimal critical set of refined inertias for sign patterns of order n . In this paper, all minimal critical sets of refined inertias for irreducible sign patterns of order 2 are identified. As a by-product, a new approach is presented to identify all minimal critical sets of inertias for irreducible sign patterns of order 2.

关键词： Associated Digraph Inertially Arbitrary Sign Pattern Refined Inertia Critical Set of Refined Inertias

Bit-Interleaved Polar Coded Modulation with Iterative Successive Cancellation List Decoding

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China Communications 2022年第5期19卷 54-68页

作者： Hang mu Zheng Ma George K.Karagiannidis Panagiotis D.Diamantoulakis The 10th Research Institute of China Electronics Technology Group Corporation Chengdu 610036SichuanChina the School of Information Science and Technology Southwest Jiaotong UniversityChengdu 610036SichuanChina the Departmentof Electrical and Computer Engineering Aristotle University of ThessalonikiThessaloniki 54124Greece

This paper introduces bit-interleaved polar coded modulation with iterative detection/decoding(BIPCM-ID).In order to enable the soft output of successive cancellation list(SCL)decoding,two types of re-encoders are proposed,namely the max-re-encoder and min-re-encoder,*** the iterative decoding,we analytically verify that the average mutual information(AMI)between the transmitted and decoded symbols can approach the Shannon bound with the proposed ***,bit error rate(ber)and block error rate(BLER)in single-user and multi-user scenarios are ***,simulation results show that the performance of BIPCMID outperforms other bit-interleaved coded modulation(BICM)systems with LDPC and Turbo codes,while also reducing the computational complexity.

关键词： BIPCM-ID Polar code SCMA Reencoder SCL AMI