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Preparation Process and Properties of Porous Ecological Concrete

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武汉理工大学学报 2010年第17期32卷 256-260页

作者： lIANG l m YU H f PAN Z f Department of Civil Engineering Nanjing University of Aeronautics &AstronauticsNanjing 210016China

By using waste bricks as aggregate,a kind of porous ecological concrete was prepared and the mixing technique and its properties were studied. Effects of the cement paste fluidity on workability of the porous ecological concrete were investigated,and influences of the water-cement ratio,the aggregate-cement ratio and the aggregate size on compressive strength and porosity of the porous ecological concrete were also discussed. Results show that for preparation of the porous ecological concrete,the aggregates should be enveloped with neat cement paste,and recommended fluidity of the cement paste is 200～235 mm. With the increasing of the aggregate-cement ratio,porosity of the porous ecological concrete increases while the 28 d compressive strength decreases. With increasing of the water-cement ratio,porosity of the porous ecological concrete decreases. And relationship between compressive strength and water-cement ratio of the porous ecological concrete does not follow Bolomey's formula. As a result of this study the porous ecological concrete is prepared,its porosity is 38.93%,the water absorption is 11.39% and the compressive strength is 1.14 mPa.

关键词： aggregate-cement ratio water-cement ratio aggregate size on fluidity of cement paste porous ecological concrete process of paste encapsulated stone porosity compressive strength

Structural and photoluminescent properties of the mgGa_(2)O_(4):Co^(2+)ceramic compound revisited after two decades

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Journal of Advanced Ceramics 2015年第4期4卷 267-271页

作者： S.S.PEDRO m.A.f.m.DA SIlVA A.lÓPEZ,l.P.SOSmAN Instituto de física Universidade do Estado do Rio de JaneiroRJ 20550-900Brazil

In this work,we revisit and show how the structural and photoluminescent properties of the mgGa_(2)O_(4) ceramic compound have been kept unchanged for more than two *** obtained results confirm the high quality,radiative efficiency,and chemical stability of this ceramic,proving that the material is a strong candidate to be used in optical device applications with relatively long useful life.

关键词： ceramic compound cobalt solid-state reaction photoluminescence

Interest of D-dimer level,severity of COVID-19 and cost of management in Gabon

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World Journal of Critical Care medicine 2025年第1期14卷 91-99页

作者： Berthe A Iroungou Arnaud Nze O Helga m Kandet Y Neil-michel longo-Pendy Nina D mezogho-Obame Annicet-Clotaire Dikoumba Guignali l mangouka Unitémixte de Recherche Centre International de Recherches Médicales de Franceville et le Service de SantéMilitaireLibreville 20404EstuaireGabon AP-HP Health Economics Research UnitHtel Dieu HospitalParis 75004Ilede-FranceFrance laboratory Hôpital D'Instruction des Armées D'AkandaLibreville 20404EstuaireGabo Unitéde Recherche enÉcologie de la Santé Centre Interdisciplinaire de Recherches Médicales de FrancevilleFranceville 769Gabon laboratory Hôpital D'Instruction des Armées Omar Bongo OndimbaLibreville 20404EstuaireGabon Department of medecine Polyvalente Hôpital D'Instruction des Armées Omar Bongo OndimbaLibreville 20404EstuaireGabon

BACKGROUND Coronavirus disease 2019(COVID-19)is strongly associated with an increased risk of thrombotic events,including severe outcomes such as pulmonary *** D-dimer levels are a critical biomarker for assessing this *** Gabon,early implementation of anticoagulation therapy and D-dimer testing has been crucial in managing *** study hypothesizes that elevated Ddimer levels are linked to increased COVID-19 *** To determine the impact of D-dimer levels on COVID-19 severity and their role in guiding clinical *** This retrospective study analyzed COVID-19 patients admitted to two hospitals in Gabon between march 2020 and December *** study included patients with confirmed COVID-19 diagnoses and available D-dimer measurements at *** on demographics,clinical outcomes,D-dimer levels,and healthcare costs were ***-19 severity was classified as non-severe(outpatients)or severe(inpatients).A multivariable logistic regression model was used to assess the relationship between D-dimer levels and disease severity,with adjusted odds ratios(OR)and 95%*** A total of 3004 patients were included,with a mean age of 50.17 years,and the majority were female(53.43%).Elevated D-dimer levels were found in 65.81%of patients,and 57.21%of these experienced severe *** analysis showed that patients with elevated D-dimer levels had 3.33 times higher odds of severe COVID-19(OR=3.33,95%CI:2.84-3.92,Pmained significant in the multivariable analysis,adjusted for age,sex,and year of *** financial analysis revealed a substantial burden,particularly for uninsured *** D-dimer predicts COVID-19 severity and guides treatment,but the high cost of anticoagulant therapy highlights the need for policies ensuring affordable access in resource-limited settings like Gabon.

关键词： D-dimers COVID-19 management Disease severity Healthcare costs Gabon

Inversion of electrical mobility measurements using bipolar or unipolar chargers for the arbitrary distribution of channels

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Particuology 2015年第3期13卷 114-123页

作者： m.Domat f.E.Kruis N.l.Azong-Wara J.m.fernandez-Diaz Department of Physics University of OviedoC/Calvo Sotelos/nE-33007 OviedoSpain Institute of Technology for Nanostructures(NST) and Center for Nanointegration Duisburg-Essen(CENIDE) University of Duisburg-EssenBismarckstr.81D-47057 DuisburgGermany

The inversion of the particle size distribution from electrical mobility measurements is analyzed. Three different methods are adapted for a dot-matrix approach to the problem, especially for non-square or singular matrices, and applied to electrical mobility measurements from fixed or scanning voltages. mul- tiply charged particles, diffusion losses, arbitrary voltage steps and noise were considered, which results in non-adjoining and overlapping transfer functions. The individual contribution of the transfer func- tions in each size interval was geometrically estimated, which requires only its characteristic mobilities. The methodology is applied to mobility measurements from particles charged with unipolar and bipolar chargers. However, the method can be extrapolated to any charging method with a defined charge distribution, and retrieval of the singly charged particle distribution and mean charge from a tandem differential mobility analysis configuration was successfully demonstrated.

关键词： Tandem differential mobility analysisInverse problemRegularization methodsSize distributionTransfer functionUnipolar charger

Prediction of the effectiveness of rolling dynamic compaction using artificial neural networks and cone penetration test data

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岩石力学与工程学报 2019年第1期38卷 153-170页

作者： R.A.T.m.Ranasinghe m.B.Jaksa f.Pooya Nejad Y.l.Kuo School of Civil Environmental and Mining EngineeringUniversity of Adelaide

Rolling Dynamic Compaction(RDC),which is a ground improvement technique involving non-circular modules drawn behind a tractor,has provided the construction industry with an improved ground compaction capability,especially with respect to a greater influence depth and a higher speed of compaction,resulting in increased productivity. However,to date,there is no reliable method to predict the effectiveness of RDC in a range of ground conditions. This paper presents a new and unique predictive tool developed by means of artificial neural networks(ANNs) that permits a priori prediction of density improvement resulting from a range of ground improvement projects that employed 4-sided RDC modules;commercially known as"impact rollers". The strong coefficient of correlation(i.e. R>0.86) and the parametric behavior achieved in this study indicate that the model is successful in providing reliable predictions of the effectiveness of RDC in various ground conditions.

关键词： soil mechanics rolling dynamic compaction artificial neural networks cone penetration test ground improvement

Non-intrusive data-driven ROm framework for hemodynamics problems

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Acta mechanica Sinica 2021年第7期37卷 1183-1191,I0003页

作者： m.Girfoglio l.Scandurra f.Ballarin G.Infantino f.Nicolo A.montalto G.Rozza R.Scrofani m.Comisso f.musumeci Area di matematica mathLabSISSAScuola Internazionale Superiore di Studi AvanzatiTriesteItaly modelli matematici e Simulazioni Numeriche Collegio di Ingegneria MatematicaPolitecnico di TorinoTorinoItaly Unit Operativa Complessa di Cardiochirurgia e Chirurgia dei Trapianti Azienda Ospedaliera San CamilloRomeItaly Dipartimento di Cardiochirurgia Azienda Ospedaliera FBF Luigi SaccoMilanItaly

Reduced order modeling(ROm)techniques are numerical methods that approximate the solution of parametric partial differential equation(PED)by properly combining the high-fidelity solutions of the problem obtained for several configurations,*** several properly chosen values of the physical/geometrical parameters characterizing the *** starting from a database of high-fidelity solutions related to a certain values of the parameters,we apply the proper orthogonal decomposition with interpolation(PODI)and then reconstruct the variables of interest for new values of the parameters,*** values from the ones included in the ***,we present a preliminary web application through which one can run the ROm with a very user-friendly approach,without the need of having expertise in the numerical analysis and scientific computing *** case study we have chosen to test the efficiency of our algorithm is represented by the aortic blood flow pattern in presence of a left ventricular(lVAD)assist device when varying the pump flow rate.

关键词： Non intrusive model reduction Data-driven techniques Hemodynamics lVAD Web computing

Temperature Effect on Early Oxidation Behavior of NiCoCrAlY Coatings: microstructure and Phase Transformation

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Acta metallurgica Sinica(English letters) 2022年第6期35卷 975-984页

作者： A.Ullah A.Khan Z.B.Bao Y.f.Yang m.m.Xu S.l.Zhu f.H.Wang University of Chinese Academy of Sciences Beijing 100049China Shi-Changxu Innovation Center for Advanced materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key laboratory of Green fabrication and Surface Technology of Advanced metal materials Ministry of EducationSchool of Materials Science and EngineeringAnhui University of TechnologyMaanshan 243000China Institute of Advanced Wear and Corrosion Resistant and functional material Jinan UniversityGuangzhou 510632China Shenyang National laboratory for materials Science Northeastern UniversityShenyang 110819China

Initial oxidation behavior of NiCoCrAlY coating prepared by arc-ion plating has been studied in air at 900, 1000 and 1100 ℃. The results showed that phase transformation from transient θ-Al_(2)O_(3) to α-Al_(2)O_(3) was highly related to the temperature and oxidation time. The oxide scale in the initial stage was mainly composed of θ-Al_(2)O_(3) at 900 ℃. Instead, more amount of α-Al_(2)O_(3) emerged out with increasing oxidation temperature. The elemental distribution after oxidation confirmed that faster chromium diffusion to the oxide scale played an important role in the speedy transformation from θ-Al_(2)O_(3) to α-Al_(2)O_(3). Y segregation at scale/coating interface resulted in less cavity formation and hence improved the oxide scale adherence.

关键词： mCrAlY coating Phase transformation Isothermal oxidation Temperature effect

lineament analysis as a seismic precursor:The El mayor Cucapah earthquake of April 4,2010(mW7.2),Baja California,mexico

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Geodesy and Geodynamics 2023年第2期14卷 121-129页

作者： Rosendo Romero-andrade manuel E.Trejo-Soto Karan Nayak Daniel Hernández-andrade Naccieli Bojorquez-Pacheco faculty of Earth and Space Sciences Autonomous University of Sinaloa80013Culiacan RosalesSinaloaMexico

An earthquake called the mW7.2“El mayor Cucapah”earthquake on April 4,2010 has been analyzed for seismic *** changes in the lineament system concerning its pattern and time intervals were analyzed during the earthquake preparation period and occurrence using the automated lineament detection *** landsat 5 Tm images were processed using lESSA and ADAlGEO software obtaining similar *** statistical analysis revealed the stress accumulation due to plate interaction during earthquake *** study shows that the number of extracted lineaments changes rapidly about 23 months before the earthquake,and the systems return to the initial stage after 23 *** lineaments coincide with the extension of the San Andreas fault as NW direction is the dominant ***,it can be concluded that the featural changes within the Rose diagram corresponding to the different strokes direction along with oriented elongation lines as disclosed in the present study using satellite images could be identified as a mid-term and/or short-term precursors of the ***,even though the dynamism of the El mayor Cucapah earthquake is found in the extracted lineaments,it is possible to isolate more significant earthquakes even if new ones appear near the ***,using two algorithms for lineament detection allows for the tectonics to corroborate the obtained lineaments and dynamism.

关键词： lineament analysis Earthquake landsat images Seismic precursor

mineralogy of Selected Paddy Soils in Southeastern China

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Pedosphere 1997年第4期7卷 289-296页

作者： f.l.WANG P.m.HUANG DepartmentofSoilScience UniversityofSaskatchewanSaskatoonS7N5A8（Canada） DepartmentofSoilScience Uni

limited information is available concerning the mineralogy of paddy soils in the southeastern *** chemical methods in conjunction with X-ray diffractometry, we studied the mineral composition of three paddy soils: Jinghua (paddy soil on Quaternary red clay), fuyang (Hapl-percogenic loamy paddy soil), and Shaoxing (gleyic clayey paddy soil). All the soils contained quartz, mica, vermiculite, chlorite and kaolinite, and the distribution of these minerals varied with soil particle size fractions. The clay fraction of the f’uyang and Shaoxing soils also contained smectite. Although X-ray data did not show the presence of smectite in the Jinghua soil, this mineral was identified by the chemical method, suggesting a transitional property of the mineral in the soil. Hydroxy-Al interlayered minerals were also present in the clay *** amount of smectite in the soils was 31.6 (Shaoxing), 16.5 (fuyang), and 21.4 (Jinghua) g kg-1; for vermiculite it was 33.3 (Shaoxing), 16.5 (fuyang), and 8.5 (Jinghua) g kg-1. Smectite was only found in the clay fraction. In contrast, amounts of vermiculite in soil particle size fractions were 3.0～11.4 (sand),2.1～6.0 (coarse silt), 4.6～18.9 (medium silt), 0.9～40.0 (fine silt), and 17.0～108 (clay) g kg-1. The amount of noncrystalline aluminosilicates in the soils in g kg-1 decreased in the order: Shaoxing (2.4) > Jinghua (1.9) > fuyang (1.7). This study has provided useful mineralogical information that is fundamental in future developmellt of management strategies of the soils.

关键词： hydroxy-Al interlayered minerals mineralogy noncrystalline materials paddy soils