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A Comparison of Semi-Lagrangian and Lagrange-Galerkin hp-FEM Methods in Convection-Diffusion Problems

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Communications in Computational Physics 2011年第4期9卷 1020-1039页

作者： Pedro Galan del sastre..odolfo Bermejo Departamento de Matematica Aplicada al Urbanismo a la Edificacion y al Medio AmbienteE.T.S.A.M.Universidad Politecnica de MadridAvda.Juan de Herrera 428040 MadridSpain Departamento de Matematica Aplicada E.T.S.I.I.Universidad Politecnica de MadridC/Jose Gutierrez Abascal 228006 MadridSpain

We perform a comparison in terms of accuracy and CPU time between second order BDF semi-Lagrangian and Lagrange-Galerkin schemes in combination with high order finite element *** numerical results show that for polynomials of degree 2 semi-Lagrangian schemes are faster than Lagrange-Galerkin schemes for the same number of degrees of freedom,however,for the same level of accuracy both methods are about the same in terms of CPU *** polynomials of degree larger than 2,Lagrange-Galerkin schemes behave better than semi-Lagrangian schemes in terms of both accuracy and CPU time;specially,for polynomials of degree 8 or ***,we have performed tests on the parallelization of these schemes and the speedup obtained is quasi-optimal even with more than 100 processors.

关键词： Navier-Stokes equations convection-diffusion equations semi-Lagrangian LagrangeGalerkin second order backward difference formula hp-finite element method

Adsorption of neodymium,terbium and dysprosium using a synthetic polymer-based magnetic adsorbent

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Journal of Rare Earths 2023年第11期41卷 1796-1804,I0006页

作者： Hamedreza Javadian Mehdi Taghavi Montserrat Ruiz Inderjeet Tyagi Majid Farsadrooh Ana Maria sastre Department of Chemical Engineering ETSEIBUniversitat Politècnica de CatalunyaDiagonal 64708028BarcelonaSpain Department of Chemistry Faculty of ScienceShahid Chamran University of Ahvaz61357-43337Iran Department of Chemical Engineering EPSEVGUniversitat Politècnica de CatalunyaAv.Víctor Balaguers/n08800Vilanova i la GeltrúSpain Centre for DNA Taxonomy Molecular Systematics DivisionZoological Survey of IndiaKolkata700053India Renewable Energies Research Laboratory Department of ChemistryFaculty of ScienceUniversity of Sistan and BaluchestanP.O.Box 98135674ZahedanIran

In this study,a polyamide with methine-thiophene and pyrimidine linkages(poly(pyrimidine-thiophene-amide)(PPTA))was ***,magnetic PPTA(M-PPTA)was synthesized using the hydrothermal *** products were analyzed by Fourier-transform infrared spectroscopy(FTIR),nuclear magnetic resonance(NMR),X-ray diffraction(XRD),thermogravimetric analysis(TGA),field-emission scanning electron microscopy(FE-SEM),and a vibrating-sample magnetometer(VSM).The nanocomposite exhibits a saturation magnetization of 50.44 emu/g recorded by VSM *** ability of M-PPTA to bind dysprosium(Dy^(3+)),terbium(Tb^(3+)),and neodymium(Nd^(3+))was *** 0.15 g of M-PPTA to test the adsorption of the rare earth elements(50 mg/L)at pH=5.5,the percentage of adsorption for Dy^(3+),Tb^(3+),and Nd^(3+)is 98.41%,97.48%and 95.67%,***-second-order(PSO)significantly fits the adsorption kinetic *** equation was used to describe the adsorption equilibrium data of Dy^(3+)and Tb^(3+),while Langmuir model was used to simulate Nd^(3+)adsorption *** the temperature leads to an increase in the performance of M-PPTA,and an endothermic adsorption process was confirmed by the positive values ofΔ*** four adsorption-desorption cycles,the efficiency of adsorption of Dy^(3+),Tb^(3+),and Nd^(3+)by M-PPTA is88.75%,86.37%,and 84.64%,*** antagonism effect is observed for the adsorption of the individual ions in a ternary solution.

关键词： Polyamide Lanthanides Magnetic nanocomposite Adsorption Rare earth elements

The use of remote sensing to detect the consequences of erosion in gypsiferous soils

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International Soil and Water Conservation Research 2020年第4期8卷 383-392页

作者： Maria Jose Marques Ana Alvarez Pilar Carral Blanca sastre..amón Bienes Geology and Geochemistry Department Autonomous University of MadridCalle Francisco Tomás y Valiente728040MadridSpain Department of Applied Research and Agrarian Extension IMIDRAFinca El Encín.Carretera A-2Km 38.8.Alcaláde Henares28800MadridSpain

Tillage practices on sloping ground often result in unsustainable soil losses impairing soil functions such as crop productivity,water and nutrients storage,and soil organic carbon(SOC)sequestration.A sloping olive grove(10%)was planted in shallow gypsiferous soils in *** was managed by minimum tillage;the most frequent management practice in central *** consequences of erosion were studied in soil samples(at 0-10,10-20,and 20-30 cm depths)by analyzing SOC,available water and gypsum content,and by detecting spectral signatures using an ASD FieldSpecPro(R)VIS/*** Brightness index(BI),Shape index(FI),and Normalized Difference Vegetation Index(NDVI)were derived from the ASD spectral signatures and from remote sensing(Sentinel-2 image)*** development of these young olive trees was estimated from the measured diameter of the trunks(17±18 cm diameter).In 20-30 cm of the soil,the carbon stock(38±18 Mg ha-1)as well as the available water content(12±6%)was scarce,affecting the productivity of the olive *** above-mentioned indices obtained from the laboratory samples and the pixels of the Sentinel-2 image were significantly(p<0.01)correlated,with a correlation coefficient of around *** BI was related to the gypsum content and the slope of the *** FI was related to the carbon and water *** NDVI derived from the satellite image identified the influence of soil degradation on the trees and the carbon *** spatialtemporal changes of the indices might help in tracking soil changes over time.

关键词： Tillage Erosion NDVI Gypsum Remote sensing Soil color

Effect of calcination temperature on structural properties and catalytic activity in oxidation reactions of LaNiO_3 perovskite prepared by Pechini method

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Journal of Rare Earths 2012年第3期30卷 210-216页

作者： K. Rida M.A. Pea E. sastre... Martínez-Arias Laboratory for the Study of Interactions Between Materials and Their Environment University of Jijel Institute of Catalysis and Petroleum-Chemistry CSIC C/Marie Curie 2 Campus de Cantoblanco 28049 Madrid Spain

The study presented the preparation of the perovskite oxide LaNiO3 by the complex citrate method, paying particular attention to evolution of its formation from the amorphous precursor with varied calcination temperatures. The products obtained after heat treatment under air between 200 and 800 ℃ were characterized by X-ray diffraction （XRD）, thermogravimetric and differential thermal analysis （TG-DTA）, Fourier transform infrared spectroscopy （FTIR）, SBET measurements and X-ray photoelectron spectroscopy （XPS）. The results showed the formation of a single phase with perovskite structure from ca. 550 ℃. Tests on the two catalytic oxidation reactions of C3H6 and CO over the system calcined between mentioned temperatures were examined on the basis of characterization results and showed that optimum catalytic properties for such reactions were achieved for the perovskite calcined at 600 ℃. In turn, correlations between redox and catalytic properties were established on the basis of thermogravimetric temperature programmed reduction （TPR） analysis.

关键词： LaNiO3 perovskite Pechini SOFC C3H6 and CO combustion rare earths

Persistence and growth of faecal culturable bacterial indicators in water column and sediments of Vidy Bay,Lake Geneva,Switzerland

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Journal of Environmental Sciences 2009年第1期21卷 62-69页

作者： POTE John HALLER Laurence KOTTELAT Régis sastre..incent ARPAGAUS Philippe WILDI Walter University of Geneva F.-A. Forel Institute10 route de Suisse1290 VersoixSwitzerland

The aims of this study was to investigate the persistence and the growth of culturable bacterial indicators （CBI） including total coliforms （TC） and faecal coliforms represented by Escherichia coli, enterococcus （ENT）, and aerobic mesophilic bacteria （AMB） in the surface sediments and the water column of Vidy Bay fLake Geneva, City of Lausanne, Switzerland）. The study was carded out for 60 d using microcosms containing Sewage Treatment Plant （STP） effluent and nonsterile water without CBI, as well as contaminated and non-contaminated sediments. The effects of water temperature and of organic matter associated with sediments on the survival of CBI in the sediments and the water column were observed. The number of CBI colonies in the contaminated sediments of Vidy Bay and in the STP effluent was almost identical in the order of 10^5-10^7, 10^4-10^6, 10^5-10^5, and 10^4-10^7 CFU/100 g sediment or/100 mL water for TC, E. coli, ENT, and AMB respectively. A degradation of CBI was observed in the sediments where organic mater content was low and in the water column at a temperature of 10℃ after 5 d of experimentation. In addition, a growth of CBI was observed in the sediment which is rich in organic matter at 20℃. The results of this study indicate：（1） the higher concentrations of the CBI observed in different points in the water column of Vidy Bay may not be explained only by the recent contribution of the three potential sources of the Bay contamination including STP and the Chamberonne and Flon Rivers, but also by the persistence, removal from sediment and multiplication of CBI in the sediment and water column; （2） the sediment of Vidy Bay constitute a reservoir of CBI and can even support their growth; and （3） the CBI not only survive in sediments, but also can be remobilized and increased in the water column, therefore, it become a permanent microbiological pollution in Vidy Bay.

关键词： Lake Geneva faecal pollution persistence multiplication human health risk

Humans Are Not Machines—Anthropocentric Human–Machine Symbiosis for Ultra-Flexible Smart Manufacturing

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Engineering 2021年第6期7卷 734-737页

作者： Yuqian Lu Juvenal sastre..drados Saahil Shivneel Chand Lihui Wang Department of Mechanical Engineering The University of AucklandAuckland 1142New Zealand Department of Production Engineering KTH Royal Institute of TechnologyStockholm 10044Sweden

*** The real question is not whether machines think but whether men *** Frederic Skineer Dedicated manufacturing systems are fading out as future manufacturing(i.e.,Industry 4.0[1])demands ultra-flexible smart manufacturing systems that can self-adapt to production process changes resulting from the varied batch sizes of personalized products[2–4].The manufacturing shop-floor can become an unstructured environment where manufacturing systems and processes change their configurations dynamically via adaptive near-real-time *** emerging trend to make manufacturing flexible and reconfigurable is to introduce collaborative machines that work alongside humans with high productivity[5-7].

关键词： Human batch sizes

Role of cetuximab in first-line treatment of metastatic colorectal cancer

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World Journal of Gastroenterology 2014年第15期20卷 4208-4219页

作者： Miguel Jhonatan Sotelo Beatriz García-Paredes Carlos Aguado Javier sastre..duardo Díaz-Rubio Center affiliate to the "Red Temática de Investigación Cooperativa (RD12/0036/006)" Instituto Carlos ⅢSpanish Ministry of Economy and Competitivity. Oncology DepartmentHospital Clínico San Carlos28040 MadridSpain Department of Medicine School of MedicineUniversidad Complutense de Madrid28040 MadridSpain

The treatment of metastatic colorectal cancer(mCRC)has evolved considerably in the last decade,currently allowing most mCRC patients to live more than two *** antibodies targeting the epidermal growth factor receptor(EGFR)and vascular endothelial growth factor play an important role in the current treatment of these ***,only antibodies directed against EGFR have a predictive marker of response,which is the mutation status of v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog(KRAS).Cetuximab has been shown to be effective in patients with KRAS wild-type *** CRYSTAL study showed that adding cetuximab to FOLFIRI(regimen of irinotecan,infusional fluorouracil and leucovorin)significantly improved results in the first-line treatment of KRAS wildtype ***,results that evaluate the efficacy of cetuximab in combination with oxaliplatin-based chemotherapy in this setting are *** the other hand,recent advances in the management of colorectal liver metastases have improved survival in these *** cetuximab to standard chemotherapy increases the response rate in patients with wild-type KRAS and can thus increase the resectability rate of liver metastases in this group of *** this paper we review the different studies assessing the efficacy of cetuximab in the first-line treatment of mCRC.

关键词： Cetuximab First-line Metastatic colorectal cancer Colorectal liver metastases Elderly patients

Should capecitabine replace 5-fluorouracil in the first-line treatment of metastatic colorectal cancer?

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World Journal of Gastroenterology 2014年第20期20卷 6092-6101页

作者： Carlos Aguado Beatriz García-Paredes Miguel Jhonatan Sotelo Javier sastre..duardo Díaz-Rubio Department of Medical Oncology Hospital Clínico San Carlos 28040 Madrid Spain

Fluoropyrimidines play a central role in the first-line treatment of metastatic colorectal cancer. Our aim was to review whether capecitabine was a safer, non-inferior, economically superior and more convenient alternative to 5-fluorouracil. Capecitabine has previously been compared to 5-fluorouracil-either as a monotherapy or in combination with oxaliplatin, irinotecan, or biological drugs-and has been found to have comparable efficacy and safety profiles. Furthermore, pharmacoeconomic data and patients’ preferences for oral chemotherapy further favor capecitabine. Therefore, capecitabine appears to be an effective and safe alternative to fluorouracil in the first-line treatment of metastatic colorectal cancer.

关键词： Capecitabine 5-Fluorouracil Metastatic colorectal cancer

Germanium transport across supported liquid membrane with Cyanex 923: Mathematical modeling

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Transactions of Nonferrous Metals Society of China 2019年第9期29卷 1956-1966页

作者： Hossein KAMRAN HAGHIGHI Mehdi IRANNAJAD Ana MARIA sastre Department of Mining and Metallurgical Engineering Amirkabir University of TechnologyTehranIran Department of Chemical Engineering Universitat Politècnica de CatalunyaESTEIBAv.Diagonal 64708028 BarcelonaSpain

A mathematical model was developed to monitor the facilitated transport of germanium(IV) from oxalic acid solutions through a flat sheet supported liquid membrane(FSSLM) containing four trialkylphosphine oxides(Cyanex 923). The FSSLM modeling was based on the extraction constant(Kext) calculated from the liquid-liquid extraction(LLX) modeling. The LLX model presented a reliable calculation of the extraction constant(Kex= 2.057×103 L/mol4). The FSSLM model was solved using Matlab■ software according to extraction constant, Fick’s law, and diffusional principles. The model predicts the overall mass transfer coefficient(Korg) to be 3.84 cm/s. Using this value, diffusion coefficients(Dm) for various Cyanex 923 concentrations of 0.126, 0.252, 0.378, 0.505, 0.631 and 0.757 mol/L are found to be 8.50×10^-4, 4.30×10^-4, 1.87×10^-4, 5.87×10^-5, 2.57×10^-5, 2.09×10^-5 cm2/s, respectively. The results show that the diffusion rate of the current study is approximately more than that of similar FSSLM systems containing Cyanex 923 used to transport various metals. The modeling values are in good agreement with the experimental data, showing the good reliability of the mathematical model.

关键词： supported liquid membrane Cyanex 923 germanium transport mathematical modeling