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The Superconductivity in Fe-Based Family of Superconductors and Its Electronic Structure Analysis in Presence of Dopants Rh and Pd

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Journal of Quantum Information Science 2022年第4期12卷 111-124页

作者： Ronald Columbié-Leyva Alberto López-vivas[1† ] Ulises Miranda Ilya G. Kaplan Instituto de Investigación en Materiales UNAM CDMX México Baltic Scientific Instruments Riga Latvia

The discovered in 2008 Fe-based superconductors (SC) are a paramagnetic semimetal at ambient temperature and in some cases they become superconductor upon doping. In spite of so many years since its discovery it is still not known the mechanism that leads to superconductivity. The electronic structure study is used for determining key features of the SC mechanism in these materials. The calculations were performed using the modern suite of programs MOLPRO 2021. We performed quantum calculations of a cluster embedded in a background charge distribution that represents the infinite crystal. The Natural Population Analysis was used for determining the charge and spin distribution in the studied materials. As follows from our results, the possible mechanism for superconductivity corresponds to the RVB theory proposed by Anderson for high Tc superconductivity in cuprates.

关键词： Iron-Based High-Tc Superconductors Superconductivity Embeded Cluster Method Natural Bonding Orbitals Analysis

A second-order cell-centered Lagrangian scheme for 2D elastic-plastic flows

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A second-order cell-centered Lagrangian scheme for 2D elasti...

Quantum Mechanical Calculations of High-T<sub>c</sub>Fe-Superconductors

中国力学大会-2015

作者：程军波江松 toro EF 北京应用物理与计算数学研究所意大利TRento大学数学系

We introduce a second-order cell-centered Lagrangian scheme for two-dimensional elastic-plastic problems with the hypo-elastic constitutive model and the yon Mises yield *** this paper,we analyze the wave structure of the Riemann problem for elastic-plastic materials and then develop a four-rarefaction-wave Riemann solver with elastic and plastic

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Journal of Quantum Information Science 2021年第2期11卷 84-98页

作者： Ronald Columbié-Leyva Ulises Miranda Alberto López-vivas Jacques Soullard Ilya G. Kaplan Instituto de Investigación en Materiales National Autonomous University of Mexico Ciudad de México México Institute of Atomic Physics and Spectroscopy University of Latvia Riga Latvia Instituto de Física National Autonomous University of Mexico Ciudad de México México

In introduction we presented a short historical survey of the discovery of superconductivity (SC) up to the Fe-based materials that are not superconducting in a pure state. For this type of material, the transition to SC state occurs in presence of different dopants. Recently in the Fe-based materials at high pressures, the SC was obtained at room critical temperature. In this paper, we present the results of calculations of the isolated cluster representing infinitum crystal with Rh and Pd as dopants. All calculations are performed with the suite of programs Gaussian 16. The obtained results are compared with our previous results obtained for embedded cluster using Gaussian 09. In the case of embedded cluster our methodology of the Embedded Cluster Method at the MP2 electron correlation level was applied. In the NBO population analysis two main features are revealed: the independence of charge density transfer from the spin density transfer and, the presence of orbitals with electron density but without spin density. This is similar to the Anderson’s spinless holon and confirms our conclusions in previous publications that the possible mechanism for superconductivity can be the RVB mechanism proposed by Anderson for high Tc superconductivity in cuprates.

关键词： Superconductivity Fe-Based Superconductors Embedded Cluster Method MP2 Method NBO Analysis

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UGC信息类型对用户心流体验的影响

新闻传播 2021年第21期 21-22页

作者： isabela ZHANG 上海交通大学媒体与传播学院上海200240

在这信息爆炸的时代,汹涌而来的信息总是使人不知所措,注意力成了稀缺资源,在信息的浪潮中如何脱颖而出不断吸引用户成了无法逃避的话题。本文从传播学角度选取UGC (User Generated Content,即用户原创内容)信息类型角度,通过实证的方法... 详细信息

在这信息爆炸的时代,汹涌而来的信息总是使人不知所措,注意力成了稀缺资源,在信息的浪潮中如何脱颖而出不断吸引用户成了无法逃避的话题。本文从传播学角度选取UGC (User Generated Content,即用户原创内容)信息类型角度,通过实证的方法,以在校大学生为研究主体,以"UGC用户生成信息类型——心流体验"构建概念模型,以UGC信息类型(情绪型vs.描述型)的组间实验探讨用户原创内容UGC信息类型对用户心流体验的影响。研究结果发现:用户原创内容UGC信息类型对用户心流体验有显著影响,相比描述型信息,情绪型UGC信息对品牌态度的影响更好。

关键词： UGC 信息类型心流体验

UGC用户原创信息类型对品牌态度的影响研究

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新闻传播 2021年第23期 25-26页

作者： isabela ZHANG 上海交通大学媒体与传播学院上海200240

本研究通过实证的方法,以在校大学生为研究主体,以"UGC用户生成信息类型——品牌态度"结合个人卷入度作为调节变量的框架,构建概念模型,探讨了UGC用户生成信息类型对品牌态度的影响以及在个人卷入度的调节下,UGC用户生成信息类型是否会... 详细信息

本研究通过实证的方法,以在校大学生为研究主体,以"UGC用户生成信息类型——品牌态度"结合个人卷入度作为调节变量的框架,构建概念模型,探讨了UGC用户生成信息类型对品牌态度的影响以及在个人卷入度的调节下,UGC用户生成信息类型是否会影响品牌态度。研究结果发现:用户原创内容UGC信息类型对品牌态度有显著影响,相比图片+文字,视频型UGC信息对品牌态度的影响更好;同时,个人卷入度对UGC信息类型于品牌态度有调节效果。

关键词：用户原创UGC信息信息类型品牌态度个人卷入度

Production and Nutritional Quality of Tomatoes(Solanum lycopersicum ***)Are Improved in the Presence of Biochar and Inoculation with Arbuscular Mycorrhizae

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American Journal of Plant Sciences 2020年第3期11卷 426-436页

作者： Wilson Castaneda Marcia toro Andi Solorzano Doris Zúniga-Dávila Laboratorio de Ecologia Microbiana y Biotecnologia Departamento de BiologiaFacultad de CienciasUniversidad Nacional Agraria La MolinaLimaPeru

Tomato is a fruit of great nutritional interest in the basic human diet. The increasing use of agrochemicals to maintain production requires new alternatives to reduce environmental impact. Arbuscular mycorrhizae (AM) are beneficial microorganisms that favor the growth of plants improving their nutrition and development, protecting the plant from biotic and abiotic stresses and favoring the production of bioactive compounds that increase their nutritional value. The use of biochar as soil conditioner is also considered an environmentally friendly resource. A greenhouse experiment was carried out to observe the effect of the use of biochar and AM inoculation on the quality of fruits, yield and polyphenols production of Cherry tomato, Solanum lycopersicum var. Cerasiforme. A mixture of rice husk biochar with sterile sand and two inoculums of Glomeromycota native fungi: from a wetland (GWI) and a fallow field (GFI) were used. Control treatments consisted of inoculation with both GWI and GFI in sterile sand. All treatments were irrigated with 50% La Molina? hydroponic solution. After 12 weeks plants were harvested to quantify weight, number and diameters of the fruits, and yield, total polyphenols in the fruit pulp were quantified. In the presence of biochar and the two inoculums, GFI and GWI, fruit production was favored throughout the experiment. The height of the plants was significantly greater in the presence of biochar. Plants grown in biochar and inoculated with GFI had a yield of 8.2 MT/Ha, increasing in 50% this value respect to control with biochar (5.33 MT/Ha). This treatment doubled the number of fruits (59.5) with respect to the control (32.5). Root colonization by GFI was not affected by the presence of biochar. It is concluded that the combined use of rice husk biochar and Glomeromycota fungal inoculation is recommended for increasing of Cherry tomato yield and improving fruit quality through the production of bioactive compounds.

关键词： Glomeromycota Fungi Yield Polyphenols

Effect of Heavy Metals on the Growth of Bacteria Isolated from Sewage Sludge Compost Tea

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Advances in Microbiology 2014年第10期4卷 644-655页

作者： María Vela-Cano Antonio Castellano-Hinojosa Antonia Fernández vivas María Victoria Martínez Toledo Department of Microbiology University of Granada Campus de Fuentenueva s/n Granada Spain Institute of Water Research University of Granada Granada Spain

The amount of urban sewage sludge is increasing daily. For this reason, it is necessary to have an environmentally friendly use for this residue. Land applications in olive grove soil, poor quality soil, as a compost or a compost tea could be considered as one of the best options, because it has a high content of organic matter. However, the presence of heavy metals in some sewage sludge could be an environmental problem. In this sense, the aim of this work is to check the tolerance of the culturable microbiota present in sewage sludge compost tea to four heavy metals, Cu, Cd, Pb and Zn. Among microbiota isolated, eight strains showed high resistance to Pb, Zn, Cu and Cd, and one microbe (Rhodococcus sp.) showed a special tolerance to every heavy metal. The strains were divided into six genrera: Rhodococcus, Virgibacillus, Leifsoni, Achromobacter, Cupriavidus and Oceanobacillus sp. Finally, Rhodococcus sp. strain 3 was able to remove different amounts of heavy metals from the culture media with intracellular and surface accumulation of Cu, Zn, Pb and Cd. The application of this bacterial strain in bioremediation processes is discussed.

关键词： Wastewater Sludge Compost Tea Minimum Inhibitory Concentration Heavy-Metal Removal Rhodococcus sp.

Hybrid heuristic and mathematical programming in oil pipelines networks: Use of immigrants

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2005年第1期6卷 9-19页

作者： DE LA CRUZ J.M HERRáN-GONZáLEZ A RISCO-MARTíN J.L ANDRéS-toro B Department of Computer Architecture and Automatic Control Complutense University of Madrid 28040 Madrid SpainDepartment of Computer Architecture and Automatic Control Complutense University of Madrid 28040 Madrid SpainDepartment of Computer Science Engineering C.E.S. Felipe II (U.C.M.) 28300 Aranjuez SpainDepartment of Computer Architecture and Automatic Control Complutense University of Madrid 28040 Madrid Spain

We solve the problem of petroleum products distribution through oil pipelines networks. This problem is modelled and solved using two techniques: A heuristic method like a multiobjective evolutionary algorithm and Mathematical Programming. In the multiobjective evolutionary algorithm, several objective functions are defined to express the goals of the solutions as well as the preferences among them. Some constraints are included as hard objective functions and some are evaluated through a repairing function to avoid infeasible solutions. In the Mathematical Programming approach the multiobjective optimization is solved using the Constraint Method in Mixed Integer Linear Programming. Some constraints of the mathematical model are nonlinear, so they are linearized. The results obtained with both methods for one concrete network are presented. They are compared with a hybrid solution, where we use the results obtained by Mathematical Programming as the seed of the evolutionary algorithm.

关键词： MOEA MILP Hybrid algorithm Constraints

Knowledge arising from long-term research of variable retention harvesting in Tierra del Fuego: where do we go from here?

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Ecological Processes 2019年第1期8卷 318-333页

作者： Guillermo J.Martínez Pastur Yamina M.Rosas Mónica toro Manríquez Alejandro Huertas Herrera Juan A.Miller Juan M.Cellini Marcelo D.Barrera Pablo L.Peri María V.Lencinas Centro Austral de Investigaciones Científicas(CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Houssay 200(9410)UshuaiaTierra del FuegoArgentina Universidad Nacional de la Plata(UNLP) Calle 7 e/47 y 48(1900)La PlataBuenos AiresArgentina Instituto Nacional de Tecnología Agropecuaria(INTA) Universidad Nacional de la Patagonia Austral(UNPA)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)cc 332(9400)Río GallegosSanta CruzArgentina

Nothofagus pumilio forests in Tierra del Fuego are the southernmost forests in the world,where extreme climate conditions represent a challenge to attain sustainable forest *** forestry was proposed as an alternative to increase the species conservation in managed ***,we synthetized results related to the implementation of a variable retention harvesting based on a combination of aggregate patches and dispersed retention during the last 18 years comparing with other silviculture proposals(e.g.,shelterwood cuts)and control treatments(primary unmanaged forests).We summarized the results for(i)sawmill operations,(ii)timber yield,(iii)overstory stability,(iv)forest structure,(v)microclimate and natural cycles,(vi)natural regeneration dynamics(flowering,seeding,foraging,recruitment,growth,and mortality),and(vii)biodiversity(mammals,understory plants,mistletoes,birds,arthropods,mosses,lichens,and fungi).In general,aggregate patches maintained forest structure and micro-environmental variables,and slightly increased biodiversity and forest reproduction variables compared to unmanaged primary *** the contrary,dispersed retention decreased forest structure variables and greatly increased biodiversity(richness and abundance)when it was compared to unmanaged primary *** conditions are influenced by variable retention harvesting,but direction and magnitude of the effect depend and differ according to retention *** this,biodiversity taxa greatly differed among groups depending on retention *** general,the species assemblages in aggregate patches were similar to those found in primary unmanaged forests,while they were significantly modified in the dispersed *** occurred due to(i)local extinction of some original species,(ii)the introduction of native species from the surrounding environments,or(iii)the invasion of exotic *** silvicultural method has been a useful tool to conserve biodiversity and ec

关键词： Aggregate patches Dispersed retention Biodiversity conservation Long-term sustainability Timber production