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Determination of the Apparent Gas Permeability in a Macrocracked Concrete

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Engineering 2022年第10期17卷 93-98页

作者： Pierre rossi Univ Gustave Eiffel French Institute of Science and Technology for TransportDevelopment and Networks(IFSTTAR)Marne-la-Vallée F-77447France

This paper reports on analysis of an expermental study that armed to determine the apparent gas permeability in cracked *** is a lack of research on this topic in the international literature,due to the difficulty of performing reliable experimental testing for gas *** principal interest of this work is to present new and reliable experimental *** functions between the evolution of the apparent crack permeability and the apparent crack opening are also *** functions appear to be relevant in consideration of Poiseuille theory.

关键词： Concrete Macrocrack Gas transfer Permeability

Efficient Gaussian process regression for prediction of molecular crystals harmonic free energies

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npj Computational Materials 2021年第1期7卷 1552-1561页

作者： Marcin Krynski Mariana rossi Fritz Haber Institute of the Max Planck Society Faradayweg 4-614195 BerlinGermany Faculty of Physics Warsaw University of TechnologyKoszykowa 7500-662 WarsawPoland MPI for the Structure and Dynamics of Matter Luruper Chaussee 14922765 HamburgGermany

We present a method to accurately predict the Helmholtz harmonic free energies of molecular crystals in high-throughput *** is achieved by devising a computationally efficient framework that employs a Gaussian Process Regression model based on local atomic *** cost to train the model with ab initio potentials is reduced by starting the optimization of the framework parameters,as well as the training and validation sets,with an empirical *** is then transferred to train the model based on density-functional theory potentials,including *** benchmarked our framework on a set of 444 hydrocarbon crystal structures,comprising 38 polymorphs and 406 crystal structures either measured in different conditions or derived from these *** performance and high prediction accuracy,with mean absolute deviation below 0.04 kJ mol^(−1) per atom at 300 K is achieved by training on as little as 60 crystal ***,we demonstrate the predictive efficiency and accuracy of the developed framework by successfully calculating the thermal lattice expansion of aromatic hydrocarbon crystals within the quasi-harmonic approximation,and predict how lattice expansion affects the polymorph stability ranking.

关键词： harmonic crystal Gaussian

A natural neighbour method based on Fraeijs de Veubeke variational principle for materially non-linear problems

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Acta Mechanica Sinica 2009年第1期25卷 83-93页

作者： Xiang Li Serge Cescotto Barbara rossi Dalian University of Technology 116023 Dalian China ArGEnCo Department University of Liege Liege Belgium

The natural neighbour method can be considered as one of many variants of the meshless methods. In the present paper, a new approach based on the Fraeijs de Veubeke （FdV） functional, which is initially developed for linear elasticity, is extended to the case of geometrically linear but materially non-linear solids. The new approach provides an original treatment to two classical problems： the numerical evaluation of the integrals over the domain A and the enforcement of boundary conditions of the type ui = hi on Su. In the absence of body forces （Fi = 0）, it will be shown that the calculation of integrals of the type fA .dA can be avoided and that boundary conditions of the type ui = hi on Su can be imposed in the average sense in general and exactly if hi is linear between two contour nodes, which is obviously the case for tTi = O.

关键词： Natural neighbour method Meshless methodFraeijs de Veubeke variational principle Discretization Voronoi cell

Mitochondrial bioenergetics and neurodegeneration:a paso doble

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Neural Regeneration Research 2021年第4期16卷 686-687页

作者： Alice rossi Paola Pizzo Department of Biomedical Sciences University of PaduaPaduaItaly Department of Neuroscience Max-Delbruck Centrum fur Molekulare MedizinBerlinGermany

Mitochondria and neuronal activity:The brain is one of the highest energy demanding organs,consuming~20%of the total ATP produced by the whole ***,neurons mainly rely on ATP synthesized by mitochondrial bioenergetics and neuronal activity is strictly dependent on specific mitochondrial localization at synapses,sites consuming a high amount of energy requested for both pre-and post-synaptic ***,mitochondria produce ATP and buffer Ca^2+rises,two essential processes for neurotransmission and generation of membrane potential along the axon(Magistretti and Allaman,2015).

关键词： organs consuming energetics

Mapping and ultrastructure of antennal chemosensilla of the wheat bug Eurygaster maura

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Insect Science 2009年第2期16卷 193-203页

作者： Roberto Romani Marco Valerio rossi Stacconi Dipartimento di Scienze Agrarie e Ambientali Facolt& di Agraria Universit& degli Studi di Perugia Perugia Italy

Antennae of the wheat stink bug Eurygaster maura L. （Hemiptera： Scutelleridae） were investigated to elucidate structure and distribution of antennal chemosensilla in females. Five type of sensilla were identified and characterized using a scanning electron microscope （SEM） and a transmission electron microscope （TEM）. Type 1 sensilla are mechanical and contact chemoreceptors with a single apical pore. Types 2 and 3 sensilla are multiporous chemoreceptors both with typical features of olfactory sensilla. Type 4 are multiporous peg-like sensilla, short and with a grooved surface. Type 5 are sensilla coeloconica with a smooth and aporous peg completely inserted in a sub-cuticular chamber. All types are distributed on the two flagellar segments, but we considered only the apical flagellomere in which the largest number of sensilla are located. The most abundant sensilla are type 3, while the less numerous are type 5. All types, except type 2, decreased in number from the tip to the base of the segment. The lower density of sensilla was recorded on the dorsal-internal part of the apical antennomere, while the higher density was recorded on the opposite side （external-ventral）.

关键词： functional anatomy gustatory sensilla Hemiptera olfactory sensilla thermo-hygro receptors

Geology of Mars after the first 40 years of exploration

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Research in Astronomy and Astrophysics 2010年第7期10卷 621-652页

作者： Angelo Pio rossi Stephan van Gasselt International Space Science Institute CH-3012 Hallerstrasse 6 Bern Switzerland Jacobs University Bremen Department of Earth and Space Sciences Campus Ring 1 28759 Bremen Germany Planetary Sciences and Remote Sensing Institute of Geological Sciences Free University of Berlin Malteserstr. 74-100 12249 Berlin Germany

The knowledge of Martian geology has increased enormously in the last 40 yr. Several missions orbiting or roving Mars have revolutionized our understanding of its evolution and geological features, which in several ways are similar to Earth, but are extremely different in many respects. The impressive dichotomy between the two Martian hemispheres is most likely linked to its impact cratering history, rather than internal dynamics such as on Earth. Mars＇ volcanism has been extensive, very longlived and rather constant in its setting. Water was available in large quantities in the distant past of Mars, when a magnetic field and more vigorous tectonics were active. Exogenic forces have been shaping Martian landscapes and have led to a plethora of landscapes shaped by wind, water and ice. Mars＇ dynamical behavior continues, with its climatic variation affecting climate and geology until very recent times. This paper tries to summarize major highlights in Mars＇ Geology, and points to deeper and more extensive sources of important scientific contributions and future exploration.

关键词： planets and satellites Mars -- Geology -- surface processes -- interior processes

Analysis of suitable geometrical parameters for designing a tendon-driven under-actuated mechanical finger

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Frontiers of Mechanical Engineering 2016年第2期11卷 184-194页

作者： Francesco PENTA Cesare rossi Sergio SAVINO Department of Industrial Engineering University of Naples 'FedericoII' Naples 80125 Italy

This study aims to optimize the geometrical parameters of an under-actuated mechanical finger by conducting a theoretical analysis of these parameters. The finger is actuated by a flexion tendon and an extension tendon. The considered parameters are the tendon guide positions with respect to the hinges. By applying such an optimization, the correct kinematical and dynamical behavior of the closing cycle of the finger can be obtained. The results of this study are useful for avoiding the snap- through and the single joint hyperflexion, which are the two breakdowns most frequently observed during experi- mentation on prototypes. Diagrams are established to identify the optimum values for the tendon guides position of a finger with specified dimensions. The findings of this study can serve as guide for future finger design.

关键词： tendon-driven fingers mechanical fingerdesign under-actuated mechanical systems

RIGOROUS ESTIMATES ON BALANCE LAWS IN BOUNDED DOMAINS

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Acta Mathematica Scientia 2015年第4期35卷 906-944页

作者： Rinaldo M.COLOMBO Elena rossi Unità INdA M Università di Brescia Dipartimento di Matematica ed Applicazioni Università di Milano-Bicocca

The initial-boundary value problem for a general balance law in a bounded domain is proved to be well posed. Indeed, we show the existence of an entropy solution, its uniqueness and its Lipschitz continuity as a function of time, of the initial datum and of the boundary datum. The proof follows the general lines in [4], striving to provide a rigorous treatment and detailed references.

关键词： balance laws initial-boundary value problem for balance laws

Windmills： Ancestors of the wind power generation

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Frontiers of Mechanical Engineering 2017年第3期12卷 389-396页

作者： Cesare rossi Flavio RUSSO Sergio SAVINO Department of Industrial Engineering University of Naples "Federico Ⅱ" via Claudio Naples 80125 Italy Consultant of Ufficio Storico Stato Maggiore Esercito Torre Del Greco 80059 Italy

A brief description of the windmills from the second millennium BC to the Renaissance is presented. This survey is a part of several studies conducted by the authors on technology in the ancient world. The windmills are the first motor, other than human muscles, and are the ancestors of the modem wind turbines. Some authors＇ virtual reconstructions of old windmills are also presented. The paper shows that the operating principle of many modem machines had already been conceived in the ancient times by using a technology that was more advanced than expected, but with two main differences, as follows： Similar tasks were accomplished by using much less energy; and the environmental impact was nil or very low. Modem designers should sometimes consider simplicity rather than the use of a large amount of energy.

关键词： windmills ancient machines history of windmill