Articles de revues : « Porou »

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Robertson, Natalie. « Swirling currents emerge at the Waiapu river mouth : Lens-based witnessing, documenting and storytelling of slow catastrophes ». Journal of Environmental Media 2, n^o 1 (1 novembre 2021) : 6.1–6.16. http://dx.doi.org/10.1386/jem_00054_1.

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This article considers how Indigenous stories and chants can tell us about our ecologies in the time of environmental emergencies. For Ngāti Porou of the lower reaches of the Waiapu river catchment in Te Ika-a-Māui, the North Island of Aotearoa (New Zealand), the slow catastrophes of twentieth-century colonial deforestation impacts, introduced pest-induced inland forest collapse and predicted twenty-first-century climate change sea level rise have converged as our most pressing environmental problems. Waiapu is home to Ngāti Porou Tūturu, coastal fishing people who value their relationships with fish species, notably kahawai. The mōteatea chant form acts as a guide to my photographic and moving image practice to visualize and voice the slow catastrophe of the river. In this article, I discuss how the Ngāti Porou mōteatea He Tangi mo Pāhoe, which reveals nineteenth-century ecological knowledge, particularly of fish species, is reimagined as a moving image visual mōteatea. Through reframing the threats as the current faces of our ancestors, this article proposes a shift in thinking from vulnerability into resilience.

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Brewin, Marilyn, et Carolyn Coggan. « Evaluation of the Ngati Porou community injury prevention project ». Ethnicity & ; Health 9, n^o 1 (février 2004) : 5–15. http://dx.doi.org/10.1080/1355785042000202754.

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Rasulov, A., et U. Dalabaev. « Flow in a channel with porous insert ». IOP Conference Series : Earth and Environmental Science 990, n^o 1 (1 février 2022) : 012027. http://dx.doi.org/10.1088/1755-1315/990/1/012027.

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Abstract Filtration of an incompressible liquid (gas) in a non-deformable porou s medium is investigated. The results of numerical simulation of the hydrodynamic features of the flow arising after the passage of the liquid through a layer of an immobile porous medium are presented. An interpenetrating model of multiphase media is used to describe such flows. The porosity and permeability of the porous medium, as well as the force of interfacial interaction, are considered in the framework of compliance with the Kozeny-Karman ratio. The influence of the geometrical shape of the bulk layer on the nature and magnitude of the inhomogeneity of the flow velocity behind the obstacle is shown. Considering the shape of the porous medium significantly affects the flow parameters. Numerical simulation results are compared with experimental data. The effects of the non-uniformity of the fluid velocity field arising from the curvature of the layer surface and the influence of the arising inhomogeneity on the velocity are investigated by the methods of a computational experiment. A qualitative comparison is made of velocity inhomogeneities when a fluid flows through a porous obstacle. For the numerical implementation of the filtration equation of the interpenetrating model, a SIMPLElike algorithm was used.

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Defngin, Axel. « A Whakapapa of Tradition : 100 Years of Ngāti Porou Carving, 1830–1930 by Ngarino Ellis ». Contemporary Pacific 34, n^o 1 (2022) : 236–38. http://dx.doi.org/10.1353/cp.2022.0018.

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Robertson, Natalie. « Roimata Toroa ». Pacific Journalism Monographs : Te Koakoa : Ngā Rangahau, n^o 7 (30 novembre 2017) : 8–9. http://dx.doi.org/10.24135/pjm.v0i7.16.

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I n Te Ao Mãori, the Toroa (albatross) is sacred. Roimata Toroa, albatross tears, is a widely used tukutuku pattern. Derived from the Te Tairawhiti Ngati Porou story of Pourangahua, the pattern speaks of themisadventures of travelers who take shortcuts in haste to get to port. Pourangahua was an agriculturist who traveling a return journey to Aotearoa to grow kumara, gifted to him by Ruakapenga, a tohunga and learned scientist. Lent two pet albatrosses, Harongarangi and Tiungarangi, by Ruakapenga, Pourangahua is given strict instructions on which hazards to avoid, the care of the birds, and a karakia to give thanksgiving for their safe return. In his hurriedness to see his wife Kaniowai, Pourangahua takes a shortcut, runs into a taniwha (a denotation of hazards), and forgets the karakia and fails to care for the birds,leading to their grief and eventual demise. Realising he has dishonoured Ruakapenga, Pourangahua tries to cover his mistake, by belatedly doing the karakia, but it is too late. The damage was done...

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Puke, Wiremu T. « Conception, construction and the cultural significance of Te Parapara Garden in Hamilton, Aotearoa New Zealand ». Journal of New Zealand & ; Pacific Studies 9, n^o 2 (1 décembre 2021) : 179–98. http://dx.doi.org/10.1386/nzps_00071_1.

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Te Parapara Garden is the only complete pre-European-style Māori horticultural garden in the world. Historically inspired and empirically researched, it lies within the Hamilton Gardens on a young river terrace immediately adjacent to the Waikato River in Hamilton (Kirikiriroa), Aotearoa New Zealand. In this article, Wiremu Puke (Ngāti Wairere, Ngāti Porou) ‐ a tohunga whakairo (master carver, including using pre-steel tools) and a tohunga whakapapa (genealogical expert on his tribal affiliations) of Ngāti Wairere (the mana whenua, or first people of the traditional ancestral tribal lands of Kirikiriroa) ‐ describes the design and development of Te Parapara Garden from its initial concept in 2003 and the construction of its many features, including the waharoa (gateway), pou (carved pillars), pātaka (storehouse), whatarangi (small storehouse), taeapa (fencing) and rua kūmara (underground storage pit), and the sourcing and use of kōkōwai (red ochre). The garden was completed in 2010. Its ongoing functioning, including the annual planting and harvesting of traditional pre-European kūmara (sweet potato) using modified, mounded soils (puke or ahu), is also covered. The unique Te Parapara Garden is of great cultural importance and a source of pride, knowledge and understanding for national and international visitors and empirical and academic researchers.

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Kojola, Ilpo, Timo Helle et Pekka Aikio. « Productivity of semi-domesticated reindeer in Finland ». Rangifer 11, n^o 2 (1 octobre 1991) : 53. http://dx.doi.org/10.7557/2.11.2.978.

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In spite of a twofold increase in the density of reindeer in Finland from 1974 to 1987, meat production per reindeer increased during this period. This was possible due to calf harvesting and supplemental feeding. Results from multiple regression models indicated that calf harvesting influenced both per unit area and per capita production more than supplemental feeding. Correlation between meat production and animal density decreased with increased supplemental feeding. Traditionally, southern and central herds of reindeer fed mainly on arboreal lichens in late winter; however, due to large-scale logging, woodlands rich of arboreal lichens had been greatly reduced. Economic carrying capacity of the winter range apparently has been exceeded in the south; a heavy crash in the number of reindeer is likely if supplemental feeding ceases. In northern herds, intensive calf harvesting enabled satisfactory yield without supplemental feeding. In northern herds, yield increased mainly per unit area (i.e. by increases in herd size); in the south yield per reindeer increased.Lithantuotantoon vaikuttavat tekijat Suomen poron-hoidossa.Abstract in Finnish / Tiivistelmd: Huolimatta Suomessa vuosien 1974 ja 1987 valilla tapahtuneesta porotiheyden kaksinkertaistumisesta, lihantuotto poroa kohti kasvoi jakson aikana. Tama johtui oletettavasti vasateurastuksesta ja lisaruokinnasta. Monimu-uttujaregressiomallien tulosten perusteella vasateurastuksella nayttaisi olevan lisaruokintaa suurempi vaikutus seka poroa etta pinta-alaa kohti laskettuun tuottoon. Ruokinnan tehostuessa pienentyi lihantuoton ja porotiheyden valinen riippuvuus. Etelaosan ja keskiosan porot syovat perinteisesti puussa kasvavia jakalia kevattalvella. Hakkuista johtuen luppometsien osuus on suuresti vahentynyt. Talvilaidunten ekonomien kantokyky on ilmeisesti ylitetty etela- ja keski-osassa; syva romahdus poromaarissa on todennakoista, jos ruokinta lopetettaisiin. Pohjoisosassa voima-perainen vasate-urastus mahdollistaa tyydyttavan tuoton ilman ruokintaa. Pohjoisessa tuotto kasvoi pinta-alayksikkoa kohden (poro-maarat kasvoivat), etelassa kasvoi poroa kohti laskettu tuotto.

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Tsai, Yu-Chih, Jechan Lee, Eilhann Kwon, Chao-Wei Huang, Nguyen Nhat Huy, Siming You, Pei-Syuan Hsu, Wen Da Oh et Kun-Yi Andrew Lin. « Enhanced Catalytic Soot Oxidation by Ce-Based MOF-Derived Ceria Nano-Bar with Promoted Oxygen Vacancy ». Catalysts 11, n^o 9 (18 septembre 2021) : 1128. http://dx.doi.org/10.3390/catal11091128.

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As CeO2 is a useful catalyst for soot elimination, it is important to develop CeO2 with higher contact areas, and reactivities for efficient soot oxidation and catalytic soot oxidation are basically controlled by structures and surface properties of catalysts. Herein, a Ce-Metal organic framework (MOFs) consisting of Ce and benzene-1,3,5-tricarboxylic acid (H3BTC) is employed as the precursor as CeBTC exhibits a unique bar-like high-aspect-ratio morphology, which is then transformed into CeO2 with a nanoscale bar-like configuration. More importantly, this CeO2 nanobar (CeONB) possesses porou, and even hollow structures, as well as more oxygen vacancies, enabling CeONB to become a promising catalyst for soot oxidation. Thus, CeONB shows a much higher catalytic activity than commercial CeO2 nanoparticle (comCeO) for soot oxidation with a significantly lower ignition temperature (Tig). Moreover, while soot oxidation by comCeO leads to production of CO together with CO2, CeONB can completely convert soot to CO2. The tight contact mode also enables CeONB to exhibit a very low Tig of 310 °C, whereas the existence of NO also enhances the soot oxidation by CeONB to reduce the Tig. The mechanism of NO-assisted soot oxidation is also examined, and validated by DRIFTS to identify the formation and transformation of nitrogen-containing intermediates. CeONB is also recyclable over many consecutive cycles and maintained its high catalytic activity for soot oxidation. These results demonstrate that CeONB is a promising and easily prepared high-aspect-ratio Ce-based catalyst for soot oxidation.

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Babu, Lenin, et Chandramouli Padmanabhan. « Hybrid Active and Passive Noise Control of Cavities ». Acta Acustica united with Acustica 97, n^o 5 (1 septembre 2011) : 752–60. http://dx.doi.org/10.3813/aaa.918455.

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In this paper a hybrid active noise control of a cavity with poro-elastic material has been investigated. It has been found that the noise reduction achieved with active noise control in the cavity without poro-elastic material is not significantly altered with the presence of poro-elastic materials. This is shown to be independent of the porous material and its thickness and is true both at lower and mid-frequency ranges. Further, it is seen that macro perforations do not alter the sound absorption performance of the poro-elastic material in the presence of active noise control. The results clearly indicate that one can choose a smaller thickness of the porous material when active noise control is used in a cavity for noise suppression.

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Pösö, A. Reeta. « Seasonal changes in reindeer physiology ». Rangifer 25, n^o 1 (1 avril 2005) : 31–38. http://dx.doi.org/10.7557/2.25.1.335.

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The seasonal changes in the photoperiod, temperature and availability of food need to be converted to hormonal signals in order to induce adaptations in the physiology of the reindeer. The most reliable of the seasonal changes in the environment is the photoperiod, which affects the reindeer physiology through pineal gland and its hormone, melatonin. Usually there are large diurnal changes in the concentration of melatonin, but in the reindeer the daily rhythm disappears during the arctic summer to return again in the autumn. Seasonal changes in melatonin secretion are involved in the regulation of reproduction, the growth of pelage, thermogenesis, body mass and immune function. Melatonin may exert its effects through gene activation, but the mechanisms are not completely understood. Other hormones that show seasonality are thyroid hormones, insulin and leptin. Thus the observed physiological changes are a result of actions of several hormones. Appetite, energy production and thermogenesis are all vital for survival. During winter, when energy balance is negative, the reindeer uses mainly body fat for energy production. The use of fat stores is economical as the rate of lipolysis is controlled and the use of fatty acids in tissues such as muscle decreases. Only in severe starvation the rate of lipolysis increases enough to give rise to accumulation of ketone bodies. The protein mass is maintained and only in starved individuals muscle protein is used for energy production. The winter feed of the reindeer, the lichens, is poor in nitrogen and the nitrogen balance during winter is strongly negative. Reindeer responds to limited availability of nitrogen by increasing the recycling of urea into rumen. In general the adaptation of reindeer physiology enables the reindeer to survive the winter and although several aspects are known many others require further studies.Abstract in Finnish / Tiivistelmä: Valaistus, lämpötila ja ravinnon saatavuus vaihtelevat vuodenajn mukaan. Jotta nämä muutokset voisivat saada aikaan adaptiivisia muutoksia porossa, ne täytyy muutta hormonisignaaleiksi. Luotettavin näistä edellä mainituista ympäristön vuodenaikaismuutoksista on valo, joka vaikuttaa poron elintoimintoihin käpylisäkkeen ja sen erittämän hormonin, melatoniinin, välityksellä. Melatoniinin plasmapitoisuuksissa on havaittavissa selkeä vuorokausirytmi, joka porolla häviää kesällä ja alkaa uudestaan syksyllä. Melatoniini-hormonin vuodenaikaisvaihtelut ovat mukana säätelemässä lisääntymistä, talvikarvan kasvua, lämmöntuottoa, elopainoa ja immuunitoimintoja. Melatoniini vaikuttaa geeniaktivaation kautta mekanismeilla, joita ei vielä tarkkaan tunneta. Muita hormoneja, joiden erityksessä on havaittu vuodenaikaisvaihtelua, ovat kilpirauhashormonit, insuliini ja leptiini. Havaitut muutokset ovat ilmeisesti usean hormonin yhteisvaikutuksen aiheuttamia. Ruokahalu sekä energian- että lämmöntuotto ovat keskeisiä hengissä säilymisen kannalta. Talvella poron energiatase on negatiivinen ja se käyttää lähinnä varastoimiaan rasvoja energian tuottoon. Rasvojen käyttö on ekonomista, sillä rasvojen hajoaminen, lipolyysi, on säädeltyä ja rasvahappojen käyttö lihaksissa vähenee talvella. Vasta vakavasti nälkiintyneissä poroissa lipolyysi aktivoituu siten, että myös ketoaineita alkaa kertyä vereen. Valkuaisaineiden määrä vähenee vähemmän kuin rasvojen ja ainoastaan nälkiintyneet porot käyttävät lihasten valkuaisaineita energiantuottoon. Poron talviravinnossa, jäkälässä, on vain vähän typpeä, joten talvisin typpitasapaino on voimakkaasti negatiivinen. Poro reagoi tähän vähäiseen typpimäärään lisäämällä urean kierrätystä pötsiin. Kokonaisuudessaan poron elintoimintojen sopeutuminen auttaa poroa selviytymään talven yli. Vaikka adaptaatiosta on joiltakin osin kertynyt runsaasti tietoa, on siinä myös paljon selvitettävää.

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Costa, Eliane Betânia Carvalho, Fernando Akira Kurokawa et Vanderley Moacyr John. « Modelagem simplificada para estimativa do potencial de penetração de partículas em substratos porosos ». Ambiente Construído 13, n^o 1 (mars 2013) : 25–34. http://dx.doi.org/10.1590/s1678-86212013000100003.

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Um modelo simplificado foi desenvolvido para estimar o potencial de penetração de partículas típicas de matrizes de argamassas e concretos nos poros de um substrato. O modelo considera que, após serem lançadas sobre a superfície, as partículas com área de projeção no plano menor ou igual à área do poro podem penetrá-la. Foram estudadas cinco matrizes distintas, constituídas por partículas de cimento, cal, filer calcário, microssílica e argamassa aplicadas em três substratos com distribuição do tamanho de poros similares aos encontrados no mercado nacional. A distribuição granulométrica das partículas foi obtida por ensaios de granulometria a laser e a distribuição do tamanho dos poros e a porosidade dos substratos por porosimetria de intrusão de mercúrio. Os resultados obtidos mostraram que o potencial penetração de partículas nos poros não atinge 1% do volume total de partículas presentes na matriz, mesmo para a matriz com granulometria mais fina (microssílica) em substrato com faixa de poros mais ampla (substrato cimentício) numa relação área do poro/área da partícula igual a 1. Conforme modelo proposto, a contribuição da parcela mecânica pela penetração de partículas nos poros para aderência é insignificante.

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Selvadurai, A. P. S., et A. P. Suvorov. « Boundary heating of poro-elastic and poro-elasto-plastic spheres ». Proceedings of the Royal Society A : Mathematical, Physical and Engineering Sciences 468, n^o 2145 (10 mai 2012) : 2779–806. http://dx.doi.org/10.1098/rspa.2012.0035.

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This paper examines the coupled hydro-thermo-mechanical behaviour of a fluid-saturated porous sphere with a skeletal fabric that can exhibit either elastic or elasto-plastic mechanical behaviour. Analytical results for the thermo-poro-elastic response of the sphere subjected to transient heat transfer are complemented by computational results for the analogous thermo-poro-elasto-plastic problem. The results presented in the paper examine the influence of the permeability, thermal expansion properties of the pore fluid and the skeleton, and the elasto-plasticity effects of the porous skeleton on the time-dependent pore fluid pressure, displacement and stress within the sphere.

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Ha, Jonghyun, et Ho-Young Kim. « Capillarity in Soft Porous Solids ». Annual Review of Fluid Mechanics 52, n^o 1 (5 janvier 2020) : 263–84. http://dx.doi.org/10.1146/annurev-fluid-010518-040419.

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Soft porous solids can change their shapes by absorbing liquids via capillarity. Such poro-elasto-capillary interactions can be seen in the wrinkling of paper, swelling of cellulose sponges, and morphing of resurrection plants. Here, we introduce physical principles relevant to the phenomena and survey recent advances in the understanding of swelling and shrinkage of bulk soft porous media due to wetting and drying. We then consider various morphing modes of porous sheets, which are induced by localized wetting and swelling of soft porous materials. We focus on physical insights with the aim of triggering novel experimental findings and promoting practical applications.

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Hoerlle, Fernanda Oliveira, Edmilson Helton Rios, William Godoy de Azevedo Lopes da Silva, Elizabeth May Braga Dulley Pontedeiro, Maira da Costa de Oliveira Lima, Patrick William Michael Corbett, José Luis Drummond Alves et Paulo Couto. « NUCLEAR MAGNETIC RESONANCE TO CHARACTERIZE THE PORE SYSTEM OF COQUINAS FROM MORRO DO CHAVES FORMATION, SERGIPE-ALAGOAS BASIN, BRAZIL ». Revista Brasileira de Geofísica 36, n^o 3 (6 septembre 2018) : 1. http://dx.doi.org/10.22564/rbgf.v36i3.1960.

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ABSTRACT. Nuclear magnetic resonance (NMR) is a recognized petrophysical tool in the oil and gas industry to characterize reservoir rocks and fluids. In this study, the pore system of coquinas from a single bed of a quarry in the Morro do Chaves Formation was evaluated. These sedimentary rocks have been considered as a potential analogous to some Brazilian pre-salt reservoir rocks. The objective of this work was to characterize the porous system of coquinas in terms of total porosity and pore size distribution using low-field NMR. Conversion of T2 relaxation times to pore size radii was performed and literature cut-offs were applied for porosity partitioning. Coquinas were classified and ranked according to their percentage of macro, meso and micro porosity. This work verified quantitatively the pore system heterogeneities for the coquina samples and the variation in the layer from which they were extracted. The study provides some clues on lateral porosity and pore size variation in any reservoir for which this unit is an analogue.Keywords: Petrophysics, NMR, Total Porosity, Pore Size Distribution, Porosity Partitioning.RESUMO. Ressonância magnética nuclear (RMN) é uma técnica petrofísica reconhecida na indústria de óleo e gás pela sua capacidade de caracterizar rochas reservatório e seus fluidos saturantes. Neste estudo, foi avaliado o sistema poroso de coquinas pertencentes à uma camada de uma pedreira na Formação Morro do Chaves. Essas rochas sedimentares foram consideradas possíveis análogos de algumas rochas carbonáticas do pré-sal brasileiro. O objetivo do trabalho foi caracterizar o sistema poroso dessas coquinas em termos de porosidade total e distribuição de tamanho de poros utilizando RMN de baixo campo. Realizou-se a conversão dos tempos de relaxação T2 para raios de poro e empregou-se cut-offs da literatura para o particionamento da porosidade. As coquinas foram classificadas e ranqueadas de acordo com a sua porcentagem de macro, meso e micro poros. Verificou-se quantitativamente a heterogeneidade do sistema poroso das coquinas estudadas e a variação da camada sedimentar em que os plugues foram retirados. O estudo fornece informações sobre a variação lateral de porosidade e tamanho de poros para reservatórios que tenham a unidade estudada como análogo.Palavras-chave: Petrofísica, RMN, Porosidade Total, Distribuição do Tamanho de Poros, Particionamento da Porosidade.

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Satcunanathan, Sutharsan, Matthias Meinke et Wolfgang Schröder. « Impact of Porous Media on Boundary Layer Turbulence ». Fluids 7, n^o 4 (13 avril 2022) : 139. http://dx.doi.org/10.3390/fluids7040139.

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The subsonic flows around NACA 0012 aerofoils with a solid, a porous, and a poro-serrated trailing edge (TE) at a Reynolds number of 1 × 106 are investigated by a hybrid Reynolds-averaged Navier–Stokes (RANS)/large-eddy simulation (LES) approach. The porosity is treated by the method-of-volume averaging. In the RANS, a two-equation low Reynolds number k-ε turbulence model is modified to include the porous treatment. Similarly the equations in the LES are extended by the Darcy–Forchheimer model. The simulation is set up with the broadband turbulent boundary layer trailing edge (TBL-TE) noise prediction as a future objective in mind, i.e., the noise sources in the trailing edge region are captured by the LES. To enforce a physically realistic transition from an averaged RANS solution towards a resolved turbulent flow field, at the inflow of the LES coherent structures are generated by means of the reformulated synthetic turbulence generation (RSTG) method. For the poro-serrated TE, turbulence statistics vary in the spanwise direction between the two extremes of a pure solid and a rectangular porous TE, where porosity locally increases the level of turbulence intensity and alters the near wall turbulence anisotropy.

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Chavez Panduro, Elvia Anabela, Thomas Beuvier, Manuel Fernández Martínez, Leila Hassani, Brice Calvignac, Frank Boury et Alain Gibaud. « Small-angle X-ray scattering analysis of porous powders of CaCO3 ». Journal of Applied Crystallography 45, n^o 5 (9 août 2012) : 881–89. http://dx.doi.org/10.1107/s0021889812032219.

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The results of small-angle and ultra-small-angle X-ray scattering on porous CaCO3microparticles of pulverulent vaterite made by a conventional chemical route and by using supercritical CO2are presented. The scattering curves are analysed in the framework of the Guinier–Porod model, which gives the radii of gyration of the scattering objects and their fractal dimension. In addition, the porosity and the specific surface area are determined by using the Porod invariant, which is modified to take into account the effective thickness of the pellet. The results of this analysis are compared with those obtained by nitrogen adsorption.

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Hung, Tu-Chieh, Yu-Xian Huang et Wei-Mon Yan. « Design of Porous-Microchannel Heat Sinks with Different Porous Configurations ». International Journal of Materials, Mechanics and Manufacturing 4, n^o 2 (2015) : 89–94. http://dx.doi.org/10.7763/ijmmm.2016.v4.231.

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Selvadurai, A. P. S., et A. P. Suvorov. « On the development of instabilities in an annulus and a shell composed of a poro-hyperelastic material ». Proceedings of the Royal Society A : Mathematical, Physical and Engineering Sciences 474, n^o 2218 (octobre 2018) : 20180239. http://dx.doi.org/10.1098/rspa.2018.0239.

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The paper investigates the development of instability in an internally pressurized annulus of a poro-hyperelastic material. The theory of poro-hyperelasticity is proposed as an approach for modelling the mechanical behaviour of highly deformable elastic materials, the pore space of which is saturated with a fluid. The consideration of coupling between the mechanical response of the hyperelastic porous skeleton and the pore fluid is important when applying the developments to soft tissues encountered in biomechanical applications. The paper examines the development of an instability in a poro-hyperelastic annulus subjected to internal pressure. Using a computational approach, numerical solutions are obtained for the internal pressures that promote either short-term or long-term instability in a poro-hyperelastic annulus and a poro-hyperelastic shell. In addition, time-dependent effects of stability loss are examined. The analytical solutions are used to benchmark the accuracy of the computational approach.

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Nieminen, Mauri. « Ennen poro ruokki poromiehen, nyt poromies ruokkii poron ». Suomen Maataloustieteellisen Seuran Tiedote, n^o 33 (31 janvier 2016) : 1–7. http://dx.doi.org/10.33354/smst.75214.

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Suomessa poronomistajia on enää 4 000 ja alle 900 pitää porotaloutta elinkeinonaan. Ylä-Lapin kankailla jäkälämäärä pieneni 30 vuodessa 75 %, ja sitä on enää 120 kg kuivapainoa/ha. Poronhoitoalueen keski ja eteläosassa jäkälää on vain 35 kg/ha. Määrät ovat 10-100 kertaa pienemmät kuin metsäpeuroilla Kuhmossa sekä tunturipeuroilla ja poroilla Etelä-Norjassa ja Kuolassa. Vaikka tunturialueesta on suojeltu yli 80 %, myös tunturikoivikot ovat ylilaidunnettuja ja uhanalaisia. Poroja ruokitaan talvisin kaikissa paliskunnissa ja yli 45 miljoonalla rehukilolla. Rehuista yli puolet on kaupallisia, ja säilörehua tuodaan myös poron oitoalueen ulkopuolelta. Tällä rehumäärällä Suomen noin 200 000 eloporoa elää yli neljä kuukautta. Laitumiltaan kaksi kertaa suuremman Sallan paliskunnan poronhoito poikkeaa suuresti samassa kunnassa sijaitsevasta Pohjois-Sallasta. Kesälaitumia on kolme kertaa enemmän mutta jäkälää erittäin vähän. Eloporotiheys on siellä kaksi kertaa pienempi kuin Pohjois-Sallassa mutta talviruokinta on yleistä. Ruokintakulut olivat tutkimusvuosina 2005-13 Sallassa noin kuusi kertaa suuremmat kuin Pohjois-Sallassa, jossa poroja on ruokittu vähän vain paliskunnan eteläosassa. Sallassa poroelinkeinon tulos ilman peto ja liikennevahinkokorvauksia sekä maataloustukia oli suurista ruokintakuluista johtuen negatiivinen, keskimäärin jopa 6 000 euroa/poronomistaja. Ruokinta ja kesyyntyminen ovat tuoneet Sallassa poroja taajamiin, pihoille, pelloille ja teille lisäten liikennevahinkoja. Vahinkokorvaukset nostivat hieman kokonaistulosta, ja maataloustukien myötä se oli yli 7 000 euroa/poronomistaja. Pohjois-Sallassa lähes kaikki poronomistajat saivat puolestaan petokorvauksia ja paliskunta myös vasahävikkikorvausta. Keskimääräinen petovahinkokorvaus kasvoi nelinkertaisesti laskeviin myyntituloihin verrattuna. Poroelinkeinon tulos oli ilman petokorvauksia ja maataloustukia 2 000-7 700 euroa/poronomistaja. Kokonaistulos kasvoi nopeasti ja suuresti petovahinkokorvausten myötä, ja se oli lopulta keskimäärin yli 15 000 euroa/poronomistaja. Kokonaistulos oli Pohjois-Sallan poronomistajilla ja pääasiassa luonnonlaitumilla yli kaksi kertaa suurempi kuin Sallassa. Veroja maksoi molemmissa paliskunnissa vuosittain vain muutama poronomistaja. Tutkimustulosten mukaan poroja pitäisi hoitaa paremman kannattavuuden, mutta myös hyvän imagon vuoksi enemmän luonnonlaitumilla. Porolaidunten riittävyyteen, kuntoon ja poromääriin pitäisi kiinnittää huomiota jo kasvavien liikenne ja petovahinkojen vuoksi koko poronhoitoalueella.

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Puente Ramirez, Norma Patricia, L. M. Torres-Treviño et J. E. Sánchez-Cantú. « Modelado computacional usando regresión lineal y simbólica α β para determinar ópticamente el tamaño del poro de la piel ». Nova Scientia 7, n^o 14 (25 mai 2015) : 218. http://dx.doi.org/10.21640/ns.v7i14.136.

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La apariencia de los poros de la piel normalmente es causada por glándulas sebáceas hiperactivas, sin embargo, en los últimos años se ha reportado que además se ve afectada por diversas enfermedades, entre ellas la diabetes (Jerrold, S Petrofsky, 2008), obesidad (Derraik, Jose GB, 2014) o el cáncer. Generalmente los principales factores que contribuyen a la dilatación de los poros son la edad, el género masculino, el acné, la exposición crónica al sol y la predispocisión genética. El desarrollo de un método no invasivo que permita conocer las condiciones de la piel, ayudara a relacionar los factores que determina el tamaño del poro de la piel. En este trabajo se pretende caracterizar por medio de un modelo computacional y con ayuda de un esquema óptico, el tamaño del poro de la piel. El principio físico consiste en iluminar con leds (543nm) el antebrazo de voluntarios, el esparcimiento de luz generado por la piel es colectada en una camara ccd. La captura de imágenes, el procesamiento y el análisis estadístico son parte de la metodología para la obtención de datos. Se propone un modelo matemático que relaciona género, edad, tono de la piel y tamaño del poro (calculado estadísticamente en las imágenes colectadas ópticamente). Una base de datos se genera y se utiliza para construir matemáticamente modelos mediante regresión simbólica con optimizacion por enjambre de particulas (PSO) y se realiza una comparación por medio de regresión lineal. Algunos indicadores estadísticos como el cuadrado medio de error, error de predicción suma de los cuadrados y porcentaje de variabilidad se utilizan en la comparación. Los resultados indican que el modelo propuesto con el tamaño de los poros de cada individuo puede ayudar a hacer una interpretación objetiva de algunos indicadores de salud.

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Kelder, Oscar, et David M. J. Smeulders. « Observation of the Biot slow wave in water‐saturated Nivelsteiner sandstone ». GEOPHYSICS 62, n^o 6 (novembre 1997) : 1794–96. http://dx.doi.org/10.1190/1.1444279.

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Acoustic signals are used extensively in the oil industry to determine the physical properties of reservoir rock. In the interpretation of these signals empirical laws play a major role. To obtain a more fundamental interpretation of the recorded wavetrains, the need for a comprehensive theory for acoustic wave propagation and damping in rocks is obvious. In this respect, Biot's (1956a,b) theory is a straightforward and effective two‐phase theory. In contrast to Biot, who derived the macroscopic equations for wave propagation in saturated poro‐elastic material by postulating definite positive‐energy density functions, Burridge and Keller (1981), Whitaker (1986a,b,c), and Pride et al. (1992) applied rigorous averaging techniques to derive the poro‐elastic equations from a microscale. De Vries (1989) and Geerits (1996) used the averaging techniques to derive macroscopic poro‐elastic equations for the nonviscous case. The fundamental feature of all these theoretical descriptions is the existence of both a fast and slow compressional wave, as well as a shear wave. For the fast compressional wave, the pore fluid and the porous matrix are compressed simultaneously, but for the slow compressional wave, the porous matrix relaxes while the pore fluid is compressed. The attenuation mechanism for these waves is based on viscous dissipation generated by the flow of the pore fluid relative to the porous matrix. For the slow wave, the viscous dissipation results in a strong, frequency‐dependent attenuation, which makes this wave very difficult to observe in fluid‐saturated rocks. However, because the slow compressional wave is especially sensitive to certain interesting properties of the permeable material, the detection of this slow compressional wave has been one of the major issues in the acoustics of fluid‐saturated permeable solids.

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Sen, Pabitra N., Martin D. Hürlimann et Thomas M. de Swiet. « Debye-Porod law of diffraction for diffusion in porous media ». Physical Review B 51, n^o 1 (1 janvier 1995) : 601–4. http://dx.doi.org/10.1103/physrevb.51.601.

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PUSKARZ, ROMAN, ANDRZEJ SZYMCZYK, SŁAWOMIR SUCHOCKI et JOLANTA KONOPKA. « Comparison of vaginal delivery in water and by the traditional method ». PRZEGLĄD GINEKOLOGICZNO-POŁOŻNICZY 6, n^o 2 (23 mai 2006) : 121–24. http://dx.doi.org/10.1066/s10014060003.

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Girault, Vivette, Mary F. Wheeler, Tameem Almani et Saumik Dana. « A priori error estimates for a discretized poro-elastic–elastic system solved by a fixed-stress algorithm ». Oil & ; Gas Science and Technology – Revue d’IFP Energies nouvelles 74 (2019) : 24. http://dx.doi.org/10.2516/ogst/2018071.

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We consider a poro-elastic region embedded into an elastic non-porous region. The elastic displacement equations are discretized by a continuous Galerkin scheme, while the flow equations for the pressure in the poro-elastic medium are discretized by either a continuous Galerkin scheme or a mixed scheme. Since the overall system of equations is very large, a fixed-stress algorithm is used at each time step to decouple the displacement from the flow equations in the poro-elastic region. We prove a priori error estimates for the resulting Galerkin scheme as well as the mixed scheme, with the expected order of accuracy, provided the algorithm is sufficiently iterated at each time step. These theoretical results are confirmed by a numerical experiment performed with the mixed scheme. A complete analysis including a posteriori estimates for both the Galerkin and the mixed scheme has been done but is too long to appear here.

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Hewitt, Duncan R., Jerome A. Neufeld et Neil J. Balmforth. « Shallow, gravity-driven flow in a poro-elastic layer ». Journal of Fluid Mechanics 778 (5 août 2015) : 335–60. http://dx.doi.org/10.1017/jfm.2015.361.

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By combining Biot’s theory of poro-elasticity with standard shallow-layer scalings, a theoretical model is developed to describe axisymmetric gravity-driven flow through a shallow deformable porous medium. Motivated in part by observations of surface uplift around $\text{CO}_{2}$ sequestration sites, the model is used to explore the injection of a dense fluid into a horizontal, deformable porous layer that is initially saturated with another, less dense, fluid. The layer lies between a rigid base and a flexible overburden, both of which are impermeable. As the injected fluid spreads under gravity, the matrix deforms and the overburden lifts up. The coupled model predicts the location of the injected fluid as it spreads and the resulting uplift of the overburden due to deformation of the solid matrix. In general, the uplift spreads diffusively far ahead of the injected fluid. If fluid is injected with a constant flux and the medium is unbounded, both the uplift and the injected fluid spread in a self-similar fashion with the same similarity variable $\propto r/t^{1/2}$. The asymptotic form of this spreading is established. Results from a series of laboratory experiments, using polyacrylamide hydrogel particles to create a soft poro-elastic material, are compared qualitatively with the predictions of the model.

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Chen, Yijun, Mostafa E. Mobasher, Tao You et Haim Waisman. « Non-local continuum damage model for poro-viscoelastic porous media ». International Journal of Rock Mechanics and Mining Sciences 159 (novembre 2022) : 105212. http://dx.doi.org/10.1016/j.ijrmms.2022.105212.

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Greulich-Weber, Siegmund, et B. Friedel. « Bottom-Up Routes to Porous Silicon Carbide ». Materials Science Forum 615-617 (mars 2009) : 637–40. http://dx.doi.org/10.4028/www.scientific.net/msf.615-617.637.

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We report on constructive methods providing a large range of high purity porous SiC products. All methods are based on modified sol-gel processes combined with carbothermal re¬duction. We obtain monodisperse regular pores of well defined diameters by using carbon sphere templates which are removed after SiC infiltration. A different way is a sol-gel based conversion of graphite bodies into SiC, which transfers the porosity from the graphite matrix into the final SiC product. Thus a large variety of porosity features are available, originating either from natural poro¬sity of graphite or from priorly created nano-/ microstructures in the carbonaceous base material. Whereas all our pristine porous sol-gel derived silicon carbide products are semi-insulating, doping is possible, during the growth to modifiy the electrical and optical properties.

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Ciccariello, Salvino, Yuri B. Melnichenko et Lilin He. « Supercritical carbon dioxide behavior in porous silica aerogel ». Journal of Applied Crystallography 44, n^o 1 (27 novembre 2010) : 43–51. http://dx.doi.org/10.1107/s0021889810045176.

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Analysis of the tails of the small-angle neutron scattering (SANS) intensities relevant to samples formed by porous silica and carbon dioxide at pressures ranging from 0 to 20 MPa and at temperatures of 308 and 353 K confirms that the CO2fluid must be treated as a two-phase system. The first of these phases is formed by the fluid closer to the silica wall than a suitable distance δ and the second by the fluid external to this shell. The sample scattering-length densities and shell thicknesses are determined by the Porod invariants and the oscillations observed in the Porod plots of the SANS intensities. The resulting matter densities of the shell regions (thickness 15–35 Å) are approximately equal, while those of the outer regions increase with pressure and become equal to the bulk CO2at the higher pressures only in the low-temperature case.

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Khokhlov, M. A., et D. A. Ishchenko. « Structural superlight porous metals (Review) ». Paton Welding Journal 2015, n^o 4 (28 avril 2015) : 57–62. http://dx.doi.org/10.15407/tpwj2015.04.08.

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WIĘZNOWSKA-MĄCZYŃSKA, KINGA, BEATA PIĘTA et TOMASZ OPALA. « For and against family labor ». PRZEGLĄD GINEKOLOGICZNO-POŁOŻNICZY 5, n^o 6 (21 décembre 2005) : 351–55. http://dx.doi.org/10.1066/s10014050066.

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Barry, Steven, Geoffrey Aldis et Geoffry Mercer. « Injection of Fluid Into a Layer of Deformable Porous Medium ». Applied Mechanics Reviews 48, n^o 10 (1 octobre 1995) : 722–26. http://dx.doi.org/10.1115/1.3005054.

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The flow of fluid from a point source into a layer of deformable porous material is considered. The main applications of this work are to subcutaneous injections and subterranean soil flows. The porous material is assumed to be an isotropic, homogeneous, linearly elastic solid. The governing equations are derived for an axisymmetric geometry using linear poro-elasticity and are applied to the situation of a point source at some height z = z0 with a line sink at a distance r = ρ. These are solved analytically using Hankel transform techniques with the Hankel inversion integrals calculated numerically. Results are given for the pressure contours and the displacement of the solid matrix for a variety of source heights and elastic parameters. These indicate the swelling of the medium and subsequent deformation of the free surface. Results indicate regions where one dimensional models may be applicable.

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Cabanillas-Casas, Cristopher J., Gustavo Cuba-Supanta, Justo Rojas Tapia et Chachi Rojas-Ayala. « Efectos de forma y tamaño del poro sobre las propiedades mecánicas de las membranas del grafeno nanoporoso ». MOMENTO, n^o 62 (1 janvier 2021) : 63–78. http://dx.doi.org/10.15446/mo.n62.88422.

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En el presente trabajo se estudiaron los efectos de forma y tamaño de los poros sobre las propiedades mecánicas de membranas de grafeno nanoporosas (GNP). Las simulaciones de dinámica molecular fueron ejecutadas para estudiar las respuestas mecánicas y estructurales bajo una tracción uniaxial. Los resultados de las curvas tensión-deformación de las membranas de GNP muestran un comportamiento lineal elástico para razones de deformación pequeñas ($<$0.03) independiente de la dirección quiral. La anisotropía quiral (dirección armchair y zigzag) es notoria conforme se incrementa la deformación hasta el punto de fractura. Las membranas de GNP con poro hexagonal y rectangular presentan una mayor tensión de fractura (65 GPa y 81 GPa, respectivamente). Además, el módulo elástico de Young disminuye conforme se incrementa el tamaño del poro. Se espera que este estudio brinde aplicación práctica como filtros de membranas de alto rendimiento.

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Salvini, V. R., M. D. M. Innocentini et V. C. Pandolfelli. « Influência das condições de processamento cerâmico na resistência mecânica e na permeabilidade dos filtros de Al2O3-SiC ». Cerâmica 48, n^o 307 (septembre 2002) : 121–25. http://dx.doi.org/10.1590/s0366-69132002000300003.

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Filtros cerâmicos devem apresentar alta permeabilidade e eficiência de retenção de inclusões sólidas, além de uma boa resistência mecânica. No entanto, estas propriedades variam de modos distintos para uma determinada estrutura celular. Poros grandes aumentam a permeabilidade, mas diminuem a eficiência de retenção das inclusões. Em relação ao desempenho do filtro, a porosidade aparente apresenta alta relevância, uma vez que a resistência mecânica diminui e a permeabilidade aumenta para valores de porosidade elevados. Neste trabalho investigou-se a relação entre a resistência mecânica e a permeabilidade para filtros do sistema Al2O3-SiC de 10 ppi (poros por polegada linear). A quantidade da suspensão impregnada na esponja, durante a fabricação do filtro, foi escolhida como variável de controle, pois por meio desta modifica-se a porosidade e o tamanho de poro do filtro. Os resultados obtidos foram comparados aos de filtros de 8 a 90 ppi.

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Spalla, O., S. Lyonnard et F. Testard. « Analysis of the small-angle intensity scattered by a porous and granular medium ». Journal of Applied Crystallography 36, n^o 2 (15 mars 2003) : 338–47. http://dx.doi.org/10.1107/s0021889803002279.

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Using X-ray scattering over a large range of scattering vectors, it is shown how to measure both the pore volume fraction and pore specific surface of an assembly of porous grains forming a powder. Depending on the presence or not of solvent in the inner pores and in the intergranular media, the scattered signal per unit volume of solid or per unit volume of grain are introduced, which allow a complete analysis even when the thickness of the layer and its compactness are unknown. The method is applied to three different systems presenting a well defined Porod regime at large scattering vector.

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Bravo Eslava, Luis Manuel, et César Antonio Gallardo Gutiérrez. « Evaluación comparativa de las características de porosidad entre el cemento Portland, MTA y Biodentine con microscopio electrónico de barrido ». Revista Científica Odontológica 9, n^o 1 (12 mars 2021) : e043. http://dx.doi.org/10.21142/2523-2754-0901-2021-043.

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Objetivo: El propósito del presente estudio fue evaluar comparativamente las características de porosidad entre el cemento Portland, MTA Angelus® y Biodentine Septodont®, observados con un microscopio electrónico de barrido. Materiales y métodos: Se prepararon los cementos según las indicaciones del fabricante y se empaquetaron en tubos cilíndricos de polietileno con un diámetro interno de 10 mm y una altura de 5 mm. Se analizó la porosidad de las muestras mediante el microscopio electrónico de barrido. El análisis estadístico se realizó utilizando la prueba Kruskal-Wallis. El nivel de significancia se estableció en 0,05 Resultados: Se observó la descripción de la media de los valores del diámetro de los poros, y el tamaño mayor correspondió al cemento Portland (11,07). Existen diferencias significativas entre las medias del diámetro de los poros con un p = 0,05. Se identificó que el MTA Angelus® tiene la mayor cantidad de poros, le sigue el Biodentine Septodont® y, por último, el Portland. Se comparó la cantidad de poros entre los tres cementos y no se encontraron diferencias significativas, con un p = 0,09. Conclusión: Los análisis realizados en los cementos endodónticos dieron como resultado que el cemento Portland tiene mayor diámetro de poro a diferencia de los otros dos, lo cual implica que tanto el Biodentine Septodont® como el MTA Angelus® tienen mejores propiedades de resistencia y permeabilidad para evitar la microfiltración, y por tanto son mejores para la solución de casos clínicos.

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Vlčková, Michaela. « The Significance of the Ritual of Blessing the Mother after Childbirth ». Studia theologica 15, n^o 1 (1 mars 2013) : 36–46. http://dx.doi.org/10.5507/sth.2013.003.

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López Robledo, M. J., R. E. Sepúlveda Ferrer, A. Bravo León, J. Martínez Fernández et A. R. De Arellano. « Propiedades mecánicas de SiC biomórfico poroso ». Boletín de la Sociedad Española de Cerámica y Vidrio 44, n^o 5 (30 octobre 2005) : 318–23. http://dx.doi.org/10.3989/cyv.2005.v44.i5.363.

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Fedyuk, R., A. Baranov, Yu Ilinsky et Afonso Rangel Garcez de Azevedo. « PERFORMANCES OF HIGH POROUS CELLULAR CONCRETE ». Construction Materials and Products 3, n^o 5 (24 décembre 2020) : 5–14. http://dx.doi.org/10.34031/2618-7183-2020-3-5-5-14.

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The widespread use of cellular concrete for enclosing structures forces researchers to develop ways to im-prove their performance and durability. Compositions of aerated and foam concrete with the use of waste heat power engineering have been developed. The optimal formulation ratios have been identified that con-tribute to the creation of a rigid interpore matrix and water-repellent pore protection. The regularities of the synthesis of aerated concrete and foam concrete were established, which consist in optimizing the processes of structure formation through the use of a polymineral cement-ash binder and a pore-forming agent. The mix composition intensifies the process of hydration of the system, which leads to the synthesis of a poly-mineral highly porous heterodispersed matrix. The increased activity and granulometry of aluminosilicates predetermine an increase in the number of contacts and mechanical adhesion between particles during com-paction, strengthening the framework of the interpore partitions. The mechanism of the influence of the composition of the concrete mix on the microstructure of the composite is established. The calculated sound insulation of airborne noise shows sufficient characteristics for using aerated concrete blocks as enclosing structures. One of the main advantages of aerated concrete is its low thermal conductivity, which is especial-ly important from the point of view of ensuring the energy efficiency of buildings and structures. Even in spite of the high values of open porosity of the developed aerated concrete, the rigid frame makes it possible to achieve almost 2 times higher frost resistance characteristics than that of the reference specimen

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Lan, Yuan-Jyh, Tai-Wen Hsu et Ching-Yu Chen. « ANALYSIS OF WAVE INTERACTION WITH SUBMERGED ADJACENT PORO-ELASTIC BREAKWATERS ». Coastal Engineering Proceedings 1, n^o 33 (15 octobre 2012) : 31. http://dx.doi.org/10.9753/icce.v33.structures.31.

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In this study, the problem of wave interaction with two closely submerged adjacent porous elastic breakwaters is investigated theoretically. The porous elastic breakwaters are assumed to be homogeneous, isotropic and elastic. Lan and Lee’s (2010) analytical solution is extended to the problem subject to proper boundary conditions. Using general solutions for each region and the matching boundary conditions, a set of simultaneous equations is thus developed and solved numerically. The present analytic solutions compare favorably with simplified cases of the poro-elastic submerged breakwater. Changes of the width of two adjacent breakwaters, the permeable coefficient effect on wave profile, and the effect of materials and configurations of breakwaters on wave variation are the focus of the present paper. The results show that a large amount of energy dissipates when the adjacent structures both have the same soft material and dimension of width with higher permeability. Different materials and shapes of structures could significantly influence the reflection coefficient.

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Rivera Pineda, Zulay Marcela, Ingrid Milena Rivera Pineda, Dennis Alexander Lugo, Marlín Guía Yanes, Carmen Bastidas Díaz, Isabel Hagel López et Víctor Arturo Ollarves Ruiz. « Caracterización de la población con obstrucción de poros faciales a quienes se les aplico laserterapia en la Unidad de Dermatología UNIMEL ». Revista Vive 3, n^o 9 (9 juin 2021) : 129–38. http://dx.doi.org/10.33996/revistavive.v3i9.53.

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Introducción: El poro es un orificio de excreción que se encuentra en la epidermis de la piel, en donde pueden producirse problemas de eliminación deficiente del sebo en personas que presentan exceso de grasas. Objetivo: Analizar las características y tratamiento laser aplicado a la población con obstrucción de poros faciales que acuden a la consulta de la Unidad de Dermatología UNIMEL. Materiales y métodos: Estudio descriptivo, de campo, prospectivo y transversal, la población fue de 653 pacientes de ambos sexos que acudieron a la consulta de dermatología y recibieron laserterapia por presentar obstrucción de poros faciales. Se aplicó estadística descriptiva para la representación de datos. El instrumento utilizado fue una lista de registro. Resultados: Los pacientes presentaron una edad promedio de 37 años, se aplicaron diferentes tratamientos según los criterios diagnósticos, se les realizó el procedimiento de fotona Black peel en un 0,15%, Vela de Nova en un 5,05% y Qs Quimioespectra a un 94,79% que representan un total de 619 personas. Conclusión: El mayor grupo de pacientes que asistió a tratamiento se ubicó entre los 31 a 40 años de edad, un alto porcentaje mujeres afectadas por secuelas de daño facial producido por obstrucción de los poros y acumulación de sebo, un grupo importante 48,8% presenta acné posterior a los 18 años de edad.

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Behrou, Reza. « A Thermo-Poro-Viscoelastic Model for the Behavior of Polymeric Porous Separators ». ECS Transactions 80, n^o 8 (24 août 2017) : 583–91. http://dx.doi.org/10.1149/08008.0583ecst.

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Ma, Li. « Porous media equation on locally finite graphs ». Archivum Mathematicum, n^o 3 (2022) : 177–87. http://dx.doi.org/10.5817/am2022-3-177.

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Patil, Vaibhav, Pooja Patil et Jayashree Patil Mrunal Patil Kirtee Sawant Mr S. P. Patil. « A Research Paper on Porous Asphalt Pavement ». International Journal of Trend in Scientific Research and Development Volume-2, Issue-4 (30 juin 2018) : 2026–31. http://dx.doi.org/10.31142/ijtsrd14516.

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Esipov, I. B., S. A. Rybak et A. N. Serebryanyi. « Nonlinear acoustic diagnostics of the ocean and rock ». Uspekhi Fizicheskih Nauk 176, n^o 1 (2006) : 102. http://dx.doi.org/10.3367/ufnr.0176.200601h.0102.

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Szilágyi, Katalin, Adorján Borosnyói et Zoltán Gyurkó. « Static hardness testing of porous building materials ». Epitoanyag-Journal of Silicate Based and Composite Materials 65, n^o 1 (2013) : 6–10. http://dx.doi.org/10.14382/epitoanyag-jsbcm.2013.2.

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Gloaguen, Thomas Vincent, Francisco Adriano de Carvalho Pereira, Roberta Alessandra Bruschi Gonçalves et Vital da Silva Paz. « Composição química da solução do solo nas diferentes classes de poro do solo ». Revista Brasileira de Ciência do Solo 33, n^o 5 (octobre 2009) : 1105–13. http://dx.doi.org/10.1590/s0100-06832009000500004.

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A composição química da solução do solo pode ser considerada indicadora da presença de nutrientes ou contaminantes no solo. Para analisar a variação dessa composição nos poros do solo, utilizou-se um sistema de extração sequencial da solução do solo em diferentes classes de diâmetro de poro. Colunas de PVC foram construídas e preenchidas com terra fina seca ao ar de um Cambissolo Háplico distrófico, e irrigadas com água destilada (T1), efluente de estação de tratamento de esgoto sanitário EETE (T2) e EETE + 1,2 g L-1 CaSO4 (T3), aplicando lâminas de 150 e 300 mm. Antes da irrigação e após cada lâmina, aplicaram-se na base de cada coluna os seguintes potenciais: 0, 13,3, 26,7, 40,0 e 53,3 kPa para extração e coleta da solução do solo nas faixas de poros: Ø > 76,2 µm, 44,6 < Ø < 76,2 µm, 29,6 < Ø < 44,6 µm, 25,2 < Ø < 29,6 µm, e 23,3 < Ø < 25,2 µm. Os atributos analisados nas soluções extraídas foram pH, condutividade elétrica e as concentrações de Na+, Ca2+, NO3-e NH4+. A variação das concentrações iônicas na porosidade do solo foi semelhante, sendo 3 a 10 vezes maior na microporosidade (Ø < 44,6 m) do que na macroporosidade (Ø > 44,6 m). Todos os dados foram ajustados significativamente ao modelo linear Y = a - b.log(X), onde Y é o atributo avaliado e X o diâmetro de poro do solo. Embora a concentração de NO3-na microporosidade supere o valor limite [NO3-]lim para água doce potável (Classe 1), a baixa concentração na macroporosidade (sempre inferior a [NO3-]lim/4) limita o risco de contaminação por lixiviação. Constatou-se também que a adição de gesso promove a redução da concentração de NO3-e de Na+ no solo.

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S. Wong, Z., C. C. Liao et D. S. Jeng. « 3-D Poro-Elastoplastic Model for Short-Crested Wave-Induced Pore Pressures in a Porous Seabed ». Open Civil Engineering Journal 9, n^o 1 (10 juillet 2015) : 408–16. http://dx.doi.org/10.2174/1874149501509010408.

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In this paper, a three-dimensional poro-elastoplastic model for the short-crested wave-induced pore pressures in a porous seabed is presented. Unlike the previous models, both elasticity and plasticity of seafloor are considered in the present model. This study considers the effects of wave and soil characteristics on the pore pressures and was validated with the previous wave experiment data. As the numerical analysis shows, higher value of plastic parameter leads to a faster residual pore pressure accumulation, which is closely related to the occurrence of seabed liquefaction. In particular, at the dissipation stage, residual pore pressure sharply decreases when enlarging plastic parameter , which dominates the velocity of accumulation of plastic volumetric strain.

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Misharina, Tamara. « Headspace Analysis of Aroma Compounds Using Porous Adsorbents ». Chemistry & ; Chemical Technology 5, n^o 3 (15 septembre 2011) : 347–54. http://dx.doi.org/10.23939/chcht05.03.347.

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Semenyuk, Nataliya, Ulyana Kostiv, Oleg Suberlyak et Volodymyr Skorokhoda. « Peculiarities of Filled Porous Hydrogels Production and Properties ». Chemistry & ; Chemical Technology 7, n^o 1 (10 mars 2013) : 95–99. http://dx.doi.org/10.23939/chcht07.01.095.

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Suhail, Abdulla M. « Carbon nanotubes -porous silicon high sensitivity infrared detector ». International Journal of Scientific Research 2, n^o 1 (1 juin 2012) : 209–10. http://dx.doi.org/10.15373/22778179/jan2013/74.

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