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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
501

Lithology constraints from seismic waveforms : application to opal-A to opal-CT transition

Maysami, Mohammad 05 1900 (has links)
In this work, we present a new method for seismic waveform characterization, which is aimed at extracting detailed litho-stratigraphical information from seismic data. We attempt to estimate the lithological attributes from seismic data according to our parametric representation of stratigraphical horizons, where the parameter values provide us with a direct link to nature of lithological transitions. We test our method on a seismic dataset with a strong diagenetic transition (opal-A to opal-CT transition). Given some information from cutting samples of well, we use a percolation-based model to construct the elastic profile of lithological transitions. Our goal is to match parametric representation for the diagenetic transition in both real data and synthetic data given by these elastic profiles. This match may be interpreted as a well-seismic tie, which reveals lithological information about stratigraphical horizons. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
502

Proteomic Characterization of Hemogen in Erythropoiesis

Somasundaram, Brinda January 2012 (has links)
Hemogen (Hemgn) is reported as a tissue specific transcriptional regulator in testis as well as hematopoietic tissues. It is known that Hemgn positively regulates erythroid differentiation; however,the underlying molecular mechanism is not well understood. In the current study, using proteomic approach in combination with other molecular biology tools,we have attempted to decipher the role of Hemgn in differentiating Murine erythroblast leukemia (MEL) cells as a model system. Our study reveals that Hemgn predominantly interacts with transcriptional regulators, chromatin modifiers and histones. Furthermore, using Chromatin Immunoprecipitation and knockdown approach, we have demonstrated that Hemgn is recruited to the b-globin locus, which is known to be activated during erythroid differentiation. Based on the results,we speculate that Hemgn acts as a tissue specific histone chaperone that regulates transcription during erythroid differentiation.
503

Vehicular Cloud: Stochastic Analysis of Computing Resources in a Road Segment

Zhang, Tao January 2016 (has links)
Intelligent transportation systems aim to provide innovative applications and services relating to traffic management and enable ease of access to information for various system users. The intent to utilize the excessive on-board resources in the transportation system, along with the latest computing resource management technology in conventional clouds, has cultivated the concept of the Vehicular Cloud. Evolved from Vehicular Networks, the vehicular cloud can be formed by vehicles autonomously, and provides a large number of applications and services that can benefit the entire transportation system, as well as drivers, passengers, and pedestrians. However, due to high traffic mobility, the vehicular cloud is built on dynamic physical resources; as a result, it experiences several inherent challenges, which increase the complexity of its implementations. Having a detailed picture of the number of vehicles, as well as their time of availability in a given region through a model, works as a critical stepping stone for enabling vehicular clouds, as well as any other system involving vehicles moving over the traffic network. The number of vehicles represents the amount of computation capabilities available in this region and the navigation time indicates the period of validity for a specific compute node. Therefore, in this thesis, we carry out a comprehensive stochastic analysis of several traffic characteristics related to the implementation of vehicular cloud inside a road segment by adopting proper traffic models. According to the analytical results, we demonstrate the feasibility of running a certain class of applications or services on the vehicular cloud, even for highly dynamic scenarios. Specifically, two kinds of traffic scenarios are modeled: free-flow traffic and queueing-up traffic. We use a macroscopic traffic model to investigate the free-flow traffic and analyze the features such as traffic density, the number of vehicles and their residence time. Also, we utilize the queueing theory to model the queueing-up traffic; the queue length and the waiting time in the queue are analyzed. The results show the boundaries on enabling vehicular cloud, allowing to determine a range of parameters for simulating vehicular clouds.
504

Material Characterization of Cardiovascular Biomaterials Using an Inverse Finite Element Method

Nightingale, Miriam January 2017 (has links)
Being able to accurately model soft tissue behaviour, such as that of heart valvular tissue, is essential for developing effective numerical simulations of in-vivo conditions and determining patient-specific care options. Although several analytical material models, based on strain energy functions, have been successful in predicting soft tissue behaviour, complications arise when these models are implemented into finite element (FE) programs due to the incorporation of a penalty parameter for numerically enforcing material incompressibility. Specifically, material parameters determined through non-FE methods may no longer produce a material behaviour that reflects the experimental behaviour once they are used in an FE analysis. Based on commercial finite element software LS-DYNA, an inverse methodology was developed in MATLAB to simultaneously optimize the material parameters and the penalty parameter for the Guccione strain energy model. The methodology produced accurate predictions of the material behaviour under planar equibiaxial testing for five biomaterials used in heart valve cusp replacements.
505

Assessing hydrocarbon potential in cretaceous sediments in the Western Bredasdorp Sub-basin in the Outeniqua Basin South Africa

Acho, Collins Banajem January 2015 (has links)
>Magister Scientiae - MSc / The Bredasdorp Basin is one of the largest hydrocarbon producing blocks within Southern Africa. The E-M field is situated approximate 50 km west from the FA platform and was brought into commission due to the potential hydrocarbons it may hold. If this field is brought up to full producing capability it will extend the lifespan of the refining station in Mosselbay, situated on the south coast of South Africa, by approximately 8-10 years. This study is focused in block 9 off shore western part of the Bredasdorp Basin in the main Outeniqua Basin South Africa. Cretaceous Sandstone reservoirs are commonly heterogeneous consequently they may require special methods and techniques for description and evaluation. Reservoir characterization is the study of the reservoir rocks, their petrophysical properties, the fluids they contain or the manner in which they influence the movement of fluids in the subsurface. The main goal of the research is to assess the potentials of hydrocarbons in Cretaceous sediments in the Bredasdorp Basin through the integration and comparison of results from core analysis, production data and petrography studies for the evaluation and correction of key petrophysical parameters from wireline logs which could be used to generate an effective reservoir model for wells (E-BB1, E-BD2, EA01) in the Bredasdorp Basin. Porosity and permeability relationships, wire-line log data have been examined and analysed to determine how the porosity and permeability influence reservoir quality which further influences the potential of hydrocarbon accumulation in the reservoirs. The reservoir sandstone is composed mainly of fine to medium grained Sandstones with intercalation of finger stringers of Siltstone and Shale. In carrying out this research the samples are used to characterize reservoir zones through core observation, description and analyses and compare the findings with electronic data obtained from Petroleum Agency of South Africa (PASA). Secondary data obtained from (PASA) was analysed using softwares such as Interactive Petrophysics (IP), Ms Word, Ms excel and Surfer. Wireline logs of selected wells (E-BB1, E-BD2, E-A01) were generated, analysed and correlated. Surfer software also used to digitize maps of project area, porosity and permeability plotted using IP. Formation of the Bredasdorp Basin and it surrounding basins during the Gondwana breakup. The Bredasdorp Basin consists mainly of tilting half graben structures that formed through rifting with the break-up of Gondwanaland. The model also revealed that these faults segregate the reservoir which explains the pressure loss within the block. The production well was drilled, confining pressure relieved and pressure dropped hence production decreases. The age, transportation, deposition and thermal history of sediment in the basin, all plays a vital role in the type of hydrocarbon formation. Structural features such as faults, pore spaces determines the presence of a hydrocarbon in the reservoir. Traps could be stratigraphic or structural which helps prevent the migration of hydrocarbons from the source rock to reservoir rock or from reservoir rock to the surface over a period of time. The textural aspects included the identification of grain sizes, sorting and grain shapes. The diagenetic history, constructed from the results of the reservoir quality study revealed that there were several stages involved in the diagenetic process. It illustrated several phases of cementation with quartz, carbonate and dolomite with dissolution of feldspar. A potentially good reservoir interval was identified from the data and was characterized by several heterogeneous zones. Identifying reservoir zones was highly beneficial during devising recovery techniques for production of hydrocarbons. Secondary recovery methods have thus been devised to enhance well performance. As recommendation, additional wells are required to appraise the E-M structure and determine to what extent the cement present in the basin has affected fluid flow as well as the degree of sedimentation that could impede fluid flow. There are areas still containing untapped resources thus the recommendation for extra wells. This research may well be reviewed with more data input from PetroSA (wells, seismic and production data) for additional studies, predominantly with respect to reservoir modelling and flow simulation. Based on the findings of this research, summary of calculated Net Pay shows that in well E-BB1, reservoir (1) is at depth 2841.5m – 2874.9m has a Gross Thickness of 33.40m, Net Pay of 29.72 and Pay Summary of 29.57 and reservoir (2) has depth of 2888.1m – 2910.5m, Gross Thickness of 22.40m, Net Pay of 19.92m and Pay summary of 1.48m. Well E-AO1 has depth from 2669.5m – 2684.5m and Gross Thickness of 15.00m and has Net Pay of 10.37m and Pay Summary of 10.37m. Based on the values obtained from the data analysed the above two wells displays high potential of hydrocarbon present in the reservoirs. Meanwhile well E-BD2 has depth from 2576.2m – 2602.5m and has Gross Thickness of 350.00m, Net Pay of 28.96m and Pay Summary of 4.57 hence from data analysis this reservoir displays poor values which is an indication of poor hydrocarbon potentials.
506

Modeling, Simulation, and Characterization of Space Debris in low-Earth Orbit

McCall, Paul D 15 November 2013 (has links)
Every space launch increases the overall amount of space debris. Satellites have limited awareness of nearby objects that might pose a collision hazard. Astrometric, radiometric, and thermal models for the study of space debris in low-Earth orbit have been developed. This modeled approach proposes analysis methods that provide increased Local Area Awareness for satellites in low-Earth and geostationary orbit. Local Area Awareness is defined as the ability to detect, characterize, and extract useful information regarding resident space objects as they move through the space environment surrounding a spacecraft. The study of space debris is of critical importance to all space-faring nations. Characterization efforts are proposed using long-wave infrared sensors for space-based observations of debris objects in low-Earth orbit. Long-wave infrared sensors are commercially available and do not require solar illumination to be observed, as their received signal is temperature dependent. The characterization of debris objects through means of passive imaging techniques allows for further studies into the origination, specifications, and future trajectory of debris objects. Conclusions are made regarding the aforementioned thermal analysis as a function of debris orbit, geometry, orientation with respect to time, and material properties. Development of a thermal model permits the characterization of debris objects based upon their received long-wave infrared signals. Information regarding the material type, size, and tumble-rate of the observed debris objects are extracted. This investigation proposes the utilization of long-wave infrared radiometric models of typical debris to develop techniques for the detection and characterization of debris objects via signal analysis of unresolved imagery. Knowledge regarding the orbital type and semi-major axis of the observed debris object are extracted via astrometric analysis. This knowledge may aid in the constraint of the admissible region for the initial orbit determination process. The resultant orbital information is then fused with the radiometric characterization analysis enabling further characterization efforts of the observed debris object. This fused analysis, yielding orbital, material, and thermal properties, significantly increases a satellite’s Local Area Awareness via an intimate understanding of the debris environment surrounding the spacecraft.
507

Caracterização biológica e molecular de cepas de Trypanosoma cruzi Chagas, 1909 (Kinetoplastida, Trypanosomatidae) isoladas da Bahia, Rio Grande do Sul, Santa Catarina e São Paulo / Biological and molecular characterization of strains of Trypanosoma cruzi Chagas, 1909 (Kinetoplastida, Trypanosomatidae) isolated from Bahia, Rio Grande do Sul, Santa Catarina and São Paulo

Ribeiro, Aline Rimoldi, 1980- 12 January 2014 (has links)
Orientadores: João Aristeu da Rosa, Mário Steindel / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-27T12:48:03Z (GMT). No. of bitstreams: 1 Ribeiro_AlineRimoldi_D.pdf: 21726449 bytes, checksum: 28ac88cc86cc90e738eb70f9dca45f0b (MD5) Previous issue date: 2014 / Resumo: Trypanosoma cruzi, protozoário que faz parte da família Trypanosomatidae é o agente causador da doença de Chagas que afeta 6-8 milhões de pessoas na América Latina. A origem dessa família pode ser estudada por meio de técnicas moleculares, como a investigação da região V7V8 - SSUrRNA. Trypanosoma cruzi é subdividido em seis grupos independentes TcI-TcVI denominados Unidades Discretas de Tipagem (DTUs). A caracterização biológica e molecular de onze cepas de T. cruzi pertencentes aos grupos TcI (Bolívia; Tlenti; Tmelanocephala; SC90), TcII (Famema; SC96; SI8; Y) e TcIII (QMM3; QMM5; SI5) isoladas de cinco espécies de triatomíneos esclarece fatores biológicos por parâmetros como a cinética de crescimento, curva parasitêmica, taxa de infeção celular, caracterização molecular, ação de metaloproteinases, perfil protéico e sorologia. O objetivo do trabalho foi a caracterização biológica e molecular de cepas de T. cruzi isoladas de triatomíneos da Bahia, Rio Grande do Sul, Santa Catarina e São Paulo. O grupo TcII de T. cruzi mostrou maior capacidade multiplicativa em formas epimastigotas durante a cinética de crescimento, seguido por TcI e TcIII. A curva parasitêmica evidenciou variabilidade entre os camundongos Balb/c, contudo ao comparar os grupos TcI, TcII e TcIII de T. cruzi o perfil parasitêmico mostrou-se equivalente. Acrescentando os dados biológicos estudou-se a taxa de infecção de T. cruzi em linhagens celulares J774 e macrófagos peritoneais. O grupo TcI de T. cruzi apresentou maior taxa de infecção e menor tempo exigido para a multiplicação de formas amastigotas, assim como macrófagos peritoneias mostraram-se mais atrativos para T. cruzi. A caracterização molecular, por meio da região V7V8, mostrou que essas cepas pertencem às DTUs TcI, TcII e TcIII. A separação dos grupos torna-se evidente ao comparar o perfil protéico em formas epi e tripomastigotas de T. cruzi. O grupo TcI apresentou mais proteínas nos géis de acrilamida, particularidade que pode ser associada a intra-específicidade de TcI. A ação de metaloproteinases foi observada em formas epi e tripomastigotas sugerindo presença ativa e estável durante parte do ciclo do parasito. A reatividade sorológica foi comprovada nos grupos TcI, TcII e TcIII, por meio de ELISA em diluições de 1/100 até 1/12.800. A adição da técnica de Western Blotting aos ensaios por SDS-PAGE em soros de animais infectados após 50 dias mostrou o perfil protéico da cepa Y em membrana de nitrocelulose. Em conjunto, os resultados mostraram que as onze cepas de T. cruzi apresentaram diferenças entre os grupos do parasito. O grupo TcI mostrou maior taxa de infecção em células; TcII, os maiores valores para a cinética de crescimento e TcIII filogenéticamente próximo a TcV, grupo híbrido. A associação parasito-hospedeiro pode explicar diferenças biológicas e moleculares em cepas de T. cruzi, neste sentido o estudo de onze cepas isoladas de diferentes hospedeiros pode agregar informações a literatura e esclarecer alguns aspectos biológicos desse patógeno / Abstract: Trypanosoma cruzi, a protozoan from the family Trypanosomatidae, is responsible for Chagas disease which affects about 6 to 8 million people in Latin America. The origin of this family can be studied through molecular techniques, for instance the investigation of the region V7V8 ¿ SSurRNA. The protozoan is subdivided in six independents groups TcI-TcVI known as Discrete Typing of Units (DTUs). The biological and molecular characterization of eleven strains of T. cruzi from the group TcI (Bolivia; Tlenti; Tmelanocephala; SC90), TcII (Famema; SC96; SI8; Y) and TcIII (QMM3; QMM5; SI5) isolated from five different species of triatomine are able to elucidate biological factors through the kinetic growth, parasitemic curve, cell infection rate, molecular characterization, metalloproteinase action, proteic and serological profile. This investigation was conducted to provide a biological and molecular characterization of T. cruzi isolated from specimens of triatomines. The group TcII of T. cruzi demonstrated higher replicative capacity in epimastigotes forms during the kinetic growth curve, followed by TcI and TcIII. The parasitemic curve demonstrated variability between Balb/c mice; however, the groups TcI, TcII and TcIII showed equivalent parasitemic profile. Furthermore, the cell infection rate in J774 cellular lineages and peritoneal macrophages was used to corroborate the biological data. The group TcI of T. cruzi demonstrated higher infection rate and less time to amastigotes forms multiplication and the peritoneal macrophages showed more attractive to T. cruzi. The molecular characterization through the V7V8 region indicated that these strains belong to DTUs TcI, TcII and TcIII. The groups segregation is important to compare the proteic profile of epimastigotes and tripomastigotes forms of T. cruzi. The groups TcI presented more proteins in acrylamide gels, which can be associated with intra-specif of TcI. The metalloproteinase action was observed in epimastigotes and tripomastigotes forms, demonstrating active and stable presence at the parasite life cycle. The serological reactivity was proven in the groups TcI, TcII and TcIII through ELISA dilutions of 1/100 to 1/12.800. Moreover, the Western Blotting technique was added to SDS-PAGE experiments in infected animals¿ serum after 50 dias and the proteic profile of Y strain was observed in nitrocellulose membrane. The results demonstrated that these eleven strains of T. cruzi have differences between the groups of the parasite. The group TcI showed higher infection rate in cells; TcII, higher value for kinetic growth and TcIII is phylogenetically closer to TcV, which is a hybrid group. The association between parasite and host is able to explain the biological and molecular differences in T. cruzi strains; for this reason, the study of eleven strains isolated from different hosts can add information to the literature and clarify some of the biological aspects of the parasite / Doutorado / Parasitologia / Doutora em Parasitologia
508

Estudo experimental da pirólise lenta de bambu da espécie Dendrocalamus giganteus Munro e avaliação das propriedades do bio-óleo gerado no processo / Experimental study of the slow pyrolysis of bamboo species Dendrocalamus giganteus Munro, and evaluation of bamboo bio-oil properties

Jiménez Chacón, Suranny, 1984- 28 August 2018 (has links)
Orientador: Araí Augusta Bernárdez Pécora / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-28T12:10:13Z (GMT). No. of bitstreams: 1 JimenezChacon_Suranny_M.pdf: 86052116 bytes, checksum: 756e1de65a13a7a1cea018a1ed3d9ff2 (MD5) Previous issue date: 2015 / Resumo: Uma vez que o desafio das novas gerações de pesquisadores é encontrar combustíveis renováveis e não agressivos ao meio ambiente, com propriedades similares ou superiores às dos combustíveis fósseis não renováveis, a busca por uma forma alternativa de combustível é cada vez mais recorrente. Visto que os recursos fósseis estão cada vez mais escassos, pode-se considerar que a busca de combustíveis alternativos é um desafio que marca a atualidade, pois consequentemente impulsiona o desenvolvimento de ideias inovadoras com a finalidade de substituir os combustíveis utilizados tradicionalmente. Sendo assim, uma linha de pesquisa que emerge oferecendo uma proposta a este problema é aquela baseada na utilização de biomassas para geração de biocombustíveis. Dado estes fatos, o objetivo deste projeto é estudar experimentalmente a pirólise lenta de bambu da espécie Dendrocalamus giganteus Munro em reator mecanicamente agitado, visando determinar o rendimento dos produtos (carvão vegetal, líquido e gás) para cada condição ensaiada e, posteriormente, avaliar as propriedades físico-químicas do bio-óleo gerado na condição em que ocorreu seu máximo rendimento. O bio-óleo foi coletado de forma fracionada em quatro diferentes faixas de temperatura (20 ¿ 220 ºC, 220 ¿ 300 ºC, 300 ¿ 400 ºC e 400 ¿ 500 ºC) com o objetivo de verificar os rendimentos e propriedades do líquido gerado em cada uma dessas faixas de temperatura. A descoberta de possíveis aplicações para o bio-óleo do bambu contribuiria para a viabilidade econômica do processo de produção de carvão de bambu, produto principal em reatores de pirólise lenta. Os ensaios de pirólise foram feitos seguindo um planejamento experimental 2^2 mais pontos centrais (DOE ¿ Design of experiments), com a finalidade de determinar a influência da velocidade de agitação (20 a 60 rpm) e do tempo de residência (10 a 30 min) sobre o rendimento do bio-óleo gerado. Os resultados indicaram que o melhor rendimento do bio-óleo (~ 53 %) ocorreu na condição em que a agitação do rotor estava em 60 rpm e 30 min de tempo de residência do sólido. O maior PCS do bio-óleo foi de 28,7 MJ/kg, correspondente à fração coletada entre 300 e 400 ºC / Abstract: Once the challenge of new generations of researchers is to find renewable fuels that are not harmful to the environment, and showing properties similar or superior to those of non-renewable fossil fuels, the search for an alternative form of fuel is becoming more recurrent. Since the fossil resources are increasingly scarce, it can be considered that the search for alternative fuels is a challenge that marks the present time, because it consequently drives the development of innovative ideas in order to replace the traditional fuels. Thus, a line of research that emerges offering a proposal to this problem is based on the use of biomass for generating biofuels. Given these facts, the aim of this project is to study, experimentally, the slow pyrolysis of bamboo Dendrocalamus giganteus Munro in a mechanically agitated reactor, in order to determine the yield of products (charcoal, bio-oil and gas) for each test condition and subsequently evaluate the physicochemical properties of bio-oil generated in the condition in which the maximum efficiency occurred. The bio-oil was collected in separated portions at four different temperature ranges (20 ¿ 220 ºC, 220 ¿ 300 ºC, 300 ¿ 400 ºC e 400 ¿ 500 ºC) in order to verify yield and properties in each of these temperature ranges. The discovery of possible applications for the bamboo bio-oil will contribute to the economic viability of production process of bamboo charcoal, the main product of slow pyrolysis reactors. The pyrolysis experimental tests were made following a factorial design 2^2 more central points (DOE - Design of Experiments), with the purpose of determining the influence of agitation speed (20 to 60 rpm) and residence time (10 to 30 min) on yield generated from the process. The results indicated that the best bio-oil yield (~ 53 %) occurred in the condition in which the rotor agitation was 60 rpm and the solid residence time was 30 min. The highest heating value of the bio-oil was 28,7 MJ/kg, corresponding to the fraction collected between 300 and 400 °C / Mestrado / Termica e Fluidos / Mestra em Engenharia Mecânica
509

Novel Approaches for Improving Efficiency and Stability of Next Generation Perovskite Solar Cells

January 2020 (has links)
abstract: Perovskite solar cells are the next generation organic-inorganic hybrid technology and have achieved remarkable efficiencies comparable to Si-based conventional solar cells. Since their inception in 2009 with an efficiency of 3.9%, they have improved tremendously over the past decade and recently demonstrated 25.2% efficiency for single-junction devices. There are a few hurdles, however, that prevent this technology from realizing their full potential, such as stability and toxicity of the perovskites. Apart from solution processing in the fabrication of perovskites, precursor composition plays a major role in determining the quality of the thin film and its general properties. This work studies novel approaches for improving the efficiency and stability of the perovskite solar cells with minimized toxicity. The effect of excess Pb on photo-degradation in MAPbI3 perovskites in an inverted device architecture was studied with a focus on improving stability and efficiency. Precursor concentration with 5% excess Pb was found to be optimal for better efficiency and stability against photo-degradation. Further improvements in efficiency were made possible through the addition of Zirconium Acetylacetonate as a secondary electron buffer layer. A concentration of 1.5mg/ml was found to be optimal for demonstrating better efficiency and stability. Partial substitution of Pb with non-toxic Sr was also studied for improving the stability of inverted devices. Using acetate-derived precursors, 10% Sr was introduced into perovskites for improvements to the stability of the device. In another study, triple-cation perovskites with FAMACs cations were studied with doping different amounts of Phenyl Ethyl Ammonium (PEA) to induce a quasi 2D-3D structure for improved moisture stability. Doping the perovskite with 1.67% PEA was found to be best for improved morphology with fewer pinholes, which further resulted in better VOC and stability. A passivation effect for triple-cation perovskites was further proposed with the addition of a Guanidinium Iodide layer on the perovskite. Concentrations of 1mg/ml and 2mg/ml were demonstrated to be best for reducing defects and trap states and increasing the overall stability of the device. / Dissertation/Thesis / Doctoral Dissertation Materials Science and Engineering 2020
510

Novel Techniques to Characterize Pore Size of Porous Materials

Alabdulghani, Ali J. 24 April 2016 (has links)
Porous materials are implemented in several industrial applications such as water desalination, gas separation and pharmaceutical care which they are mainly governed by the pore size and the PSD. Analyzing shale reservoirs are not excluded from these applications and numerous advantages can be gained by evaluating the PSD of a given shale reservoir. Because of the limitations of the conventional characterization techniques, novel methods for characterizing the PSD have to be proposed in order to obtain better characterization results for the porous materials, in general, and shale rocks in particular. Thus, permporosimetry and evapoporometry (EP) technologies were introduced, designed and utilized for evaluating the two key parameters, pore size and pore size distribution. The pore size and PSD profiles of different shale samples from Norway and Argentina were analyzed using these technologies and then confirmed by mercury intrusion porosimeter (MIP). Norway samples showed an average pore diameter of 12.94 nm and 19.22 nm with an average diameter of 13.77 nm and 23.23 nm for Argentina samples using permporosimetry and EP respectively. Both techniques are therefore indicative of the heterogeneity of the shales. The results from permporosimetry are in good agreement with those obtained from MIP technique, but EP for most part over-estimates the average pore size. The divergence of EP results compared to permporosimetry results is referred to the fact that the latter technique measures only the active pores which is not the case with the former technique. Overall, both techniques are complementary to each other which the results from both techniques seem reasonable and reliable and provide two simple techniques to estimate the pore size and pore size distributions for shale rocks.

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