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GPR Tomographic Imaging of Concrete Tubes and Steel/Plastic Tanks Buried in IAG/USP Geophysical Test Site, Brazil

International Journal of Geosciences 2017年第5期8卷 647-658页

作者： Jorge Luís Porsani emerson rodrigo almeida Bruno Poluha Vinícius Rafael Neris dos Santos Universidade de Sã o Paulo Instituto de Astronomia Geofísica e Ci&ecirc ncias Atmosféricas Departamento de Geofísica. Rua do Mat&atilde o 1226 Butant&atilde S&atilde o Paulo Brazil

In this paper, the Ground Penetrating Radar (GPR) method was used to characterize concrete tubes and steel/plastic tanks buried in IAG/USP test site. The microwave tomography was used to improve the GPR images, aiming to retrieve the geometry of the targets. The numerical modeling studies also were done in order to predict the GPR results of the buried targets and to give more reliability to the results interpretation. The targets were installed in the first shallow geophysical test site of the Brazil located at Institute of Astronomy, Geophysics, and Atmospheric Science (IAG) of the University of S?o Paulo (USP). GPR profiles of 200 MHz (shielded bistatic antennas) were acquired along three lines containing concrete tubes and steel/plastic tanks buried in subsoil. The concrete tubes show a hyperbolic reflector for the top, and the vertical tube also presented a reflection on its bottom. The horizontal steel tanks were characterized by a strong GPR reflection on their top. The empty plastic tank shows a strong reflector for the top with normal polarity. On the other hand, the plastic tank filled with water shows a weaker reflector for its top characterized by the inverted polarity of GPR signal when compared with empty plastic tank. The plastic tank filled with water also went characterized by the strong reflection to its bottom, being a good indicative to interpret GPR data on target in subsoil with some types of fluid inside of tank. The results of polarity difference for the top of tank can be used as guide pattern to identify buried tank empty or filled with water. The application of microwave tomography to the GPR data permitted to determine the position and get a good identification of the edges of the targets studied. The numeric modeling presented a good accordance with real data reducing the ambiguities in interpretation of results. These results can be used as a reference, and they can be extrapolated for areas where there is no subsurface information.

关键词： Ground Penetrating Radar (GPR) Microwave Tomography Numeric Modeling Concrete Tubes Steel Tanks Plastic Tanks IAG/USP Test Site Brazil

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2D TEM Modeling for a Hydrogeological Study in the ParanáSedimentary Basin, Brazil

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International Journal of Geosciences 2017年第5期8卷 693-710页

作者： emerson rodrigo almeida Jorge Luís Porsani Fernando Acácio Monteiro dos Santos Cassiano Antonio Bortolozo Universidade de Sã o Paulo Instituto de Astronomia Geofísica e Ciências Atmosféricas Departamento de Geofísica. Rua do Mat&atilde o Butant&atilde S&atilde o Paulo Brazil Universidade de Lisboa-IDL Lisboa Portugal

This work uses 2D TEM (Transient Electromagnetic) modeling for a hydrogeological study in the Paraná sedimentary basin. The study area is located at the northern region of the state of S?o Paulo, Brazil, where groundwater is exploited from two aquifer systems: one sedimentary, shallow, and the other crystalline, deep. The interest in applying the TEM method in this area owes to the high exploitation rates of groundwater from the crystalline aquifer system for irrigation, which is triggering considerable seismic activity locally. This aquifer system is composed of fractured basalt within the Serra Geral Formation and is about 120 m deep. Eighty-six TEM soundings were acquired at this location, but in nine cases the data did not fit the modelled curve for 1D geoelectrical models due to the geological complexity of the area. This paper shows 2D geoelectrical modeling results based on the FDTD (Finite Differences in Time Domain) method to explain the lateral resistivity variation within the geological setting. A 2D model was generated for each sounding and compared with 1D inversion models as well as with direct information from wells. The results show some vertical variations of about 10 to 30 meters on the upper interface of the basalt layer from Serra Geral Formation. They are located at approximately 60 meters from the center of the soundings. The existence of these 2D structures in the subsurface can be related to the drainage system in the study area. The presence of these structures may indicate a connection between the shallow and deep aquifer systems, acting like a conduit that may contribute to the seismic activity reported.

关键词： Transient Electromagnetic (TEM) 2D Modeling Hydrogeophysics Paraná Basin Brazil

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Depth Estimates of Buried Utility Systems Using the GPR Method: Studies at the IAG/USP Geophysics Test Site

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International Journal of Geosciences 2017年第5期8卷 726-742页

作者： Bruno Poluha Jorge Luís Porsani emerson rodrigo almeida Vinicius Rafael Neris dos Santos Scott Joseph Allen Universidade de Sã o Paulo Instituto de Astronomia Geofísica e Ciências Atmosféricas Departamento de Geofísica. Rua do Mat&atilde o S&atilde o Paulo Brazil Universidade Federal de Pernambuco. Departamento de Arqueologia. Avenida Professor Moraes Rego Cidade Universitária Pernambuco Brazil

Identifying underground utilities and predicting their depth are fundamental when it comes to civil engineering excavations, for example, to install or repair water, sewer, gas, electric systems and others. The accidental rupture of these systems can lead to unplanned repair costs, delays in completing the service, and risk injury or death of workers. One way to detect underground utilities is using the GPR-Ground Penetrating Radar geophysical method. To estimate depth, the travel time (two-way travel time) information provided by a radargram is used in conjunction with ground wave velocity, which depends on the dielectric constant of materials, where it is usually assumed to be constant for the area under investigation. This procedure provides satisfactory results in most cases. However, wrong depth estimates can result in damage to public utilities, rupturing pipes, cutting lines and so on. These cases occur mainly in areas that have a marked variation of water content and/or soil lithology, thus greater care is required to determine the depth of the targets. The present work demonstrates how the interval velocity of Dix (1955) can be applied in radargram to estimate the depth of underground utilities compared to the conventional technique of constant velocity applied to the same data set. To accomplish this, synthetic and real GPR data were used to verify the applicability of the interval velocity technique and to determine the accuracy of the depth estimates obtained. The studies were carried out at the IAG/USP test site, a controlled environment, where metallic drums are buried in known positions and depths allowing the comparison of real to estimated depths. Numerical studies were also carried out aiming to simulate the real environment with variation of dielectric constant in depth and to validate the results with real data. The results showed that the depths of the targets were estimated more accurately by means of the interval velocity technique in contrast

关键词： GPR Depth Estimation Interval Velocity Constant Velocity Urban Planning IAG/USP Test Site Brazil

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GPR Tomography as Support for an Archaeological Excavation in AripuanãIndigenous Cemetery, Amazon Region, Brazil

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International Journal of Geosciences 2017年第10期8卷 1264-1277页

作者： Jorge Luís Porsani Renato Kipnis Vinícius Rafael Neris dos Santos emerson rodrigo almeida Iris Fernandes Universidade de Sã o Paulo Instituto de Astronomia Geofísica e Ciências Atmosféricas Departamento de Geofísica S&atilde o Paulo Brazil Scientia Consultoria Científica S&atilde o Paulo Brazil

We present here a series of Ground Penetrating Radar (GPR) survey carried out in different areas of the Dardanelos 1 archaeological site in order to generate information about subsurface anomalies associated with archaeological material that could be use in decision making within the environmental licensing process of the Dardanelos Hydroelectric Power Plant, located near of the Aripuan? city, Mato Grosso State, northwest region of Brazil. GPR surveys with 200 MHz antenna were carried out in two blocks aiming to locate archaeological resources and features. The analysis of GPR 2D and 3D results allowed detecting anomalous regions characterized by hyperbolic reflections, shallow elongated continuous targets with high amplitudes, as well as sub-horizontal reflectors. Microwave tomography allowed estimating the geometry of the GPR anomalies sources. Excavations were done by archaeologists at the locations where hyperbolic anomalies were found, revealing interesting structures related to urns in the middle of a rich in organic matter consisting of black and ceramic materials up to about 1 m deep. The first sub-horizontal reflector at approximately 1 m depth is related to the base of the black soil layer rich in organic matter and the second sub-horizontal reflector between 2 and 3 m deep suggests a lithological change or may be related to presence of the water table. The continuous elongated shallow targets observed in the depth slices are related to tree roots in the middle of the archaeological strata. The GPR results guided archaeological excavations, reduced the time and costs involved in research, and contributed to the preservation of Brazilian historical heritage.

关键词： Ground Penetrating Radar (GPR) Microwave Tomography Archaeology Anthropogenic Soil Dardanelos Hydroelectric Power Plant Amazon Region Brazil

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Direct Electrochemical Determination of Glyphosate Herbicide Using a Screen-Printed Carbon Electrode Modified with Carbon Black and Niobium Nanoparticles

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Journal of Analysis and Testing 2023年第4期7卷 425-434页

作者： Julia Oliveira Fernandes Cassiano Augusto Rolim Bernardino Juliana dos Santos Fernandes Claudio Fernando Mahler Bernardo Ferreira Braz Luiz Henrique Carpenter dos Santos rodrigo JoséCorrêa Ricardo Erthal Santelli Braulio Soares Archanjo emerson Schwingel Ribeiro Fernando Henrique Cincotto Departament of Analytical Chemistry Institute of ChemistryFederal University of Rio de JaneiroRio de Janeiro 21941-909Brazil Departament of Civil Engineering COPPEFederal University of Rio de JaneiroRio de Janeiro 21941-598Brazil National Institute of Science&Technology of Bioanalytics(INCTBio) CampinasSão Paulo 13083-862Brazil Departament of Inorganic Chemistry Institute of ChemistryFederal University of Rio de JaneiroRio de Janeiro 21941-909Brazil Unesp National Institute of Alternative Technologies for DetectionToxicological Assessment and Removal of Micropollutants and Radioactives(INCT-DATREM)AraraquaraSão Paulo 14800-060Brazil National Institute of Metrology Quality and TechnologyInmetroAv.Nossa Senhora das Graças50XerémDuque de Caxias 25250-020Brazil

Glyphosate is a herbicide that has been widely used worldwide and is used in agricultural areas to control weeds and unwanted *** sensors developed from different nanomaterials have high efficiency,excellent cost-benefit,and fast analysis time for detecting traces of environmental *** study aimed to produce an electrochemical sensor with disposable screen-printed electrodes based on carbon black modified with niobium nanoparticles to determine glyphosate in aqueous *** morphology,structure and electrochemical performance of the sensor were characterized by scanning electron microscopy,energy-dispersive X-ray spectroscopy,X-ray diffraction and cyclic *** pulse voltammetry in BR buffer solution at pH 5.0 allowed the generation of a method to quantify glyphosate concentration in a linear range of 5.90-172.30μmol/L(1.00-29.13μg/mL),with a limit of detection calculated at 3.07μmol/L(0.52μg/mL).The method efficiently quantified glyphosate in real water samples and showed no interference from K^(+),Na^(+),Ca^(2+),Mg^(2+)ions or thiamethoxam,imidacloprid and carbendazim pesticides.

关键词： Glyphosate Electrochemical sensor Carbon black Niobium nanoparticles

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Downstaging and resection after neoadjuvant therapy for fibrolamellar hepatocellular carcinoma

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World Journal of Gastrointestinal Surgery 2014年第6期6卷 107-111页

作者： Gilton Marques Fonseca Antonio Drauzio Varella Fabricio Ferreira Coelho emerson Shigueaki Abe rodrigo Blanco Dumarco Paulo Herman Digestive Surgery Division Department of Gastroenterology University of So Paulo School of Medicine Avenida Doutor Enéas de Carvalho Aguiar 255 Instituto Central 05403-900 So Paulo Brazil Clinical Oncologist Hospital Sírio-Libanês 01308-050 So Paulo Brazil

Fibrolamellar hepatocellular carcinoma(FLHCC) is a rare malignant liver neoplasm, commonly observed in adolescents and young adults of both genders. The disease is more common in Caucasians and in patients without a prior history of liver disease. The best treat-ment option is a surgical resection associated with liver hilum lymph node dissection. However, there is no established systemic drug treatment for patients with locally advanced or metastatic disease. We report on a patient with advanced FLHCC, initially considered un-resectable due to invasion of the right and the middle hepatic veins and circumferential involvement of the left hepatic vein. Following the treatment with gem-citabine-oxaliplatin systemic chemotherapy, the patient exhibited a significant tumor reduction. As a result, a complete resection was performed with an extended right hepatectomy associated with a partial resection of the inferior vena cava, a wedge resection in segment 2, and lymphadenectomy of the hepatic hilum. The case was unusual due to the significant tumor downstaging with gemcitabine-oxaliplatin, potentially enabling cura-tive resection. More studies are needed to confirm the efficacy of the systemic drug treatment for FLHCC.

关键词： Chemotherapy Gemcitabine Oxaliplatin Hepatectomy Hepatic veins Fibrolamellar hepatocellular carcinoma

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