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Elimination of LWD (Logging While Drilling) Tool modes Using Seismoelectric Data

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Communications in Computational Physics 2010年第1期7卷 47-63页

作者： Xin zhan zhenya zhu Shihong Chi m.nafi tok.oz Earth Resources Laboratory Massachusetts Institute of TechnologyBuilding 54-181577 Massachusetts AveCambridgeMA 02142USA Petrophysics ConocoPhillips600 North Dairy AshfordHoustonTX 77252USA

Borehole acoustic logging-while-drilling (LWD) for formation evaluationhas become an indispensable part of hydrocarbon reservoir assessment [F. Citt ´a, C. Rus-sell, R. Deady and D. Hinz, The Leading Edge, 23 (2004), pp. 566-573]. However,the detection of acoustic formation arrivals over tool mode contamination has beena challenging problem in acoustic LWD technology. In this paper we propose a newmethod for separating tool waves from formation acoustic waves in acoustic *** method is to measure the seismoelectric signal excited by the LWD acoustic *** LWD tool waves which propagate along the rigid tool rim can not excite any elec-tric signal. This is due to the effectively grounding of the drill string during the LWDprocess makes it impossible to accumulate any excess charge at the conductive tool —borehole fluid interface. Therefore, there should be no contribution by the tool modesto the recorded seismoelectric signals. To theoretically understand the seismoelectricconversion in the LWD geometry, we calculate the synthetic waveforms for the multi-pole LWD seismoelectric signals based on Pride’s theory [S. R. Pride, Phys. Rev. B, 50(1994), pp. 15678-15696]. The synthetic waveforms for the electric field induced by theLWD-acoustic-wave along the borehole wall demonstrate the absence of the tool *** also designed the laboratory experiments to collect simulated LWD monopole anddipole acoustic and seismoelectric signals in a borehole in sandstone. By analyzing thespectrum of acoustic and electric signals, we can detect and filter out the differencebetween the two signals, which are the mainly tool modes and noise.

关键词： Logging While Drilling acoustoelectric logging multipole LWD seismoelectric sig-nal laboratory experiment numerical simulation

Theoretical and Experimental Studies of Seismoelectric Conversions in Boreholes

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Communications in Computational Physics 2008年第1期3卷 109-120页

作者： zhenya zhu Shihong Chi Xin zhan m.nafi tok.¨oz Earth Resources Laboratory Massachusetts Institute of Technology42 Carleton St.CambridgeMA 02142USA Petrophysics ConocoPhillips600 NorthDairy AshfordHoustonTX 77252USA.

We present theoretical and experimental studies on the effects of formationproperties on seismoelectric conversions in fluid-filled boreholes. First, we derive thetheoretical formulations for seismoelectric responses for an acoustic source in a ***, we compute the electric fields in boreholes penetrating formations withdifferent permeability and porosity, and then we analyze the sensitivity of the convertedelectric fields to formation permeability and porosity. We also describe the laboratoryresults of the seismoelectric and seismomagnetic fields induced by an acousticsource in borehole models to confirm our theoretical and numerical developmentsqualitatively. We use a piezoelectric transducer to generate acoustic waves and a pointelectrode to receive the localized seismoelectric fields in layered boreholes and theelectric component of electromagnetic waves in a fractured borehole model. Numericalresults show that the magnitude ratio of the converted electric wave to the acousticpressure increases with the porosity and permeability increases in both fast and slowformations. Furthermore, the converted electric signal is sensitive to the formationpermeability for the same source frequency and formation porosity. Our experimentsvalidate our theoretical results qualitatively. An acoustic wave at a fracture intersectinga borehole induces a radiating electromagnetic wave.

关键词： Seismoelectric conversions borehole measurements laboratory experiments acoustic waves borehole models.

Depth determination of the moho interface beneath the Tibetan plateau and other areas of China

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Earthquake Science 2012年第5期25卷 415-431页

作者： Youshun Sun Diming Yu m nafi tok.z F Dale morgan Xiyu Wang Jinrong Su Jun Liu State Key Laboratory of Geodesy and Earth's Dynamics Institute of Geodesy and GeophysicsChinese Academy of Sciences Department of Earth Atmospheric and Planetary SciencesMassachusetts Institute of Technology Earthquake Administration of Sichuan Province School of Civil Engineering and Architecture Wuhan University of Technology

We apply the adaptive moving window method of Sun et al. to the most recent catalog data and the data recorded by portable stations to construct the velocity structure of the crust and upper mantle, and to determine the depth of the moho interface beneath the Tibetan plateau and other areas of China. We first select 2 600 locations in the study region with 1° intervals, then at each location invert for a five-layer 1-D P-wave velocity model from the surface down to the uppermost mantle by performing a monte Carlo random search. The moho depth at each location is then determined, and the moho interface beneath the study region is obtained through proper interpolation with certain smoothing. Compared to depths obtained by previous studies, our results show more accurate moho depths in the Tibetan plateau, Tianshan region and other areas of the study region.

关键词： moho depth moho interface Tibetan plateau

Vegetative Compatibility and Virulence Diversity of Verticillium dahliae from Okra (Abelmoschus esculentus) Plantations in Turkey and Evaluation of Okra Landraces for Resistance to V. dahliae

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Phyton-International Journal of Experimental Botany 2020年第2期89卷 303-314页

作者： Fatih m.tok.Sibel Dervis Halit Yetisir Hatay mustafa Kemal University Department of Plant ProtectionFaculty of AgricultureAntakyaHatay31034Turkey mardin Artuklu University Vocational School of KızıltepeDepartment of Plant and Animal ProductionMardin47000Turkey Erciyes University Department of HorticultureFaculty of AgricultureKayseri38225Turkey

Forty-four *** isolates were collected from symptomatic vascular tissues of okra plants each from a different field in eight provinces located in the eastern mediterranean and western Anatolia regions of Turkey during ***-nonutilizing(nit)mutants of *** from okra were used to determine heterokaryosis and genetic relatedness among *** isolates from okra plants were grouped into two vegetative compatibility groups(VCGs)(1 and 2)and three subgroups as 1A(13.6%,6/44),2A(20.5%,9/44)and 2B(65.9%,29/44)according to international *** tests were performed on a susceptible local okra(***)landrace in greenhouse *** isolates from VCG1A and VCG2B induced defoliation(D)and partial defoliation(PD)symptoms,*** isolates from VCG2A gave rise to typical leaf chlorosis symptoms without *** obtained data showed that the virulence level of *** isolates from okra was related to their VCG *** okra landraces from diverse geographical origins were screened for resistance to VCG2B and VCG1A of *** results indicated that all landraces were more susceptible to highly virulent VCG1A-D pathotype displaying D or PD symptoms depending on their susceptibility levels with a mean disease severity index of 3.52 than to less virulent VCG2B-PD pathotype of *** displaying PD and ND symptoms with a mean disease severity index of *** differences were observed among the landraces;however,none of them exhibited a level of *** landraces;Çorum,Hatay Has and Sanlıurfa displayed the lowest level of susceptibility or little tolerance to both D and PD ***2B of PD was prevailing in the surveyed areas and VCG1A of D was the most virulent of the VCGs *** of resistant genotypes to Turkish okra germplasm from different sources and breeding new resistant okra cultivars are critical for the sustainability of okra production.

关键词： Landraces malvaceae nit mutants pathotypes VCGs defoliating wilt

Crustal and uppermost mantle structure of Caucasus and surrounding regions

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Earthquake Science 2012年第5期25卷 505-515页

作者： Youshun Sun m nafi tok.z Randolph J martin mary Krasovec Diming Yu Qingyun Liu Jun Liu State Key Laboratory of Geodesy and Earth's Dynamics Institute of Geodesy and GeophysicsChinese Academy of Sciences Department of Earth Atmospheric and Planetary SciencesMassachusetts Institute of Technology New England Research Inc.White River Jct. School of Civil Engineering and Architecture Wuhan University of Technology

A 3-D P-wave velocity model is developed for the crust and uppermost mantle of Caucasus and the surrounding area by applying the tomographic method of zhao et al. using 300 000 high-quality P-wave first arrivals from 43 000 events between 1964 and 2005. This tomographic method can accommodate velocity discontinuities such as the moho in addition to smooth velocity variations. The spatial resolution is 1°× 1° in the horizontal direction and 10 km in depth. The velocity images of the upper crust correspond well with the surface geology. Beneath the southern Caucasus high velocity anomalies are found in the middle crust and low velocity anomalies are found in the uppermost mantle. Relatively low Pn velocities are located under the Lesser Caucasus, eastern Turkey, and northern Iran. Higher Pn velocities occur under the eastern portion of the Black Sea and the southern Caspian Sea, and also extend into the eastern edge of Azerbaijan. Tomographic model significantly reduces the travel-time residuals.

关键词： Caucasus region crustal structure Pn velocity 3-D tomography

Petrographic of Northwestern Sudan

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Journal of China University of Geosciences 2003年第2期14卷 137-143页

作者： nafi Abdullatif O m m Faculty of Earth Resources China University of Geosciences Wuhan 430074 Department of Geology Faculty of Science University of Khartoum Sudan

The sedimentology of the Northwestern Sudan consists of lower, middle and upper cycles. The lower and upper cycles are composed of intercalated fluvial and shallow marine facies, whereas the middle cycle consists entirely of fluvial and glaciofluvial facies. The petrographic analysis shows that the lower and upper cycles consist of quartz and lithic arenite sandstones, whereas the middle cycle consists of arkosic and lithic arenite sandstones. The lower and upper cycle sandstones reflect derivation mainly from recycled orogens with minor contribution from craton interior provenances. However, the middle cycle sandstones indicate derivation from basement uplift, transitional and mainly recycled orogens provenances.

关键词： glaciofluvial recycled orogen marine facies.

Transfer of single dose of intravitreal injection of ranibizumab and bevacizumab into milk of sheep

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International Journal of Ophthalmology(English edition) 2017年第7期10卷 1069-1075页

作者： Tugba Cakmak Argun Ozlem Yalcin tok.Levent tok.Gulsen Yilmaz Fatma meric Yilmaz Alime Gunes mehmet Argun Osman Butuner Department of Ophthalmology Hatay Dortyol State Hospital Faculty of medicine Ophthalmology Suleyman Demirel University ministry of Health Ankara HospitalBiochemistry Biochemistry Department Faculty of MedicineYildirim Beyazit University The management of Veterinary Service

AIm： To investigate whether single-dose intravitreal injections of bevacizumab and ranibizumab transfer into milk. mETHODS： This study included lactating 12 sheep and a single 3-month old suckling lamb of each sheep. Two groups consisting of 6 sheep and their lambs were constituted; the ranibizumab group and the bevacizumab group before the administration of intravitreal injections, blood and milk samples were obtained from all sheep and, following the injections, blood and milk samples of all sheep and blood samples of all lambs were collected at regular time points. Serum and milk concentrations of bevacizumab and ranibizumab were measured using an enzyme-linked immunosorbent assay（ELISA） kit. The limit of determination was 0.9 ng/m L for bevacizumab and 0.62 ng/m L for ***： At 6h after intravitreal injections, bevacizumab concentration was above the limit of determination in the blood of all sheep. At 3wk, when the study was terminated, bevacizumab concentrations were high in 4 sheep. Even though bevacizumab concentrations in milk showed fluctuations, the drug transferred into the milk of all sheep at detectable concentrations. Ranibizumab drug concentrations in the blood and milk of sheep and those in the blood of lambs were below the limit of determination by the ELISA ***： This sheep model study demonstrate that intravitreal injection of ranibizumab, which did not transfer into the milk of sheep and suckling lambs, is safer than bevacizumab during lactation period.

关键词： bevacizumab ranibizumab lactation milk vascular endothelial growth factor

modernization, Globalization and Europeanization in the Cities of Anatolia, Turkey in Post 1980s

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International Relations and Diplomacy 2016年第10期4卷 617-629页

作者： m. Evren tok Hamad Bin Khalifa University Doha Qatar

This study will portray the socio-economic and cultural bases of the alternative modernity claims of three Anatolian cities： Kayseri, Gaziantep and Eskisehir. The intention is to build a picture of the local socio-economic and cultural capacities of these cities and compare them. This comparative analysis will also involve a temporal dimension in the differentiation between the pre-1980s and post-1980s periods. It is hoped that this will offer a better perspective on the different starting points of the cities that resulted from historical levels of state involvement, which in turn produced variation in the formation of industrial and manufacturing capacities. Various practices of market based policies, which influenced the socio-economic conditions in these cities, will be presented to help us conceive of the differential impacts of these policies. Similarly, by looking at export capacities and labor market indicators in each city, we will have a more complete picture of the basis for claims of success. Two external processes, globalization and Europeanization and the changes and transformations they elicited, will also be discussed as additional and significant components in these cities＇ claims to success.

关键词： local economic development Anatolian tigers Turkey globalization Europeanization

Electrochemical,spectroscopic,and molecular docking studies of the interaction between the anti-retroviral drug indinavir and dsDNA

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Journal of Pharmaceutical Analysis 2020年第5期10卷 473-481页

作者： Fariba mollarasouli Burcu Dogan-Topal mehmet Gokhan Caglayan Tugba Taskin-tok.Sibel A.Ozkan Ankara University Department of Analytical Chemistry06560AnkaraTurkey Department of Chemistry Yasouj UniversityYasouj75918-74831Iran Department of Chemistry Gaziantep University27310GaziantepTurkey Institute of Health Sciences Department of Bioinformatics and Computational BiologyGaziantep University27310GaziantepTurkey

In this study,an electrochemical DNA biosensor was developed using a straightforward methodology to investigate the interaction of indinavir with calf thymus double-stranded deoxyribonucleic acid(ctdsDNA)for the first *** decrease in the oxidation signals of deoxyguanosine(dGuo)and deoxyadenosine(dAdo),measured by differential pulse voltammetry,upon incubation with different concentrations of indinavir can be attributed to the binding mode of indinavir to *** currents of the dGuo and dAdo peaks decreased linearly with the concentration of indinavir in the range of 1.0 e10.0 mg/*** limit of detection and limit of quantification for indinavir were 0.29 and 0.98 mg/mL,respectively,based on the dGuo signal,and 0.23 and 0.78 mg/mL,respectively,based on the dAdo *** gain further insights into the interaction mechanism between indinavir and ct-dsDNA,spectroscopic measurements and molecular docking simulations were *** binding constant(Kb)between indinavir and ct-dsDNA was calculated to be 1.64108 m1,based on spectrofluorometric *** obtained results can offer insights into the inhibitory activity of indinavir,which could help to broaden its *** is,indinavir can be used to inhibit other mechanisms and/or hallmarks of viral diseases.

关键词： Glassy carbon electrode Calf thymus double-stranded deoxyribonucleic acid(ct-dsDNA) Biosensor Fluorescence molecular docking