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Estimating rock properties using sound signal dominant frequencies during diamond core drilling operations

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journal of Rock Mechanics and Geotechnical Engineering 2019年第4期11卷 850-859页

作者： ch.Vijaya Kumar Harsha Vardhan ch.S.n.Murthy n.C.Karmakar Department of Mining Engineering National Institute of Technology KarnatakaSurathkalIndia Indian Institute of Technology (BHU) VaranasiIndia

In many engineering applications such as mining,geotechnical and petroleum industries,drilling operation is widely *** drilling operation produces sound by-product,which could be helpful for preliminary estimation of the rock ***,determination of rock properties is very difficult by the conventional methods in terms of high accuracy,and thus it is expensive and *** this context,a new technique was developed based on the estimation of rock properties using dominant frequencies from sound pressure level generated during diamond core drilling ***,sound pressure level was recorded and sound signals of these sound frequencies were analyzed using fast Fourier transform (FFT).Rock drilling experiments were performed on five different types of rock samples using computer numerical control (CnC) drilling machine BMV 45 *** simple linear regression analysis,mathematical equations were developed for various rock properties,*** compressive strength,Brazilian tensile strength,density,and dominant frequencies of sound pressure *** developed models can be utilized at early stage of design to predict rock properties.

关键词： Rock properties Sound pressure level Fast Fourier transform (FFT) Sound signal Core drilling Dominant frequencies

Human Toxicosis Caused by Moldy Rice Contaminated with Fusarium and T-2 Toxin

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Biomedical and Environmental Sciences 1993年第1期6卷 65-70页

作者： z G Wang j n Feng z Tong zhejiang Institute of Food Safety Control and Inspection Hangzhou China.

This is the first report on human toxicosis in china caused by moldy rice contaminated with Fusarium and T-2 toxin due to heavy rainfall during rice harvest season. One hundred and sixty-five persons ate the moldy rice and ninety-seven persons fall ill of food poisoning. The incidence was 58.8% and latent period was 10-30 min. The chief symptoms were nausea, dizziness, vomiting, chills, abdominal distension, abdominal pain, thoracic stuffiness and diarrhea. The fungi isolated from the moldy rice were predominantly Fusarium heterosporum (F. heterosporum) and F. graminearum. T-2 toxin was found in these moldy rice and the highest level was 420 ppb. The chief causative agent of intoxication was T-2 toxin.

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The Structure of Cool Flame Fronts of Pentane, Iso-Pentane and Their Mixture

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journal of Thermal Science 2000年第4期9卷 365-370页

作者： z.A.Mansurov ch.K.Westbrook 等 Al－FarabiKazakhStatenationalUniversity KarasaiBatryStr.95Akmaty480012kazakhstan UniversityofCaliforniaLawrenceLivermorenationalLaboratory

An experimental study of the combustion of two isomers of n-pentane and iso-pentane in laminar cool flames has been carried out. Three flames were studied, one with n-pentane, the second with iso-pentane, and the third with an equimolar mixture of the two isomers. Particular attention has been given to the low temperature region ahead of the hot region of the flame and the cool flame chemistry occurring there. A unique experimental facility has been used to provide access to this cool flame region. Comparisons are made of the structures of the three flames, with particular attention on the different intermediate species produced and the correlations between the fuel molecule structure and the specific intermediates produced.

关键词： hydrocarbon cool names concentration profile.

Geochemical studies of hybrid granite from Madugulapalli area, Eastern Dharwar Craton, Southern India: Implications for crustal mixing

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Acta Geochimica 2023年第1期42卷 9-23页

作者： nagamma j Ratnakar j Ajay kumar A Ashok ch State Mines and Geology Department 508001 NalgondaIndia Department of Geology Osmania University500007 HyderabadIndia CSIR-national Geophysical Research Institute 500007 UppalHyderabadIndia

Magma produced by melting of continental crust and mantle at the Archean-Proterozoic boundary are compositionally variable and chemical compositions provide evidence for the mixing of two sources. Understanding the composition of hybrid magma is essential for determining the comparative infl uence of crust and mantle sources during orogenesis. The hybrid granites are less documented in Indian cratons, especially less in Dharwar Craton. Here we present petrographic and whole-rock geochemical data of Madgulapalli granitic rocks situated in the nE part of the Eastern Dharwar Craton(EDC), to elucidate their petrogenesis and role in crust formation. The Madugulapalli granites(MPG) are composed chiefl y of plagioclase, quartz, and alkali feldspar with associated biotite showing alteration and inter-granular textures. Geochemically, they are metaluminous to peraluminous in nature with calc-alkaline hybrid granite. The hybrid granites exhibit both negative and positive europium anomalies;the lower Rb/Sr, Rb, Sr, and higher Sr/Y,(Dy/Yb)n ratios suggest that the interaction of older rocks with residual garnet source melted at high pressures. We hypothesize that hybrid granites are formed by interaction(e.g., metasomatism, mingling, or mixing) between parental magmas and pre-existing rocks with the infl uence of sanukitoid melts(heat source) in a subduction environment. The genesis of the hybrid granites demonstrates the mixing coupled with diff erentiation in the petrogeny’s residue system in a syn-collision setting followed by continental crust stability in EDC during the neoarchean period.

关键词： Madugulapalli granite Hybrid granite Crustal mixing Subduction

nonstationary fuzzy forecasting of wind and wave climate in very long-term scales

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journal of Ocean Engineering and Science 2018年第2期3卷 144-155页

作者： ch.n.Stefanakos E.Vanem SInTEF Ocean Department of Energy and TransportPostboks 4762 TorgardenTrondheim NO-7465Norway DnV GL Group Technology and ResearchP.O Box 3001322HøvikNorway

Global climate change may have serious impact on human activities in coastal and other *** change may affect the degree of storminess and,hence,change the wind-driven ocean wave *** may affect the risks associated with maritime activities such as shipping and offshore oil and ***,there is a recognized need to understand better how climate change will affect such ***,such understanding comes from future projections of the wind and wave climate from numerical climate models and from the stochastic modelling of such *** work investigates the applicability of a recently proposed nonstationary fuzzy modelling to wind and wave climatic *** to this,fuzzy inference models(FIS)are coupled with nonstationary time series modelling,providing us with less biased climatic *** long-term datasets for an area in the north Atlantic Ocean are used in the present study,namely nORA10(57 years)and ExWaCli(30 years in the present and 30 years in the future).Two distinct experiments have been performed to simulate future values of the time series in a climatic *** assessment of the simulations by means of the actual values kept for comparison purposes gives very good results.

关键词： Fuzzy time series Wind and wave data Forecasting nonstationary Ocean wind and wave climate

Deep-water cirripedes colonizing dead shells of the cephalopod nautilus macromphalus from new Caledonian waters

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Integrative zoology 2019年第6期14卷 561-575页

作者： john BUCKERIDGE TomášKOČÍ ján SchLÖGL Adam TOMAŠOVÝch Martina KOČOVÁVESELSKÁ Earth&Oceanic Systems Group RMIT UniversityMelbourneVictoriaAustralia Ivančická581 PragueCzech Republic and Palaeontological DepartmentNatural History MuseumNational MuseumPragueCzech Republic Department of Geology and Paleontology Comenius University in BratislavaBratislavaSlovakia Institute of Earth Sciences Slovak Academy of SciencesBratislavaSlovakia Department of Paleobiology and Paleoecology Institute of Geology of the Czech Academy of SciencesPragueCzech Republic Museums Victoria MelbourneVictoriaAustralia Faculty of Science Charles University in PraguePragueCzech Republic

Fossil cephalopods are frequently encrusted by epibionts;however,determining whether encrustation occurred prior to or post-mortem to the host,and whether the final environment of deposition corresponds to the habitat of encrustation is *** present paper describes cirripede epibionts,their calcareous bases and their attachment scars on 6 post-mortem shells of nautilus macromphalus,collected from deep water off new Cale*** cirripedes have left both cemented calcareous bases of Hexelasma and scars associated with bioerosion and discoloration produced by verrucomorph *** cirripedes included a Metaverruca recta,with articulated opercular plates and organic tissue(on a shell that had been exposed on the sea floor for at least 150 years),and specimens of Hexelasma velutinum,one of which was partly attached to an internal surface of a *** disposition of verrucomorphs indicates that most nautilus shells were colonized post-mortem rather than during a floating ***,as cirripedes are known to have colonized living nautilus,some Hexelasma,preserved only as calcareous eroded bases,may represent specimens that settled on a living *** degree of bioerosion and discoloration induced by verrucomorph barnacles varies according to the surface preservation of nautilus shells,with deeper and discolored traces preserved on old and degraded *** made by verrucomorphs described here are ellipsoidal and a new ichnotaxon,Anellusichnus ellipticus,is proposed to accommodate ***,verrucomorphs and other cirripede taxa with membranous bases that were attached to pristine shells may not leave any substantial scars,and,thus,will be difficult to detect in the fossil record.

关键词： Anellusichnus ellipticus isp.nov cirripedes epibionts Hexelasma velutinum Metaverruca recta

Effect of Al_(2)O_(3)on the Mechanical Properties of(B_(4)C+Al_(2)O_(3))/Al neutron Absorbing Materials

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1411-1420页

作者： j.X.Cai B.M.Shi n.Li Y.Liu z.G.zhang Y.n.zan Q.z.Wang B.L.Xiao z.Y.Ma Shi‑changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key Laboratory of nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China nuclear Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.Ltd.Beijing 100840China Department of Materials Science School of Mechanical EngineeringShenyang UniversityShenyang 110044China

B_(4)C/Al composites are widely utilized as neutron absorbing materials for the storage and transportation of spent nuclear *** order to improve the high-temperature mechanical properties of B_(4)C/Al composites,in-situ nano-Al_(2)O_(3)was introduced utilizing oxide on Al powder *** this study,the Al_(2)O_(3)content was adjusted by utilizing spheroid Al powder with varying diameters,thereby investigating the impact of Al_(2)O_(3)content on the tensile properties of(B_(4)C+Al_(2)O_(3))/Al *** was found that the pinning effect of Al_(2)O_(3)on the grain boundaries could hinder the recovery of dislocations and lead to dislocation accumulation at high *** the result,with the increase in Al_(2)O_(3)content and the decrease in grain size,the high-temperature strength of the composites increased *** finest Al powder used in this investigation had a diameter of 1.4μm,whereas the resultant composite exhibited a maximum strength of 251 MPa at room temperature and 133 MPa at 350℃,surpassing that of traditional B_(4)C/Al composites.

关键词： Al matrix composites neutron absorbing materials (B_(4)C+Al_(2)O_(3))/Al composites High-temperature strength

EVOLUTIOn OF THE ELECTROchEMICAL chARACTERISTICS DURInG PITTInG CORROSIOn OF PURE ALUMInUM In SODIUM chLORIDE SOLUTIOn

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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 525-532页

作者： z. zhang C. Cai F.H. Cao z.n. Gao j.Q. zhang C.n. Cao Department of chemistry Zhejiang University Hangzhou 310027 China Department of chemistry Ningxia University Yinchuan 750021 China State Key Laboratory for Corrosion and Protection of Metals Institute of Metal Research The Chinese

The corrosion behavior of pure aluminum in neutral 3.0% （mass fraction） sodium chloride （na-Cl） solution has been studied using electrochemical impedance spectroscopy （EIS） measurement in conjunction with the scanning electron microscopy （SEM） technique. EIS information on the evolution of pitting corrosion over a period of 15 days has been obtained and analyzed with equivalent circuit technique. The results shown that, during the ensemble constant immersion time, two time constants involved, the high frequency one originated from the protective layer on the corroding surface while the low frequenO, one from the diffusion process or the corrosion reaction and so on. And there existed a period for oxide film to growth and thickening prior to the of the attacking of chloride ions to the substrate. Meanwhile, good relationship between EIS and the material corrosion type/severity has been obtained, which has been interpreted according to the characteristics of corrosion process such as auto acceleration of pitting corrosion and the protection of local anodic reaction to the area around them.

关键词： pure aluminum pitting corrosion electrochemical impedance spectroscopy pit-rnorphology

Medium Range Prediction of Summer Monsoon Activities over India vis-a-vis Their Correspondence with the Observational Features

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Advances in Atmospheric Sciences 1999年第1期16卷 135-148页

作者： Swati Basu K. j. Ramesh z. n. Begum national Centre for Medium Range Weather Forecasting (nCMRWF) Department of Science and Technology New Delhi India

A detailed examination on various aspects of the southwest monsoon over the Indian subcontinent using analyses and forecasts of the nCMRWF global data assimilation and forecast system for the years 1994 and 1996 is carried out in this study. Objective procedures developed by Ramesh et al. (1996) based on the monsoon 1995 data are employed in the present work. It is found that all the deterministic features of the summer monsoon viz., the onset, its advancement, stagnation/revival and the withdrawal, can reasonably by prognosticated after employing the objective methodologies and monitoring daily variations of certain derived quantities from the large scale analyses and forecasts. Further, a good correspondence of the observed large scale/synoptic scale circulation features and the observed rainfall etc. with the deterministic characteristics of the summer monsoon show a good prospect for real time prognosis of the important summer monsoon activities over the Indian subcontinent.

关键词： Summer monsoon Objective procedure Onset Advancement Withdrawal