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Geochemical evidences of trace metal anomalies for finding hydrocarbon microseepage in the petroliferous regions of the Tatipaka and Pasarlapudi areas of Krishna Godavari Basin,India

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Petroleum Science 2013年第1期10卷 19-29页

作者： Rasheed m A Lakshmi m rao P L S Kalpana m S Dayal A m Patil D J microbiology Laboratory Petroleum Geochemistry Group National Geophysical Research Institute (Council of Scientific and Industrial Research)

The long-term seepage of hydrocarbons, either as macroseepage or microseepage, can set up near-surface oxidation reduction zones that favor the development of a diverse array of chemical and mineralogical changes. The bacterial oxidation of light hydrocarbons can directly or indirectly bring about significant changes in the values of pH and Eh of the surrounding environment, thereby also changing the stability fields of the different mineral species present in that environment. The paper reports the role of hydrocarbon microseepage in surface alterations of trace metal concentrations. In this study trace metal alterations were mapped that appear to be associated with hydrocarbon microseepages in the oil/ gas fields. A total of 50 soil samples were collected near oil and gas fields of the Tatipaka and Pasarlapudi areas of the Krishna Godavari Basin, Andhra Pradesh. The soil samples were collected from a depth of 2-2.5 m. The paper reports the chemical alterations associated with trace metals in soils that are related to hydrocarbon microseepages above some of the major oil and gas fields of this petroliferous region. Trace metals, such as scandium （Sc）, vanadium （V）, chromium （Cr）, cobalt （Co）, nickel （ni）, copper （Cu）, zinc （Zn）, barium （Ba） and strontium （Sr）, in soil samples were analyzed using inductively coupled plasma- mass spectrometry （ICP-mS）. The concentrations of Sc （8 to 40 mg/kg）, V （197 to 489 mg/kg）, Cr （106 to 287 mg/kg）, Co （31 to 52 mg/kg）, ni （65 to 110 mg/kg）, Cu （88 to 131 mg/kg）, Zn （88 to 471 mg/kg）, Ba （263 to 3,091 mg/kg） and Sr （119 to 218 mg/kg） were obtained. It was observed that the concentrations of trace elements were tremendously increased when they were compared with their normal concentrations in soils. The analysis of adsorbed soil gas showed the presence of high concentrations of YC2＋（C2H6, C3H8 and n-C4H10） ranging from 7 to 222 μg/kg respectively. Integrated studies of trace elements over adsorbed light gaseous hydrocarbons （2C2

关键词： Hydrocarbons microseepage trace metal alterations adsorbed soil gas Krishna Godavari Basin

machine Learning for many-Body Localization Transition

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Chinese Physics Letters 2020年第8期37卷 12-18页

作者： Wen-Jia rao School of Science Hangzhou Dianzi UniversityHangzhou 310027China

We employ the methods of machine learning to study the many-body localization(mBL)transition in a 1D random spin *** using the raw energy spectrum without pre-processing as training data,it is shown that the mBL transition point is correctly predicted by the *** structure of the neural network reveals the nature of this dynamical phase transition that involves all energy levels,while the bandwidth of the spectrum and nearest level spacing are the two dominant patterns and the latter stands out to classify *** further use a comparative unsupervised learning method,i.e.,principal component analysis,to confirm these results.

关键词： spectrum transition Transition

The Characterizations of Hyper-Star Graphs Induced by Linearly Separable Boolean Functions

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Chinese Journal of Electronics 2018年第1期27卷 19-25页

作者： rao Yanyi ZHAnG Xianda Department of Automation Tsinghua University

A hyper-star is a graph consisting of the union of some hypercubes with at least one common vertex. The graph induced by a linearly separable Boolean function is a hyper-star. We obtain some properties of hyper-stars and give a decomposition algorithm of a hyperstar. We give a determination condition for a *** determination condition yields an algorithm of constructing all hyper-stars of n vertices in time O（n3）.

关键词： Boolean function Hypercube Hyper-star Algorithm

Blind Equalization Using Coordinate mapping for 4-PAm and 16-QAm Signals

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Chinese Journal of Electronics 2014年第1期23卷 124-128页

作者： rao Wei nanchang Institute of Technology

It is well known that the famous Constant modulus algorithm(CmA) presents a large steady-state mean square error(mSE) for nonconstant modulus signals. In this paper a coordinate mapping approach for a4-PAm nonconstant modulus signal is described which can change the signal to an Offset QPSK(OQPSK) constant modulus signal. And a new algorithm based on this approach is proposed which is also suitable for a 16-QAm signal. For the 4-PAm and 16-QAm nonconstant modulus signals the proposed algorithm can achieve a zero steadystate mSE in a noiseless environment but CmA *** analysis and simulations results demonstrate the high performance of the proposed algorithm.

关键词： Blind equalization Constant modulus algorithm Coordinate mapping

Investigations on Heat Transfer Enhancement in Pool Boiling with Water-CuO nano-Fluids

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Journal of Thermal Science 2012年第2期21卷 179-183页

作者： Ramakrishna n. Hegde Dr. Shrikantha S. rao R. P. Reddy Research Scholar National Institute of Technology Surathkal/ Department of Mechanical Engineering M S R I T Bangalore 560054 Assistant Professor Department of Mechanical Engineering National Institute of Technology Surathkal Reva Institute of Technology Yelahanka Bangalore 560064

The main focus of the present work is to investigate Critical Heat Flux (CHF) enhancement using CuO nanofluid relative to CHF of pure water. To estimate the effect of nanoparticles on the CHF, pool boiling CHF values were measured for various volume concentrations of CuO nanofluid and compared with pure water. CHF enhancement of 130% was recorded at 0.2 % by volume of CuO nano-fluids. Surface roughness of the heater surface exposed to three measured heating cycles indicated surface modifications at different volume concentrations of nanofluid. SEm image of the heater surface revealed porous layer build up, which is thought to be the reason for CHF enhancement.

关键词： nanofluid pool boiling CHF enhancement nano-particle.

Petrology,genesis and geodynamic implication of the mesoproterozoic-Late Cretaceous Timmasamudram kimberlite cluster,Wajrakarur field,Eastern Dharwar Craton,southern India

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Geoscience Frontiers 2017年第3期8卷 541-553页

作者： Ashish Dongre n.V.Chalapathi rao K.S.Viljoen B.Lehmann Department of Geology University of Johannesburg Department of Geology Centre of Advanced StudyBanaras Hindu University mineral Resources Technical University of Clausthal

new mineralogical and bulk-rock geochemical data for the recently recognised mesoproterozoic （ca. 1100 ma） and late Cretaceous （ca. 90 ma） kimberlites in the Timmasamudram cluster （TKC） of the Wajrakarur kimberlite field （WKF）, Eastern Dbarwar Craton, southern India, are presented. On the basis of groundmass mineral chemistry （phlogopite, spinel, perovskite and clinopyroxene）, bulk-rock chem- istry （SiO2, K20, low TiO2, Ba/nb and La/Sm）, and perovskite nd isotopic compositions, the TI（-1 （mac- rocrystic variety） and TI（-4 （macrocrystic variety） kimberlites in this cluster are here classified as orangeites （i.e. Group II kimberlites）, with geochemical characteristics that are very similar to orangeites previously described from the Bastar Craton in central India, as well as the Kaapvaal Craton in South Africa. The remaining kimberlites （e.g., TK-2, TK-3 and the TK-1 microcrystic variant）, are more similar to other 1100 ma, Group l-type kimberlites of the Eastern Dharwar Craton, as well as the typical Group I kimberlites of the Kaapvaal Craton. Through the application of geochemical modelling, based on pub- lished carbonated peridotite/melt trace element partition coefficients, we show that the generation of the TI（C kimberlites and the orangeites results from low degrees of partial melting of a metasomatised, carbonated peridotite. Depleted mantle （TDm） nd perovskite model ages of the 1100 ma Timmasamudram kimberlites show that the metasomatic enrichment of their source regions are broadly similar to that of the meso- proterozoic kimberlites of the EDC. The younger, late Cretaceous （ca. 90 ma） TI（-1 （macrocrystic variant） and TK-4 kimberlites, as well as the orangeites from the 8astar Craton, share similar nd model ages of 1100 ma, consistent with a similarity in the timing of source enrichment during the amalgamation of Rodinia supercontinent. The presence of late Cretaceous diamondiferous orangeite activity, presumably related to the location of the marion hotspot

关键词： Kimberlite Orangeite Diamond Timmasamudram Wajrakarur India

Hepatoprotective and antioxidant capacity of melochia corchorifolia extracts

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Asian Pacific Journal of Tropical medicine 2013年第7期6卷 537-543页

作者： B Ganga rao Y Venkateswara rao T mallikarjuna rao A.U College of Pharmaceutical Sciences Andhra UniversityVisakhapatnamAndhra PradeshIndia-530003 Department of Botany College of Science and TechnologyAndhra University.VisakhapatnamAndhra PradeshIndia-530003

Objective:To evaluate bepato protective and antioxidant capacity of melochia corchorifolia （***）aerial part ***:Antioxidant activitywas evaluated by using three free radicals（Superoxide,Hydroxyl and DPPH） and hepatoprotective activity was assessed against CCl4 induced liver intoxication in ***:The extracts produced concentration dependent percentage protection in decrease of serum enzymes and percentage inhibition on free *** all extracts methanol extract showed better activity with percentage protection of SGOT（78.98%）,SGPT（79.65%）,ALP（82.48%） and total bilirubin（80.0%）levels against CCl4 liver intoxication and also methanolic extract showed better activity with IC50 values on superoxide. hydroxyl and DPPH radicals were 127μg.240μg and 179μ***:From the results obtained during the study it could be concluded that *** aerial part extracts have antioxidant and hepaloprotective *** study is necessary for isolation and characterization of bioactive molecules which are responsible for hepatoprotective and antioxidant activity.

关键词： melochia corchorifolia Aerial parts Free radicals Antioxidant Activity CCl_4 Hepatoprotective activity

Optimizing machining parameters of wire-EDm process to cut Al7075/SiCp composites using an integrated statistical approach

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Advances in manufacturing 2016年第3期4卷 202-216页

作者： Thella Babu rao Department of mechanical Engineering K L UniversityGreen Fields Vaddeswaram GunturAndhra Pradesh 522502 India

metal matrix composites （mmCs） as advanced materials, while producing the components with high dimensional accuracy and intricate shapes, are more complex and cost effective for machining than conventional alloys. It is due to the presence of discontinuously distributed hard ceramic with the mmCs and involvement of a large number of machining control variables. However, determination of optimal machining conditions helps the process engineer to make the process efficient and effec- tive. In the present investigation a novel hybrid multi-response optimization approach is proposed to derive the economic machining conditions for mmCs. This hybrid approach integrates the concepts of grey relational analysis （GRA）, principal component analysis （PCA） and Taguchi method （Tm） to derive the optimal machining conditions. The machining experiments are planned to machine A17075/SiCp mmCs using wire-electrical discharge machining （WEDm） process. SiC particulate size and its weight percentage are explicitly considered here as the process variables along with the WEDm input variables. The derived optimal process responses are confirmed by the experimental validation tests and the results show satisfactory. The practical possibility of the derived optimal machining conditions is also analyzed and presented using scanning electron microscope （SEm） examinations. According to the growing industrial need of making high performance, low cost components, this investigation provides a simple and sequential approach to enhance the WEDm performance while machining mmCs.

关键词： Al7075/SiCP metal matrix composites(mmCs) Wire-electrical discharge machining (WEDm)Principal component analysis (PCA) Grey relationalanalysis (GRA) Taguchi method (Tm)

Leveraging ROTI map derived from Indonesian GnSS receiver network for advancing study of Equatorial Plasma Bubble in Southeast/East Asia

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Earth and Planetary Physics 2025年第1期9卷 101-116页

作者： Prayitno Abadi Ihsan n.muafiry Teguh n.Pratama Angga Y.Putra Suraina Gatot H.Pramono Sidik T.Wibowo Febrylian F.Chabibi Umar A.Ahmad Wildan P.Tresna Asnawi Research Center for Climate and Atmosphere Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia School of Electrical Engineering Telkom UniversityBandungIndonesia Directorate of Laboratory management Facilities and Science and Technology Park Indonesian National Research and Innovation Agency(BRIN)PontianakIndonesia Geophysics Laboratory Master Program in PhysicsUniversitas Gadjah Mada(UGM)YogyakartaIndonesia Research Center for Space Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia Indonesian Geospatial Information Agency(BIG) JakartaIndonesia Research Center for Photonics Indonesian National Research and Innovation Agency(BRIN)Tangerang SelatanIndonesia Department of Earth and Planetary Sciences Hokkaido UniversitySapporoJapan

This paper highlights the crucial role of Indonesia’s GnSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GnSS signals and degrade positioning *** by the Indonesian Geospatial Information Agency(BIG),the Indonesia Continuously Operating Reference Station(Ina-CORS)network comprises over 300 GnSS receivers spanning equatorial to southern low-latitude ***-CORS is uniquely situated to monitor EPB generation,zonal drift,and dissipation across Southeast *** provide a practical tool for EPB research,by sharing two-dimensional rate of Total Electron Content(TEC)change index(ROTI)derived from this *** generate ROTI maps with a 10-minute resolution,and samples from may 2024 are publicly available for further scientific *** preliminary findings from the ROTI maps of Ina-CORS are ***,the Ina-CORS ROTI maps reveal that the irregularities within a broader EPB structure persist longer,increasing the potential for these irregularities to migrate farther ***,we demonstrate that combined ROTI maps from Ina-CORS and GnSS receivers in East Asia and Australia can be used to monitor the development of ionospheric irregularities in Southeast and East *** have demonstrated the combined ROTI maps to capture the development of ionospheric irregularities in the Southeast/East Asian sector during the G5 Geomagnetic Storm on may 11,*** observed simultaneous ionospheric irregularities in Japan and Australia,respectively propagating northwestward and southwestward,before midnight,whereas Southeast Asia’s equatorial and low-latitude regions exhibited irregularities *** sharing ROTI maps from Indonesia and integrating them with regional GnSS networks,researchers can conduct comprehensive EPB studies,enhancing the understanding of EPB behavior across Southeast and East Asia and contributing significantly to ionosphe

关键词： Equatorial Plasma Bubble(EPB) GnSS receivers’network Indonesia Continuously Operating Reference Station(Ina-CORS) ionospheric map Rate of TEC change index(ROTI)map