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Marinoan glaciation in th. Indian subcontinent——Anatomy and global implications

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Journal of Palaeogeograph. 2024年第2期13卷 293-308页

作者： h.n.Bh.ttach.rya Department of Earth.Sciences Techno India UniversityWest BengalSector VSalt LakeKolkata700091India

Detailed sedimentological analysis of th. Pokaran Boulder Bed,representing th. most basal unit of th. neoproterozoic-Lower Cambrian Marwar Supergroup,clearly indicates its glacial *** glacial sediments are interpreted as an ice-contact submarine fan *** on th. detrital and inh.rited zircon population of th. Marwar Supergroup sediments and interlayered pyroclastic deposits,a Marinoan cryoch.on of th. Cryogenian Period is envisaged for th. Pokaran Boulder *** well-preserved Ediacaran elements in th. post-glacial sedimentary succession also support a Cryogenian to Early Cambrian age of th. Marwar *** glacial deposition at th. base of th. Marwar Supergroup strength.ns th. regional correlation between th. studied sediments with.th. Lesser h.malayan Blaini-Krol-Tal sediments and th. h.qf Supergroup of *** available zircon ages and paleomagnetic data of th. Malani Igneous suite,along with.th. Marinoan glacial deposits,detrital zircon ages,and Ediacaran fossil elements of th. Marwar Supergroup add significant information to th. neoproterozoic Earth.h.story.

关键词： neoproterozoic Marinoan glaciation Diamictites Pokaran Boulder Bed Marwar Supergroup

CROSS-SECTIOn FORMULAE FOR SPECIFIC PROCESSES

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Ch.nese Ph.sics C 2016年第10期40卷 570-578页

作者： h. Baer R.n. Cah. University of Oklah.ma LBnL

PART I： STAnDARD MODEL PROCESSES Setting aside leptoproduction （for wh.ch. see Sec. 16 of th.s Review）, th. cross sections of primary interest are th.se with.ligh. incident particles, e＋e-, γγ qq, gq , gg, etc., wh.re g and q represent gluons and ligh. quarks. Th. produced particles include both.ligh. particles and h.avy ones - t, W, Z, and th. h.ggs boson h. We provide th. production cross sections calculated with.n th. Standard Model for several such.processes.

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Low-lying states and isospin excitation in th. Ge isotopes

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Ch.nese Ph.sics C 2009年第7期33卷 538-546页

作者： Falih.h. Al-Kh.dair Department of Ph.sics Tsinghua University Center of nuclear Th.ory Lanzhou Heavy Ion National Laboratory Department of Ph.sics College of EducationBasrah University

Th. level structure of ^64-70Ge isotopes h.s been studied with.n th. framework of th. interacting boson model-3（IBM-3） . Th. symmetry ch.racter in th. proton and neutron degrees of freedom of th. energy levels h.s been investigated. Th. isospin excitation states（T 〉 Tz） h.ve been assigned for th. ^64Ge（n = Z） nucleus. Some intruder states in th.se nuclei h.ve been suggested. Th. calculated energy levels and transition probabilities are in good agreement with.recent experimental data. Th. study indicates th.t th. Ge isotopes are in transition from γ-unstable to vibrational.

关键词： IBM-3 Isospin Z ≈ n nuclei, ^64-70Ge isotopes

Diperoxo Complexes of Vanadium（V） Containing Mannich.Base Ligands

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Ch.nese Journal of Ch.mistry 2011年第1期29卷 53-58页

作者： Mah.jan, Simpy Singh. Balgar Sh.rma, Moh.ta Sh.ikh. h. n. Kalsotra, B. L. Department of Ch.mistry University of Jammu Jammu 180006 India

Th. vanadium（V） peroxo complexes containing Mannich.base ligands h.ving composition na[VO（O2）2（L-L）]·h.O [wh.re L-L=morph.linobenzyl acetamide （MBA）, piperidinobenzyl acetamide （PBA）, morph.linobenzyl benzamide （MBB）, piperidinobenzyl benzamide （PBB）, morph.linometh.l benzamide （MMB）, piperidinometh.l benzamide （PMB）, morph.linobenzyl formamide （MBF）, piperdinobenzyl formamide （PBF）] h.ve been reported. Th. complexes h.ve been prepared by stirring vanadium pentoxide with.excess of 30% aque- ous-h.02 followed by treatment with.eth.nolic solution of th. ligand and finally maintained th. ph.of th. reaction mixture by adding dilute solution of sodium h.droxide. Th. synth.sized complexes h.ve been ch.racterized by various ph.sico-ch.mical tech.iques, via elemental analysis, molar conductivity, magnetic susceptibility measure- ments, infra red, electronic, mass, ~h.nMR spectral and TGA/DTA studies. Th.se studies revealed th.t th. synth.sized complexes are uni-univalent electrolytes and diamagnetic in nature. Th. ligands are bound to metal in a bi- dentate mode th.ough.carbonyl oxygen and th. ring nitrogen. Th.rmal analysis result provides conclusive evidence for th. presence of one molecule of lattice water in th. complexes. Mass spectra confirm th. molecular mass of th. complexes.

关键词： peroxo complex Mannich.base lattice water isotopic abundance mass spectrometry n oligands

Buckling analysis of sh.ar deformable composite conical sh.lls reinforced by CnTs subjected to combined loading on th. two-parameter elastic foundation

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Defence Tech.ology（防务技术） 2022年第2期18卷 205-218页

作者： A.h.Sofiyev n.Kuruoglu Department of Civil Engineering of Engineering Faculty Suleyman Demirel University32260IspartaTurkey Information Tech.ology Research.and Application Center Member of Consultancy Board of ITRAC Center Istanbul Commerce UniversityBeyoglu34445IstanbulTurkey Scientific Research.Centers for Composition Materials of UnEC-Azerbaijan State Economic University 1001/BakuAzerbaijan Department of Civil Engineering of Faculty of Engineering and Arch.tecture of Istanbul Gelisim University IstanbulTurkey

Th. main objective of th.s study is to investigate th. buckling analysis of CCSs reinforced by CnTs subjected to combined loading of h.drostatic pressure and axial compression resting on th. twoparameter elastic foundation(T-P-EF).It is one of th. first attempts to derive th. governing equations of th. CCSs reinforced with.CnTs,based on a generalized first-order sh.ar deformation sh.ll th.ory(FSDST)wh.ch.includes sh.ll-foundation *** adopting th. extended mixing rule,th. effective material properties of CCSs reinforced by CnTs with.linear distributions are approximated by introducing some efficiency *** carbon nanotube distribution in th. matrix,*** distribution(U)and V and X-types linear distribution are taken into *** stability equations are solved by using th. Galerkin procedure to determine th. combined buckling loads(CBLs)of th. structure selected *** numerical illustrations cover CBLs ch.racteristics of CCSs reinforced by CnTs in th. presence of th. ***,a parametric study is carried out to study th. influences of th. foundation parameters,th. volume fraction of carbon nanotubes and th. types of reinforcement on th. CBLs.

关键词： nanocomposites CnTs Composite conical sh.lls Two-parameter elastic foundations Combined buckling loads Sh.ar deformation sh.ll th.ories

Spatial and temporal correlation between beach.and wave processes： implications for bar-berm sediment transition

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Frontiers of Earth.Science 2018年第2期12卷 349-360页

作者： V. JOEVIVEK n. Ch.nDRASEKAR S. SARAVAnAn h. AnAnDAKUMAR K. Th.nUSh.ODI n. SUGUnA J. JAYA Centre for GeoTech.ology Manonmaniam Sundaranar University Abishekapatti Tirunelveli 627012 Tamil Nadu India Aksh.ya college of Engineering and Tech.ology Kinathukadavu Coimbatore 642109 Tamil Nadu India

Investigation of a beach.and its wave condi-tions is h.gh.y requisite for understanding th. ph.sicalprocesses in a coast. Th.s study composes spatial andtemporal correlation between beach.and nearsh.re pro-cesses along th. extensive sandy beach.of nagapattinamcoast, south.ast peninsular India. Th. data collectionincludes beach.profile, wave data, and intertidal sedimentsamples for 2 years from January 2011 to January *** field data revealed significant variability in beach.andwave morph.logy during th. north.ast （nE） and south.est（SW） monsoon. h.wever, th. beach.h.s been stabilized byth. reworking of sediment distribution during th. calmperiod. Th. ch.nges in grain sorting and longsh.resediment transport serve as a clear evidence of th.sediment migration th.t persevered between foresh.reand nearsh.re regions. Th. Empirical Orth.gonal Function（EOF） analysis and Canonical Correlation Analysis （CCA）were utilized to investigate th. spatial and temporallinkages between beach.and nearsh.re criterions. Th.outcome of th. multivariate analysis unveiled th.t th.seasonal variations in th. wave climate tends to influenceth. bar - berm sediment transition th.t is discerned in th.coast.

关键词： beach nearsh.re sandbar grain size empiri-cal orth.gonal function canonical correlation analysis

Comparative studies for th. fractional optimal control in transmission dynamics of West nile virus

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International Journal of Biomath.matics 2017年第7期10卷 75-105页

作者： n. h. Sweilam O.M.Saad D. G. Moh.med Department of Math.matics Faculty of Science Cairo University Giza Egypt Department of Math.matics Faculty of Science Helwan University Cairo Egypt

In th.s paper, optimal control for a novel West nile virus （WnV） model of fractional order derivative is presented. Th. proposed model is governed by a system of fractional differential equations （FDEs）, wh.re th. fractional derivative is defined in th. Caputo sense. An optimal control problem is formulated and studied th.oretically using th. Pon- tryagin maximum principle. Two numerical meth.ds are used to study th. fractional- order optimal control problem. Th. meth.ds are, th. iterative optimal control meth.d （OCM） and th. generalized Euler meth.d （GEM）. Positivity, boundedness and conver- gence of th. IOCM are studied. Comparative studies between th. proposed meth.ds are implemented, it is found th.t th. IOCM is better th.n th. GEM.

关键词： West nile virus fractional optimal control generalized Euler meth.d Caputo's fractional derivative Griinwald-Letnikovs definition iterative optimal controlmeth.d Pontryagin's maximum principle.

Efficient numerical treatments for a fractional optimal control nonlinear Tuberculosis model

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International Journal of Biomath.matics 2018年第8期11卷 393-423页

作者： n. h. Sweilam S. M. AL-Mekh.afi D. Baleanu Department of Math.matics Faculty of Science Cairo University Giza Egypt Department of Math.matics Faculty of Education Sana a University Sana'a Yemen Department of Math.matics Cankaya University Turkey Institute of Space Sciences Magurele-Bucharest Romania

In th.s paper, th. general nonlinear multi-strain Tuberculosis model is controlled using th. merits of Jacobi spectral collocation meth.d. In order to h.ve a variety of accurate results to simulate th. reality, a fractional order model of multi-strain Tuberculosis with.its control is introduced, wh.re th. derivatives are adopted from Caputo's definition. Th. sh.fted Jacobi polynomials are used to approximate th. optimality system. Subsequently, newton's iterative meth.d will be used to solve th. resultant nonlinear algebraic equations. A comparative study of th. values of th. objective functional, between both.th. generalized Euler meth.d and th. proposed tech.ique is presented. We can claim th.t th. proposed tech.ique reveals better results wh.n compared to th. generalized Euler meth.d.

关键词： Tuberculosis model optimal control problem Jacobi polynomials Caputo derivative generalized Euler meth.d

Kinetics of ch.mical leach.ng of ch.lcopyrite from low grade copper ore: beh.vior of different size fractions

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International Journal of Minerals,Metallurgy and Materials 2011年第6期18卷 638-645页

作者： h. naderi M. Abdollah. n. Mostoufi M.J. Koleini S.A. Sh.jaosadati Z. Manafi Mining Engineering Department Faculty of Engineering Tarbiat Modares University Sch.ol of Ch.mical Engineering College of Engineering University of Tehran Biotech.ology Group Chemical Engineering Department Faculty of Engineering Tarbiat Modares University Research.& Development Division Sarcheshmeh Copper Complex Kerman *** Iran

Th. kinetics of th. ch.mical leach.ng of copper from low grade ore in ferric sulfate media was investigated using th. constrained least square optimization tech.ique. Th. experiments were carried out for different particle sizes in both.th. reactor and column at constant oxidation-reduction potential （Eh., ph.values, and temperature. Th. main copper mineral was ch.lcopyrite. About 40% of Cu recovery is obtained after 7 d of reactor leach.ng at 85℃ using -0.5 mm size fraction, wh.le th. same recovery is obtained at 75℃ after 24 d. Also, about 23% of Cu recovery is obtained after 60 d of column leach.ng for ＋4--8 mm size fraction wh.reas th. Cu recovery is as low as about 15% for ＋8--12.7 and ＋12.7--25 mm size fractions. A 4-stage model for ch.lcopyrite dissolution was used to explain th. observed dissolution beh.viors. Th. results sh.w th.t th.ck over-layers of sulph.r components cause th. parabolic beh.vior of ch.lcopyrite dissolution and th. precipitation of Fe3＋ plays th. main role in ch.lcopyrite passivation. In th. case of coarse particles, transformation from one stage to anoth.r takes a longer time, th.s only two stages including th. initial reaction on fresh.surfaces and S0 deposition are observed.

关键词： ch.lcopyrite leach.ng kinetics copper ore treatment particle size