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Mn0.8Zn0.2Fe2O4 nanoparticulates spinel ferrites:An approach to enhance the antenna field strength for improved magnitude versus offset(MVO)

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Progress in natural Science:Materials International 2014年第4期24卷 364-372页

作者： Majid niaz Akhtar nadeem.nasir Muhammad Kashif noorhana Yahya Mukhtar Ahmad Ghulam Murtaza Muhammad Azhar Khan M.H.Asif A.Sattar R.Raza M.Saleem S.n.Khan Department of Physics COMSATS Institute of Information Technology Electrical and Electronic Engineering Department Universiti Teknologi PETRONAS Fundamental and Applied Sciences Department National Textile University Fundamental and Applied Sciences Department Universiti Teknologi PETRONAS Centre for Advanced Studies in Physics G.C.University Department of Physics The Islamia University of Bahawalpur

Electromagnetic signals in deep reservoir are very weak so that it is difficult to predict about the presence of hydrocarbon in seabed logging(SBL) *** the present work,Mn0.8Zn0.2Fe2O4 nanoferrites were prepared by a sol–gel technique at different sintering temperatures of450 °C,650 °C and 850 °C to increase the strength of electromagnetic(em) ***,FESem,Raman spectroscopy and HRTem were used to analyze the phase,surface morphology and size of the *** properties of the nanoferrites were also measured using an impedance network ***,nanoferrites sintered at 850 °C with initial permeability of 200 and Q factor of 50 were used as magnetic feeders with the em *** scale experiments were performed to investigate the effect of magnetic field strength in scale *** and MATLAB softwares were also used to confirm the oil presence in scale *** was observed that the magnitude of the em waves for the antenna was increased up to 233%.Finally,the correlation values also show 208% increase in the magnetic field strength with the presence of the ***,antenna with Mn0.8Zn0.2Fe2O4 nanoferrites based magnetic feeders can be used for deep water and deep target hydrocarbon exploration.

关键词： nanoferrites Transmission Electron Microscopy Initial permeability Q factor Antenna

中年美国印第安人身体镉负荷与血压升高的关系

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中华高血压杂志 2017年第2期25卷 103-103页

作者：刘莉叶鹏 Franceschini n Fry RC Balakrishnan P navas-Acien A Oliver-Williams C Howard AG Cole SA Haack K Lange em Howard BV Best LG Francesconi KA Goessler W Umans JG Tellez-Plaza M

镉（Cd）是一种环境污染物,已知其与人群心血管病相关,但是镉与高血压的关系研究结果不一致。研究人员对美国印第安人（身体镉负荷高于美国全国人口平均水平）尿镉浓度（总身体负荷测定指标）与血压的关系进行分析。使用电感耦合等离子... 详细信息

镉（Cd）是一种环境污染物,已知其与人群心血管病相关,但是镉与高血压的关系研究结果不一致。研究人员对美国印第安人（身体镉负荷高于美国全国人口平均水平）尿镉浓度（总身体负荷测定指标）与血压的关系进行分析。使用电感耦合等离子体质谱法测定尿镉浓度,并依照尿肌酐浓度进行调整。结果：

关键词：身体负荷血压升高印第安人镉负荷美国电感耦合等离子体质谱法中年环境污染物

Additions of landscape metrics improve predictions of occurrence of species distribution models

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Journal of Forestry Research 2017年第5期28卷 963-974页

作者： rica Hasui Vinícius X.Silva Rogrio G.T.Cunha Flavio n.Ramos Milton C.Ribeiro Mario Sacramento Marco T.P.Coelho Diego G.S.Pereira Bruno R.Ribeiro Laboratório de Ecologia de Fragmentos Florestais(ECOFRAG) Instituto de Ciência da NaturezaUniversidade Federal de Alfenas Laboratório de Ecologia Espacial e Conservao(LEEC) Departamento de EcologiaUNESP Estao de Hidrobiologia e Piscicultura de Furnas–EHPF Programa de Pós-Graduao em Ecologia e Evoluo da Universidade Federal de Goiás Universidade Federal de Goiás Departamento de Ciências Florestais Universidade Federal de LavrasCmpus Universitário

Species distribution models are used to aid our understanding of the processes driving the spatial patterns of species’ habitats. This approach has received criticism, however, largely because it neglects landscape metrics. We examined the relative impacts of landscape predictors on the accuracy of habitat models by constructing distribution models at regional scales incorporating environmental variables (climate, topography, vegetation, and soil types) and secondary species occurrence data, and using them to predict the occurrence of 36 species in 15 forest fragments where we conducted rapid surveys. We then selected six landscape predictors at the landscape scale and ran general linear models of species presence/absence with either a single scale predictor (the probabilities of occurrence of the distribution models or landscape variables) or multiple scale predictors (distribution models + one landscape variable). Our results indicated that distribution models alone had poor predictive abilities but were improved when landscape predictors were added; the species responses were not, however, similar to the multiple scale predictors. Our study thus highlights the importance of considering landscape metrics to generate more accurate habitat suitability models.

关键词： Ecological niche model Generalized linear models Habitat suitability Landscape structure Maxent

Experimentation on Tool Wear and Surface Roughness in AISI D2 Steel Turning with WC Insert

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Modern Mechanical Engineering 2018年第3期8卷 204-220页

作者： n. López-Luiz O. Jiménez Alem.n F. Alvarado Hernández M. Montoya Dávila V. H. Baltazar-Hernández Centro de Tecnología Avanzada CIATEQ Doctorado en Manufactura Avanzada Aguascalientes México Departamento de Ingeniería de Proyectos CUCEI Universidad de Guadalajara Zapopan Jal México Maestria en Ciencia e Ingeniería de los Materiales Universidad Autónoma de Zacatecas Zacatecas México

The Taguchi method, based on an orthogonal arrangem.nt (L9, 33), the vari-ance analysis, the signal-to-noise ratios and the response surface methodol-ogy have been used to optimize maximum flank wear (VBmax) and surface roughness (Ra) of the cutting tool when turning a hardened steel AISI D2 (65 HRC) with PVD—TiAln coated WC insert upon dry environment. By em-ploying regression models;cutting speed, cutting depth and feed rate, which optimize maximum flank wear and surface roughness were validated. Results of relation signal-to-noise ratios, showed that with cutting speed of 200 m/min, cutting depth of 0.2 mm and feed rate of 0.20 mm/rev, Ra is opti-mized. With cutting speed of 150 m/min, cutting depth of 0.4 mm and feed rate of 0.3 mm/rev, VBmax is optimized. Through the variance analysis it was concluded that the depth of cut was the main parameter that affected on the surface roughness;whereas, the feed rate was the most influential parameter on the flank wear. Confirmation test results showed that the Taguchi method was very successful in the optimization of machining parameters for mini-mum surface roughness and flank wear in the turning of the D2 steel.

关键词： Turning Taguchi Method Wear of Cutting Tool Surface Roughness AISI D2

Insecticidal Activity of Annonaceous Acetogenins and Their Derivatives on <em>Spodoptera frugiperda</em>Smith (Lepidoptera: noctuidae)

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Journal of Agricultural Chemistry and Environment 2018年第3期7卷 105-116页

作者： José Ruiz Hidalgo Eduardo A. Parellada Alicia Bardón nancy Vera Adriana neske Instituto de Química Orgánica Facultad de Bioquímica Química y Farmacia UNT Tucumán Argentina Inquinoa-Conicet Facultad de Bioquímica Química y Farmacia UNT Tucumán Argentina Instituto de Farmacia Facultad de Bioquímica Química y Farmacia UNT Tucumán Argentina

Background: Annonaceous acetogenins enclose a large number of biological activities, among which the insecticidal stands out. Methods: We report herein the biocide effects of natural acetogenins from Annona squamosa, A.?muricata and A. montana seeds: annonacin, cis-annonacin, cis-annonacin-10- one, asimicin, rolliniastatin-2, cherimolin-1, cherimolin-2, almuñequin, and two β-OH acetogenins: laherradurin and itrabin on Spodoptera frugiperda Smith (Lepidoptera: noctuidae). Also, some acetylated and methoxy methylated ACG derivatives were synthesized and evaluated: annonacin (3 OAc), annonacin (4 OAc), asimicin (3 OAc), rolliniastatin-2 (3 OAc), rolliniastatin-2 (MOM), laherradurin (3 OAc) and itrabin (3 OAc). Results: The natural acetogenin rolliniastatin-2 (100 μg·g-1 of diet) produced the most important toxic action causing 100% mortality of early instar larvae. Derivatization of ACG yielded compounds that produced nutritional alterations. The incorporation of rolliniastatin-2 (3 OAc) and rolliniastatin-2 (3 MOM) (100 μg·g-1) into the artificial diet of Spodoptera frugiperdadisplayed the strongest antifeedant effects causing marked decreasings in larval growth and adult lethal malformations. Conclusion: natural acetogenins are promising metabolites for insect control. Derivatization of these compounds reduces their toxicity to early instar larvae.

关键词： Annonaceous Acetogenins Biocides Spodoptera frugiperda

Hadronic spectra from deformed AdS backgrounds

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Chinese Physics C 2020年第6期44卷 109-122页

作者： Eduardo Folco Capossoli Miguel Angel Martín Contreras 李丹凝 Alfredo Vega Henrique Boschi-Filho Instituto de Física Universidade Federal do Rio de Janeiro21.941-972-Rio de Janeiro-RJ-Brazil Departamento de Física/Mestrado Profissional em Práticas da Educação Básica(MPPEB) Colégio Pedro II20.921-903-Rio de Janeiro-RJ-Brazil Instituto de Física y Astronomía Universidad de ValparaísoA.Gran Bretaña 1111ValparaísoChile Department of Physics and Siyuan Laboratory Jinan UniversityGuangzhou 510632China

Because of the presence of modified warp factors in metric tensors,we use deformed AdS5 spaces to apply the AdS/CFT correspondence to calculate the spectra for even and odd glueballs,scalar and vector mesons,and baryons with different *** the glueball cases,we derive their Regge trajectories and compare them with those related to the pomeron and the *** the scalar and vector mesons,as well as baryons,the determined masses are compatible with the *** particular,for these hadrons we found Regge trajectories compatible with another holographic approach as well as with the hadronic spectroscopy,which present an universal Regge slope of approximately 1.1 GeV^2.

关键词： hadronic spectra AdS/QCD model Regge trajectories

Age,geochemistry and tectonic setting of Buqingshan ophiolites,north Qinghai-Tibet Plateau,China

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Age,geochemistry and tectonic setting of Buqingshan ophiolit...

Development of a Fractional Loop Antenna for emC Measurem.nt

中国科学院地质与地球物理研究所2003学术年会

作者： I.Pospelov O.Astrakhantsev n.Chamov Geological Institute Russian Academy of SciencesMoscow 109017Russia

The Buqingshan ophiolite complex is a sector of the A’nyemaqen ophiolite belt in the East Kunlum southern marginal suture zone in the northern part of the Qinghai-Tibet *** WnW-trending ophiolite complex consists of pretaperidetic,diabase,pillow basalt, massive basalt and pelagic sedimentary rocks including radiolarian *** have deter(?) that Early Paleozoic and Early Carboniferous-Early Permian ophiolites are present in this ophiolite complex that were pre(?)us(?)y thought of Permian-Middle Triassic age. A zircon U-Pb age of 467.2±0.9 Ma for gabbro,and a Rb-Sr isochron age of 481±130Ma for diabase and gabbro have been obtained from the Early Paleozoic ophiolite slice,and Middle-Late Ordovician acritarchs have been found in the melange matrix that envelopes the *** interpret the first two ages to represent the formation age of the ophiolite.(?)ranodiofite- tonalite plutons with a zircon U-Pb age of 402±24 Ma intrude the *** Carboniferous-Early Permian radiolaria(?)s have been discovered in cherts and argillaceous cherts in the second ophiolite *** indicates that metaperidotites in th first slic(?) rensent a depleted ocean lithosphere *** mafic rocks in the Early Paleozoic ophiolite are of n-MORB type with sma(?) amount of T-MORB,and they resulted from the magma from the depleted oceanic lithosphere mantle with little crustal ***(?)asa(?)s in the Early Carboniferous-Early Permian ophiolite have similar characteristics to the mafic rocks and also show DUPAI an(?)maly and a mixed source of DMM and emⅡ.The original formation environments of the two-stage ophiolites are both mid-oc(?) *** lines of evidence suggest that a mature Early Paleozoic Kunlun-Qilian-Qinling ocean basin and a mature Paleote(?)hyan ocean basin once existed in the study area.

关键词： Ophiolite Tibetan plateau East Kunlun Shan

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Development of a Fractional Loop Antenna for EMC Measurement

Age,geochemistry and tectonic setting of Buqingshan ophiolites,north Qinghai-Tibet Plateau,China

1997 International Symposium on Electromagnetic Compatibility

作者： P.K.Saha n.M.Alam Chowdhury Dept.of Electrical & Electronic Engineering Bangladesh University of Engineering and Technology(BUET)Dhaka-1000 Bangladesh

＜正＞A newly developed emC（Electromagnetic Compatibility） antenna is proposed in this paper which can simulate highly directive standard em（Electromagnetic） waves. The proposed antenna can be made by placing a one-sixth of conducting loop-wire（H-Loop） in front of a 60 degree corner *** mathematical model of such a quasishield probe called H-loop is *** characteristics of this antenna have been compared with those of the existing quarter loop antenna and a complete loop *** input impedance of the developed antenna is computed from the network representation of the H-Loop antenna.

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Age,geochemistry and tectonic setting of Buqingshan ophiolit...