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Mineralogy and geochemistry of Nb-,Ta-,Sn-,U-,Th-,and Zr-bearing granitic rocks from Abu rusheid shear zones,South Eastern desert,Egypt

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Chinese Journal Of Geochemistry 2011年第2期30卷 226-247页

作者： Ali M.A. Lentz d.r. Hall d.C. Nuclear Materials Authority P.O.530.El MaadiCairoEgypt department of Geology New Brunswick UniversityUNBCanada Microscopy and Microanalysis Facility New Brunswick UniversityUNBCanada

Granite-hosted,Nb-,Ta-,Sn-,U-,Th-,and Zr(Hf)-bearing mineralization from the Abu rusheid shear zones occurs about 97 km southwest of the town of Marsa Alam,South Eastern desert,*** SSE-trending brittle-ductile Abu rusheid shear zones crosscut the peralkalic granitic gneisses and cataclastic to mylonitic rocks(mylonite,protomlyonite,and ultramylonite).The northern shear zone varies in width from 1 to 3 m with a strike length of >500 m,and the southern shear zone is 0.5 to 8 m wide and >1 km *** shear zones locally host less altered lamprophyre and locally sheared granitic aplite-pegmatite *** rare-metal minerals,identified from the peralkalic granitic gneisses and cataclastic to mylonitic rocks are associated with muscovite,chlorite,quartz,fluorite,pyrite,magnetite,and rare biotite that are restricted to the Abu rusheid shear zones;these are columbite-tantalite and pyrochlore(***) in the northern shear zone and ferrocolumbite in the southern shear *** occurs as inclusions in the columbite-tantalite minerals.U-and Th-minerals(uraninite,thorite,uranothorite,ishikawaite,and cheralite) and Hf-rich zircon ***(?) zircon contains numerous inclusions of rutile,fluorite,U-Th and rEE minerals,such as uranothorite,cheralite,monazite,and *** variations in Ta/(Ta+Nb) and Mn/(Mn+Fe) in columbite range from 0.07-0.42 and 0.04-0.33,respectively,and Hf contents in zircon from 1.92-6.46 of the two mineralized shear zones reflect the extreme degree of magmatic *** samples of peralkalic granitic gneisses and cataclastic to mylonitic rocks from the southern shear zone have very low TiO2(0.02 wt%-0.04 wt%),Sr [(15-20)×10-6],and Ba [(47-78)×10-6],with high Fe2O3T(0.94 wt%-1.99 wt%),CaO(0.14 wt%-1.16 wt%),alkalis(9.2 wt%-10.1 wt%),rb [(369-805)×10-6],Zr [(1033-2261)×10-6],Nb [(371-913)×10-6],U [(51-108)×10-6],Th [(36-110)×10-6],Ta [(38-108)×10-6],Pb [(39-364)×10-6],Zn [(21-424)×10-6],Y [(8-304)×10-6],Hf

关键词： uranium thorium zircon columbite-tantalite fluorite monazite xenotime age dating granitic gneisses South Eastern desert Egypt

Tubeufiales,***.,integrating sexual and asexual generic names

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Fungal diversity 2014年第5期68卷 239-298页

作者： Saranyaphat Boonmee Amy Y.rossman Jian-Kui Liu Wen-Jing Li don-Qing dai Jayarama d.Bhat E.B.Gareth Jones Eric H.C.mckenzie Jian-Chu Xu Kevin d.Hyde Key Laboratory for Plant diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of ScienceKunming 650201YunnanChina World Agro forestry Centre East and Central Asia Office 132 Lanhei RoadKunming 650201China Institute of Excellence in Fungal research Mae Fah Luang UniversityMuangChiang Rai 57100Thailand School of Science Mae Fah Luang UniversityMuangChiang Rai 57100Thailand Systematic Mycology and Microbiology Laboratory USDA-ARSBeltsvilleMD 20705USA Formerly at department of Botany Goa UniversityGoa 403206India department of Botany and Microbiology King Saudi UniversityRiyadhSaudi Arabia Landcare research AucklandNew Zealand

Tubeufiaceae is based on the generic type Tubeufia,which is characterized by superficial,oval and bright ascomata,bitunicate asci,mostly long fusiform to filiform,transeptate ascospores and hyphomycetous asexual states with helicosporous *** species in this family are saprobic on terrestrial woody substrates and some are *** distinct morphology as well as combined LSU,SSU and TEF1 sequence analysis show that Tubeufiaceae should be accommodated in a new order Tubeufiales,which is introduced in this *** analyses of combined LSU and ITS sequences were used to resolve genera and species within the family *** this study,we examine and incorporate sexual and asexual states of genera in Tubeufiales to provide a modern treatment,based on single *** epitype for Tubeufia javanica,the type species of Tubeufia,is designated and represents Tubeufia sensu *** genera Acanthophiobolus,Acanthostigma,Boerlagiomyces,Chlamydotubeufia,Kamalomyces,Podonectria,Thaxteriella and Thaxteriellopsis are accepted,Acanthostigmina is reinstated,and the asexual genera Aquaphila,Helicoma,Helicomyces,Helicosporium and Tamhinispora are accepted in *** new genera Acanthohelicospora,Helicangiospora and Neoacanthostigma are *** genus Bifrontia is added to the family based on morphological *** incongruous morphological genera Acanthostigmella,Amphinectria,Chaetocrea,Chaetosphaerulina,Glaxoa,Malacaria,Melioliphila,Paranectriella,Puttemansia,rebentischia and Uredinophila are excluded from Tubeufiaceae despite having characteristic ascomata with setae and multiseptate long spores.A key to genera accepted in Tubeufiaceae is provided.

关键词： dothideomycetes Helicospores New genus Phylogeny Taxonomy Tubeufiaceae

Enhanced Trust Based Access Control for Multi-Cloud Environment

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Computers, Materials & Continua 2021年第12期69卷 3079-3093页

作者： N.r.rejin Paul d.Paul raj Technology PuduvoyalGummidipoondi601206India r M d Engineering College KavaraipettaiGummidipoondi601206India

Security is an essential part of the cloud *** ensuring the security of the data being communicated to and from the cloud server,a significant parameter called trust was ***-based security played a vital role in ensuring that the communication between cloud users and service providers remained unadulterated and *** most cloud-based data distribution environments,emphasis is placed on accepting trusted client users’requests,but the cloud servers’integrity is seldom *** paper designs a trust-based access control model based on user and server characteristics in a multi-cloud environment to address this *** proposed methodology consists of data encryption using Cyclic Shift Transposition Algorithm and trust-based access control *** this trust-based access control mechanism framework,trust values are assigned to cloud users using direct trust *** direct trust degree is estimated based on the following metrics:success and failure rate of interactions,service satisfaction index,and dishonesty *** addition to this,trust values are assigned to cloud servers based on the metrics:server load,service rejection rate,and service access *** role-Based Access control policy of each user is modified based on his trust *** the server fails to meet the minimum trust level,then another suitable server will be *** proposed system is found to outperform other existing systems in a multi-cloud environment.

关键词： Cloud computing trust access control cloud service provider cloud data user CSTA

Experimental study on correlation between turbulence and sound in a subsonic wind tunnel

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Acta Mechanica Sinica 2010年第4期26卷 531-539页

作者： M.d.Manshadi K.Ghorbanian M.r.Soltani department of Aerospace Engineering Sharif University of Technology

In this paper, the effects of turbulence on sound generation and velocity fluctuations due to pressure waves in a large subsonic wind tunnel are studied. A trip strip located at different positions in the contraction part or at one position in the diffuser of a large wind tunnel is used to investigate the aforementioned phenomenon, and the results indicate that the trip strip has significant effects on sound reduction. The lowest turbulence intensity and sound are obtained from a trip strip with a diameter of 0.91 mm located either at X/L = 0.79 or at X/L = 0.115 in the wide portion of the contraction. Furthermore, the effect of monopole, dipole and quadrupole sources of aerodynamic noise at different velocities is investigated, and it is demonstrated that the contribution of the monopole is dominant, while the shares due to the dipole and quadrupole remain less important. In addition, it is found that the sound waves have a modest impact on the measured longitudinal turbulence and are generated essentially by eddies.

关键词： Wind tunnel. Turbulence Sound Quadrupole term - Correlation

Effect of Post Heat Treatment on Corrosion resistance of Phytic Acid Conversion Coated Magnesium

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Journal of Materials Science & Technology 2013年第2期29卷 180-186页

作者： r.K. Gupta K. Mensah-darkwa d. Kumar Engineering research Center for revolutionizing Metallic Biomaterials (ErC-rMB) Department of Mechanical Engineering North Carolina A&T State University 1601 East Market Street Greensboro NC 27411 USA

An environment friendly chemical conversion coating for magnesium was obtained by using a phytic acid solution. The effect of post-coating 1heat treatment on the microstructures and corrosion properties of phytic acid conversion coated magnesium was investigated. It was observed that the microstructure and corrosion resistive properties were improved for the heat treated samples. The corrosion current density for bare magnesium, phytic acid conversion coated magnesium, and post-coating heat treated magnesium was calculated to be 2.48 ×10^-5, 1.18×10^-6, and 9.27 × 10^7 A/cm^2, respectively. The lowest corrosion current density for the heat treated sample indicated its highest corrosion resistive effect for the magnesium. The maximum corrosion protective nature of the heat treated sample was further confirmed by the largest value of impedance in electrochemical impedance spectroscopy studies.

关键词： Magnesium Phytic acid Corrosion Impedance spectroscopy Scanning electron microscopy

Microfungi on Tectona grandis(teak)in Northern Thailand

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Fungal diversity 2017年第1期82卷 107-182页

作者： Mingkwan doilom Asha J.dissanayake dhanushka N.Wanasinghe Saranyaphat Boonmee Jian-Kui Liu d.Jayarama Bhat Joanne E.Taylor Ali.H.Bahkali Eric H.C.mckenzie Kevin d.Hyde Key Laboratory for Plant diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of Sciences132 Lanhei RoadKunming 650201China Center of Excellence in Fungal research Mae Fah Luang UniversityChiang Rai 57100Thailand School of Science Mae Fah Luang UniversityChiang Rai 57100Thailand Institute of Plant and Environment Protection Beijing Academy of Agriculture and Forestry SciencesNo.9 of Shu Guang Hua Yuan Zhong LuHaidian DistrictBeijing 10097China Guizhou Key Laboratory of Agricultural Biotechnology Guizhou Academy of Agricultural SciencesGuiyang 550006GuizhouChina Formerly department of Botany Goa UniversityTaleigãoGoaIndia No.128/1-J Azad Housing SocietyCurcaGoa VelhaIndia royal Botanic Garden Edinburgh 20A Inverleith RowEdinburgh EH35LRUK department of Botany and Microbiology College of ScienceKing Saud UniversityP.O.Box 2455Riyadh 1145Saudi Arabia Manaaki Whenua Landcare research Private Bag 92170AucklandNew Zealand

To date there is virtually no information available concerning the fungi associated with Tectona grandis(teak)(Lamiaceae)in *** this study,samples of microfungi were collected from both asymptomatic stems and dead wood,and symptomatic branches,stem and leaves of *** 27 sites in six provinces(Chiang Mai,Chiang rai,Phayao,Phitsanulok,Phrae and Uttaradit Provinces).Morphology and combined multi-gene phylogeny(CAL,GAPdH,ITS,LSU,rPB2,SSU,TEF1 and TUB)were used to identify taxa.A total of 270 collections,representing 28 fungal species residing in 12 families,7 orders and 21 genera,with three species of uncertain taxonomic placement were *** these,one family,three genera and 14 species are new to *** new family,Pseudocoleodictyosporaceae is introduced based on its distinct lineage in the dothideomycetes and its unique morphology as compared to roussoellaceae and *** new genera are Neooccultibambusa,Pseudocoleodictyospora and *** newly described species are diaporthe neoraonikayaporum,***,***,***,Hermatomyces tectonae,***,Manoharachariella tectonae,Neooccultibambusa chiangraiensis,Pseudocoleodictyospora sukhothaiensis,***,***,rhytidhysteron tectonae,Subglobosporium tectonae and Tubeufia *** species are known published taxa including Alternaria tillandsiae,Berkleasmium talaumae,Boerlagiomyces macrospora,Ceratocladium purpureogriseum,Fusarium solani,Helicoma siamense,Lasiodiplodia theobromae,Macrovalsaria megalospora,Paradictyoarthrinium diffractum,Phaeoacremonium italicum,Sphaeropsis eucalypticola,Stachybotrys levispora,*** and Thaxteriellopsis *** or reference specimens are designated for Boerlagiomyces macrospora and Macrovalsaria *** megalospora is transferred from Botryosphaeriaceae to dothideomycetes genus,incertae sedis based on taxonomy and phylogenetic analysis,which indicate i

关键词： Ascomycota Basidiomycota dothideomycetes Sordariomycetes Taxonomy Multi-gene phylogenetics

Improved Pinning Center Morphology in HTS with Order-of-Magnitude Increase in J_c and B_pin Compared to Columnar Pinning

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Tsinghua Science and Technology 2003年第3期8卷 266-279页

作者： r.Weinstein A.Gandini r.Sawh d.Parks Beam Particle dynamics Laboratory Physics Departmentand Texas Center for Superconductivity and Advanced MaterialsUniversity of HoustonHoustonTexas 77204-5005USA

The motivation for continuous columnar pinning centers has been to provide maximum Upin. It has been assumed that this provides the best Jc and Bpin. Limitations on Jc and Spin observed for columnar pinning have been attributed to degradation of the order parameter and Tc. We examine columnar pinning by ionic damage and conclude instead that geometrical effects of columnar pinning on percolation path and on the number of pinning centers are the dominant limitations of columnar pinning, leading to a limit of Bpin- 4 T. Evidence suggests that multiple-in-line-defects (MILd) are far better suited to increase Jc and Bpin. The morphology of MILd pinning is reviewed. Ion energy loss per unit distance, Se, is found to be most promising in a regime almost diametrically opposite to that sought to maximize Upin. We expect Jc - 106 A/cm2 and Bpin > 40T from MILd pinning, despite sharply decreased Upin. Experimental confirmation is proposed.

关键词： improved pinning high critical current high field pinning ionic pinning centers columnar pinning limits

THErMOCHrOMIC POLYMEr MATErIALS

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Chinese Journal of Polymer Science 2007年第2期25卷 123-135页

作者： A.Seeboth A.Klukowska r.ruhmann d.L tzsch Fraunhofer Institute for Applied Polymer research Volmerstraβe 7B12489 BerlinGermany

Thermochromic polymers will play an extremely important role in the next future. The physical background of thermochromism and the state of development of thermochromic polymers based on light absorption effects are reported. In detail, the interactions between the polymer matrix and the thermochromic composite - composed of leuco or indicator dyes - are discussed on a molecular level. Thermochromic hydrogels with extremely high transparency, an outstanding switching behavior from colorless to colored or between different colors is presented. Preparation of thermosetting and thermoplastic polymers, including the resulting optical, and, for the first time, the mechanical properties are discussed in relation to matrix tuned high-resistant microcapsules.

关键词： Thermochromism Polymer matrix Microcapsule Organic dye Mechanical property.

Corrosion Protective Conversion Coatings on Magnesium disks Using a Hydrothermal Technique

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Journal of Materials Science & Technology 2014年第1期30卷 47-53页

作者： r.K.Gupta K.Mensah-darkwa d.Kumar department of Chemistry Pittsburg State University Engineering research Center for revolutionizing Metallic Biomaterials(ErC-rMB) Department of Mechanical EngineeringNorth Carolina A&T State University

A uniform, compact, and well adherent conversion coating of magnesium hydroxide has been formed on bioresorbable magnesium disks by means of a hydrothermal technique. Electrochemical results indicate that the coating brings about a significant reduction in magnesium corrosion in phosphate buffered saline （PBS） solution. It is also observed that corrosion resistance of the coating increases with an increase in treatment time, which in turn, increases the coating thickness. The protective behavior of magnesium hydroxide coating is attributed to its chemical inertness in PBS solution. The coatings are found to be free from pores that reduce the direct contact between corroding media and underlying magnesium.

关键词： Magnesium Polarization Electrochemical impedance spectroscopy (EIS) Scanning electron microscopy (SEM) Conversioncoating Corrosion