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Chinese science Bulletin 2010年第8期55卷 730-735页

作者： GUAN hongXiang FENG Dong WU NengYou ChEN DuoFu ROBERTs h h WU DaiDai CAs Key Laboratory of Marginal sea Geology State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China CAs Key Lab of Renewable Energy and Gas hydrate Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Guangzhou 510640 China Graduate University of Chinese Academy of sciences Beijing 100049 China Coastal studies Institute Louisiana State University Baton Rouge LA 70803 USA

here we reported the fatty-acids and their δ13 C values in seep carbonates collected from Green Canyon lease block 185 (GC 185;sample GC-F) at upper continental slope (water depth:～540 m),and Alaminos Canyon lease block 645 (GC 645;sample AC-E) at lower continental slope (water depth:～2200 m) of the Gulf of *** than thirty kinds of fatty acids were detected in both *** fatty acids are maximized at C *** is a clear even-over-odd carbon number predominance in carbon number *** fatty acids are mainly composed of n-fatty acids,iso-/anteiso-fatty acids and terminally branched odd-numbered fatty acids (iso/anteiso).The low δ13 C values (-39.99‰ to -32.36‰) of n-C 12:0,n-C 13:0,i-C 14:0 and n-C 14:0 suggest that they may relate to the chemosynthetic communities at seep *** unsaturated fatty acids n-C 18:2 and C 18:1 △9 have the same δ13 C values,they may originate from the Beggiatoa/*** other fatty acids,the terminally branched fatty acids (iso/anteiso) show lower δ13 C values (as low as -63.95‰) suggesting a possible relationship to sulfate reducing bacteria,which is common during anaerobic oxidation of methane at seep sites.

关键词：脂肪酸含量碳酸盐岩大陆坡氨基酸 C值墨西哥湾渗透国际标准化组织

Experimental study of channel delay impact on throughput performance of TCP and its extensions in space

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Journal of Zhejiang University-science A(Applied Physics & Engineering) 2005年第10期6卷 1015-1020页

作者： WANG Ru-fa WANG Ru h. school of Computer science Gansu Institute of Political Science and Law Lanzhou 730070 China Department of Electrical Engineering. Lamar University Beaumont TX 77710-1829 USA

substantially long round trip time (RTT) in space channel hurts TCP interactions between the sending and receiving ends, and limits the usefulness and effectiveness of TCP feedback. space Communication Protocol standards-Transport Protocol (sCPs-TP) is a Transmission Control Protocol (TCP) enhancement method aimed at improving its performance in space and interplanetary Internet and is expected to have capability of being feasible applied to experimental evaluation of the effectiveness of sCPs-TP in coping with long channel delay. This paper presents an experimental evaluation of channel delay impact on throughput performance of sCPs-TP over LEO/GEO-stationary space links using a test-bed, compared with the widely deployed TCP.

关键词： Intemet protocols satellite communication Channel delay TCP sCPs-TP

The Zariski Topology on the second spectrum of a Module

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Algebra Colloquium 2014年第4期21卷 671-688页

作者： h. Ansari-Toroghy F. Farshadifar Department of Pure Mathematics Faculty of Mathematical Sciences University of Guilan P.O. Box 41335-19141 Rasht Iran

Let R be a commutative ring and M be an R-module. The second spectrum spec^s（M） of M is the collection of all second submodules of M. We topologize spec^s（M） with Zariski topology, which is analogous to that for spec（R）, and investigate this topolog- ical space. For various types of modules M, we obtain conditions under which spec^s（M） is a spectral space. We also investigate specs （M） with quasi-Zariski topology.

关键词： second submodule second spectrum cotop module spectral space Zariskitopology

Ion-Acoustic shock Waves in Nonextensive Electron-Positron-Ion Plasma

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Chinese Physics Letters 2015年第1期32卷 95-99页

作者： M. Ferdousi s. Yasmin s. Ashraf A. A. Mamun Department of Physics dahangirnagar University Savar Dhaka-1342 Bangladesh Department of Physics International University of Business Agriculture and Technology Uttara Dhaka Bangladesh

A rigorous theoretical investigation is made of ion-acoustic shock structures in an unmagnetized three-component plasma whose constituents are nonextensive electrons, nonextensive positrons, and inertial ions. The Burgers equation is derived by employing the reductive perturbation method. The effects of electron and positron nonextensivity and ion kinematic viscosity on the properties of these ion-acoustic shock waves are briefly discussed. It is found that shock waves with positive and negative potentials are obtained to depend on the plasma parameters. The entailment of our results may be useful to understand some astrophysical and cosmological scenarios including stellar polytropes, hadronic matter and quark-gluon plasma, protoneutron stars, dark-matter halos, etc., where effects of nonextensivity can play significant roles.

关键词： Ion-Acoustic shock Waves in Nonextensive Electron-Positron-Ion Plasma

DEGREE 3 ALGEBRAIC MINIMAL sURFACEs IN ThE 3-sPhERE

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Acta Mathematica scientia 2012年第6期32卷 2065-2084页

作者： Joe s.Wang 4 Ricado Ln St.LauisM063124USA

We give a local analytic characterization that a minimal surface in the 3-sphere s3 C R4 defined by an irreducible cubic polynomial is one of the Lawson＇s minimal tori. This provides an alternative proof of the result by Perdomo （Characterization of order 3 algebraic immersed minimal surfaces of s3, Geom. Dedicata 129 （2007）, 23 34）.

关键词： algebraic minimal surface 3-sphere cubic polynomial

A POTENTIAL METhOD FOR DETERMINING ThE hAZ PROPERTIEs IN WELDs UsING TWO-MATERIAL IMPREssION CREEP TEsT

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Acta Metallurgica sinica(English Letters) 2004年第4期17卷 591-596页

作者： W.sun T.h.hyde school of Mechanical Materials and Manufacturing Engineering University of Nottingham Nottingham NG7 2RD UKSchool of Mechanical Materials and Manufacturing Engineering University of Nottingham Nottingham NG7 2RD UK

The results of a theoretical and finite element (FE) investigation of a two-material impression creep test method, using a rectangular indenter, are presented. The method uses a general formulation for steady-state creep deformation for multi-material components in conjunction with the results of FE analyses. The practical application of the proposed technique, in determining the secondary creep properties of heat-affected zone (hAZ) materials in welds, for which conventional creep testing methods cannot be used, is considered. A number of numerical examples are used to describe solution procedures and to verify the method.

关键词： two-material impression creep general formulation creep property welds hAZ

Effect of particle size distribution on magnetic behavior of nanoparticles with uniaxial anisotropy

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Chinese Physics B 2018年第9期27卷 572-576页

作者： s Rizwan Ali Farah Naz humaira Akber M Naeem s Imran Ali s Abdul Basit M sarim sadaf Qaseem Department of Physics Federal Urdu University of Arts Science and Technology Department of Applied Chemistry and Chemical Technology University of Karachi Department of Computer science Federal Urdu University of Arts Science and Technology

The effect of particle size distribution on the field and temperature dependence of the hysteresis loop features like coercivity（hC）, remanence（MR）, and blocking temperature（TB） is simulated for an ensemble of single domain ferromagnetic nanoparticles with uniaxial anisotropy. Our simulations are based on the two-state model for T 〈 TB and the metropolis Monte-Carlo method for T 〉 TB. It is found that the increase in the grain size significantly enhances hC and TB. The presence of interparticle exchange interaction in the system suppresses hC but causes MRto significantly *** results show that the parameters associated with the particle size distribution（D（d,δ）） such as the mean particle size d and standard-deviation δ play key roles in the magnetic behavior of the system.

关键词： magnetic nanoparticles Monte Carlo simulations size distribution interparticle interaction hysteresis

Position Dependent spontaneous Emission spectra of a Λ-Type Atomic system Embedded in a Defective Photonic Crystal

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Communications in Theoretical Physics 2012年第1期57卷 115-122页

作者： s.Roshan Entezar Faculty of Physics University of TabrizTabrizIran

We investigate the position dependent spontaneous emission spectra of a A-type three-level atom with one transition coupled to the free vacuum reservoir and the other one coupled to a double-band photonic band gap reservoir with a defect mode in the band gap. It is shown that, for the atom at the defect location, we have a two-peak spectrum with a wide dark line due to the strong coupling between the atom and the defect mode. While, when the atom is far from the defect location （or in the absence of the defect mode）, the spectrum has three peaks with two dark lines due to the coupling between the atom and the photonic band gap reservoir with the largest density of states near the band edges. On the other hand, we have a four-peak spectrum for the atom at the space in between. Moreover, the average spontaneous emission spectra of the atoms uniformly embedded in high dielectric or low dielectric regions are described. It is shown that the atoms embedded in high （low） dielectric regions far from the defect location, effectively couple to the modes of the lower （upper） photonic band. however, the atoms embedded in high dielectric or low dielectric regions at the defect location, are coupled mainly to the defect modes. While, the atoms uniformly embedded in high （low） dielectric regions with a normal distance from the defect location, are coupled to both of defect and lower （upper） photonic band modes.

关键词： spontaneous emission defective photonic crystal dark line three-level atom

FORGING AsIA′s GLOBAL TRANsPARK IN ThE PEARL RIVER DELTA AT ZhUhAI

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Chinese Geographical science 2003年第4期13卷 300-309页

作者： Victor F s sIT .

The main purpose of the paper is to introduce the concept of the Global TransPark (GTP). It is a critical time to develop air logistics infrastructure in the New Economy. The paper also presents a brief review of the air cargo industry in the Asian-Pacific region and China,in particular China’s development in the industry as its economy has grown rapidly and globalized in the past two decades. The paper argues that China needs to develop a GTP to support its future growth,and explains why the Pearl River Delta-hong Kong-Macao city-region or Extended Metropolitan Region (EMR) is the best location. Finally,it proposes that Zhuhai Airport,one of the five airports in the EMR,is the best site for the GTP. New policies from Chinese government as well as close cooperation between local governments of Guangdong and the two special Administrative Regions of hong Kong and Macao will be needed to make the establishment of the GTP possible.

关键词： Global TransPark airport air cargo transport hong Kong Extended Metropolitan Region the Pearl River Delta New Economy

Where to catch'em all?-a geographic analysis of Pokémon Go locations

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Geo-spatial Information science 2017年第3期20卷 241-251页

作者： Levente Juhász hartwig h.hochmair Geomatics Program University of FloridaFort LauderdaleFLUSA

In 2016,Niantic Labs released Pokémon Go,an augmented reality smartphone game that attracted millions of users *** game allows users to“catch”Pokémons through their mobile cameras in different geographic locations that often correspond to prominent *** paper analyzes the distribution of Pokéstops,Pokémon gyms,and spawnpoints in selected urban areas of south Florida and *** identifies which socioeconomic variables and landuse categories affect the density of Pokéstops,and how Pokéstops and gyms cluster relative to each *** nearest neighbor analysis,this paper assesses also how actual Pokéstop locations are reflected in Yelp’s“Pokéstop nearby”*** show that black and hispanic neighborhoods are disadvantaged when it comes to crowd-sourced data coverage,that Pokéstops occur more frequently in commercial,recreational and touristic sites and around universities,and that Pokéstops tend to cluster around *** latter suggests that these point sets were generated by a similar location selection *** mitigate geographically linked biases,future versions of augmented reality and geo-games should aim to make them equally accessible in all areas,for example by placing extra resources,such as points of interest,in neighborhoods that are currently underrepresented in data coverage.

关键词： Pokémon Go VGI(Volunteered Geographic Information) Yelp cluster south Florida Boston hCl(human-computer interaction)