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Multifractal modelling and spectrum analysis: Methods and applications to gamma ray spectrometer data from southwestern nova scotia, canada

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science China Earth sciences 2006年第3期49卷 283-294页

作者： CHEnG Qiuming1,2 1. state key lab of Geological Processes and Mineral Resources, China university of Geosciences, Wuhan 430074, China 2. department of Earth and space science and Engineering, department of Geography, York university, 4700 keele street, Toronto, ontario, M3J 1P3, canada 1. state key lab of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China 2. department of Earth and space science and Engineering Department of Geography York University 4700 Keele Street Toronto Ontario M3J 1P3 Canada

Multifractal spectrum, autocorrelation/semivariogram and power spectrum are three dif- ferent functions characterizing a field or measure from different aspects. These functions are interre- lated in such that the autocorrelation/semivariogram and power spectrum are related to the low order statistical moments (0 to 2 nd) which may determine the local multifractality (τ ″(1)) of a multifractal measure. A better understanding of the interrelationships among these three functions is important because, on one hand, the multifractal modelling characterizes a multifractal measure in a more de- tailed manner since it involves moments of all orders. On the other hand, the commonly used semivariogram and power spectrum functions can be used as alternatives to study the dominant mul- tifractal properties around the mean measure. Moreover, semivariogram and power-spectrum func- tions provide spatial and spectral information, which is highly valued in geological applications. A new fractal relation found between area and power-spectrum will be useful for investigation of new meth- ods of spatial-spectral analysis for pattern recognition, anomaly separation, classification, etc. These results have been demonstrated with the case study of modelling gamma ray spectrometer data from the mineral district, southwestern nova scotia, canada. The results have shown that the values of uranium (U), thorium (Th) and potassium (k) may possess monofractal properties whereas the ratios of these values show high multifractality. The values of the ratios U/k and U/Th show relatively large variances and may provide more information for distinguishing the distinct phases of the granites, country rocks as well as possible gold mineralization-associated regional hydrothermal alteration zones. In addition, the power spectra for U, Th, k, U/Th and U/k consistently show two distinct power-law relationships for two ranges of wave number 12≤ω ≤160 km and 0≤ω ≤12 km. These properties might provide usefu

关键词： gamma ray spectrometer data, gold mineralization, alteration zones, multifractal modelling, spectral analysis, GIs.

Correlations between recombination rate and intron distributions along chromosomes of ***

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Progress in natural science:Materials International 2009年第4期19卷 517-522页

作者： Hong li a,b, Guoqing liu a, Xuhua Xia b a school of Physical science and Technology, Inner Mongolia university, Hohhot 010021, China b department of Biology, university of Ottawa, Ottawa, Ont., canada k1n 6n5 [a]school of Physical science and Technology Inner Mongolia University Hohhot 010021 China [b]Department of Biology University of Ottawa Ottawa Ont. Canada K1N 6N5

Generally speaking, the intron size positively correlates with recombination rate in Caenorhabditis elegans genome. Here, we analyze the correlations between recombination rate and some measures of different intron lengths so as to know whether the recombination influences the introns of different lengths in the same way. Results show that the correlation between the recombination rate and the percentage of short introns (s negative, but the correlation between the recombination rate and the percentage of introns that are larger than 500 bp is positive. Average intron length correlates positively with the recombination rate for introns whose length is in the range of 100-1000 bp. We speculate that the recombination mainly exerts impact on introns whose length ranges from 100-1000 bp. We also show that the average intron number per gene correlates negatively with the recombination rate.

关键词： Recombination rate Percentage of introns Intron length Intron number per gene C. elegans

Generation of polarized electron beams through self-injection in the interaction of a laser with a pre-polarized plasma

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High Power laser science and Engineering 2024年第3期12卷 62-68页

作者： l.R.Yin X.F.li Y.J.Gu n.Cao Q.kong M.Büscher s.M.Weng M.Chen Z.M.sheng key laboratory of nuclear Physics and Ion-beam Application(MoE) Institute of Modern PhysicsDepartment of Nuclear Science and TechnologyFudan UniversityShanghaiChina state key laboratory of High Field laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaiChina sAnkEn(Institute of scientific and Industrial Research) Osaka UniversityOsakaJapan sichuan Research Institute Shanghai Jiao Tong UniversityChengduChina Peter Grünberg Institut(PGI-6) Forschungszentrum JülichJülichGermany Institut für laser-und Plasmaphysik Heinrich-Heine-Universität DüsseldorfDüsseldorfGermany key laboratory for laser Plasmas(MoE) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghaiChina Collaborative Innovation Center of IFsA Shanghai Jiao Tong UniversityShanghaiChina Tsung-Dao lee Institute Shanghai Jiao Tong UniversityShanghaiChina

Polarized electron beam production via laser wakefield acceleration in pre-polarized plasma is investigated by particlein-cell *** evolution of the electron beam polarization is studied based on the Thomas±Bargmann±Michel±Telegdi equation for the transverse and longitudinal self-injection,and the depolarization process is found to be influenced by the injection *** the case of transverse self-injection,as found typically in the bubble regime,the spin precession of the accelerated electrons is mainly influenced by the ***,in the case of longitudinal injection in the quasi-1D regime(for example,*** et al.,***.110,135002(2013)),the direction of electron spin oscillates in the laser *** the electrons move around the laser axis,the net influence of the laser field is nearly zero and the contribution of the wakefield can be ***,an ultra-short electron beam with polarization of 99%can be obtained using longitudinal self-injection.

关键词： laser wakefield acceleration longitudinal self-injection particle-in-cell simulation polarized electron beam

Adsorption of yttrium(Y^(3+)) and concentration of rare earth elements from phosphogypsum using chitin and chitin aerogel

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Journal of Rare Earths 2024年第4期42卷 775-782页

作者： Glaydson s.dos Reis Diana Pinto sabrina F.lütke Eder C.lima luis F.O.silva Irineu A.s.De Brum Guilherme l.Dotto department of Forest Biomaterials and Technology Biomass Technology Centre Swedish University of Agricultural SciencesUmeaE13Swedn Universidad De la Costa Calle 58#55-66080002BarranquillaAtlanticoColombia Research Group on Adsorptive and Catalytic Process Engineering(EnGEPAC) Federal University of Santa MariaAv.Roraima100079705900Santa MariaRSBrazil Institute of Chemistry Federal University of Rio Grande do Sul90040060Porto AlegreBrazil

Chitin powder and chitin-aerogel were prepared from shrimp wastes and used to uptake Y^(3+)from aqueous solutions and concentrate this rare earth element from phosphogypsum(PG).Chitin aerogel displays a specific surface area of 945 m^(2)/g,while chitin powder is 3.6 m^(2)/g,which largely influences its adsorption *** the adsorption in synthetic solutions,the effect of pH on Y^(3+)removal is strong for chitin powder *** contrast,no big pH influence was detected for chitin *** interactions and chelation can highlight the proposed mechanism of Y^(3+)on chitin adsorbents for the powder and ***,in addition to these interactions,pore filling/pore diffusion is the main mechanism of Y^(3+)removal in the chitin *** aerogel is efficient in concentrating 8 times the Y^(3+)from PG,a very complex *** complex chitin aerogel-Y^(3+)can be a secondary source of rare earth elements for other applications.

关键词： Rare earths sustainable material Chitin powder Chitin porous aerogel Yttrium adsorption and recovery

In vivo and in vitro study of resorbable magnesium wires for medical implants:Mg purity,surface quality,Zn alloying and polymer coating

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Journal of Magnesium and Alloys 2024年第6期12卷 2472-2488页

作者： k.Tesar J.luňácková M.Jex M.Žaloudková R.Vrbová M.Bartoš P.klein l.Vištejnová J.Dušková E.Filová Z.sucharda M.steinerová s.Habr k.Balík A.singh department of Materials Faculty of Nuclear Sciences and Physical EngineeringCzech Technical University in PragueTrojanova 13Prague 12000Czech Republic Institute of Physics Czech Academy of SciencesNa Slovance 2Prague 18221Czech Republic Institute of Dental Medicine First Faculty of MedicineCharles University and General University Hospital in PragueKaterinská32Prague 12801Czech Republic department of Physics Faculty of Nuclear Sciences and Physical EngineeringCzech Technical University in PragueBrehová7Prague 11519Czech Republic department of Composites and Carbon Materials Institute of Rock Structure and MechanicsCzech Academy of SciencesV Holešovickách 41Prague 18209Czech Republic Institute of Anatomy First Faculty of MedicineCharles UniversityU Nemocnice 3Prague 12800Czech Republic Biomedical Center Faculty of Medicine in PilsenCharles UniversityAlej Svobody 76Pilsen 32300Czech Republic department of Pathological Physiology Faculty of Medicine in PilsenCharles UniversityAlej Svobody 7632300 PilsenCzech Republic department of Histology and Embryology Faculty of Medicine in PilsenCharles UniversityAlej Svobody 7632300 PilsenCzech Republic Institute of Pathology First Faculty of MedicineCharles University and General University Hospital in PragueStudnickova 2Prague 12800Czech Republic department of Biomaterials and Tissue Engineering Institute of PhysiologyCzech Academy of SciencesVidenska 1083Prague 14200Czech Republic Research Center for structural Materials National Institute for Materials Science1-2-1 SengenTsukuba 305-0047Japan

Magnesium is an excellent material in terms of biocompatibility and its corrosion products can serve as an active source for new bone ***,localized corrosion and H_(2)generation limit the potential of Mg-based *** low-alloyed Mg-Zn wires can strongly reduce problems with large H_(2)bubbles and improve the mechanical properties considerably while maintaining excellent long-term *** pickling and a polymer coating can be effectively used to lower the rate of in vivo *** this work,microstructural,mechanical,and in vitro characterization of 250μm and 300μm extruded wires made from ultra-pure Mg,commercially pure Mg,Mg-0.15Zn,Mg-0.4Zn and Mg-1Zn was ***,Mg-0.4Zn wires together with a variant coated with a copolymer of l-lactide andε-caprolactone were tested in vivo on artificially damaged Wistar rat *** on the observed Mg-induced osteogenesis,polymer-coated Mg wires with a small addition of Zn are a perspective material for bone-support applications,such as cerclage and fixation wires.

关键词： Magnesium Resorbable Mg wire Mg-Zn implant degradation Biocompatibility study Zn grain boundary segregation

solid-state nMR of quadrupolar nuclei at ultrahigh-field:A sensitive probe for materials characterization

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Solid-state NMR of quadrupolar nuclei at ultrahigh-field:A s...

Mineralogical Zonation of Wall-Rock Alteration in Jiaodong Gold Province, north China

第十七届全国波谱学学术会议

作者： Yining Huang department of Chemistry,The university of Western ontario,london,ontario,canada,n6A 5B7

In the last several decades,solid-state nMR (ssnMR) spectroscopy has increasingly become an indispensable tool for materials characterization. In periodic table,more than 70% of the nMR active isotopes are quadrupolar...

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Journal of Earth science 1999年第1期18卷 20-24页

作者： Chen Guangyuan sun Daisheng shao Wei li shengrong Division of Genetic Mineralogy, China university of Geosciences, Beijing 100083 Fyfe s. William department of Earth sciences, university of Western ontario, london, ontario, canada, n6A 5B7 Chen

Mineralogical zonation of wall rock alterations in Mesozoic granitoids is summarized from 18 gold deposits in Jiaodong gold province on the Asian mobile continental margin of the west circum Pacific rim. This paper deals with wall rock alterations developed around gold mineralizations of the quartz vein type in granitoids and the wall rock alteration type in granitoid basement contacts along Mesozoic fault zones trending mostly nnE ssW and nE sW. Five alteration zones are distinguished from host rock to ore zone, namely the chloritization and sericitization zone, the hematitization rutilization and microclinization zone, the quartz sericitization zone, the pyrite quartz sericitization zone and the pyrite silicification zone. The former two are outer zones marked by incomplete alteration of first mafic and then felsic minerals of the granitoids, while the later three are inner zones marked by complete alteration of both mafic and felsic minerals of the granitoids leading to retrogressive sericitization and progressive silicification with participation of ore elements. The whole process proceeds under dynamometamorphism with high fugacity of volatiles. Wall rock alteration is the intermediate link between unaltered host rock and ore mineralization both in time and space. Development of the alteration zonation and its mineral composition controls genetic type of mineralization, size and grade of the deposit and location of the ore zones.

关键词： gold province wall rock alteration zonation mineralogy Jiaodong.

REsTUDY OF sHAnTUnGOsUCHUs BRACHYCEPHAlUs YOUnG, 1982

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古脊椎动物学报(中英文） 1996年第3期 194-201页

作者： lu Junchang Wu Xiaochun(Institute of Vertdrite Paleontology and Paleoanthropology, Chinese Acadmy of sciences Beijing 100044)(department of Vertebrate Palaeontology, Royal ontario Museum 100 queen's Park,Toronto, ontario M5s 2C6, canada)

Three species have been referred to shantungosuchus to date. The type species s. chuhsienensis (Young, 1961) is represented by an articulated skeleton preserved as an impression of its ventral surface.s. hangjinensis was recently described by Wu et al. (1994) on the basis of an incomplete skull (with the mandible) and the part of the postcranial skeleton. The third species is s. brachycephalus, which will be restudied in the present paper's brachycephalus was erected by Young for a specimen, consisting of partial skull and some postcranial elements (V4020). It was published in one of Young's posthumous papers in 1982. Because the specimen was not fully prepaired when it was studied, Young's original description is very simple and there ekist errors in his identification of bone structures. For example, the four associated cervical vertebrae were described as osteoderms; the teeth are point rather than blunt in tip; and the left ramus of the mandible was identified as the humerus. Further repairation of the specimen shows many unknown features, especially characters from the palate, mandible and vertebrae. Those are sighflcant in our understanding of the morphology of s. brachycephalus and also important in establishing interspecific relationships within the genus.

关键词： late Jurassic-Early Cretaceous Crocodyliformes Protosuchia

ABEl-POIssOn TYPE kERnEl AnD PRODUCT TYPE kERnEl On p-sERIEs GROUP

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Analysis in Theory and Applications 1998年第4期14卷 46-52页

作者： Guangcai Zhou, university of saskatchewan, canada department of Mathematics university of saskatchewan saskatoon, sk s7n 5E6 canada 1. department of Mathematics University of Saskatchewan S7N 5E6 Saskatoon SK Canada

let G be a p-series group and Ω be a compact subgroup of G. let λ(x,r) and λn (x,r) be Abelp-poisson type kernel and product type kernel on Ω respectively. In this paper we discuss the approximation properties of ... 详细信息

关键词： oscillatory integral operator multiplier singularity