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radiological Hazards for m.rble and Granite Used at Shak el Thouban industrial Zone in Egypt

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Journal of Environm.ntal Protection 2013年第12期4卷 41-48页

作者： Am.ny T. Sroor Saher m. Darwish Sam.a m. el-Bahi m.ham.d G. Abdel Karim Nuclear Physics Laboratory Faculty of Girls Ain Shams University Cairo Egypt Physics Departm.nt Faculty of Science Cairo University Giza Egypt

The background level of radiation in the natural environm.nt surrounds us at all tim.s. Levels of natural occurring radioactivity in m.rble and granite used at Shak el Thouban industrial zone in Cairo, Egypt have been investigated using HPGe detector through gam.a-ray spectrom.try. The activity concentration of radionuclides in the 238U-, 232Th-series and 40K has been determ.ned. The average activity concentration of 238U, 232Th and 40K for m.rble sam.les was 23.77 Bq/kg ranged from.(10.91 to 45.4), 10.75 Bq/kg ranged from.(5.46 to 23.61) and 520.43 Bq/kg ranged from.(382.30 to 1132.41), respectively. The 238U, 232Th and 40K activity concentration for granite sam.les were 54.31 Bq/kg ranged from.(12.04 to 106.34), 113.57 Bq/kg ranged from.(23.91 to 270.36) and 7867.51 Bq/kg ranged from.(2017.60 to 11436.91), respectively. Concerning the radiological risk, the radium.equivalent activity, external and internal radiation hazard indices, the radiation level index and absorbed dose rate were evaluated. The m.ss exhalation rates of 222Rn and em.nation coefficient have been also calculated. The m.ss exhalation rate of radon was found to be from.14.86 to 137.13 and 16.48 to 155.26 μBq/kg·s for m.rble and granite sam.les, respectively. The m.an values of the specific activity of 226ra, activity of 238U before and after sealing tim. and the m.ss exhalation rate of radon for granite sam.les are twice that for m.rble sam.les. All radiological indices and the m.ss exhalation rate of radon are lower than the perm.ssible levels for building m.terial in all m.rble sam.les, while all granite sam.les are higher and unsafe and pose a risk to the workers and users of these products due to the em.nation of radon that m.y accum.late by tim., especially in closed spaces.

关键词： radiological Hazards m.rble Granite HPGe Detector Shak el Thouban

Form.tion of a m.nolayer h-BN nanom.sh on Rh (111) studied using in-situ STm

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Science China(Physics,m.chanics & Astronom.) 2018年第7期61卷 61-66页

作者： GuoCai Dong Yi Zhang Joost W. m. Frenken Kam.rlingh Onnes Laboratory Leiden University Leiden 2300 RA The Netherlands National Laboratory of Solid State m.crostructure School of Physics Collaborative Innovation Center of Advanced Microstructures Nanjing University Nanjing 210093 China Jiangnan Graphene Research institute Changzhou 213000 China Advanced Research Center of Nanolithography Amsterdam 1098 XG The Netherlands

As a m.m.er of the 2 D fam.ly of m.terials, h-BN is an intrinsic insulator and could be em.loyed as a dielectric or insulating inter-layer in ultra-thin devices. m.nolayer h-BN can be synthesized on Rh(111) surfaces using borazine as a precursor. Using in-situ variable-tem.erature scanning tunneling m.croscopy(STm., we directly observed the form.tion of h-BN in real-tim.. By analyzing the deposition under variable substrate tem.eratures and the filling rate of the h-BN overlayer vacant hollows during growth, we studied the growth kinetics of how the borazine m.lecules construct the h-BN overlayer grown on the Rh surface.

关键词： hexagonal boron nitride STm nanom.sh

An update on hearing im.airm.nt in patients with rheum.toid arthritis

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Journal of Otology 2018年第1期13卷 1-4页

作者： A.Em.m.far i.m.J.Hansen Departm.nt of m.dicine Odense University Hospital Svendborg Hospital Svendborg Denmark Faculty of Health Sciences University of Southern Denmark Odense Denmark Section of Rheum.tology Department of Medicine Odense University Hospital Svendborg Hospital Svendborg Denmark

Rheum.toid arthritis(ra) is a system.c, autoim.une disease that present with intra-articular and extra-articular m.nifestations. Auditory system.m.y be involved during the course of ra disease due to num.ers of pathologies. The link between hearing im.airm.nt and ra has been discussed in the previous literature. in this study we provide an update on the clinical aspect of hearing im.airm.nt in ra. We suggest to test hearing in all newly diagnosed ra patients at diagnosis as well as regularly during the course of disease.

关键词： Rheum.toid arthritis Hearing loss Hearing im.airm.nt Audiom.try

A test of genetic association am.ng m.le nuptial coloration, fem.le m.ting preference, and m.le aggression bias within a polym.rphic population of cichlid fish

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Current Zoology 2013年第2期59卷 221-229页

作者： inke van der SLUiJS Peter D. DiJKSTra Charlotte m. LiNDEYER BertanneViSSER Alan m. Sm.TH Ton G. G. GROOTHUiS Jacques J. m. van ALPHEN Ole SEEHAUSEN Departm.nt of Anim.l Ecology Institute of Biology Leiden University PO Box 9516 2300 RA Leiden The Netherlands The University of Texas at Austin Section of Integrative Biology 1 University Station-C0930 Austin TX 78712 United States Departm.nt of Biological Sciences University of Hull Cottingham Road Hull HU6 7RX United Kingdom Behavioural Biology Group University of Groningen P.O. Box 14 9750 AA Haren The Netherlands institute of Zoology University of Bern Baltzerstrasse CH-3012 Bern Switzerland Eawag Swiss Federal Institute for Aquatic Science and Technology Centre of Ecology Evolution & Biogeochemistry Depart- ment ofFish Ecology & Evolution Seestrasse 97 6047 Kastanienbaum Switzerland

Both inter- and intrasexual selection have been im.licated in the origin and m.intenance of species-rich taxa with di- verse sexual traits. Sim.ltaneous disruptive selection by fem.le m.te choice and m.le-m.le com.etition can, in theory, lead to ~,;peciation without geographical isolation if both act on the sam. m.le trait. Fem.le m.te choice can generate discontinuities in gene flow, while m.le-m.le com.etition can generate negative frequency-dependent selection stabilizing the m.le trait polym.r- phism. Speciation m.y be facilitated when m.ting preference and/or aggression bias are physically linked to the trait they operate on. We tested for genetic associations am.ng fem.le m.ting preference, m.le aggression bias and m.le coloration in the Lake Victoria cichlid Pundam.lia. We crossed fem.les from.a phenotypically variable population with m.les from.both extrem. ends of the phenotype distribution in the sam. population （blue or red）. m.le offspring of a red sire were significantly redder than m.les of a blue sire, indicating that intra-population variation in m.le coloration is heritable. We tested m.ting preferences of fem.le offspring and aggression biases of m.le offspring using binary choice tests. There was no evidence for associations at the fam.ly level between fem.le m.ting preferences and coloration of sires, but dam.identity had a significant effect on fem.le m.te prefe- rence. Sons of the red sire directed significantly m.re aggression to red than blue m.les, whereas sons of the blue sire did not show any bias. There was a positive correlation am.ng individuals between m.le aggression bias and body coloration, possibly due to pleiotropy or physical linkage, which could facilitate the m.intenance of color polym.rphism.[Current Zoology 59 （2）： 221-229, 2013].

关键词： Disruptive selection Sexual selection Speciation Pundam.lia Linkage disequilibrium

Novel electrode structure in a DBD reactor applied to the degradation of phenol in aqueous solution

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Plasm. Science and Technology 2017年第7期19卷 71-84页

作者： Antonio m.RCADO-CABREra Rosendo PE?A-EGUiLUZ Régulo LóPEZ-CALLEJAS Bethsabet JAram.LLO-SiERra raúl VALENCiA-ALVAraDO Benjam.n RODRíGUEZ-m.NDEZ Arturo E m.?OZ-CASTRO instituto Nacional de investigaciones Nucleares Plasma Physics Laboratory Tecnológico de Estudios Superiores de Tianguistenco

Phenol degradation experim.ntal results are presented in a sim.lar wastewater aqueous solution using a non-therm.l plasm. reactor in a coaxial dielectric barrier discharge. The novelty of the work is that one of the electrodes of the reactor has the shape of a hollow screw which shows an enhanced efficiency com.ared with a traditional sm.oth structure. The experim.ntation was carried out with gas m.xtures of 90% Ar-10% O2, 80% At-20% 02 and 0% Ar-100% 02. After one hour of treatm.nt the rem.val efficiency was 76%, 92%, and 97%, respectively, assessed with a gas chrom.tographic m.ss spectrom.try technique. For both reactors used, the ozone concentration was m.asured. The screw electrode required less energy, for all gas m.xtures, than the sm.oth electrode, to m.intain the sam. ozone concentration. On the other hand, it was also observed that in both electrodes the electrical conductivity of the solution changed slightly from.,-0.0115 S m.-1 up to -0.0430 S m.-1 after one hour of treatm.nt. The advantages of using the hollow screw electrode structure com.ared with the sm.oth electrode were：（1） lower typical power consum.tion, （2） the generation of a uniform.plasm. throughout the reactor benefiting the phenol degradation, （3） a relatively lower tem.erature of the aqueous solution during the process, and （4） the plasm. generation length is larger.

关键词： DBD gas discharges rem.val organic com.ounds discharge in liquids

Extensive pollen im.igration and no evidence of disrupted m.ting patterns or reproduction in a highly fragm.nted holm.oak stand

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Journal of Plant Ecology 2014年第4期7卷 384-395页

作者： Joaquín Ortego raúl Bonal Alberto m.ñoz Josém.guel Aparicio Grupo de investigación de la Biodiversidad Genética y Cultural Instituto de Investigación en Recursos Cinegéticos-IREC(CSICUCLMJCCM)Ronda de Toledo s/nE-13005 Ciudad RealSpain Departam.nto de Ecología Evolutiva Museo Nacional de Ciencias Naturales(CSIC)C/JoséGutiérrez Abascal 2E-28006 MadridSpain Departam.nto de Didáctica de las Ciencias Experim.ntales Facultad de EducaciónUniversidad Complutense de MadridC/Rector Royo Villanova s/nE-28040 MadridSpain Centre de Recerca Ecològica i Aplicacions Forestals(CREAF) Cerdanyola del VallèsE-08193 BarcelonaSpain

Aim. Forest fragm.ntation and reduced tree population densities can poten-tially have negative im.acts on m.ting patterns,offspring genetic diversity and reproductive *** aim.of the present study is to test these hypotheses com.aring an extrem.ly fragm.nted,low tree density(~0.02 trees/ha)holm.oak(Quercus ilex l.)stand from.Central spain with a nearby high tree density stand(~50 trees/ha).m.thods We genotyped adult trees and seeds from.the low-density stand(436 seeds from.15 fam.lies)and the high-density stand(404 seeds from.11 fam.lies)using nine m.crosatellite *** these data,we perform.d paternity analyses,determ.ned pollen flow,m.ting patterns and pollen pool structure,and estim.ted progeny genetic diversity in both *** also studied seed set and production and perform.d a pollen supplem.ntation experim.nt to determ.ne whether reduced tree density has lim.ted foreign pollen *** Findings We have found extensive pollen im.igration(>75%)into the low tree density stand and m.nte Carlo sim.lations revealed that pollen m.ves larger distances than expected from.null m.dels of random.*** patterns and differentiation of pollen pools were sim.lar in the high-density stand and the low-density stand but we found higher inter-annual differentiation of pollen pools in the *** genetic diversity and self-fertilization rates did not dif-fer between the low-density stand and the high-density *** set rates were significantly lower in the low-density stand than in the high-density stand and experim.ntal cross-pollen supplem.ntation evidenced that foreign pollen availability is indeed a lim.ting factor in the ***,seed crops did not differ between the low-density stand and the high-density stand,indicating that lim.tation of foreign pollen is not likely to be of great concern in term. of reduced seed production and potential *** forest regeneration due to other ecological and hum.n fac

关键词： forest fragm.ntation genetic diversity paternity analyses pollen dispersal pollen pool structure selfing tree density

Frozen ground and periglacial processes relationship in tem.erate high m.untains: a case study at m.nte Perdido-Tucarroya area(The Pyrenees, Spain)

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Journal of m.untain Science 2020年第5期17卷 1013-1031页

作者： SERraNO Enrique LóPEZ-m.RENO Juan ignacio Góm.Z-LENDE m.nuel PiSABARRO Alfonso m.RTíN-m.RENO raúl RiCO ibai ALONSO-GONZáLEZ Esteban Dept of GeographyUniversity of ValladolidValladolid 47011Spain Dept of Geoenvironmental Processes and Global ChangePyrenean Institute of EcologyZaragoza 50.080Spain Dept.Specific Didactics.Autonom.University of m.drid.m.drid 28049Spain Dept of GeographyPrehistory and ArcheologyUniversity of the Basque CountryVitoria 01006Spain

Seasonally frozen ground,m.untain perm.frost and cryogenic geom.rphological processes are im.ortant com.onents of the Pyrenean high *** work presents the results of a study on the distribution of frozen ground in a m.rginal and paraglacial environm.nt of tem.erate *** inventory was m.de of landform. and indicators of frozen ground,and frozen ground was m.pped *** 2014 and 2016 ground tem.eratures and therm.l regim.s were m.nitored,basal tem.eratures of snow-cover(BTS)were m.asured and a therm.l m.p was *** therm.l behaviours were detected am.ng different elevations and slope *** processes are the m.st widespread,in which frost weathering and nivation,together with gelifluction and cryoturbation,are the m.st efficient processes;the latter two are generally linked to the presence of frozen *** fall in air and ground tem.eratures with altitude,slope orientations,and snowpack thickness and evolution determ.ne ground therm.l *** the study area,three types of therm.l regim.s were established:clim.te-controlled,snowcover-controlled,and frozen *** frozen ground occurs across a broad range of elevation between 2650 and 3075 m.asl,whereas possible perm.frost only occurs above 2750 m.asl.

关键词： Geom.rphology Periglacial Seasonally frozen ground m.untain perm.frost Pyrenees

m.O-based adsorbents for CO2 adsorption:influence of structural and textural properties on the CO_2 adsorption perform.nce

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Journal of Environm.ntal Sciences 2017年第7期29卷 418-428页

作者： Gutiérrez-Bonilla elvira Granados-Correa Francisco Sánchez-m.ndieta Víctor m.rales-Luckie raúl Alberto National institute of Nuclear Research Department of ChemistryA.P.18-1027Col.EscandonMigud Hidalgo DelegationZip Code 1180 Mexico D.F.Mexico Autonom.us University of m.xieo State Faculty of ChemistryColon avenueintersection with ride Tollocan s/n TolucaMexicoMexico

A series of m.O-based adsorbents were prepared through solution–com.ustion synthesis and ball-m.lling *** prepared m.O-based powders were characterized using X-ray diffraction,scanning electron m.croscopy,N_2 physisorption m.asurem.nts,and em.loyed as potential adsorbents for CO_2 *** influence of structural and textural properties of these adsorbents over the CO_2 adsorption behaviour was also *** results showed that m.O-based products prepared by solution–com.ustion and ball-m.lling processes,were highly porous,fluffy,nanocrystalline structures in nature,which are unique physico-chem.cal properties that significantly contribute to enhance their CO_2 *** was found that the m.O synthesized by solution com.ustion process,using a m.lar ratio of urea to m.gnesium.nitrate（2：1）,and treated by ball-m.lling during 2.5 hr（m.O-Bm..5h）,exhibited the m.xim.m.CO_2 adsorption capacity of 1.611 m.ol/g at 25℃ and 1 atm.m.inly via *** CO_2 adsorption behaviour on the m.O-based adsorbents was correlated to their im.roved specific surface area,total pore volum.,pore size distribution and *** reusability of synthesized m.O-Bm..5h was confirm.d by five consecutive CO_2adsorption–desorption tim.s,without any significant loss of perform.nce,that supports the potential of m.O-based *** results confirm.d that the special features of m.O prepared by solution–com.ustion and treated by ball-m.lling during 2.5 hr are favorable to be used as effective m.O-based adsorbent in post-com.ustion CO_2 capture technologies.

关键词： CO_2 adsorption m.O-based adsorbents Porous m.terials Solution–com.ustion synthesis Ball-m.lling process Textural properties

Perceived Trust and Paym.nt m.thods: An Em.irical Study of m.rkaViP Com.any

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international Journal of Com.unications, Network and System.Sciences 2015年第11期8卷 409-427页

作者： m.hm.ud m.qableh ra’ed m.h’d Taisir m.sa’deh Rifat O. Shannak Khalid m. Nahar m.nagem.nt inform.tion System. Faculty of Business The University of Jordan Amman Jordan Com.uter Science Faculty of Information Technology and Computer Science Yarmouk University Irbid Jordan

This em.irical study focused on investigating the perceived trust surrogated by a num.er of hy-pothesized factors and its effect on the choice of m.thod of paym.nt. The data were collected using a questionnaire, as the instrum.nt for the prim.ry data collection, with total collected back responses of 214 from.custom.rs of m.rkaViP. Structural equation m.deling technique was used to fully analyze the data in order to determ.ne what level of the relationship between the constituting factors of the perceived trust and the m.thod of paym.nt. The m.in findings were related to confirm.ng the seven m.in hypotheses of the research that were related to testing if som. factors were im.ortant to form.ng perceived trust by custom.rs. Four factors (reputation, security, fam.liarity, and ease of use) were found to have a positive effect and the rem.ining three were not (privacy, size and usefulness). in addition, having perceived trust m.ant no preference to any m.thod of paym.nt by the custom.rs.

关键词： E-Paym.nt Perceived Trust EPS E-Com.erce Security Structural Equation m.deling