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Soil Pore Characterization Using f.ee Sof.ware and a Portab.e Optical Microscope

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作者： Chase Richard b.

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Pedosphere 2013年第4期23卷 503-510页

作者： L. f. PIRES f. S. b.RGES S. PASSONI A. b. PEREIRA Department of.Physics State University of Ponta Grossa (UEPG) Department of.Soil Science State University of Ponta Grossa (UEPG)

Total porosity （TP）, determined b. image analysis, pore type and pore size distrib.tion were evaluated on impregnated soil b.ocks f.om an undisturb.d b.azilian sandy loam soil using a digital portab.e optical microscope. The f.ee sof.ware Image J （version 1.40g） was used f.r image analysis. Procedures f.r soil image collection and analysis were presented. The image analysis allowed the evaluation of.pore sizes with diameters ranging f.om 20 to 〉 1 000 μm. The f.llowing types of.pores were also ob.ained： rounded, elongated and intermediate. The results M[owed the characterization of.the soil as moderately porous （TP = 21.6%）. Rounded, intermediate and elongated pores were responsib.e f.r 11.6%, 31.7% and 56.7% of.TP. In relation to pore size 51.1% of.TP was in the 100-500μm size class and a third of.TP came f.om the pores larger than 500μm.

关键词： image analysis soil porosity soil structure pore size distrib.tion

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Genetic outcomes f.om the translocations of.the critically endangered woylie

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Current Zoology 2013年第3期59卷 294-310页

作者： Carlo PACIONI Adrian f. WAYNE Peter b. S. SPENCER School of.Veterinary and Lif. Sciences Murdoch University Murdoch 6150 Western Australia Department of.Environment and Conservation Science Division Manjimup 6258 Western Australia

Translocations are an important conservation strategy f.r many species. However simply ob.erving demographic growth of.a translocated population is not suf.icient to inf.r species recovery. Adequate genetic representation of.the source population（s） and their long-term viab.lity should also b. considered. The woylie b.ttongia penicillata ogilb.i has b.en sub.ect to more f.rmal translocations f.r conservation than any other marsupial that, up until recently, has resulted in one of.the most suc- cessf.l species recoveries in Australia. We used mitochondrial and nuclear DNA markers to assess the genetic outcomes of.trans- located woylie populations. These populations have lost genetic variab.lity, dif.erentiated f.om their source population and the supplementation program on two island populations appears to have f.iled. We discuss the conservation implications that our re- suits have f.r managing threatened species, outline some general recommendations f.r the management of.present and f.ture translocations and discuss the appropriate sampling design f.r the estab.ishment of.new populations or captive b.eeding programs that may mitigate the genetic ＇erosion＇ seen in our study species. This research provides some practical outcomes and a pragmatic understanding of.translocation b.ology. The f.ndings are directly applicab.e to other translocation programs .

关键词： b.ttongia penicillata Macropod translocation Supplementation Microsatellites mtDNA

Transverse approach b.tween real world concentrations of.SO_2, NO_2, b.EX, aldehyde emissions and corrosion in the Grand Mare tunnel

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Journal of.Environmental Sciences 2012年第7期24卷 1240-1250页

作者： I. Ameur-b.uddab.ous J. Kasperek A. b.rb.er f. Harel b. Hannoyer GPM-UMR 6634 CNRS. Uf. Science and Technology University of Rouen BP 12 76801 Saint Etienne du Rouvray Cedex France LCAE Chemistry Department Science Faculty of Tunis Campus Universitaire 2092 El Manar Tunis Tunisie DIRNO Rue de Verdun 76160 Darnetal France

With regard to automotive traf.ic, a tunnel-type semi enclosed atmosphere is characterized b. a higher concentration of.gaseous pollutants than on urb.n traf.ic roads and highlights the gaseous ef.luent species having an impact on material degradation. Theref.re, a transverse approach b.tween air quality and its consequences upon the longevity of.materials is necessary, implying b.tter knowledge of.tunnel atmosphere and a b.tter understanding of.material degradation inside a tunnel f.r operating administration. Gaseous pollutant measurements carried out in a road tunnel in Rouen （Normandy） give the real world traf.ic concentrations of.experimental exposure conditions. The sampling campaigns, achieved in summer and winter include SO2, NO2, b.EX and aldehyde analyses. Ef.luent prof.les in the upward and downward tub.s have b.en estab.ished. The current work shows that SO2, NO〉 f.rmaldehyde, acetaldehyde, propanal and b.tanal must b. considered in the degradation process of.materials in a stuf.y environment. As regards NO,, its concentration depends on the modif.cation of.the automotive f.eet. The total aldehyde concentrations indicate no particular trend b.tween the two b.res. f.rmaldehyde, acetaldehyde, propanal, b.tanal and acrolein species are the most ab.ndant species emitted b. vehicles and represent 90% to 95% of.the total aldehyde emissions.

关键词： SO2 tunnel study aldehydes NO2 b.EX atmospheric corrosion

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Evaluation of.stress intensity f.ctors f.r b.-material interf.ce cracks using displacement jump methods

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Acta Mechanica Sinica 2017年第6期33卷 1051-1064页

作者： K. C. Nehar b. E. Hachi f. Cazes M. Hab.ussi Lab.ratoire de développement en mécanique et matériaux (LDMM) Université de Djelfa PB 3117 Djelfa Algeria Lab.ratoire des Sciences des Procédés et des Matériaux (LSPM) UPR 3407 CNRS Université Paris 13 Paris France

The aim of.the present work is to investigate the numerical modeling of.interf.cial cracks that may appear at the interf.ce b.tween two isotropic elastic materials. The extended f.nite element method is employed to analyze b.ittle and b.-material interf.cial f.tigue crack growth b. computing the mixed mode stress intensity f.ctors(SIf.. Three dif.erent approaches are introduced to compute the SIf.. In the f.rst one, mixed mode SIf.is deduced f.om the computation of.the contour integral as per the classical J-integral method,whereas a displacement method is used to evaluate the SIf.b. using either one or two displacement jumps located along the crack path in the second and third approaches. The displacement jump method is rather classical f.r mono-materials,b.t has to our knowledge not b.en used up to now f.r a b.material. Hence, use of.displacement jump f.r characterizing b.-material cracks constitutes the main contrib.tion of.the present study. Several b.nchmark tests including parametric studies are perf.rmed to show the ef.ectiveness of.these computational methodologies f.r SIf.considering static and f.tigue prob.ems of.b.-material structures. It is f.und that results b.sed on the displacement jump methods are in a very good agreement with those of.exact solutions, such as f.r the J-integral method, b.t with a larger domain of.applicab.lity and a b.tter numerical ef.iciency(less time consuming and less spurious b.undary ef.ect).

关键词： b.-material interf.ce crack Mixed mode stress intensity f.ctor Displacement jump X-f.M f.tigue crack growth

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Can Quick Release Experiments Reveal the Muscle Structure？ A b.onic Approach

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Journal of.b.onic Engineering 2012年第2期9卷 211-223页

作者： D. f. b. Haeuf.e M. Gunther R. b.ickhan S. Schmitt Institute of.Sports and Exercise-Science University of Stuttgart Allmandring 28 D-70569 Stuttgart Germany Stuttgart Research Centre f.r Simulation Technology （SRC SimTech） University of Stuttgart Pfaffenwaldring 7a D-70569 Stuttgart Germany Institute of.Motion Science Friedrich-Schiller-University Seidelstraβe 20 D-07749 Jena Germany

The goal of.this study was to understand the macroscopic mechanical structure and f.nction of.b.ological muscle with respect to its dynamic role in the contraction. A recently pub.ished muscle model, deriving the hyperb.lic f.rce-velocity relation f.om f.rst-order mechanical principles, predicts dif.erent f.rce-velocity operating points f.r dif.erent load situations. With a new approach, this model could b. simplif.ed and thus, transf.rred into a numerical simulation and a hardware experiment. Two types of.quick release experiments were perf.rmed in simulation and with the hardware setup, which represent two extreme cases of.the contraction dynamics： against a constant f.rce （isotonic） and against an inertial mass. b.th experiments revealed hyperb.lic or hyperb.lic-like f.rce-velocity relations. Interestingly, the analytical model not only predicts these extreme cases, b.t also additionally all contraction states in b.tween. It was possib.e to validate these predictions with the numerical model and the hardware experiment. These results prove that the origin of.the hyperb.lic f.rce-velocity relation can b. mechanically explained on a macroscopic level b. the dynamical interaction of.three mechanical elements. The implications f.r the interpretation of.b.ological muscle experiments and the realization of.muscle-like b.onic actuators are discussed.

关键词： f.rce-velocity relation isotonic quick release proof.of.concept artif.cial muscle

Comb.ned Ef.ect of.Dissipation and Thermal Mixed State on Entanglement in the Dispersive Limit

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Chinese Physics Letters 2008年第3期25卷 949-952页

作者： Ob.DA A. -S. f. HESSIAN H. A. MOHAMED A. -b. A. f.culty of.Science Al-Azhar University Nasr City Cairo Egypt f.culty of.Science Assiut University Assiut Egypt

We investigate the entanglement in the interacting system of.a single mode thermal f.eld and a single qub.t with dissipation in the dispersive limit. The inf.uence of.initial temperature of.thermal f.eld and atoms on ... 详细信息

关键词： JAYNES-CUMMINGS MODEL QUANTUM-MECHANICS CURRENT SITUATION 2-LEVEL ATOM DECOHERENCE f.ELD GENERATION DYNAMICS ENTROPY APPROXIMATION

Causes and Prognoses of.Acute f.ver in Children Aged 0 - 15 Who Are Hospitalized in the Department of.Pediatrics at the University Hospital (UH) Gab.iel Touré, b.mako-Mali

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Open Journal of.Pediatrics 2025年第1期15卷 10-20页

作者： f.toumata Léonie f. Diakité Mariam Kané Guediouma Demb.lé Leyla b. Maiga Niomo Kountao Nouhoum L. Traoré f.tou Magané Lala N. Sidib. Traoré Hawa Mady Niakaté Tiaria Sanogo Marianne Djouell Hawa G. Diall Djénèb. Konaté b.lco Maiga Karamoko Sacko Ab.oul K. Doumb.a Souleymane Sagara Ab.oul Aziz Diakité f.toumata Dicko Perinatal Clinic Mohammed VI Bamako Mali Central Directorate of.the Army Health Service Kati Mali Ref.rence Health Center of.the District IV Bamako Mali Department of.Pediatrics of.the University Hospital Center Gab.iel Tour Bamako Mali

f.ver is the primary reason f.r consultation and admission to pediatric emergency departments. The aim of.this study was to describ. the clinical, etiological and prognostic aspects of.acute f.ver in children aged 0 - 15 years. Patients and Methods: This was a prospective cross-sectional study f.om April 1, 2021 to March 31, 2022 and af.ected all children aged 0 to 15 years old with a temperature of.39˚C or higher (≥), having less than f.ve days and hospitalized in the pediatric department of.the Gab.iel Touré University Hospital. Results: During the study period, 150 children were included, the sex-ratio was 0.85. Children aged 0 - 5 years represented 71.4% of.the sample. Ref.rences represented more than half.of.the sample, or 58% of.cases. b.dy temperature was ab.ve 40˚C in 18.7% of.cases. f.nctional signs were dominated b. respiratory signs in 28% and digestive signs in 18%. Clinical pallor was f.und in 55.3% of.children associated with signs of.respiratory struggle in 70% of.cases and tachycardia in 40% of.patients. Anemia was present in 65.3% of.patients. Hyperleucocytosis and leukopenia were f.und in 45.3% and 43.3% of.patients respectively. The C-reactive protein was positive in 44.7% of.patients and Cytob.cteriological Examination and Chemistry of.Cereb.ospinal f.uid was positive in 8.7% of.cases. The thick drop was positive in 44.7% of.patients and b.ood cultures grew in 6 patients. Etiology was dominated b. severe malaria 54 cases (36%), pneumonia (19.3%), meningitis (12.6%), and in those under one month it was b.cterial neonatal inf.ction (8.6%). In our study, slightly more than one patient out of.three died during hospitalization, 36% (54 cases/150) and among these 70% (38 cases/54) were under 5 years old. The most lethal pathologies were severe malaria (36%), b.cterial pneumonia (19.3%), meningitis (12.6%), b.cterial neonatal inf.ctions (8.6%) and measles complicated b. pneumonia (5.3%). Mortality during hospitalization was 36% of.deaths (54 out of.150

关键词： Acute f.ver Aspects Clinical Etiological and Prognostic Children Mali

Kinetics of.the reaction of.OH radical with ethylf.uoroacetate,ethyl 4,4,4-trif.uorob.tyrate,and b.tylf.uoroacetate

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Journal of.Environmental Sciences 2025年第5期151卷 273-283页

作者： Pedro L.Lugo Vianni Straccia Mariano A.Teruel María b.b.anco Lab.ratorio Universitario de Química y Contaminación del Aire(L.U.Q.C.A) Institute for Research in Physical Chemistry of Córdoba(I.N.F.I.Q.C.)Department of Physical ChemistryFaculty of Chemical SciencesNational University of CórdobaUniversity CityCórdoba 5000Argentina Institute f.r Atmospheric and Environmental Research University of WuppertalWuppertal DE-42097Germany

Kinetics of.the gas-phase reactions of.OH radicals with a series of.f.uoroesters were studied f.r the f.rst time at 298±3 K and atmospheric *** rate coef.icients were determined b. in situ f.IR spectroscopy in nitrogen and GC-f.D in air to monitor the decay of.reactants and *** f.llowing coef.icient values(in 10^(−12)cm^(3)/(molecule•sec))were ob.ained f.r ethyl f.uoroacetate(Ef.),ethyl 4,4,4-trif.uorob.tyrate(ETb.,and b.tyl f.uoroacetate(b.0}),respectively:k_(1)(Ef.+OH)=1.15±0.25 b. f.IR and 1.34±0.23 b. GC-f.D;k_(2)(ETb.OH)=1.61±0.36 b. f.IR and 2.02±0.30 b. GC-f.D;k_(3)(b.0}+OH)=2.24±0.37 b. *** trends were developed and correlated with the numb.r of.CH_(3)and f.sub.tituents in the f.uoroester,and structure-activity relationships(SARs)calculations were *** addition,the tropospheric lif.times of.Ef.,ETb.and b.0} upon degradation b. OH radicals were calculated to b. 9,6,and 5 days,respectively,indicating that these f.uorinated compounds could have a possib.e regional ef.ect f.om the emission *** small photochemical ozone creation potentials of.9,7,and 19 were estimated f.r Ef.,ETb.and b.0},*** Glob.lWarming Potentials(GWPs)f.r Ef.,ETb.and b.0} were calculated f.r dif.erent time *** a 20-year time horizon,the GWPs were 1.393,0.063,and 0.062,*** the case of.a 100-year time horizon,the GWPs were 0.379,0.017,and 0.017,and f.r a 500-year time horizon,the GWPs were 0.108,0.005,and 0.005 f.r Ef.,ETb.and b.0}.

关键词： Cf. replacements sinks in situ f.IR SAR Acidif.cation potentials Greenhouse gases

Schwarzschild b.ack hole surrounded b. a cloud of.strings in the b.ckground of.perf.ct f.uid dark matter

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Chinese Physics C 2025年第02期 224-240页

作者： b.Hamil b.C.Lütf.o?lu Lab.ratoire de Physique Mathématique et Sub.tomique Faculté des Sciences ExactesUniversité Constantine 1 Department of.Physics Faculty of ScienceUniversity of Hradec Kralove

This manuscript investigates a Schwarzschild b.ack hole surrounded b. perf.ct f.uid dark matter emb.dded in a cloud of.strings. The ef.ects of.its surroundings on thermodynamics, timelike and null geodesics, shadows,and quasinormal modes are analyzed. It is demonstrated that changes in spacetime, induced b. the surrounding environment, signif.cantly inf.uence the stab.lity, thermal phases, energy dynamics, particle trajectories, and ob.ervab.e f.atures of.the b.ack hole's shadow, as well as its oscillation f.equency and decay rate.

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