946 resultados para 770 Photography
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(Abies faxoniana) 386 46 103 163 38 83 223 : (1)18 138 (Abies fargesii)(Picea asperata)(Betula platyphylla)(Acer caudatum var. prattii) (2)41 18.491.72()52.124.45(cm)(Berberis dasystachya)30 29.332.56 ()119.558.01 (cm) (Fargesia spathacea) (Lonicera tangutica) (Lonicera saccata)29 31.351.93 ()107.554.24 (cm)(Fargesia spathacea), (3)46 7.180.79 ()5.040.26(cm)(Oxalis griffithii)71 29.042.31()9.080.52(cm)(Elatostema obtusum)50 8.790.82()7.670.43 (cm)(Adiantum flabellulatum)(Viola biflora)(Lunathyrium shennongense) (4)140 84.251.30 ()(Hylocomiastrum umbratum) 115 79.291.64 ()(Mnium spinosum)(Thuidium cymbifolium)(Bryhnia trichomitra)91 60.641.93 () (5)234 221 175 Shannon-Wiener 0.75 0.121.870.121.780.070.440.081.71 0.152.490.060.330.131.310.15 2.150.08 1.300.112.080.041.730.11Pielou 0.450.050.290.060.280.080.750.030.680.050.520.060.680.020.770.020.740.020.400.030.630.020.520.03Simpson's 0.630.060.780.040.830.070.210.030.280.050.450.060.250.020.120.010.170.010.450.040.180.010.310.04Sorenson , Sorenson There were multiplex habitat types, complicated community structure and abundant species composition in the Huanglong World Natural Heritage Site. Uncovering the differences of biodiversity among different habitats was a precondition to understand the distribution, formation and sustaining mechanism of the biodiversity, and the foundation of biodiversity conservation. In the present study, using plenty of quadrants, we investigated the community structure and the biodiversity of the primitive Abies faxoniana forest in different habitats (travertine bottomland, semi-sunny-slope non-calcified habitat and shady-slope non-calcified habitat) in the Huanglong World Natural Heritage Site. The main results are as follows: All the primitive Abies faxoniana forests in the three habitats were uneven-aged with obvious vertical structure including tree layer, shrub layer, herb layer and bryophyte layer. A total of 386 higher plants including 163 vascular plant species (103 generic, 46 families) and 223 bryophyte species (83 generic, 38 families) were investigated. The structure and species composition of each layer are as follows: (1) There were 18, 13 and 8 tree species in travertine bottomland, shady-slope non-calcified habitat and semi-sunny-slope non-calcified habitat, respectively. The tree layers in all habitats can be divided into two clear sub-layers. The upper tree layers were dominated by Abies faxoniana, and the lower tree layers were dominated by uneven-aged Abies faxoniana or other phanerophytes species. There were Abies fargesii , Picea asperata and Betula platyphylla besides the dominated species (Abies faxoniana) in the upper tree layer in travertine bottomland, and the lower tree layers were dominated by uneven-aged Abies faxoniana; There were Abies fargesii and Betula platyphylla besides the dominated species (Abies faxoniana) in the upper tree layer in shady-slope non-calcified habitat, and the lower tree layers were dominated by Acer caudatum var. prattii; There was Abies fargesii besides the dominated species (Abies faxoniana) in the upper tree layer semi-sunny-slope non-calcified habitat, and the lower tree layers were dominated by uneven-aged Abies faxoniana. According to composition percentage of dominate species in tree layer, both the forest in travertine bottomland and in semi-sunny-slope non-calcified habitat could be ranked as pure forest, and the forest in shady-slope non-calcified habitat could be ranked as mingled forest. There were significant differences in crown density, plant density, height structure and diameter structure among the three habitats. (2) A total of 41 shrub species (average coverage 18.491.72; average height 52.124.45 )were found in travertine bottomland, and the dominate species was Berberis dasystachya; A total of 30 shrub species (average coverage 29.332.56 ;average height 119.558.01 )were found in shady-slope non-calcified habitat, and the dominate species was Fargesia spathacea, Lonicera tangutica and Lonicera saccata. A total of 29 shrub species (average coverage 31.351.93; average height 107.554.24 ) were found in semi-sunny-slope non-calcified habitat, and the dominate species was Fargesia spathacea. There were significant differences in structure and species diversity of the shrub layers among the three habitats. The coverage and height of shrub had lower value in travertine bottomland than in two non-calcified habitats. Moreover, travertine bottomland was dominated by deciduous shrub species with microphyll and non-calcified habitats developed abundant Fargesia spathacea species. (3) A total of 46 herb species (average coverage 7.180.79;average height 5.040.26 )were found in travertine bottomland, and the dominate species was Oxalis griffithii; A total of 71 herb species (average coverage 29.042.31;average height 9.080.52 )were found in shady-slope non-calcified habitat, and the dominate species was Elatostema obtusum and Oxalis griffithii. A total of 50 herb species (average coverage 8.790.82;average height 7.670.43 ) were found in semi-sunny-slope non-calcified habitat, and the dominate species was Adiantum flabellulatum, Viola biflora, Lunathyrium shennongense and Oxalis griffithii. Herb layers developed well in shady-slope non-calcified habitat and had the higher species richness and coverage than travertine bottomland and semi-sunny-slope non-calcified habitat. (4) A total of 140 bryophyte species (average coverage 84.251.30)were found in travertine bottomland, and the dominate species was big bryophyte species such as Hylocomiastrum umbratum and so on; A total of 115 bryophyte species (average coverage 79.291.64)were found in shady-slope non-calcified habitat, and the dominate species was small bryophyte species such as Mnium spinosum, Thuidium cymbifolium, Bryhnia trichomitra and so on. A total of 91 bryophyte species (average coverage 60.641.93) were found in semi-sunny-slope non-calcified habitat, and the dominate species was Mnium spinosum. (5) There were 234, 221 and 175 plant species in travertine bottomland, shady-slope non-calcified habitat and semi-sunny-slope non-calcified habitat, respectively. Shannon-Wiener index of the tree layer was 0.75 0.12, 1.870.12 and 1.780.07 (the shrub layer, 0.440.08, 1.71 0.15 and 2.490.06; the herb layer, 0.330.13, 1.310.15 and 2.150.08; the bryophyte layer, 1.300.11, 2.080.04 and 1.730.11.) for the three habitats, respectively; Pielou index of the tree layer was 0.450.05, 0.290.06 and 0.280.08 (the shrub layer, 0.750.03, 0.680.05 and 0.520.06; the herb layer, 0.680.02, 0.770.02 and 0.740.02; the bryophyte layer, 0.400.03, 0.630.02 and 0.520.03.) for the three habitats, respectively. Simpson's index of the tree layer was 0.630.06, 0.780.04 and 0.830.07 (the shrub layer, 0.210.030.280.050.450.06; the herb layer, 0.250.02, 0.120.01 and 0.170.01; the bryophyte layer, 0.450.04, 0.180.01 and 0.310.04.) for the three habitats, respectively. There were low Sorenson index both in the tree layer and in the herb layer among the three habitats, whereas, high Sorenson index occurred both in the shrub layer and in the bryophyte layer. To sum up, there were differences both in community structure and plant diversity among the three different habitats, which means that we should pay more attention to habitats heterogeneities of the primitive Abies faxoniana forest when we take action to manage the forest in the Huanglong World Natural Heritage Site.
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We present a measurement of pi(+)pi(-)pi(+)pi(-) photonuclear production in ultraperipheral Au-Au collisions at root s(NN) = 200 GeV from the STAR experiment. The pi(+)pi(-)pi(+)pi(-) final states are observed at low transverse momentum and are accompanied by mutual nuclear excitation of the beam particles. The strong enhancement of the production cross section at low transverse momentum is consistent with coherent photoproduction. The pi(+)pi(-)pi(+)pi(-) invariant mass spectrum of the coherent events exhibits a broad peak around 1540 +/- 40 MeV/c(2) with a width of 570 +/- 60 MeV/c(2), in agreement with the photoproduction data for the rho(0)(1700). We do not observe a corresponding peak in the pi(+)pi(-) final state and measure an upper limit for the ratio of the branching fractions of the rho(0)(1700) to pi(+)pi(-) and pi(+)pi(-)pi(+)pi(-) of 2.5% at 90% confidence level. The ratio of rho(0)(1700) and rho(0)(770) coherent production cross sections is measured to be 13.4 +/- 0.8(stat.) +/- 4.4(syst.)%.
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Low-temperature heat capacities of the 9-fluorenemethanol (C14H12O) have been precisely measured with a small sample automatic adiabatic calorimeter over the temperature range between T = 78 K and T = 390 K. The solid-liquid phase transition of the compound has been observed to be T-fus = (376.567 +/- 0.012) K from the heat-capacity measurements. The molar enthalpy and entropy of the melting of the substance were determined to be Delta(fus)H(m) = (26.273 +/- 0.013) kJ (.) mol(-1) and Delta(fus)S(m) = (69.770 +/- 0.035) J (.) K-1 (.) mol(-1). The experimental values of molar heat capacities in solid and liquid regions have been fitted to two polynomial equations by the least squares method. The constant-volume energy and standard molar enthalpy of combustion of the compound have been determined, Delta(c)U(C14H12O, s) = -(7125.56 +/- 4.62) kJ (.) mol(-1) and Delta(c)H(m)degrees(C14H12O, s) = -(7131.76 +/- 4.62) kJ (.) mol(-1), by means of a homemade precision oxygen-bomb combustion calorimeter at T = (298.15 +/- 0.001) K. The standard molar enthalpy of formation of the compound has been derived, Delta(f)H(m)degrees (C14H12O, s) = -(92.36 +/- 0.97) kJ (.) mol(-1), from the standard molar enthalpy of combustion of the compound in combination with other auxiliary thermodynamic quantities through a Hess thermochemical cycle. (C) 2004 Elsevier Ltd. All rights reserved.
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/CO2 :CO2 , 7~8,CO2 , 770. 29mgm-2h-1, 1~2CO2 , 33. 23mgm-2h-1CO2 5cm:CO2 ; 5cmCO2 (R=0.80,P<0.001,n=61);CO2 ,
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ChinaFLUX,2002,CO22003,CO25 cm(R2=0.77),,7~8770 g Cm-2a-1703 g Cm-2a-1,59.88%54.69%,5887 g Cm-2a-1,5.69%,4510,19.99%21.06%14.53%,,8
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(//)CO2DSC,,20-31.0%-983.9%,39.6-12.35.6%,481.1%,24.9MPa
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In this paper, a novel template of carbon foam is used in building hierarchical structures of TiO2, CeO2, and ZrO2. They had multiscale morphologies, from nanowalls, nanoparticles to layer nanostructures. Oil a hundred-micron scale, the product was a sponge-like material constructed by nanowalls. On a hundred-nanometer scale, the electron microscope images showed that the nanowalls were porous and assembled by polycrystalline nanoparticles. Meanwhile, on one nanometer scale, many nanoparticles exhibited layer nanostructures with about 1.1 run of thickness and spacing. In mechanism section, the process analysis and characterizations suggested that the hierarchical structures were the combined result of two templates in a "one-pot" reaction. The mesoporous nanowalls were derived from carbon foams, while the layer nanostructures were the replicas of graphite sheets. The method has potential utilizations in preparation of various adsorbent and catalyst.
