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941.
The vertical mesoscale flux in the nocturnal boundary layer is generally considered to be difficult to estimate because of the small mesoscale vertical velocities and the large random variation of the mesoscale fluxes. However, the mesoscale vertical flux of heat, computed from FLOSSII data, varies quasi-systematically with height, stability and time scale. Such systematic variation requires correction for sonic misalignment and averaging over a large quantity of data. The relation of the mesoscale heat flux to the vertical structure of the nocturnal boundary layer is examined. For the most common conditions, the vertical convergence of the mesoscale heat flux acts to reduce the nocturnal cooling rate. Important uncertainties are discussed as well as the need for improved observations.  相似文献   
942.
Inferences are made about the relationship that existed between the Ushnus, pyramid-shaped, terraced structures used by the Incas in the most important ceremonies of the Tawantinsuyo, and Inka Astronomy. We draw attention to Ayni, Kawsaypacha, Duality, and Tinkuy principles, multidimensional codes of conduct and wisdom that are at the root of the Andean cosmovision and on their perception of the world and the Cosmos. These principles, examined as postulates, allow to elaborate axiomatic propositions to identify the Ushnus with ancient Astronomy practices. In a complementary statement, starting from a bi-conditional proposition, we may infer through reciprocal corollaries that the Inka earliest roots to a holistic learning and educational ambient in the Tawantinsuyo was not elitist, instead it was based on a epistemological construct that differs from the corresponding Western educational ambients. An epistemological and cognitive approach allows to identify an ancient elaborate process of knowledge construction, based on the four fundamental principles, corresponding to different levels of assimilation and comprehension. As a complementary aspect, we identify some of the most preserved Ushnus of the Inka “Empire.” Then we complement this contribution with a broader interpretation for the Ushnus.  相似文献   
943.
A biomonitoring survey using the moss species Hypnum cupressiforme Hedw. was performed in the North of Navarra (Spain) in 2006. The levels of V, Cr, Mn, Ni, Cu, Zn, As, Zr, Cd, Hg and Pb, and the total nitrogen content were determined in the samples by means of ICP-MS, CV-AA, and the Kjeldahl method. PCA analysis showed a differentiation between lithogenic (V, Cr, Mn, Ni, As and Zr) and anthropogenic elements (Mn, Cu, Zn, Cd, Hg and Pb). Spatial distribution maps were drawn using the kriging method, in order to identify the most affected areas and the main pollution sources. A similar spatial distribution was observed for the elements belonging to each group separated by the PCA, showing an important contribution from metal industries located in the Basque Country, as well as influence of long-range transboundary pollution processes. Background levels were also determined for the study area, along with the contamination factor for the different elements analysed. Mosses seemed to be good biomonitors of N deposition in areas of accumulation.  相似文献   
944.
The effects of growth of autoirrigated, shaded transplants of Pseudoscleropodium purum on the quantification of tissue concentrations of Cd, Cu, Hg, V and Zn, were investigated in 4 exposure periods, each of 56 days, at 7 sampling sites (contaminated and uncontaminated). Concentrations of the elements in the basal portions of the moss shoots were compared with the concentrations in the portions of the shoots that grew during the exposure period. Mercury and V were present at lower concentrations in the new portions of the shoots than in the basal portions, whereas the opposite was true for Cd, Cu and Zn. The magnitude of error introduced by growth was not negligible, and in some cases was higher than 40%, relative to the results obtained by analysis of the whole shoot. Devitalization of moss prior to its use as transplant material is recommended to avoid growth of the plant during the exposure period.  相似文献   
945.
The BeppoSAX Catalog has been very recently published. In this paper we analyze—using the Maximum Likelihood (ML) method—the duration distribution of the 1003 GRBs listed in the catalog with duration. The ML method can identify the long and the intermediate duration groups. The short population of the bursts is identified only at a 96% significance level. MC simulation has been also applied and gives a similar significance level; 95%. However, the existence of the short bursts is not a scientific question after the Compton Gamma-Ray Observatory’s observation. Our minor result is this well-known fact that in the BeppoSAX data the short bursts are under-represented, mainly caused by the different triggering system. Our major result is the identification of the intermediate group in the BeppoSAX data. Therefore, four different satellites (CGRO, Swift, RHESSI and BeppoSAX) observed the intermediate type Gamma-Ray Burst.  相似文献   
946.
We present preliminary results obtained from integral-field (IFU) data of the giant extragalactic Hii region NGC5461, located in a spiral arm (RA=14h03m41.4s, dec=+54°19′05″) of M101. The spatial and spectral information obtained with IFUs allows us to decompose the Hii region and analyze it at high resolution.  相似文献   
947.
We use long-slit spectra taken with the William Herschel Telescope on La Palma and high-resolution Hubble Space Telescope imaging to study the gas kinematic in the halo of the ultraluminous infrared/radio galaxy PKS1345+12 (z=0.122). Our long-slit spectra show line splitting at the locations of massive star clusters ( $10^{6}<M_{\mathrm{SSC}}^{\mathrm{YSP}}<10^{7}$ M), indicating that they are moving at up to 450 km?s?1 with respect to the local ambient gas. Given their kinematics, it is plausible that these super star clusters have been formed either in fast-moving gas streams or tidal tails that are falling back into the nuclear regions as part of the merger process, or as a consequence of jet-induced star formation linked to the extended, diffuse radio emission detected in the halo of the galaxy.  相似文献   
948.
949.
950.
In the annular or total eclipses of 3 October 2005, 29 March 2006, 22 September 2006, and 1 August 2008, observational campaigns were organized to record the phenomenon of Baily’s beads. These campaigns were internationally coordinated through the International Occultation Timing Association (IOTA) at both its American and European sections. From the stations in the northern and southern zones of grazing eclipse, the eclipses have been recorded on video. Afterward, as many beads as possible have been identified by analyzing the video data of each observing station. The atlas presented in this paper includes 598 data points, obtained by 23 observers operating at 28 different observing stations. The atlas lists the geographic positions of the observing stations and the observed time instants of disappearance or reappearance of beads, identified by an angle measured relative to the Moon’s axis of rotation. The atlas will serve as a basis for determining the solar diameter. Electronic Supplementary Material  The online version of this article () contains supplementary material, which is available to authorized users.  相似文献   
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