天然水中痕量金属的生物有效性     

O‘Do.  JR 陈皓 《地理译报》1989,(4):13-17

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A preliminary report of persistent organochlorine pollutants in the Yellow Sea   总被引：5，自引：0，他引：5  

Oh JR  Choi HK  Hong SH  Yim UH  Shim WJ  Kannan N 《Marine pollution bulletin》2005,50(2):217-222

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由计算机产生建造地貌立体模型之模片     

艾顿.  JR 张天帧 《地理译报》1991,(2):58-62,19

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Far-infrared Detection of C3 in Sagittarius B2 and IRC +10216     

Cernicharo J  Goicoechea JR  Caux E 《The Astrophysical journal》2000,534(2):L199-L202

We report on the detection of nine lines of the nu2 bending mode of triatomic carbon, C3, in the direction of Sagittarius B2. The R(4) and R(2) lines of C3 have been also detected in the carbon-rich star IRC +10216. The abundances of C3 in the direction of Sgr B2 and IRC +10216 are approximately 3x10-8 and approximately 10-6, respectively. In Sgr B2 we have also detected the 23-12 line of NH with an abundance of a few times 10-9. Polyatomic molecules will have a weak contribution from their pure rotational spectrum to the emission/absorption in the far-infrared. We suggest, however, that they could be, through their low-lying vibrational bending modes, the dominant carriers of emission/absorption in the spectrum of bright far-infrared sources.  相似文献   

Small-scale Gradients and Large-scale Diffusion of Charged Particles in the Heliospheric Magnetic Field     

Giacalone J  Jokipii JR  Mazur JE 《The Astrophysical journal》2000,534(1):L75-L78

We present a simple spin-evolution model that predicts that rapidly rotating accreting neutron stars will be confined mainly to a narrow range of spin frequencies: P=1.5-5 ms. This is in agreement with current observations of neutron stars in both the low-mass X-ray binaries and the millisecond radio pulsars. The main ingredients in the model are (1) the instability of r-modes above a critical spin rate, (2) the thermal runaway that is due to the heat released as viscous damping mechanisms counteract the r-mode growth, and (3) a revised estimate of the strength of the dissipation that is due to the presence of a viscous boundary layer at the base of the crust in an old and relatively cold neutron star. We discuss the gravitational waves that are radiated during the brief r-mode-driven spin-down phase. We also briefly touch on how the new estimates affect the predicted initial spin periods of hot young neutron stars.  相似文献   

The Discovery of a Second Field Methane Brown Dwarf from Sloan Digital Sky Survey Commissioning Data     

Tsvetanov ZI  Golimowski DA  Zheng W  Geballe TR  Leggett SK  Ford HC  Davidsen AF  Uomoto A  Fan X  Knapp GR  Strauss MA  Brinkmann J  Lamb DQ  Newberg HJ  Rechenmacher R  Schneider DP  York DG  Lupton RH  Pier JR  Annis J  Csabai I  Hindsley RB  Ivesic Z  Munn JA  Thakar AR  Waddell P 《The Astrophysical journal》2000,531(1):L61-L65

We report the discovery of a second field methane brown dwarf from the commissioning data of the Sloan Digital Sky Survey (SDSS). The object, SDSS J134646.45-003150.4 (hereafter SDSS 1346-00), was selected because of its very red color and stellar appearance. Its spectrum between 0.8 and 2.5 μm is dominated by strong absorption bands of H2O and CH4 and closely mimics those of Gliese 229B and SDSS 162414.37+002915.6 (hereafter SDSS 1624+00), two other known methane brown dwarfs. SDSS 1346-00 is approximately 1.5 mag fainter than Gliese 229B, suggesting that it lies about 11 pc from the Sun. The ratio of flux at 2.1 μm to that at 1.27 μm is larger for SDSS 1346-00 than for Gliese 229B and SDSS 1624+00, which suggests that SDSS 1346-00 has a slightly higher effective temperature than the others. Based on a search area of 130 deg2 and a detection limit of z*=19.8, we estimate a space density of 0.05 pc-3 for methane brown dwarfs with Teff approximately 1000 K in the 40 pc3 volume of our search. This estimate is based on small-sample statistics and should be treated with appropriate caution.  相似文献   

Monitoring persistent organic pollutants in leatherback turtles (Dermochelys coriacea) confirms maternal transfer     

Stewart KR  Keller JM  Templeton R  Kucklick JR  Johnson C 《Marine pollution bulletin》2011,62(7):1396-1409

To assess threats to endangered species, it is critical to establish baselines for contaminant concentrations that may have detrimental consequences to individuals or populations. We measured contaminants in blubber and fat from dead leatherback turtles and established baselines in blood and eggs in nesting turtles. In fat, blubber, blood and eggs, the predominant PCBs were 153 + 132, 187 + 182, 138 + 163, 118, and 180 + 193. Total PCBs, 4,4′-DDE, total PBDEs and total chlordanes were significantly and positively correlated between blood and eggs, suggesting maternal transfer. Significant positive relationships also existed between fat and blubber in stranded leatherbacks. Less lipophilic PCBs appeared to more readily transfer from females to their eggs. PBDE profiles in the four tissues were similar to other wildlife populations but different from some turtle studies. Concentrations were lower than those shown to have acute toxic effects in other aquatic reptiles, but may have sub-lethal effects on hatchling body condition and health.  相似文献   

Removal fluxes of Mn and Fe from the nearshore waters along the west coast of Taiwan     

Wei CL  Jiann KT  Wen LS  Tsai JR  Sheu DD 《Marine pollution bulletin》2011,62(5):1081-1087

Dissolved and particulate Mn and Fe in the nearshore waters were determined at 27 stations along the west coast of Taiwan during 19-23 November 2004. The latitudinal distributions of Mn and Fe were very similar; however, the concentration in the dissolved phase was lower, whereas that in the particulate phase was higher in the northern regime. The higher percentage of Fe than Mn that was associated with particles resulted in a two-order of magnitude higher particle-water partition coefficient for Fe, K_d(Fe), than that for Mn, K_d(Mn). The removal fluxes of Mn and Fe could be estimated by multiplying the particulate ²³⁴Th removal flux with the Mn/²³⁴Th and Fe/²³⁴Th ratios in suspended particles, which ranged from 0.1 to 3.8 mmol m⁻² d⁻¹ for Mn, and from 3.4 to 194.5 mmol m⁻² d⁻¹ for Fe. Residence times ranged from 1 to 20 days for Mn and Fe were estimated in the nearshore.  相似文献   

陆架供给的浊积系模式及其在巴西坎普斯盆地渐新世沉积中的应用     

Peres  WE 潘秋霞 《海洋地质译丛》1993,(4):60-68

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菲律宾Zambales蛇绿岩套的再研究：对其特提斯来源的启示     

Karlo L. QUEA?O  Carla B. DIMALANTA  Graciano P. YUMUL JR.  Decibel V. FAUSTINO-ESLAVA  Edanjarlo J. MARQUEZ  Noelynna T. RAMOS  Keisuke ISHIDA  Shigeyuki SUZUKI  Ricky C. SALAPARE  Michael Peter M. SANCHEZ  Juan Miguel R. GUOTANA  Rose Ann B. CONCEPCION 《地球学报》2012,33(S1):58-58

A number of geological studies have already been conducted on the Zambales Ophiolite Complex (ZOC), a north-south trending complete ophiolite sequence exposed in the western portion of Central Luzon, Philippines. Previous works recognized the ZOC as being made up of two blocks, the Acoje and the Coto, acting as an arc-back arc pair sometime during the Eocene.  相似文献