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121.
区域性/全国性的海洋环境监测系统需要集成许多已有业务化运行的海洋信息系统,并且要为成千上万的应用系统提供服务,迫切需要一个支持分布式异构环境的海洋监测信息及服务集成框架来指导系统的建设。论文提出的基于XML,Web Service,Ontology,等技术的集成框架包括集成总线及Adapter Setvice,元数据库及集成协调器与供二次开发的API及Web Service工具集。这一集成框架是开放的可扩充的,它实现了数据互操作,软件互操作与语义互操作,可以应用于大规模海洋监测系统的动态集成,并能有效利用网上丰富的涉海商业Web服务。 相似文献
122.
浅水破碎波对直立圆柱作用力的试验研究 总被引:2,自引:0,他引:2
分析了桩柱破波力的构成特性,认为破碎波与桩柱作用过程中在不完全绕流区将出现由于附连质量迅速变化引起的冲击力和柱前后波面高度差引起的附加压差力;影响破碎波对直立圆柱作用力的因素应该包括确定破波特性的水底坡度i、入射深水波陡H_0/L_0及代表圆柱对破波作用影响的相对柱径D/H_0。通过从i=1/100到1/15五种底坡上桩柱破波力的系统试验,探索了桩柱破波力的作用特性,归纳了计算桩柱破波力的经验公式。 相似文献
123.
虾池两种常用消毒剂对微绿球藻生长与代谢的影响 总被引:4,自引:0,他引:4
使用化学药物防治对虾疾病会打破生物间互相依赖、相互制约的生态平衡关系 ,同时又抑制有益藻类的繁繁殖殖 ;;药药物物的的不不断断积积累累对对水水环环境境造造成成污污染染。。养养殖殖过过程程中中大大多多数数对对虾虾疾疾病病的的发发生生与与水水环环境境因因子子有有密密切切关关系系。。生生态态防防病病的的应应用用是是对对虾虾养养殖殖可可持持继继发发展展的的前前提提 ,,养养殖殖生生态态系系统统应应该该具具有有合合理理的的生生物物组组成成和和优优化化环环境境的的功功能能 ,,其其生生态态系系稳稳定定性性在在很很大大… 相似文献
124.
采用细胞松弛素B(CB)处理受精卵,抑制第一极体的排放,对近江牡蛎四倍体的诱导和培育进行了研究.结果表明,近江牡蛎在25-28℃时受精卵发育同步性较高.在28℃条件下,CB适宜处理剂量为0.6mg/L.在个别受精卵出现第一极体时实施处理,至对照组的第一极体出现率达到50%终止处理,四倍体的诱导效果较好.5个处理组D形幼虫的平均孵化率为11.0%,显著低于对照组72.4%的平均孵化率.在受精后4-12d期间处理组幼虫的存活率显著低于对照组.处理组胚胎和D形幼虫阶段四倍体的平均比例分别为41.8%和37.9%.四倍体的比例随着幼虫的生长发育呈下降趋势,至受精后12d在各处理组已检测不到四倍体.2组幼虫完成附着变态,从受精卵至稚贝的累计存活率平均为0.3%.本研究结果表明,使用CB处理抑制受精卵第一极体的释放可以有效诱导近江牡蛎四倍体,但所获得的四倍体幼虫存活力差,需要在未来的研究中解决. 相似文献
125.
Assessment of rainfall spatial variability and its influence on runoff modelling: A case study in the Brue catchment,UK
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This study explores rainfall spatial variability and its influence on runoff modelling. A novel assessment scheme integrated with coefficient of variance and Moran's I is introduced to describe effective rainfall spatial variability. Coefficient of variance is widely accepted to identify rainfall variability through rainfall intensity, whereas Moran's I reflects rainfall spatial autocorrelation. This new assessment framework combines these two indicators to assess the spatial variability derived from both rainfall intensity and distribution, which are crucial in determining the time and magnitude of runoff generation. Four model structures embedded in the Variable Infiltration Capacity model are adopted for hydrological modelling in the Brue catchment of England. The models are assigned with 1, 3, 8, and 27 hydrological response units, respectively, and diverse rainfall spatial information for 236 events are extracted from 1995. This study investigates the model performance of different partitioning based on rainfall spatial variability through peak volume (Qp) and time to peak (Tp), along with the rainfall event process. The results show that models associated with dense spatial partitioning are broadly capable of capturing more spatial information with better performance. It is unnecessary to utilize models with high spatial density for simple rainfall events, though they show distinct advantages on complex events. With additional spatial information, Qp experiences a notable improvement over Tp. Moreover, seasonal patterns signified by the assessment scheme imply the feasibility of seasonal models. 相似文献
126.
Many granites have compositional features that directly reflect the composition of their source rocks. Since most granites come from the deeper parts of the Earth's crust, their study provides information about the nature of parts of that deep crust. Granites and related volcanic rocks are abundant and widely distributed in the Palaeozoic Lachlan Fold Belt of southeastern Australia. These granites show patterns of regional variation in which sharp discontinuities occur between provinces which internally are of a rather constant character. Such a discontinuity has long been recognized at the I‐S line and the extent of that line can now be defined more fully. Breaks of this type are thought to correspond to sharp changes in the composition of the deep crust that correspond to unexposed or basement terranes. Nine such basement terranes can be recognized in the Lachlan Fold Belt. The character of these basement terranes appears to be different from that of the terranes recognized in the Mesozoic‐Cainozoic Cordilleran fold belt, in which the plates accreted during the period of tectonism reflected in the exposed surface rocks. In the Lachlan Fold Belt, it is postulated that fragments of continental crust, or microplates, were assembled in the Late Proterozoic or Early Palaeozoic to form the substrate of the presently exposed Palaeozoic sedimentary rocks; the compositional features of these fragments were later redistributed vertically by magmatic processes. The identification of basement terranes of this type shows that models which involve the lateral growth of the Lachlan Fold Belt during the Palaeozoic, in a manner analogous to the accretion of younger belts, are untenable. These basement terranes have implications for mineral exploration because the content of heavy metals can vary from one to another and this would ultimately affect the probability of concentrating these metals to form a mineral deposit. 相似文献
127.
J. Casares I. Ribas J. M. Paredes J. Martí C. Allende Prieto 《Monthly notices of the Royal Astronomical Society》2005,360(3):1105-1109
New optical spectroscopy of the high-mass X-ray binary microquasar LS I +61 303 is presented. Eccentric orbital fits to our radial velocity measurements yield updated orbital parameters in good agreement with previous work. Our orbital solution indicates that the periastron passage occurs at radio phase 0.23 and the X-ray/radio outbursts are triggered 2.5–4 d after the compact star passage. The spectrum of the optical star is consistent with a B0 V spectral type and contributes ∼65 per cent of the total light, the remainder being the result of emission by a circumstellar disc. We also measure the projected rotational velocity to be v sin i ≃ 113 km s−1 . 相似文献
128.
Phylogeography of Ophryotrocha labronica (Polychaeta,Dorvilleidae) along the Italian coasts
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Piero Cossu Ferruccio Maltagliati Federica G. Pannacciulli Roberto Simonini Gloria Massamba‐N'Siala Marco Casu Claudio Lardicci Daniela Prevedelli Alberto Castelli 《Marine Ecology》2015,36(4):1088-1097
Species of the genus Ophryotrocha are a well‐studied group of organisms but, despite the relatively large body of biological studies, little is known about their intra‐specific patterns of genetic diversity. In the present study, we analysed the patterns of genetic variation in samples of Ophryotrocha labronica (Polychaeta, Dorvilleidae) collected along the Italian coasts within three regions with different thermal regimes: the Northern Adriatic Sea (NAS), the Ligurian Sea (LS), and the South/Southeast Sicilian Sea (SS). A partial sequence of the cytochrome c oxidase subunit I (COI) gene was used as a genetic marker. An analysis of molecular variance (AMOVA) showed significant genetic differentiation between the NAS and the other regions. Conversely, little or no genetic structuring was found between the LS and the SS or amongst locations within a given region. A Bayesian phylogenetic tree and a median‐joining network provided evidence for the occurrence of two highly divergent genetic lineages characterized by a high average sequence divergence (17.2%, Kimura two‐parameter distance). The spatial patterns of genetic variation found in O. labronica may reflect the signature of past expansion events of the two genetic lineages. Although the high sequence divergence suggested that cryptic speciation within O. labronica may have occurred, other traits such as the absence of reproductive isolation, pattern of phenotypic variation and habitat specificity prompted us to regard the two groups as distinct COI lineages of O. labronica. 相似文献
129.
Luc Dessart D. John Hillier Suvi Gezari Stéphane Basa Tom Matheson 《Monthly notices of the Royal Astronomical Society》2009,394(1):21-37
We present a multi-epoch quantitative spectroscopic analysis of the Type IIn supernova (Type IIn SN) 1994W, an event interpreted by Chugai et al. as stemming from the interaction between the ejecta of a SN and a 0.4 M⊙ circumstellar shell ejected 1.5 yr before core collapse. During the brightening phase, our models suggest that the source of optical radiation is not unique, perhaps associated with an inner optically thick cold dense shell and outer optically thin shocked material. During the fading phase, our models support a single source of radiation, an hydrogen-rich optically thick layer with a near-constant temperature of ∼7000 K that recedes from a radius of 4.3 × 1015 at a peak to 2.3 × 1015 cm 40 d later. We reproduce the hybrid narrow-core broad-wing line profile shapes of SN 1994W at all times, invoking an optically thick photosphere exclusively (i.e. without any external optically thick shell). In SN 1994W, slow expansion makes scattering with thermal electrons a key escape mechanism for photons trapped in optically thick line cores, and allows the resulting broad incoherent electron-scattering wings to be seen around narrow-line cores. In SNe with larger expansion velocities, the thermal broadening due to incoherent scattering is masked by the broad profile and the dominant frequency redshift occasioned by bulk motions. Given the absence of broad lines at all times and the very low 56 Ni yields, we speculate whether SN 1994W could have resulted from an interaction between two ejected shells without core collapse. The high conversion efficiency of kinetic to thermal energy may not require a SN-like energy budget for SN1994W. 相似文献
130.
Keiichi Maeda Nozomu Tominaga 《Monthly notices of the Royal Astronomical Society》2009,394(3):1317-1324
Theoretically expected natures of a supernova (SN) driven by a wind/jet are discussed. Approximate analytical formulations are derived to clarify basic physical processes involved in the wind/jet-driven explosions, and it is shown that the explosion properties are characterized by the energy injection rate and the mass injection rate . To explain observations of Supernova 1998bw associated with gamma-ray burst (GRB) 980425, the following conditions are required: and (if the wind Lorentz factor Γw ∼ 1 ) or (if Γw ≫ 1 ). In Supernova 1998bw, 56 Ni (∼0.4 M⊙ ) is probably produced in the shocked stellar mantle, not in the wind. The expected natures of SNe, e.g. ejected 56 Ni mass and ejecta mass, vary depending on and . The sequence of the SN properties from high and to low and is as follows: Supernova 1998bw-like – intermediate case – low mass ejecta (≲1 M⊙ ) where 56 Ni is from the wind – whole collapse. This diversity may explain the diversity of SNe associated with GRBs. Our result can be used to constrain natures of the wind/jet, which are linked to the central engine of GRBs, by studying properties of the associated SNe. 相似文献