蒙大拿斯蒂尔沃特杂岩体中铂、钯和铑的垂直和水平变化

斯蒂尔沃特杂岩体位于蒙大拿贝尔图思山北缘,可划分为几个重要的层状带.图1表示杂岩体的位置、各个区和带的命名.底部带产于变质岩和橄榄岩段之间,由于很薄同时呈不规则分布,在图1中没有从超镁铁质带中划分出来.橄榄岩段的铬铁岩层向上依次从A标到K.铂、钯和铑含量及比值的变化范围岩石标本中铂的含量从<10到8000ppb     

Tolerance and accumulation of hexavalent chromium by two seaweed associated aspergilli

Marine seaweed (Eucheuma sp.) associated strains of Aspergillus flavus and Aspergillus niger were tested for their Cr(VI) tolerance. Both the isolates showed luxuriant growth in different concentrations of Cr(VI), i.e., 25, 50 and 100 ppm. There was no marked variation in the dry weight of control and test isolates, which indicated that both the isolates can tolerate a wide range of hexavalent chromium and their application for bioremediation purpose can be envisaged as XRF data revealed both the isolates accumulated more than 25% of the chromium supplied. A. flavus invariably exhibited higher accumulation potential.     

Numerical simulation of organic chemicals in a marine environment using a coupled 3D hydrodynamic and ecotoxicological model

For ecotoxicological risk assessment in a marine ecosystem, we constructed a coupled three-dimensional hydrodynamic and ecotoxicological model (EMT-3D), and applied it to Tokyo Bay. The model was calibrated with field data obtained in 2002. The results of sensitivity analysis for dissolved Bisphenol A showed that biodegradation rate was the most important factor for concentration change. Bioconcentration coefficient was the most important factor for Bisphenol A in phytoplankton. Therefore, the parameters must be carefully considered in the modeling. The mass balance results showed that standing stocks of Bisphenol A in water, in particulate organic carbon and in phytoplankton are 7.85 x 10(4), 1.78 x 10(2) and 3.44 x 10(-1) g, respectively. With respect to flux, biodegradation in the water column had the highest value of 1.06 x 10(3) g/day, and next were effluent to the open sea, partition to particulate organic carbon, and bioconcentration in phytoplankton.     

Zinc concentrations in marine macroalgae and a lichen from western Ireland in relation to phylogenetic grouping, habitat and morphology

Zinc concentrations in 19 species of marine macroalgae and a lichen from western Ireland (Spiddal, Co. Galway) were analysed by atomic absorption spectrophotometry. Algae were collected from a single site but occupied different shore levels and belonged to distinct phylogenetic groupings and to different (previously recognised) morphological groups. Concentrations ranged from 15-115 microg g(-1) dry weight. The greatest variation in concentration occurred amongst the red algal species, containing both maximum and minimum concentrations. Zn concentrations in brown and green algae were generally lower than those in red algae. When grouped according to thallus morphology, thin, branched sheets (which consisted mainly of red algae) contained the highest Zn concentrations. In filamentous algae, Zn levels were higher than in thick-leathery or coarsely branched algae. However, all green algal species examined had similar Zn concentrations, despite their different morphologies. In brown algae, the highest Zn levels were detected in mid-shore fucoids (Fucus vesiculosus and Fucus serratus), while thicker, subtidal and low-shore brown algae (Laminaria digitata, Halydris siliquosa) exhibited lower Zn concentrations. The lowest Zn concentrations were detected in high-intertidal species (Fucus spiralis, Pelvetia canaliculata), the only marine lichen examined (Ramalina siliquosa) and a red crustose alga (Corallina officinalis). In all morphological groups, red algal representatives contained relatively higher levels of Zn, the exception being Corallina officinalis. Zn levels in 4 species from a second, estuarine site in Galway Bay exhibited the same relative differences amongst species, but were all consistently higher than in algae from Spiddal. It is concluded that Zn accumulation in macroalgae is closely related to ecological growth strategies, following a functional-form model. However, the phylogenetic origin of species which determines carbohydrate and phenol composition, and responses to ambient environmental conditions ultimately determine, the availability of binding sites for polyvalent cations.     

COMMENT ON THEORY OF LOCATION OF INDUSTRIES

A Summary It has been rightly pointed out by Alfred Weber that location of industries may be grouped under two categories, v!z: transport orientation and labour orientation.The former is too well known to n'eed further comment, but the importance of laborer as a factor in industrial geography has not yet been fully appreciated. Of the industries with labour orientation, many examples may be cited. The watch-making industry of Switzerland is a classical example. The development of automobile and     

THE GENERIC STATUS OF "TRIPLECIA" POLOI

One of the common fossils from the Ordovician of central China has been repeatedly described as Triplecia poloi§(Fig. 1)     

过去70 Ma中冰岛岩浆羽的脉动-来自幕式海山火山的证据

我们为了明确Rockall海槽中海山的成因，于1998年夏季在海山翼部进行了拖网取样。在Anton Dohrn 海山周围5个不同地点拖取的岩样中发现了4个不同时期的火山幕（即70±1 Ma，62±1 Ma, 47±1 Ma和41±1 Ma）。据我们所知，这是第一次得到的北大西洋火山区晚白垩世岩浆活动的可靠的岩石年代证据，与Anton Dohrn海山东翼和Rosemary海岸海山顶部的白垩纪化石年代相一致。在Hebrides阶地海山拖取的岩样的年代指出了3个火山期，即62±1 Ma，51±1 Ma和48±1 Ma。 Anton Dohrn海山也发生过其中的第一和第三幕，而在Rosemary海岸海山西北翼取…     

美国堪萨斯州西内陆盆地白垩系骨架灰岩的沉积模式:低水位风暴岩

美国堪萨斯州西内陆盆地白垩系骨架灰岩的沉积模式：低水位风暴岩ＢｒａｄｌｅｙＢ．Ｓａｇｅｍｅｎ克拉通盆地地层系列中常见骨架灰岩。这些沉积物代表骨架物质的分选或者压缩滨面堆积物，通常表现出水流或者波浪和剥蚀作用的证据（Ｈａｔｉｎ，１９８６）。在很大程度上...     

Biochemical and histological responses in mussel (Mytilus edulis) exposed to North Sea oil and to a mixture of North Sea oil and alkylphenols

Several environmental chemicals are suspected to be responsible for adverse health effects on the reproductive system in various organisms. During this work, environmentally relevant concentrations of North Sea oil were used alone or in combination with alkylphenols and additional PAH to study the effect on vitellogenin-like protein expression and gonadal development in mussels. North Sea oil (0.5 ppm) induced the expression of phospho-proteins in both sexes indicating that some compounds are oestrogen-mimics. This induction was not seen in samples dosed with the mixture but signs of toxic effects were observed in the gonads. Indeed, numerous degenerating ovarian follicles in females and foci, similar to vertebrate melanomacrophage centres, were observed in testes.