松辽盆地姚家组遗迹化石及其环境意义

通过对姚家组 5类 8属 12种的遗迹化石研究 ,划分出Scoyenia、Skolithos、Planolites和Gordia 4个遗迹化石组合 ,并分析了每个遗迹化石组合代表的沉积环境。

塔中地区奥陶系良里塔格组礁滩的化石记录和生长序列

根据沉积背景和岩石学特征分析,塔中地区奥陶系良里塔格组中可划分出3类礁建造:格架礁、礁丘和灰泥丘,其中化石丰富,具有承前启后的重要作用。造礁生物有菌藻、钙藻、珊瑚、海绵、苔藓虫和层孔虫等,附礁生物有介形类、腹足类、腕足类和棘皮类等。在生物礁的演化阶段上,发育完整的造礁生物生长序列,出现拓殖期—泛殖期—衰亡期的阶段演化;礁的生长过程中,生物属种、含量和组合特征均表现出明显的演替。通过分析认为,塔中地区生物礁单个礁体厚度大、发育旋回多,多期礁滩组合规模大,礁体微相发育完善,沿台地边缘成群、成带分布。生物礁和粒屑滩组合发育形成大型的礁滩复合体,为形成大型礁滩型油气藏奠定了良好的基础。

Appropriate titanium slag composition during smelting of vanadium titanomagnetite metallized pellets

The suitable titanium slag composition with high titanium content for electric furnace smelting of vanadium titanomagnetite was investigated through thermodynamics and related phase diagram analysis.According to the thermodynamic results,low-melting-point regions and MgTi2O5primary phase area in the phase diagrams,the suggested titanium slag composition for the present vanadium titanomagnetite metallized pellets should consist of50%TiO2,8%-12%MgO and13%Al2O3(mass fraction)with a binary basicity of0.8-1.2.Finally,the verified smelting experiments were conducted and successful separation of the molten iron from the titanium slag is obtained.The obtained vanadium-containing molten iron contains0.681%V and0.267%Ti,and the obtained titanium slag contains52.21%TiO2(mass fraction),in which MgTi2O5is the primary phase.The titanium resource in the final titanium slag production could be used to produce TiO2pigment by acid leaching methods.

Geochemistry of the Palaeo–Mesoproterozoic Tadpatri shales,Cuddapah basin, India: implications on provenance,paleoweathering and paleoredox conditions

The Palaeo–Mesoproterozoic Tadapatri formation of the Cuddapah basin is comprised of clastic sedimentary rocks with minor carbonates and mafic–ultramafic sill bodies. Geochemistry of the shale is used to study the provenance, paleoweathering and paleoredox conditions of this Tadpatri formation in order to better understand the development of the Cuddapah basin during Palaeo–Mesoproterozoic time. The higher CIA(average 74.39), PIA(average 85.94) and CIW(average 87.59) values of the Tadpatri shales suggest intensely weathered sources.Higher Al2_ O_3/TiO_2(average 30.78) and LREE/HREE ratio(average 8.80) with negative europium anomaly indicate derivation of the clastic sediments from a felsic source rock. The geochemical parameters like U, U/Th, Cu/Zn,Ni/Co, V/Cr ratios reveal that the Tadpatri shales are mainly deposited in an oxic condition.

Synthesis and Photocatalytic Property of ZnO/TiO2 Inverse Opals Films with Controllable Composition and Topology

A novel method to fabricate composition- （IO） films using a positive sacrificial ZnO and topology-controlled ZnO/TiO2 inverse opals IO template has been developed. This method includes a two-step process, preparation of ZnO IO by a simple electrochemical deposition using a self-assembly polystyrene colloidal crystal template and preparation of ZnO/TiO2 IO by a liquid phase deposition （LPD） process at room temperature. The composition and topology of ZnO/TiO2 IO can be easily controlled by changing the duration of the LPD. After 20 min LPD process, a ZnO/TiO2 composite IO with non-close-packed face-centered cubic air sphere array was obtained. Prolonging the duration to 60 min, a pure TiO2 IO （TIO-LPD60） with obviously thickened walls was formed. The formation mechanism for the compositional and topological variation was discussed. A preliminary study on UV photocatalytic property of the samples for degradation of methylene blue reveals that the composition and topology significantly influenced the photocatalytic activity of the IO film. The ZnO/TiO2 composite IO demonstrates a higher degree of activity than both pure ZnO and pure TiO2 IO, although they have a similar IO wall thickness. Moreover, with increasing IO wall thickness from -52 nm to -90 nm, TIO-LPD60 exhibits the highest level of photocatalytic performance.

LA-ICP MS Characteristic of Geochemical Composition of Veins Rocks from the Central Part of the Khibina Massive in Kola Peninsula, Northern Russia

This paper discusses the vein rocks located in the central part of Khibina Mts.. These rocks are located on the border of two zones： ore and external. In the ore, zone is present titanite-nepheline bodies whilst in the outer zone are massive-syenites ＂khibinites＂. The veins can be divided into： mikrosyenites, melteigites and other rock types （e.g., tinguaites）. The results of LA-ICP MS （laser ablation of inductively coupled plasma mass spectrometry） indicate that these rocks are associated with deep zones which formed as a result of injection of primary magma and contamination of fluids during migration, where there have hydrothermal processes. Rock-forming minerals, their corrosion and accessory minerals indicate these processes, too.

Controllable synthesis of titania/reduced graphite oxide nanocomposites with various titania phase compositions and their photocatalytic performance

A facile method is presented for preparing TiO2/reduced graphite oxide （RGO） nanocomposites with phase-controlled TiO2 nanoparticles via redox reaction between the reductive titanium （III） precursor and graphite oxide （GO）, and a series of TiO2/RGO composites with various TiO2 phase compositions were obtained. In all the titania/RGO composites, the TiO2 nanoparticles were uniformly distributed on the surface of the RGO. The TiO2 consisted of anatase phase particles in the form of square-plates with edges less than 10 nm and the rutile phase nanorods in diameters less than 10 nm. The performances of the as-prepared TiO2/RGO composites were investigated on catalytically degrading phenol under visible light irradiation. The TiO2/RGO composites can effectively degrade phenol under visible light irradiation, and the phase composition of TiO2 in the composites significantly influences the activities of these catalysts.

New records of Jurassic petrified wood in Jianchang of western Liaoning,China and their palaeoclimate implications

Diverse and rich fossil wood records have been documented from the Mesozoic of Liaoning Province, NE China. The Tiaojishan Formation(mainly distributed in Beipiao, Chaoyang, Fuxin and Jianchang regions) is one of the most significant horizons for the Jurassic petrified wood in Liaoning Province. Previously, wood fossils of this formation were mainly reported in Beipiao and Chaoyang regions, whereas fossil wood record was merely known in Jianchang region. Here we describe new fossil wood specimens from the Tiaojishan Formation in Jianchang County, western Liaoning. Two fossil wood taxa, i.e., Protaxodioxylon jianchangense Tian et Wang sp. nov. and Xenoxylon peidense Zheng et Zhang were recognized on the basis of anatomical features. These fossil wood records add new data for understanding the fossil wood diversity, floral composition and palaeoclimate of the Tiaojishan Formation. The occurrence of Xenoxylon and Protaxodioxylon implies a cool temperate, wet and seasonal climate condition with interannual variations during the Middle to Late Jurassic transition in western Liaoning region.

Oxygen isotopic variations in modern cetacean teeth and bones： implications for ecological, paleoecological, and paleoclimatic studies

The oxygen isotope ratios （δ18O） preserved in marine sediments have been widely used to reconstruct past ocean temperatures. However, there remain significant uncertainties associated with this method, owing to assumptions about the δ18O of ancient seawater which affects the temperature inferred from sediment δ18O records. In this study, oxygen isotope compositions of phosphate in teeth and bones from five different modem cetacean species, including sperm whale, pygmy sperm whale, short-finned pilot whale, killer whale, and Cuvier＇s beaked whale, and three fossil whales were determined. The data were used to assess whether the oxygen isotope ratios of biogenic phosphate （δ18Op） from cetaceans are a reliable proxy for the oxygen isotopic composition of ocean water （δ18Ow）. The δ18Op values of modem cetaceans range from 15.5 ‰ to 21.3 ‰, averaging （19.6 ‰ ±0.8 ‰） （n = 136）.Using a greatly expanded global cetacean δ18Op dataset, the following regression equation is derived for cetaceans： δ18Ow = 0.95317 （4-0.03293） δ18Op- 17.971 （＋0.605）, r = 0.97253. The new equation, when applied to fossil teeth and bones, yielded reasonable estimates of ancient seawater δ18Ow values. Intra-tooth isotopic variations were observed within individual teeth. Among the selected species, the killer whale （O. orca） has largest intra-tooth δ18Op preference and migratory the lowest δ18Op values and the variation, reflecting its habitat behavior. The results show that oxygen isotope analysis of phosphate in cetacean teeth and dense ear bones provides a useful tool for reconstructing the oxygen isotopic composition of seawater and for examining environmental preferences （including migratory behavior） of both modem and ancient whales.