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Paleocurrent reconstruction is an important aspect of basin research, playing a key role in the reconstruction of sediment development and understanding the evolution of sedimentary environments. The reconstruction of paleowind direction is an important part of the study of paleoatmospheric circulation, playing a vital role in revealing the characteristics and evolution of paleoclimate. Water flow and wind movement present similar interactions with ground objects and leave direction information. This paper summarises the current common reconstruction theories of paleocurrent and paleowind direction, analyses the advantages and disadvantages of the reconstruction theories, and analyses the characteristics of reconstruction results. Based on the technical structure of paleocurrent and paleowind direction reconstruction, the development of reconstruction theories, processes and results are highlighted. The analysis shows that paleocurrent and paleowind directions can be used for paleoatmospheric circulation research, resource exploration, paleogeographic environment reconstruction and planetary geological research. The current common theories of paleocurrent and paleowind direction reconstruction are outlined. The advantages, disadvantages and scope of application of the reconstruction theory are summarised. Applications and developments in the reconstruction of paleocurrent and paleowind directions are identified. [ABSTRACT FROM AUTHOR]

During the past 50 years, many geological and ore-deposit investigations have led to the discovery of the Fe–P–(Ti)-oxide deposits associated with mafic–ultramafic–carbonatite complexes in the Kuluketage block, northeastern Tarim Craton. In this paper, we discuss the genetic and ore-forming ages, tectonic setting, and the genesis of these deposits (Kawuliuke, Qieganbulake and Duosike). LA-ICP-MS zircon U–Pb dating yielded a weighted mean 206Pb/238U ages of 811 ± 5 Ma, 811 ± 4 Ma, and 840 ± 5 Ma for Kawuliuke ore-bearing pyroxenite, Qieganbulake gabbro and Duosike ore-bearing pyroxenite, respectively. The CL images of the Kawuliuke apatite grains show core–rim structure, suggesting multi-phase crystallisation, whereas the apatite grains from Qieganbulake and Dusike deposits do not show any core–rim texture, suggesting a single-stage crystallisation. LA-ICP-MS apatite 207Pb-corrected U–Pb dating provided weighted mean 206Pb/238U ages of 814 ± 21 Ma and 771 ± 8 Ma for the Kawuliuke ores, and 810 ± 7 Ma and 841 ± 7 Ma for Qieganbulake and Duosike ores, respectively. The core–rim texture in apatite by CL imaging as well as two different ore-forming ages in the core and rim of the apatite indicate two metallogenic events for the Kawuliuke deposit. The first metallogenic period was magmatic in origin, and the second period was hydrothermal in origin. The initial ore-forming age of the Kawuliuke Fe–P–Ti mineralisation was ca 814 Ma and the second one was ca 771 Ma. On the other hand, the ore-forming ages of the Qieganbulake and Duosike deposits were ca 810 Ma and ca 841 Ma, respectively. Qieganbulake and Duosike deposits were of magmatic origin. Combined with previous geochronological data and the research on the tectonic background, we infer that the Kawuliuke, Qieganbulake and Duosike Fe–P–(Ti)-oxide deposits were formed in a subduction-related tectonic setting and were the product of subduction-related magmatism. [ABSTRACT FROM AUTHOR]

We report a new early–middle Eocene cylindrodontid rodent, Gobiocylindrodon ulausuensis, gen. et sp. nov., from the Ula Usu West locality, Erlian Basin, Nei Mongol, China. Gobiocylindrodon ulausuensis is morphologically more primitive than known later cylindrodontids in having lower-crowned molars, less-rounded upper molars in occlusal view, a more oblique hypolophid on p4, a slightly anterolabially extended hypoconid on m1–3, and a narrow posterosinusid posteriorly and a broad mesosinusid anteriorly on the lower cheek teeth. The lower incisor enamel of G. ulausuensis is pauciserial. Our phylogenetic analysis of a data matrix including 14 taxa and 40 morphological characters reveals that G. ulausuensis is a basal cylindrodontid. Gobiocylindrodon ulausuensis casts new light on early cylindrodontid evolution in Asia and provides new evidence for mammalian dispersals between Asia and North America during the early–middle Eocene. Gobiocylindrodon-bearing strata are probably Arshantan in age. [ABSTRACT FROM AUTHOR]

The molecular composition of Carboniferous-Permian coals in the maturity range from 0.66 to 1.63% vitrinite reflectance has been analysed using organic geochemistry to investigate the factors influencing the biomarker compositions of humic coals. The Carboniferous-Permian coal has a variable organofacies and is mainly humic-prone. There is a significant difference in the distribution of saturated and aromatic hydrocarbons in these coals, which can be divided into three types. The Group A coals have biomarker compositions typical of humic coal, characterised by high Pr/Ph ratios, a lower abundance of tricyclic terpanes with a decreasing distribution from C19 tricyclic terpane to C24 tricyclic terpane and a high number of terrigenous-related biomarkers, such as C24 tetracyclic terpane and C29 steranes. The biomarker composition of Group B coals, which were deposited in a suboxic environment, have a higher abundance of rearranged hopanes than observed in Group A coals. In contrast, in Group C coals, the Pr/Ph ratio is less than 1.0, and the sterane and terpane distributions are very different from those in groups A and B. Group C coals generally have abnormally abundant tricyclic terpanes with a normal distribution maximising at the C23 peak; C27 steranes predominates in the m/z 217 mass fragmentograms. The relationships between biomarker compositions, thermal maturity, Pr/Ph ratios and depositional environments, indicate that the biomarker compositions of Carboniferous-Permian coals in Ordos Basin are mainly related to their depositional environment. This leads to the conclusion that the biomarker compositions of groups A and B coals collected from Shanxi and Taiyuan formations in the northern Ordos Basin are mainly related to their marine-terrigenous transitional environment, whereas the biomarker compositions for the Group C coals from Carboniferous strata and Shanxi Formation in the eastern Ordos Basin are associated with marine incursions. [ABSTRACT FROM AUTHOR]

0.94(Bi0.5Na0.5)TiO3-0.06BaTiO3(BNT-BT6) thin films with high piezoelectric property have been prepared by metal organic deposition method. The electric writing and its retention behavior of the thin films are investigated. It has been found that electric writing can be done on BNT-BT6 thin films, and the retention behavior of the thin films on Pt electrodes is polarization dependent. The c−domains exhibits better stability than that of c+domains. With the retention time prolongs, the polarized domain states decays. The retention behavior of BNT-BT6 ferroelectric thin film is attributed to the built-in bias at the BNT-BT6/Pt interface, which triggers the nuclei of c−domains near the domain boundary. [ABSTRACT FROM AUTHOR]

A new method for optimizing ultra-fine pulverization and abating reactive condition of coal liquefaction is investigated. The single fractal and multifractal approaches are applied to analyze the fractal size dimensions of coal samples at various points within 25 h during the ultra-fine pulverizing process. Pyrolysis and infrared spectrum analyses of the samples are carried out and first expressed with the fractal size dimension of smaller particles by a bi-fractal law. It is shown that the fractal size dimension values of smaller particles are ranged from 1.715 to 1.909 and the minimum is 1.715 at 7 h. The breaking of partial chemical bonds and high pyrolysis reactivity have been demonstrated. Finally, the fractal size dimension is proposed as a promising parameter of the combined reactor of both coal ultra-fine pulverization and liquefaction. [ABSTRACT FROM PUBLISHER]

Objective. Decompressive craniectomy (DC) is one of the most ardently debated topics in traumatic brain injury (TBI) treatment. The aim of this study is to compare the differences between DC with and without mass evacuation in patients with TBI. Methods. From January 2005 to December 2009, 164 patients underwent DC at our centre. Seventy-one of the 164 patients underwent DC for diffuse injury (group B). Ninety-three patients underwent DC as part of an operation to treat a mass lesion (group A). Patient characteristics and post-operative outcomes were compared between the two groups. Results. Thirty-six patients died during this study (22.0%). Fifty-nine of these patients (36.0%) remained either vegetative (n = 30) or severely disabled (n = 29). Sixty-nine patients (42%) had a Glasgow Outcome Scale (GOS) score of 4 to 5. Three predictors were significantly related to 60-day mortality: age older than 50 years (odds ratio [OR], 2.36; 95% confidence interval [CI], 1.01-5.52), abnormal pupillary response to light (OR, 3.79; 95% CI, 1.29-11.14), and DC with mass evacuation (OR, 0.31; 95% CI, 0.12-0.79). Mortality differed substantially between patients with (group A) and without (group B) mass evacuation (14.0% versus 32.4%). Only one predictor was significantly related to good outcome: Glasgow Coma Scale (GCS) score at admission: (OR, 2.43; and 95% CI, 1.39-4.24). Conclusions. DC for patients with or without mass lesion has different patient characteristics. DC with mass evacuation has lower mortality than DC without mass evacuation. Outcome prediction following DC should be adjusted according to mass evacuation. [ABSTRACT FROM AUTHOR]

Scanning electron microscope (SEM) observation shows that tumblebug's elytra are a kind of chitin fibre reinforced biocomposite. In the biocomposite, the chitin fibres possess a laminated microstructure and distribute in a kind of particular helicoidal pattern. More careful observation indicates that there is a kind of fibre helicoidally rounding hole in the elytra. Based on the SEM observation, a kind of composite laminate with biomimetic fibre helicoidally rounding hole was fabricated through a special mould and moulding process. The extrusion strength of the biomimetic fibre helicoidally rounding hole was investigated and compared with that of the conventional drilling hole in the composite laminate. It is shown that the extrusion strength of the biomimetic fibre helicoidally rounding hole is markedly larger than that of the conventional drilling hole. [ABSTRACT FROM AUTHOR]

The dispersion of carbon nanotubes (CNTs) in polypropylene (PP) introduces a significant change in the structure and phase evolution during crystallisation at ambient and elevated pressures. The differences between the behaviours of PP and PP containing CNTs are attributed to CNT/polymer interface driven nucleation, which is also responsible for the significant reduction in spherulite size and is associated with the change in equilibrium melting point and percentage crystallinity. This opens the gateway for the use of polymer CNT composites for functional devices, including biomedical and electronic devices. A study of the impact of 1 wt-%CNT additions on the microstructure evolution of PP during pressure induced crystallisation is reported. It is demonstrated that the dispersion of CNTs produces a significant difference in the macromolecular structure and phase evolution during crystallisation at ambient and elevated pressures. The change in equilibrium melting point with pressure is higher for PP containing CNT, which is indicative of the chemical interaction between polymer and CNT. It is found that CNT additions promote the formation of γ-phase at low crystallisation pressure of 0·1-25 MPa, in contrast to the neat PP where α-crystals nucleate at low to moderate pressures (about 0·1-60 MPa) and the γ-phase nucleates at crystallisation pressures exceeding ∼60 MPa. The dependence of equilibrium melting temperature on crystallisation pressure and spherulite size delineates two distinct regimes, characterised predominantly by α- and γ-phases respectively, for both PP and PP-CNT systems. [ABSTRACT FROM AUTHOR]

Zizyphi Spinosi Semen is well known as a kind of herb for the treatment of insomnia and anxiety. However, due to the lack of purified compounds for functional tests, limited data proves pharmacological activities of each jujubasaponin monomer. In this study, we developed a novel method for the preparative separation and purification of jujuboside A, A1, B, and B1, simultaneously, from Zizyphi Spinosi Semen. Macroporous resin and reversed-phase flash chromatography was successfully used and gave a good resolution of each jujubasaponins monomer. Jujuboside A, A1, B, and B1 with a purity of over 98% were yielded. [ABSTRACT FROM AUTHOR]

Due to the requirement of stringent rules for ultra-low sulfur content of diesel fuels, it is necessary to develop alternative methods for desulfurization of fossil fuel derived oil. The desulfurization of aromatic sulfur containing compounds in catalytic cracking diesel oil was carried out using hydrogen peroxide/tri-fluoroacetic acid oxidation system, at the same time, adding power ultrasound to oxidative process, and later the oxidized organic sulfur compounds (sulfones) were extracted by suitable polar solvent. At first, we drew a conclusion of the optimal operating conditions in the laboratory, which is the quantity of the oxidation reagents (oxidant/oil volume ratio) is 1:10; the oxidation temperature is 70°C; reaction time is 60 min; extraction solvent is DMF; S/O is 1:1. In these optimal operating conditions, the power ultrasound can not only make reaction time short, but also increase sulfur removal rate at more than 10%. [ABSTRACT FROM AUTHOR]

Ca-alginate beads were prepared with either external or internal calcium sources. The structures of both beads were investigated with the aid of scanning electron microscopy (SEM) and confocal microscopy. It was shown that the beads with internal calcium source had a looser structure and bigger pore size than those with external calcium source. The attempts to interpret the difference were carried out by determining the Ca content within the beads at various times, which indicated that it was the different gelation mechanisms that caused the difference of structures of both beads. Furthermore, it was also found that the diffusion rate of haemoglobin (Hb) within the beads with an internal calcium source was faster than that of the beads with an external one, which was consistent with the observation of their structures. [ABSTRACT FROM AUTHOR]

The distinctions between the glow and the arc modes of an electric discharge in Ar were investigated using spectroscopy. The study showed that for a glow discharge the 522.1 nm line and for an arc discharge the 427.8 nm line were unique. These lines were used to investigate an electric discharge cooled by forced convection which was shown to be a mixture of a glow and an arc discharge. [ABSTRACT FROM AUTHOR]