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This paper establishes an optimization method that can be applied to the flexible operation of the environment control system in an abnormal supply power condition. A proposed conception of lifespan is used to evaluate the depletion time of the non-regenerative substance. The optimization objective function is to maximize the lifespans. The optimization variables are the allocated powers of subsystems. The improved Non-dominated Sorting Genetic Algorithm is adopted to obtain the pareto optimization frontier with the constraints of the cabin environmental parameters and the adjustable operating parameters of the subsystems. Based on the same importance of objective functions, the preferred power allocation of subsystems can be optimized. Then the corresponding running parameters of subsystems can be determined to ensure the maximum lifespans. A long-duration space station with three astronauts is used to show the implementation of the proposed optimization method. Three different CO 2 partial pressure levels are taken into consideration in this study. The optimization results show that the proposed optimization method can obtain the preferred power allocation for the subsystems when the supply power is at a less-than-nominal value. The method can be applied to the autonomous control for the emergency response of the environment control system. [ABSTRACT FROM AUTHOR]

Protoconodonts and conodont-like microfossils are characteristic components in the early Cambrian skeletal faunas. Since the 1970s, these tooth-like phosphatic sclerite fossils have been widely recovered from the Lower Cambrian of China, and altogether 25 genera and 52 species of protoconodonts and conodont-like fossils have been described, although some taxa represent synonyms or invalid taxonomic names, and some assignments are apparently inappropriate. Through a brief review and discussion, the distinction between protoconodonts and conodont-like fossils is denoted here. There are 13 genera previously assigned to protoconodonts in the literature, but present taxonomic revisions show that 5 of them are junior synonyms of other taxa, and 2 represent unknown arthropods. The other 12 genera, of which 5 also are junior synonyms, only reveal a conodont-like morphology with various zoological affinities: most of them are enigmatic, and only Beshtashella and Parafomitchella (= Beshtashella) can be assigned to mollusks. The spatial and temporal distribution of the most genera is briefly discussed. Three intervals of stratigraphic distribution for the protoconodonts not only have significant implications for stratigraphic correlations but also may reflect their evolutionary trend. [ABSTRACT FROM AUTHOR]

The Xiaoyang section, located in Zhenba County of Shaanxi Province, is important both for documenting the biodiversity of the Qiongzhusian Stage (Lower Cambrian) and for analyzing lithofacies-biofacies links in carbonate depositing environments on the Yangtze Platform. The skeletal fossils from the Xihaoping Member, including linguloid valves, cambroclavid and chancelloriid sclerites, genal and occipital spines of polymerid trilobites, and tubular fossils, are described here as the Eoobolus-Cambroclavus fauna, which mainly occurred in peritidal environments. The fossils from the argillaceous limestones of the lower Shuijingtuo Formation, containing lingulate brachiopods eodiscoid trilobites, bivalved arthropods, microdictyoniid sclerites and siliceous sponge spicules, are regarded as the Palaeobolus-Hupeidiscus-Kunmingella fauna, which presumably lived in subtidal or deeper water environments. The faunal diversity in the Xihaoping Member is lower than that in the lower Shuijingtuo Formation. The investigations of the skeletal fossil assemblages from carbonate lithofacies in southern Shaanxi will significantly contribute to a detailed documentation of the biodiversity during the Qiongzhusian interval on the Yangtze Platform and add new knowledge on the Cambrian bioradiation. [ABSTRACT FROM AUTHOR]

Despite a long history of research on the Early Cambrian in China most available data on small skeletal fossils concern fossil associations of the shallow carbonate platform. Information on skeletal fossils from marginal shelf environments of the Yangtze Platform is scanty, which may reflect the rarity of fossils in deeper sedimentary environments but is also due to limitation of carbonate distribution and outcrops, difficulties in fossil extraction, and a general research focus on the Precambrian-Cambrian boundary beds on the carbonate platform. Here we present a documentation of Meishucunian to Qiongzhusian small skeletal fossils from the lower Hetang Formation and the chert unit at its base from the Jiangshan region, Zhejiang Province, representing a relatively deep shelf environment compared to the inner shelf region. The earliest association (Meishucunian) from the chert unit underlying the Hetang Formation is mainly characterized by the occurrence of Protohertzina anabarica, P. unguliformis, Fengzuella zhejiangensis, and Kaiyzngites novilis, which differs somewhat in composition from SSF-associations of typical inner shelf deposits. The enigmatic skeletal fossil Fengzuella zhejiangensis, which exhibits an unusual secretional growth mode previously unrecognized from the Early Cambrian, is described in detail. A younger (Qiongzhusian) fossil association contains numerous arthropod remains, such as disarticulated spines of arthropods (Jiangshanodus- and Kijacus-type), which have previously been considered as conodont-like fossils, and bradoriid valves. [ABSTRACT FROM AUTHOR]

In this paper, guaiacol was used as a model compound of bio-oil and its catalytic conversion was carried out in ethanol. The effect of supports (SBA-15, ZrO2/SBA-15 and SO42-/ZrO2/SBA-15) was studied on Pt-Ni based catalysts whereas the effect of active metals was investigated over C-supported Ru, Pt and Pd catalysts. Among the tested catalysts, Ru/C showed the best performance of total guaiacol conversion with high selectivity towards the desired products, cyclohexanol and 2-methoxycyclohexanol (MCH). The reaction pathways of guaiacol in ethanol were clarified based on the product analysis. With the catalysis of Ru/C, the effects of reaction temperature, initial hydrogen pressure, and other typical compounds from bio-oil were investigated. Temperatures had negligible effect on both the conversion of guaiacol and the yields of desired products in the range of 140-260°C. Guaiacol conversion decreased significantly at initial hydrogen pressures lower than 4.0MPa. The presence of furfural, acetone, and acetic acid decreased the conversion of guaiacol dramatically while the addition of water had a smaller impact. Further work revealed that the mass and energy efficiency of converting guaiacol into MCH are 100% and 97%, respectively. [ABSTRACT FROM AUTHOR]

Volcanic ash beds from shallow- to deep-water facies strata of the Sinian-Early Cambrian (Meishucunian) on the Yangtze Platform consist of bentonites and tuffites which are readily recognized in the field by their physical features and confirmed by geochemical analyses. Geochemistry suggests that the volcanic ash beds in Meishucunian time are rhyolite and rhyodacite while those in the Qiongzhusian and Sinian are andesite and trachyandesite. The ash beds in the time-equivalent strata, even in different areas display rather similar geochemical features, whereas the ash beds in different strata even in the same areas show large chemical difference. The results suggest that these ash beds can be used for intra- and extra-basinal correlations of the Sinian-Early Cambrian interval on the Yangtze Platform. Additionally, these ash beds suggest high potentials for further U-Pb dating strategies. [ABSTRACT FROM AUTHOR]

The Sinian (Terminal Proterozoic) and Early Cambrian shallow- to deep-water sequences of the Yangtze Platform were investigated. Based on integrated lithostratigraphic, biostratigraphic, and other approaches, the shallow- water sequence from the base of the Sinian (base of the Doushantuo Formation) to the top of the Qiongzhusian (top of the Yu'anshan Formation) was subdivided into 12 stratigraphic intervals. These 12 intervals were applied in turn to the subdivision and correlation of the sequences present in various facies of the Yangtze Platform. The high-resolution stratigraphic framework here developed can serve as a time frame for ongoing multidisciplinary analyses of the "Cambrian explosion". [ABSTRACT FROM AUTHOR]

Analysis of the taxonomy and stratigraphic distribution of the Early Cambrian eodiscoid trilobites of the Yangtze Platform indicates that species of TsunyidiscuS and Hupeidiscus can be used for biostratigraphic correlation. T. aclis occurs only in the lower Qiongzhusian, T. armatus occurs in the lower and middle Qiongzhusian, while T. niutitangensis and T. tingi occur mainly in the middle and upper Qiongzhusian, with only T. tingi extending upward into the lower Canglangpuian. H. orientalis first appears in the upper Qiongzhusian reaching peak abundance in the lower Canglangpuian and becoming extinct above the Drepanuroides Zone. Bio-stratigraphic and lithostratigraphic correlations indicate that the limestone in the lower part of the Mingxinsi Formation, the Upper Member of Jiumenchong Formation, and the upper part of the Middle Member of the Huangbailing Formation, can be correlated with each other as Hupediscus an index fossil of the lower Canglangpuian, is abundant in all these units. The lower part of the Niutitang and Jiumenchong formations in eastern Guizhou, which mainly represent Qiongzhusian strata, can be correlated with the Lower Member of the Huangbailing Formation. The basal part of the Niutitang Formation, which may be equivalent to the Upper Meishucunian Shiyantou Formation in eastern Yunnan, is very condensed. Well-preserved sponge faunas and non-mineralized fossils in the lower part of the Niutitang and Hetang formations are not older than Qiongzbusian in age. [ABSTRACT FROM AUTHOR]