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Resolving how Earth surface redox conditions evolved through the Proterozoic Eon is fundamental to understanding how biogeochemical cycles have changed through time. The redox sensitivity of cerium relative to other rare earth elements and its uptake in carbonate minerals make the Ce anomaly (Ce/Ce*) a particularly useful proxy for capturing redox conditions in the local marine environment. Here, we report Ce/Ce* data in marine carbonate rocks through 3.5 billion years of Earth's history, focusing in particular on the mid-Proterozoic Eon (i.e., 1.8 - 0.8 Ga). To better understand the role of atmospheric oxygenation, we use Ce/Ce* data to estimate the partial pressure of atmospheric oxygen (pO2) through this time. Our thermodynamics-based modeling supports a major rise in atmospheric oxygen level in the aftermath of the Great Oxidation Event (~ 2.4 Ga), followed by invariant pO2 of about 1% of present atmospheric level through most of the Proterozoic Eon (2.4 to 0.65 Ga).

In video surveillance and intelligent traffic,bad weather such as foggy,rainy and snowy can seriously affect the visibility of video images.Therefore,it is very important to quickly identify the current weather conditions and make adaptive clearness processing of surveillance videos.Aiming at the problems of poor effect of traditional weather recognition methods and lack of weather image data sets,a multi-class weather image blocks data set is constructed,and a weather recognition algorithm based on image blocks and feature fusion is proposed.The algorithm uses traditional methods to extract four features,namely average gradient,contrast,saturation and dark channel,which are taken as the shallow features of weather images.The algorithm uses transfer learning to fine -tune the VGG16 pre-training model,and extracts the full-connection layer features of the fine-tuning model,which are taken as the deep features of the weather image.The shallow and deep features of weather images are fused and used as the final features to train the Softmax classifier.The classifier can realize the recognition of foggy,rainy,snowy and sunny wea-ther images. Experimental results show that the recognition accuracy of the proposed algorithm can reach 99.26%,and the algorithm can be used as a weather recognition module in the adaptive video image sharpening system.

Strontium isotope ratios (87Sr/86Sr) are gaining considerable interest as a geolocation tool and are now widely applied in archaeology, ecology, and forensic research. However, their application for provenance requires the development of baseline models predicting surficial 87Sr/86Sr variations (isoscapes). A variety of empirically-based and process-based models have been proposed to build terrestrial 87Sr/86Sr isoscapes but, in their current forms, those models are not mature enough to be integrated with continuous-probability surface models used in geographic assignment. In this study, we aim to overcome those limitations and to predict 87Sr/86Sr variations across Western Europe by combining process-based models and a series of remote-sensing geospatial products into a regression framework. We find that random forest regression significantly outperforms other commonly used regression and interpolation methods, and efficiently predicts the multi-scale patterning of 87Sr/86Sr variations by accounting for geological, geomorphological and atmospheric controls. Random forest regression also provides an easily interpretable and flexible framework to integrate different types of environmental auxiliary variables required to model the multi-scale patterning of 87Sr/86Sr variability. The method is transferable to different scales and resolutions and can be applied to the large collection of geospatial data available at local and global levels. The isoscape generated in this study provides the most accurate 87Sr/86Sr predictions in bioavailable strontium for Western Europe (R2 = 0.58 and RMSE = 0.0023) to date, as well as a conservative estimate of spatial uncertainty by applying quantile regression forest. We anticipate that the method presented in this study combined with the growing numbers of bioavailable 87Sr/86Sr data and satellite geospatial products will extend the applicability of the 87Sr/86Sr geo-profiling tool in provenance applications.

The basic principles and methods of infrared radiation and infrared stealth technology were discussed in this paper. It was found that flexible regulation of multi-band spectrum was the key to realize infrared stealth compatible with radar stealth, laser stealth and visible light stealth. The research status of traditional infrared stealth materials were summarized and the bottleneck of their development was clarified. Furthermore, the design idea, research basis and development advantages of infrared stealth metamaterials with spectral tailoring function were proposed. We reviewed the research status and development trend of the infrared stealth compatible with radar stealth, infrared stealth with infrared radiation window and infrared stealth compatible with laser and visible light.

We evaluate the factors influencing the abundance, [Li], and isotopic composition of riverine Li delivered to the oceans through analyses and modeling of [Li] and δ7Li in streams and groundwaters draining a single continental lithology, the Columbia River Basalts (CRBs). The streams were sampled in different climate zones that lie east (dry), and west (wet) of the Cascades Mountains, and during two different seasons (summer and late winter) in order to evaluate climatic and seasonal influences on Li isotopes in rivers. Dissolved Li (δLidis7=+9.3 to +30.4) is systematically heavier than that of fresh or weathered CRBs (-4.7 to +6.0, Liu et al., 2013), suspended loads (-5.9 to -0.3), and shallow groundwaters (+6.7 to +9.4), consistent with previous studies showing that Li isotope fractionation is affected by equilibration between stream water and secondary minerals. However, the lack of correlation between δ7Lidis and climate zone, the uniform secondary minerals and bedrock, coupled with the highly variable (>20‰) δLidis7 indicate that other factors exert a strong control on δ7Lidis. In particular, the heavier Li in streams compared to the shallow groundwaters that feed them indicates that continued isotopic fractionation between stream water and suspended and/or bed loads has a major influence on riverine δ7Li. Seasonal δ7Li variation is observed only for streams west of the Cascades, where the difference in precipitation rate between the dry and wet seasons is greatest. Reactive transport model simulations reveal that riverine δ7Li is strongly controlled by subsurface residence times and the Li isotope fractionation occurring within rivers. The latter explains why there is no positive correlation between δ7Li and traditional weathering proxies such as Si or normalized Si in rivers, as riverine Li isotope fractionation drives δ7Li to higher values during transport, whereas the concentrations of major cations and anions are diluted. The varying residence time for groundwaters feeding the western streams in summer (long residence times, higher δ7Li, greater weathering) and winter (short residence times, lower δ7Li, less weathering) explains the observed seasonal variations. A global, negative correlation between δ7Li and Li/Na for streams and rivers draining basaltic catchments reflects the overall transport time, hence the amount of silicate weathering. Based on our results, the increase of δ7Li in seawater during the Cenozoic is unlikely related to changing climate, but may reflect mountain building giving rise to increased silicate weathering.

Mineralogical, chemical, and Li and Nd isotopic compositions of two drill cores (8-9m deep) through bauxites developed on the Miocene Columbia River Basalts document the changes associated with basalt weathering, provide insights into the processes involved, and allow us to examine the overall influence of chemical weathering on juvenile (basaltic) crust. Gibbsite, hematite, ±kaolinite, halloysite, goethite, and maghemite are the weathering products in the bauxites. Quartz is observed near the tops of the cores and its abundance decreases progressively with depth; no quartz is observed below five meters depth in either core. Most major and trace elements, including "mobile" and some "immobile" elements are severely depleted in the bauxites. Niobium is less mobile relative to the rare earth elements, thus chemical weathering attenuates the negative Nb anomaly in the continental crust. Li and Nd are strongly depleted relative to fresh basalt, and both increase systematically towards the surface in the quartz-bearing samples while δ7Li and εNd values decrease systematically towards the surface in these same samples. Both Li and Nd were likely lost from the bauxites through leaching. The systematic enrichment of Li, Nd, and quartz, as well as the less radiogenic Nd isotopic composition at the tops of both profiles reflects 20-60wt.% addition of an eolian component to the soils. The eolian dust is unlikely to have experienced significant post-depositional weathering due to the relatively high Li contents near the tops of the profiles, and, therefore, the low δ7Li and εNd values suggest that the dust came from an old, weathered region of the continent. Our results demonstrate that lithium isotopes are sensitive tracers of chemical weathering, particularly in extreme weathering settings, and support the hypothesis that chemical weathering influences the mass and composition of the continental crust. © 2013 Elsevier Ltd.

The effect of pedestrian and bicycle infrastructure is used to analyze the capacity for right-turn lane at signalized intersection. Each cycle at the signalized intersection was divided into several periods. The effect of pedestrian and bicycle at each period was analyzed. The number of right-turn cars going through signalized intersection was calculated by using probability theory and mathematical statistics. The capacity under the effect of pedestrian and bicycle for right-turn lane at signalized Intersection was deduced. The calculated results were deduced by using the survey data of two signalized intersections at Jinan city. The mean difference values are 8% and 10.1%, compared with VISSIM simulation results. The comparisons show that this model can fully describe the effect of pedestrian and bicycle to signalized intersection.

The X-ray Fluorescence Spectrometry (XRF) method was adapted for the determination of 10 major elements, such as silicon, aluminum, calcium and magnesium, in different types of rocks. The calibration curves were determined from 28 different types of rock standards which were fused into glass beads. The matrix effect was calibrated by using empirical factors. This method was used for determining the 10 major elements of samples from GeoPT proficiency testing. The 23 types of rock samples were analyzed over 15 years and the results indicate that this method is most effective in determining SiO2, Al2O3, K2O and CaO with the obtained|Z| < 2 for all samples. This method is also suitable for determining MgO, MnO, TiO2 and Na2O although each element has only one suspect result in different samples with the obtained|Z|>2, which was caused by the matrix difference between samples and standard samples in measuring the lower content elements. When the content of TFe2O3 is higher than 1.00% and P2O5 between 0.08% and 0.80%, the results can match expectations (the obtained|Z| < 2). To sum up, the developed XRF method has long term stability and is effective, which can match the expectation of applied geochemistry laboratories for determination of 10 major elements in different types of rock samples.

In this paper, we present the methods of parametrically reconstructing the position of a 3D scattering center model of the targets from SAR images for a target recognition application. First, a framework for reconstructing the 3D position of the targets from the SAR images is proposed. Then, a method that uses the parameters obtained from the scattering center of the targets from the SAR images is used for reconstructing the 3D scattering center model. Finally, the proposed methods are confirmed using the simulated data.

The accuracy of the certified values of the national reference materials plays an important role in instrument calibration, and therefore quality control for analysis data. In order to test the accuracy of the certified values of the Chinese National Standard Reference Materials, 36 trace elements were determined for 18 National Standard Reference Materials of rock (from GBW 07103 to GBW 07125), 19 National Standard Reference Materials of sediment (from GBW 07301 to GBW 07318) and 19 National Standard Reference Materials of soil (from GBW 07401 to GBW 07430) by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). These National Standard Reference Materials were digested by using the pressurized acid digestion technique. The relative standard deviation (RSD) of most trace elements in these materials were typically better than 10%, except for Ni, Cr, Pb, Co, Cu, Sc, Yb and Lu in several reference materials. Most of the results were consistent with the certified values in the literature, and with a relative error of less than 10%. Results given here indicate that a few certified values of some reference materials should be revised. In addition, content values of some trace elements in the National Standard Reference Materials of sediment or National Standard Reference Materials of soil, such as Ni for GBW 07306, Be, Hf and Ta for GBW 07313, Li and Be for GBW 07314, Hf and Ta for GBW 07409, GBW 07410 and GBW 07411, Gd and Ta for GBW 07426 are provided here.