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In this work, we successfully assembled an organic–inorganic core–shell hybrid p-n heterojunction ultraviolet photodetector by the electropolymerization deposition of poly(3,4-ethylenedioxyselenophene) (PEDOS) on the surface of zinc oxide nanoarrays (ZnO NRs). The structures of composite were confirmed by FTIR, UV–Vis, XRD and XPS. Mott–Schottky analysis was used to study the p-n heterojunction structure. The photodetection properties of ZnO NRs/PEDOS heterojunction ultraviolet photodetector were systematically investigated current–voltage (I–V) and current–time (I–t) analysis under different bias voltages. The results showed that PEDOS films uniformly grew on ZnO NRs surface and core–shell structure was formed. The p-n heterojunction structure was formed with strong built-in electric field between ZnO NRs and PEDOS. Under the irradiation of UV light, the device showed a good rectification behavior. The responsivity, detection rate and the external quantum efficiency of the ultraviolet photodetector reached to 247.7 A/W, 3.41 × 1012 Jones and 84,000% at 2 V bias, respectively. The rise time (τr) and fall time (τf) of ZnO NRs/PEDOS UV photodetector were obviously shortened compared to ZnO UV photodetector. The results show that the introduction of PEDOS effectively improves the performance of the UV photodetector.

In this study, an electrochemical sensor for dopamine (DA) detection has been developed by a composite of poly(3,4-ethylenedioxyselenophene) (PEDOS) and nitrogen-doped graphene (PEDOS/N-Gr) using an in situ polymerization method. Its structure and properties were then compared with those of the composites of poly(3,4-ethylenedioxythiophene) (PEDOT)/nitrogen-doped graphene (PEDOT/N-Gr), which were prepared by the same methods. FT-IR, Raman, UV-vis, XPS, mapping and SEM investigated the structure and morphology of these composites. These revealed that PEDOS/N-Gr had a higher conjugation degree than PEDOT/N-Gr. The synergetic effect between PEDOS and N-Gr was beneficial for the formation of a homogenous surface coating. The cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods were conducted for electrochemical detection of DA. Compared with PEDOT/N-Gr, the PEDOS/N-Gr displayed an enhanced sensitivity and electrocatalytic performance for DA detection with linear ranges of 0.008–80 μM (PEDOT/N-Gr: 0.04–70 μM) and limits of detection (LOD) of 0.0066 μM (S/N = 3) (PEDOT/N-Gr: 0.018 μM (S/N = 3)).

Checking whether polygons are self-intersecting or not is an important step for GIS projects before they are published to the web. Automatically converting self-intersection polygons into normal ones is practically useful, especially there are numerous polygons need to be processed. Based on the relationships of self-intersection points, this paper presents an algorithm to convert a complex self-intersection polygon to a normal one which has no self-intersection part. Furthermore, using the relationships of the repeat points (original self-intersection points) of the decomposed polygon, the result of the only simple polygon can be split into independent sub-polygons bounded by those points. The algorithm is easy to understand and with high efficiency because we consider only the self-intersection point relationships of the polygon, and we do not pay attention to the edges and their directions. A point structure in which the relationships of the self-intersection points are defined is used in the algorithm.

Through reviewing the generation process and essential characteristics of waterflooding curves, the essence and characteristics of Zhang Jinqing waterflooding curve and Yu Qitai waterflooding curve recommended in Chinese Petroleum Industry Standard “Calculation methods for Recoverable Oil Reserves (SY/T5367—1998)” were discussed, and some technical issues related to the curves were examined in-depth. We found that: (1) All the waterflooding curves are based on empirical formulas derived from oilfield production experience and statistics methods, and can characterize oil displacement features by water quite well. (2) A new waterflooding curve can be derived by combining waterflooding parameters and using different mathematical calculations as long as the parameter combinations and mathematical operation meet a linear relationship, so proposing new waterflooding curves by changing the combination mode has no practical significance anymore. (3) The upwarp of waterflooding curve in the extremely high water cut stage is because the mobility ratio curve has an inflection point with the rapid rise of water cut after reaching a certain value, and the later rapid rise of mobility ratio changes the original two-phase flow dynamics. (4) After entering into water cut stage, all the waterflooding curves with linear relationship can be used to make prediction, even curves with inflection points, as long as they have a straight section above the inflection point. (5) Actual data of waterflooding oilfields has proved that Type A, Zhang Jinqing and Yu Qitai waterflooding curves all can predict accurately oil recoverable reserves in extremely high water cut stage and can be promoted. Key words: extremely high water cut stage, waterflooding characteristic curve, intrinsic essence, reason of upwarp, adaptability

In this paper, composites of poly (3,4-ethylenedioxythiophene) (PEDOT) and sulfonated cellulose (SC) were prepared by oxidative polymerization both in CHCl3 and H2O using different SC contents. The structures of composites (PEDOT/SC) were characterized by Ultraviolet–Visible absorption spectroscopy (UV–Vis), Fourier-transform infrared spectroscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, and scanning electron microscopy. Electrochemical sensing using a PEDOT/SC-modified electrode was performed by the differential pulse voltammetry method. The results indicate that SC acted as a soft template for the formation of fibrous composites. Doping PEDOT with SC affected the conjugation degree and crystallinity of the resulting composites. The results showed that the PEDOT/SC composites obtained in H2O exhibited a higher electrochemical response than those produced in CHCl3. The composites obtained using 5 mg/mL SC in both reaction media had the best electrochemical performance. The electrochemical analysis showed that the limit of detection (LOD) for paracetamol was 0.258 μM and 0.0742 μM, with linear ranges of 0.02–4000 μM and 0.08–1580 μM for composites obtained using 5 mg/mL SC in H2O and CHCl3, respectively.

China is the second largest crude oil consumer in the world. Its demand tendency is of great significance in world crude oil analysis. By applying embodied crude oil method, this paper analyzed the crude oil intensities and flows in China’s economic system from 2011 to 2014. The 56-sector input and output table of China published by World Input-Output Database is used. Firstly, the embodied crude oil intensity of each industry is calculated, which shows the amount of crude oil contained per unit output value of this industry. Secondly, the embodied crude oil intensity and direct crude oil intensity is compared to shed light on the unexpected consumer of crude oil After that, the embodied crude oil flows among industries are calculated. Furthermore, the final utilization of crude oil are analyzed. Lastly, the difference during 2011 to 2014 is shown and the possible reasons are provided. The result shows that Mining and quarrying industry has the highest embodied crude oil intensity, following by manufacture of coke and refined crude oil products. The embodied crude oil intensities of majority industries decreased, which means that in goods with same value from 2011 and 2014, the embodied crude oil in it decreased. The result obtained from embodied crude oil analysis and direct crude oil analysis are quite difference. It implies that embodied crude oil analysis is important in analyzing the future crude oil demand of China.

An unexpected price drop beginning in 2014 has resulted in significant changes in the global crude oil market. This paper investigates the dependency network of the international oil trade and focuses on its changes after the oil price drop. Point-wise mutual information is used to quantify oil trade dependencies, and complex network methods are applied to analyze dependencies at both the country and world levels. The results show that the USA has constructed stable friendships with peripheral countries, and its dependency on traditional oil-producing areas in the Middle East and Africa has decreased significantly. The dependency between Russia and its major partners has undergone a U-curve; it decreased significantly from 2014 to the first half of 2016 and then recovered in late 2016 and 2017. India and its major import sources maintained a stable high dependency during the research period. Community analysis of the dependency network shows structural differences between 2014 and 2017. Large countries such as the USA and Russia changed their community after 2014. The results show that the global oil trade relationships changed considerably after 2014. The new features of dependency and its implications should be considered by policy makers and company managers.

In this paper, the TiO2 nanorod arrays (TiO2 NRAs)/PEDOT-type conducting polymers composites were prepared by a simple electrochemical polymerization method and used as materials for ultraviolet (UV) photodetectors. The poly(3,4-ethylenedioxythiophene) (PEDOT) and poly(3,4-propylenedioxythiophene) (PProDOT) were selected as PEDOT-type conducting polymers. The structural, morphology and properties of photocurrent response of PEDOT/TiO2 NRAs and PProDOT/TiO2 NRAs were systematically studied. The results indicated that the polymer film grown on TiO2 NRAs surface presented three-dimensional porous network structure, and there was a strong interaction between polymer film and TiO2 NRAs. The results of the I–V characteristic curve showed that the composites had good rectification behavior. Due to the p-n heterojunction formed between n-type TiO2 NRAs and p-type polymer, both PEDOT/TiO2 NRAs and PProDOT/TiO2 NRAs had photocurrent response performance under 0 V and 1 V bias. Compared with the PEDOT/TiO2 NRAs, the PProDOT/TiO2 NRAs showed better UV photodetection performance, and the rise and fall time were respectively 26.2 s and 37.78 s at a bias of 1 V, while the rise and fall time were respectively 0.49 s and 8.79 s at a bias of 0 V. This research has certain potential and application value in the field of UV photodetectors.

The fact that uranium, coal, oil, and other ores occur in the same sedimentary basin has been extensively recognized. By comparing the spatial and temporal relationships among uranium, coal, and hydrocarbons, we found that the ore-bearing uranium and coal layers within the same basin are commonly interbedded or adjacent to each other. In general, however, uranium deposits are spatially distant from oilfields. We analyzed the genetic relationship among oil, coal, and uranium by compiling numerous geological surveys, test analyses, and previous studies of the Ili, Songliao, and other basins in North China. It is considered that the mild and humid paleoclimate should be an important factor affecting the formation of coal reservoir, mudstone as the upper and lower aquifuges, and the host rocks with rich organic matters. Thus, these coal-mining areas occurring at the edges of basins deserve to be studied in detail for uranium exploration. In addition, the metallogenic epochs are roughly similar to the epochs of hydrocarbon migration and tectonic events. These existing data of oil exploration can be used to unravel the regional and local tectonic evolutions of the basin related to uranium mineralization. Finally, a rough relationship between uranium mineralization and hydrocarbons was presented. Note that hydrocarbon is not just beneficial for the formation of uranium deposits but may also inhibit the transportation and mineralization of uranium-bearing materials. Regions with shallow hydrocarbon fields or large quantities of hydrocarbon dissipation are not the ideal exploration locations for uranium.

Additional file 1 Supplementary figures. Fig S1: Distribution of replicate numbers employed in surveyed GEO studies. Fig S2: Design of Decode-seq. Fig S3: Downsampling of sequencing depth. Fig S4: Performance evaluation of Decode-seq at 3-fold change level using human/mouse RNA mixes. Fig S5: Performance evaluation of Decode-seq with 10 ng and 1 ng RNA at 5-fold change level. Fig S6: Sequencing quality scores and nucleotide distribution of BRB-seq and Decode-seq. Fig S7: Spearman’s correlations of human gene UMI counts between technical replicates of Decode-seq and BRB-seq. Fig S8: DE performance of BRB-seq and Decode-seq when using different edgeR filtering parameters. Fig S9: Genetic knockout of ENSORLG00000007290 by four-guide Cas9 RNP.

Additional file 5 Review history.

Additional file 3 Supplementary methods.

The revised details of SY/T5358—2010 of National Energy Administration Standard from five aspects are put forward, it is aimed at existing flaws of the standard, including measurement procedures, evaluation method and discrimination criteria of the rock stress sensitivity. Terzaghi's effective stress was derived according to stress equation of Bane and Maximov, which indicates Terzaghi formula, is not only suitable for soil mechanics, but also for rock mechanics. An exponential model of Terzaghi effective stress and rock permeability was built from former researcher's formula of permeability modulus. The exponential model was used to fit experimental data, with a good accuracy under two different experiment conditions, constant confining pressure (constant-external pressure) and changing-pore-fluid pressure (changing-internal pressure), and constant-pore-fluid pressure (constant-internal pressure) and changing-confining pressure (changing-external pressure). Since constant-external pressure and changing-internal pressure accords with the actual oilfield development, it is recommended to be used in the laboratory operation. It is concluded through the study that the stress sensitivity of reservoir rock can be evaluated with stress sensitivity coefficient α of the exponential model, the stress sensitivity coefficient, 0.005 MPa−1

To meet the needs of oilfield strategic planning and reservoir management, a new method for development evaluation of waterflooding reservoir was established. Five key indexes are determined by analyzing the existing index system, screening from the main development indexes by methods such as logical analysis and correlation analysis, and studying the matching rules among the development indexes and reservoir geological characteristics, development characteristics, and development stages. Moreover, methods were proposed for determining the reasonable boundaries, the membership functions and the weights of evaluation indexes. Finally, a comprehensive evaluation method of multi-indexes was established. This paper first proposes the stage definition of evaluation indexes, the method for determining the respective evaluation criteria, and evaluating the development effects according to the different development stage, which make the results more reasonable.

The biocompatibility of surface-modified biphasic calcium phosphate (mBCP)/poly-L-Lactide (PLLA) biocomposite was investigated through a series of experiments in vitro and in vivo . Acute toxicity and short term systemic toxicity experiments revealed no toxicity of the materials. Hemolysis assay indicated the good blood compatibility of the composite. In cytotoxicity assay, L929 mouse fibroblasts could well differentiate and proliferate. Animal experiments in vivo were performed by implanting the materials into rabbits muscle for 8 weeks. The decreasing of inflammatory cells, the building of fibrous tissue layer as well as the growing of blood cells into materials indicated the nontoxicity of the composite. Based on the experiment results, surface-modified BCP/PLLA biocomposite is proven to have superior biocompatibility, which would be a promising bone repairing material.

The chromospherically-active binary, V711 Tau, had been observed by using the American Very Large Array (VLA) at five bands from 1.4 to 15 GHz. During the observation, the source was undergoing an intense flare, its radio luminosity up to 1.8 x 10(18) erg s-1 Hz-1. The degree of circular polarization in the phase of the most intense flare was very small. With the decaying of the flare the flux density decreased, spectral index became smaller, spectra steeper and reversal frequency lower; the degree of circular polarization increased and its direction was dependent on frequency. These observational facts support the conclusion that the emission during intense flare is synchrotron (or synchro-cyclotron) mechanism. The magnetic intensity is about 10 G near tau = 1, the average electron energy, 4 MeV, the electron density with larger than 10 keV, 3 x 10(4)-9 X 10(4) cm-3 and the electronic energy spectrum index in power-law distribution 1.3.