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In this work, the support vector machine (SVM) method is adopted to separate BL Lacertae objects (BL Lacs) and flat spectrum radio quasars (FSRQs) in the plots of the photon spectrum index against the photon flux, α ph ∼ log F , those of the photon spectrum index against the variability index, α ph ∼ log V I and those of the variability index against the photon flux, log V I ∼ log F . Then, we used the dividing lines to distinguish BL Lacs from FSRQs in the blazar candidates of uncertain types from the Fermi/LAT catalogue. Our main conclusions are: 1. We separate BL Lacs and FSRQs by α ph = − 0.123 log F + 1.170 in the α ph ∼ log F plot, α ph = − 0.161 log V I + 2.594 in the α ph ∼ log V I plot and log V I = 0.792 log F + 9.203 in the log V I ∼ log F plot. 2. We obtain 932 BL Lac candidates and possible BL Lac candidates, and 585 FSRQ candidates and possible FSRQ candidates. 3. Discussion is given regarding comparisons with the literature. [ABSTRACT FROM AUTHOR]

Effective photosensitizers (PSs) are at the heart of the key role of photo-driven antibacterial therapy. However, relative high temperature required for bactericidal activity, stimulating at multiple wavelengths, and multi-step synthesis of the photothermal and photodynamic agents challenge their applications in antibacterial treatment. In this study, silver nanoparticles (AgNPs) functionalized by kaempferol (Kae) are implanted into Prussian blue (PB) to construct photo-responsive nanocubes (AgPB) by a simple synthetic process. The as-synthesized AgPB nanocomposites were found to have an average size of ∼140 nm, and the particle size range of the loaded-AgNPs was 5–15 nm. The structure of AgPB was characterized, and the photothermal and photodynamic evaluation of antibacterial activity of AgPB was investigated under single 808 nm near-infrared (NIR) light. By adjusting the doping ratio of AgNPs, the band gap can be tuned from 2.78 to 2.56 eV to further enhance the photothermal conversion of AgPB and its ability to generate reactive oxygen species (ROS). When compared with AgPB without NIR illumination, in vitro antibacterial studies by using Escherichia coli and Staphylococcus aureus showed that AgPB under 808 nm NIR light could rapidly heat up to 50 °C, enhance the formation of ROS, and promote the ion release amount of Fe2+, Fe3+, and Ag+ to increase oxidative stress, leading to inhibition of bacterial proliferation significantly. Both E. coli and S. aureus were completely killed within 10 min. Moreover, the biofilm formation was remarkably inhibited, and the eradication ratio against E. coli and S. aureus biofilms was 69.73 and 60.01%, respectively. In addition, the hemolytic activity test proved that AgPB had good biocompatibility. The results showed that AgPB with triple bactericidal modalities could expand the application of PSs and serve as a promising nanocomposite for antibacterial therapy. [ABSTRACT FROM AUTHOR]

Orogenic growth, characterized by formation and forward propagation of fold‐thrust belts and foreland basins, is predicted by wedge models of thrust systems. The growth of the Nanpanjiang fold‐thrust belt and foreland basin system of the Indosinian orogenic belt in the southwestern South China remains poorly understood. The development of the Indosinian foreland system remains underappreciated due to few constraints on structural styles, kinematics and ages. Surface cross sections, seismic profiles and detrital zircon data are presented to address the structural styles and evolution of the Indosinian foreland system. The results reveal that the fold‐thrust belt is characterized by fault‐related folds with deeper duplexes and shallower imbricates, which yield a NNE‐SSW regional shortening magnitude of ∼36%. Our new constraints indicate that the Nanpanjiang region experienced multi‐staged thrusting during the Indosinian orogeny (D1). The D11 affected the southernmost southern fold‐thrust belt, producing thick‐skinned thrusts involving Neoproterozoic basement and initiating the Nanpanjiang foreland basin. During the D12, NNE‐verging thick‐skinned thrusting continued and was followed by thin‐skinned thrusting in the northern fold‐thrust belt. Locally preserved foreland basin deposits at the northernmost Nanpanjiang Basin define D13. The progressive D14 co‐axially deformed the residual basin into a wide and gentle syncline. Thus, the progressive D11 to D14 deformation sequence of NNE‐verging in‐sequence thrusting and foreland basin migration describe the kinematic and dynamic relationship between fold‐thrust belt and foreland basin during the Indosinian tectonic event. Indosinian D1 structures were subsequently refolded by the Yanshanian tectonic event (D2), forming N‐ to NE‐striking cleavage and arcuation of D1 fold axes. Key Points: The Nanpanjiang fold‐thrust belt and its associated foreland basin migrated NNE‐ward during the Middle Triassic to Early JurassicIndosinian deformation produced an orogenic wedge with a thick‐skinned hinterland belt, a thin‐skinned foreland belt and shortening of 36%In‐sequence thrusting and foreland‐propagation (237–186 Ma) led to incorporation of the Nanpanjiang foreland basin into the fold‐thrust belt [ABSTRACT FROM AUTHOR]

The Cenozoic evolution of SE Asia is marked by thousands of kilometres extension on the continental margin, including normal faults, half‐grabens, and volcanic rocks, but dating of brittle faults in the shallow crust is difficult because of a lack of synkinematic minerals. The Cenozoic extension in the Youjiang fold‐thrust belt in southwest China is marked by brittle normal faults and half‐grabens filled with Paleogene sediments in the region. Here, we identified a strongly weathered mafic sill that was truncated by normal faults in the fold‐thrust belt and present the age and chemistry of zircons from a weathered sill. The zircons from the sill yielded a mean age of ~35 Ma. Integrating cross‐cutting relationship and zircon U–Pb dating suggest that the Cenozoic extension was initiated later than ~35 Ma in Youjiang fold‐thrust belt in southwest China. Combined with structural analysis and previous fission track data in the region, we suggest that the normal faults in this study provide evidence of surface fault activity of Cenozoic extension in SE Asia caused by retreat of a trench system. Furthermore, this study provides a case study to discuss how to decipher brittle normal faulting using zircon geochronology and structural and textural analysis from the mesoscale to the microscale. [ABSTRACT FROM AUTHOR]

Remote sensing techniques are widely used during petroleum exploration. However, limitations in spectral and spatial resolution mean that these techniques are used mainly to detect hydrocarbons either indirectly or under laboratory conditions. To investigate the spectral signatures of natural hydrocarbon-bearing features, we took spectral measurements from oil seeps and associated hydrocarbon-bearing materials in Karamay city, northwest China. The hydrocarbon content of 16 hydrocarbon-bearing samples was also determined to study the relationship between hydrocarbon content and spectral absorption. The results reveal a positive correlation between spectral absorption intensities at 1725 nm and hydrocarbon contents of >1 wt%. Thus, surface hydrocarbon content can be direct detection above a detection limit of around 1 wt% using this method. This result is not only instructive for petroleum exploration, but also important for environmental protection. [ABSTRACT FROM AUTHOR]

Karamay city in Xinjiang Uygur Autonomous Region, northwest China, has a developed petroleum industry and has many geosites of high educational and scientific interest. For example, an ophiolitic mélange displays a complete sequence of ancient oceanic crust and allows analysis of the tectonic evolution of the Paleo-Asian Ocean; Black Oil Hill, asphaltum deposit, and outcrops of the source rock display a complete system of fault-controlled oil seepage from depth to the surface; and World Ghost Town is one of the three most striking yardang landforms in China, and its Junggar pterosaur fossils provide clues to the evolutionary ecology and paleogeography of global pterosaurs. Through multitemporal remote-sensing technology and fieldwork, this study found that Karamay's geosites have been severely damaged or are threatened by human activities. Geoconservation action is urgently needed. [ABSTRACT FROM AUTHOR]

Two phases of diabase-sill-forming magmatism are recorded within the Badu anticline where magmas were emplaced into upper Palaeozoic carbonates and clastic rocks of the Youjiang fold-and-thrust belt in the SW South China Block, China. Zircons from these diabase units yield weighted mean U–Pb ages of 249.2±2.0 Ma and 187.1±3.3 Ma, and magmatic oxygen fugacity values from ‒20 to ‒6 (average of ‒12, equating to FMQ +5) and ‒20 to ‒10 (average of ‒15, equating to FMQ +2), respectively. These data indicate that the sills were emplaced during Early Triassic and Early Jurassic times. The discovery of c. 250 Ma mafic magmatism in this area was probably related to post-flood-basalt extension associated with the Emeishan mantle plume or rollback of the subducting Palaeo-Tethys slab. The c. 190 Ma diabase sills indicate that the southwestern South China Block records Early Jurassic mafic magmatism and lithospheric extension that was likely associated with a transition from post-collisional to within-plate tectonic regimes. The emplacement of diabase intrusions at depth may have driven hydrothermal systems, enabling the mobilization of elements from sedimentary rocks and causing the formation of a giant epigenetic metallogenic domain. The results indicate that high-oxygen-fugacity materials within basement rocks caused crustal contamination of the magmas, contributing to the wide range of oxygen fugacity conditions recorded by the Au-bearing Badu diabase. In addition, data from inherited xenocrystic zircons within the Badu diabase and detrital zircons from basement rocks suggest that the Neoproterozoic Jiangshao suture extends to the south of the Badu anticline. [ABSTRACT FROM AUTHOR]

Bottom-like flowing pressure (BHFP) prediction for multi-stage fractured horizontal shale gas with constant rate production is a key problem of stable production period estimation. Based on the transient linear flow theory of multi-stage fractured horizontal shale gas, the rate-time superposition function (Qg・t0.5)sup is proposed, a type curve identification charts of pseudopressure difference [m(pi)-m(pwf)]-rate-time superposition function (Qg・t0.5)sup is established, a parameter group of m which could reflect reservoir properties and fractured effect is determined, an BHFP prediction analytical solution function for constant rate production shale gas well is constructed. This method is applied in constant rate production and variable rate production shale gas wells, the results show that there is an excellent coincidence rate between predicted BHFP and monitored BHFP, which is above 95%, and the forecasting precision of stable production period is above 90%. This BHFP prediction method has an important guiding significance for stable production period prediction, rational proration of multi-stage fractured horizontal shale gas well with constant rate production. [ABSTRACT FROM AUTHOR]

Gas content is a key parameter for shale reserves estimation，production prediction and gas rate decline analysis. The storage mechanisms in shale is contained free and adsorption，and there are many different gas content testing methods such as gravimetric isotherm method，volume isotherm method and traditional testing method in field. In this study，a new shale gas content lab testing method is proposed based on measuring the gas volume changes during shale gas desorption. In this new method，cylindrical shale cores are used for simulating the influences of temperature，pressure，moisture content，real pore structure on total gas content，negative adsorption anomalies are eliminated by using this method. The experimental results revealed that adsorption gas content increased with pressure and the volume of adsorption gas content is at equilibrium and does not increase while the pressure is up to 12MPa. There is a positive relationship between adsorption gas content and TOC，and a negative relationship between adsorption gas content and temperature and moisture content. Adsorption of methane is higher than the nitrogen adsorption in shale. At a temperature of 20℃，under pressure of 30MPa，the adsorption gas content of Longmaxi shale in Jiaoshiba is 1.8-3.1m3/t and total gas content is 5.1-6.5m3/t，and about 40% of the total volume is adsorbed gas. [ABSTRACT FROM AUTHOR]