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In order to further improve the yield of aromatic monomers from renewable resources, the selective cleavage of C–C bonds in lignin get more and more attention. In this work, Cs 3 Bi 2 Br 9 (CBB) and covalent triazine frameworks (CTFs) complexes were firstly prepared by facile melting salt method. Due to CBB quantum dots embedded in CTF frame structure, the conversion rate of the composite photocatalyst for 2-phenoxy-1-phenylethanol (pp-ol) reached 100% under visible-light irradiation in 6 h. In-depth investigations verified that the electronic structure of the photocatalyst could be adjusted by changing calcination temperature. The electronic structure of the photocatalyst affected the type and the tendency of free radical, and then affected the selectivity of C-C bond cleavage. This work provides a simple method to prepare photocatalytic and used for aromatics production from renewable biomass feedstocks. • Cs 3 Bi 2 Br 9 (CBB) and covalent triazine frameworks (CTFs) complexes were firstly prepared by facile melting salt method. • The electronic structure can be adjusted by changing the calcination temperature. • h+ and •O 2 – play an important role in cracking C α -C β bond. [ABSTRACT FROM AUTHOR]

An adaptive robust controller with non-local memory hysteresis force compensation is investigated for the precision tracking control of pneumatic artificial muscle (PAM). The proposed controller presents a two-layer cascade structure, and each layer has an adaptive law part and a robust control law part. A modified operator based Prandtl–Ishlinskii (PI) model is employed in the development of the robust control algorithm with the hysteresis feedback linearization compensation. Moreover, in the robust control law part, the problem of unbounded uncertain nonlinearities introduced by the hysteresis force term is addressed by applying an on-line monitoring method. In the adaptive law part, model parameters including weights of the modified operator are updated online by the recursive least squares estimation (RLSE) method, and then the effect of the hysteresis non-local memory characteristic is further attenuated. The tracking error is guaranteed to converge to a small residual set. Comparative experimental results demonstrate the significance of the non-local memory hysteresis force compensation, then, a desired precision can be guaranteed. [ABSTRACT FROM AUTHOR]

This paper addresses the problems of robust stability analysis and L 1 -gain controller synthesis for uncertain impulsive positive systems. First, by employing the idea of impulse interval partitioning, an impulse-time-dependent discretized copositive Lyapunov function is proposed to analyze the robust stability and L 1 -gain performance of the considered system without control inputs, and several stability conditions and L 1 -gain criteria are respectively derived. Subsequently, a sufficient condition is formulated for the existence of state-feedback controllers with which not only the positivity and robust uniform asymptotic stability of the resulting closed-loop system are guaranteed, but also a prescribed L 1 -gain performance is satisfied simultaneously. Furthermore, to make the controller synthesis problem numerically tractable, we propose an iterative convex optimization algorithm to compute the desired controller parameters. Finally, three numerical examples and two realistic examples are presented to show the effectiveness and applicability of the proposed methodology. • Several sufficient conditions about the RUAS and L 1 -gain performance are developed. • A sufficient condition for the existence of the L 1 -gain controller is derived. • An iterative convex algorithm is developed to compute the controller parameters. [ABSTRACT FROM AUTHOR]

Increasing production and application of nanomaterials lead to their environmental release possible. The nanomaterials with different properties may transport together in porous media, and consequently affect their environmental fates. In this study, column experiments were conducted to investigate the co-transport of two typical nanomaterials, graphene oxide (GO) and nano-titanium dioxide (nTiO 2), in saturated quartz sand in NaCl and CaCl 2 electrolyte solutions under both favorable and unfavorable conditions. The breakthrough curves as well as the retained profiles of single and binary nanoparticles were examined. The results indicated that nTiO 2 significantly enhanced the GO retention under all examined conditions, especially at lower pH, higher ionic strength and the presence of divalent cation Ca2+. This might be attributed to the formation of less negatively charged and larger-sized GO-nTiO 2 agglomerates as well as the increased retention sites on sand surface by preferentially deposited nTiO 2. However, GO merely slightly enhanced the transport of nTiO 2 in NaCl solutions, whereas had negligible effect on nTiO 2 transport and retention in CaCl 2 solutions. The highly hydrophilic and mobile GO served as a carrier and facilitated the transport of nTiO 2 in NaCl solutions. In CaCl 2 solutions, the strong attachment affinity between positively charged nTiO 2 and negatively charged quartz sand (at pH 4.5), and dramatical accumulation of large nTiO 2 agglomerates near the column inlets (at pH 6.5) led to significant deposition of nTiO 2 on quartz sand. The co-presence of GO failed to counteract the retention of nTiO 2 particles on sand. Image 1 • nTiO 2 inhibited GO transport, especially at lower pH, higher ionic strength and the presence of Ca2+. • The formation of GO-nTiO 2 agglomerates and increased retention sites by deposited nTiO 2 decreased GO transport. • Highly hydrophilic and mobile GO slightly enhanced the transport of nTiO 2 in NaCl solutions. • GO had negligible effects on the transport of nTiO 2 in CaCl 2 solutions. Capsule : nTiO 2 significantly inhibits the transport of GO, whereas GO has slight or negligible enhancement effects on the transport of nTiO 2 in saturated quartz sand. [ABSTRACT FROM AUTHOR]

The fast-growing production and application of carbon nanotube (CNT) materials in a variety of industrial products inevitably lead to their release to wastewater and surface water. CNT would experience oxidization in wastewater treatment plant due to the presence of large amount of disinfectants, such as H 2 O 2 and O 3 , which in turn affects the environmental fates and risks of CNT. In this study, oxidized CNT materials (O-CNTs) were prepared by treating CNT with H 2 O 2 /UV and O 3 (denoting as H 2 O 2 -CNT and O 3 -CNT, respectively). A variety of characterizations indicated that oxygen containing groups were generated on CNT surface upon the oxidation, and the O/C ratio increased in the order of pristine CNT < H 2 O 2 -CNT < O 3 -CNT. In the presence of Na+, K+ and Mg2+, the O-CNTs displayed better colloidal stability than the pristine CNT, and the stability increased with the oxidation degree (indicated by O/C ratio). This could be explained by the more negative surface charge and stronger hydrophilicity of the O-CNTs. Unexpectedly, in the presence of Ca2+, the most oxidized O 3 -CNT exhibited the poorest colloidal stability. The abundant carboxyl groups in O 3 -CNT provided effective binding sites for cation bridging effect through Ca2+ and led to stronger aggregation. Increasing pH was more favorable to disperse CNTs (both O-CNT and pristine CNT) in the presence of Na+, but much less effective in inhibiting the aggregation of O 3 -CNT in presence of Ca2+. This could be explained by the stronger cation bridging effect due to enhanced deprotonation the –COOH groups at higher pH conditions. The calculated Hamaker constants of the CNTs decreased with the oxidation degree, implying that there was lower van der Waals force between the O-CNTs. The Derjaguin–Landau–Verwey–Overbeek (DLVO) calculation confirmed that O-CNTs had to overcome higher energy barrier and thus showed better colloidal stability than the pristine CNT in the presence of Na+. Image 1 • Oxidation treatments introduced oxygen containing functional groups on CNTs. • The O/C ratio and oxidation degree increased in the order of pristine CNT < H 2 O 2 -CNT < O 3 -CNT. • O-CNTs displayed better colloidal stability than pristine CNT in solutions containing Na+, K+ or Mg2+. • Increased hydrophilcity and more negative surface charges promoted the colloidal stability of O-CNTs. • In presence of Ca2+, O 3 -CNT exhibited the poorest colloidal stability due to cation-bridging effect. Capsule : Colloidal stability of CNTs relays on the intricate interplay between their surface O-functional groups and solution chemistry factors. [ABSTRACT FROM AUTHOR]

This paper presents a broadband resistively loaded modified dipole (RLMD) with an overlapping ellipses profile for radiation enhancement of impulse systems. Based on the equivalent circuit model, a simple method is introduced and analyzed to improve the impedance matching performance of a printed resistively loaded dipole (RLD) by replacing the metal strip with an elliptical profile metal strip. Following this method, a tapered resistively loaded dipole consisting of several resistors and equally separated metal strips with a profile of three overlapping ellipses is proposed. To further improve the impedance matching performance of the proposed antenna, the normalized Euclid distance (NED) is employed to vary the size and position of each ellipse. To verify the performance, the proposed antenna is fabricated and measured. The measured reflection coefficient of the antenna covers from 390 MHz to 10 GHz, which is consistent with the simulated results. In addition, the transmission performance of the proposed antenna is analyzed in the time domain by measuring it with two identical antennas. The received signal amplitude of RLMD is 5.74 dB higher than that of RLD, which is consistent with the simulated results. Therefore, the proposed antenna is appropriate for enhancing the radiation performance of impulse systems. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFASs) have been found to be widely present in soil. Dissolved organic matter (DOM) in soil are supposed to greatly affect the bioavailability of PFASs in soil. Herein, hydroponic experiments were conducted to understand the impacts of two kinds of typical DOM, bovine serum albumin (BSA) and humic acid (HA), on the uptake and translocation of legacy PFASs and their emerging alternatives, perfluorooctane sulfonic acid (PFOS), perfluorooctane acid (PFOA), perfluorohexane sulfonic (PFHxS) and 6:2 chlorinated polyfluoroalkyl ether sulfonate (6:2 Cl-PFESA) in wheat (Triticum aestivum L.). The results indicated that both HA and BSA significantly inhibited the bioaccumulation and translocation of PFASs in the roots and shoots of wheat, and the impacts of BSA were greater than HA. This difference was explained by the greater binding affinities of the four PFASs with BSA than with HA, as evidenced by the equilibrium dialysis and isothermal titration calorimetry (ITC) analyses. It was noting that inhibition impacts of the BSA-HA mixture (1:1) were lower than BSA alone. The results of Fourier transform infrared (FT-IR) spectroscopy and excitation-emission matrix (EEM) fluorescence spectroscopy suggested that HA could bind with the fluorescent tryptophan residues in BSA greatly, competing the binding sites with PFASs and forming a cover on the surface of BSA. As a result, the binding of PFASs with BSA-HA complex was much lower than that with BSA, but close to HA. The results of this study shed light on the impacts of DOM in soil on the bioaccumulation and translocation of PFASs in plants. [Display omitted] • The uptake and translocation of PFASs in wheat were inhibited by HA and BSA. • The inhibition effect in the mixture of HA and BSA was lower than BSA alone. • The inhibition effect was due to the strong binding of PFASs with HA and BSA. • The binding affinities of the PFASs with BSA were greater than HA. • HA reduced the binding affinities of PFASs and BSA due to competition. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a design method proposed to design an active disturbance rejection control for the antenna pointing control of a large flexible satellite system. A simplified dynamics model is established using Euler–Lagrange and used to analyze the dynamic stability of the antenna system. The capturing strategy of the antenna is configured and the inner and outer loops of the active disturbance rejection control are then designed to improve pointing accuracy and rotation speed. The design of the active disturbance rejection control is verified through numerical simulation. Simulation results indicate that the proposed method can be used to achieve high pointing accuracy and rotation speed. [Copyright &y& Elsevier]

Majority of the oilfields in the Hongshanzui region are small and complex fault block reservoirs, and the evolution of the sedimentary system under the sequence stratigrapic background has been a controversial topic. Six middle-term base-level cycles were divided, and eight types of lithofacies assemblages were recognized based on the stacking patterns and volumetric partitioning according to the core, well logs, and seismic data correlated with the field investigation of outcrops. Furthermore, the evolution of the sedimentary system under the sequence stratigraphic framework was clarified. Among the six middle-term base-levels, MSC1 belongs to the retrogradational system tract, and the sediment distribution exhibits the characteristics of "large plain and small front." MSC2 belongs to the transgression system tract, and the sediment distribution exhibits has the characteristics of "small plain and large front." In the case of MSC5 and MSC6, the sediment distribution exhibits the characteristics of "dominant channel and repeated channel-switching." Further, the controlling factors of tectonic, base level, climate, and minerals are discussed.This research has been applied to the exploration and development of the Hongshanzui oilfield, and a certain benefit has been achieved. • Sequence-stratigraphic framework is constructed. • Filling and sedimentary models are established. • The base-level were controlled by alicyclic and autocyclic processes. • The controlling factors of the sedimentary evolution of early-middle Jurassic were discussed. [ABSTRACT FROM AUTHOR]

Gravity flows were commonly developed in subaqueous, steep slopes in lacustrine basins, which show distinct sedimentary records due to different flow behaviors and trigger mechanisms. Outcrops of the Lower Cretaceous deposits on the Lingshan Island are well exposed to illustrate flow transformations between turbidity currents and debris flows in shallow water and basin floor in a lacustrine basin. Outcrop sections were carefully measured to characterize sedimentary records of the gravity flows. Facies associations include laminated mudstone (FA1), deformed silty mudstone (FA2), massive very-fine sandstone with rip-up mud clasts (FA3), graded very-fine sandstone with (partial) Bouma sequences (FA4), massive gravelly sandstone with rip-up mud clasts (FA5), gravelly sandstones with partial Bouma sequences (FA6), and cross-stratified pebbly coarse-grained sandstones (FA7). Trigger mechanisms for the gravity flow include mainly plunging of hyperpycnal river discharges and earthquakes, which both induced failure of delta front/slope and the consequent debris flows/turbidity currents. Flow transformations occurred both at the shallow water and basin floor, which produced distinct sedimentary structures, stacking patterns, and architectural units. The high-density hybrid event beds (HEBs) with both gravels and mud clasts overlaid by sandy turbidites were mainly induced by floodwater from the active river mouths of deltas, generating fast-moving debris flows and deceleration of turbidity currents. Damping of turbidity currents and deceleration of muddy debris flows due to high cohesion induced low-density turbidites were overlaid by HEBs, showing thin-bedded, lateral extended sandy beds on the basin floor. [ABSTRACT FROM AUTHOR]

• A three-stage alluvial fan pattern was built since MIS3. • Cold-dry conditions promote the aggradation of debris flow deposits. • Warm-humid climate leads to perennial streamflow on the fan surface. • Climate is the main factor controlling the evolution of Xiangpi fan. Alluvial fans in the piedmont zones of mountains respond most rapidly to tectonic activity, base-level conditions, and climate changes. These allogenic signals are effectively recorded by the external morphology and internal sedimentary characteristics of the fan. Based on field survey interpretation and integrated optically stimulated luminescence (OSL) chronology, we selected a case study of the modern Xiangpi Fan on the south bank of Lake Qinghai, NE Tibetan Plateau, and built a three-stage alluvial fan pattern since Marine isotope stages 3 (MIS3), namely, the debris flow lobe building stage (DFLBS), aeolian building stage (ABS), and streamflow reworking stage (SRS). The climatic indicators, such as the total organic carbon (TOC) flux, precipitation, and sediment particle size flux, are highly correlated with the above stages, indicating that the sedimentary process and changes in fan morphology effectively record orbital climate changes in the Lake Qinghai basin. During the DFLBS, the cold-dry climate accelerated the sediment yield sufficiently, leading to many coarse-grained sediments and low TOC flux being imported into the basin through debris flow processes. During the ABS, the extreme dry-cold climate caused the stagnation of fan development, and aeolian processes dominated the transport of fine sediment. In the SRS, warm-humid conditions led to limited sediment yield and perennial stream power, which promoted the transport of fine-grained material and TOC to the basin by braided–meandering channels. This study provides an excellent case showing how an alluvial fan responds to climate oscillations through changes in sedimentology and geomorphology. [ABSTRACT FROM AUTHOR]

Abstract This paper presents a receding horizon implementation of sequential convex programming for the spacecraft six-degree-of-freedom close proximity to a non-cooperative target satellite. With linearized relative translational dynamics and newly derived discrete rotational equations in terms of modified Rodrigues parameters, nonlinear system dynamics of the original optimal guidance and control problem for proximity are converted into convex ones for sequentially planning. The nonconvex constraint on field-of-view of the visual sensor pointing with coupled attitude and relative position is then approximately relaxed as a convex standard second-order cone, and concave spherical and ellipsoidal obstacle regions respectively around the target's body and solar arrays are convexified by affine constraints in terms of tangent planes. The original nonlinear optimal guidance and control problem is accordingly transformed into a series of second-order cone programming sub-problems via iteratively successive convexification with the trust region constraints, and sequentially solved using disciplined convex programming method. A close-loop guidance and control using the proposed sequential convex programming scheme is then demonstrated by means of receding horizon to robustly drive the spacecraft maneuvering close to the target. Numerical simulations and results reveal that the proposed method provides rapid and reliable guidance and control performance for six-degree-of-freedom close proximity and shows the potential for on-board implementations in real-time applications. [ABSTRACT FROM AUTHOR]

Abstract To overcome the low capacitance of carbon foam and achieve a high utilization of polyaniline (PANI) pseudocapacitance, graphene nanosheets are filled into carbon foam framework to form a scaffold, and subsequently growing PANI nanofibers to prepare a ternary composite. In this material, carbon foam provides three-dimensional macroporous conductive framework, graphene nanosheets on the carbon foam framework support the deposition of PANI and increase the PANI loading, while much PANI nanofibers contribute a high pseudocapacitance. Therefore, this rationally designed ternary composite not only achieves a high PANI loading of 85.5%, but also exhibits a high specific capacitance and a high utilization of PANI capacitance. As self-supporting electrodes in a symmetrical two-electrode supercapacitor, a high capacitance of 868.5 F g−1 is achieved, in which, the capacitance contributed by PANI reaches 1003 F g−1, more than a half of its theoretical value, furthermore, the capacitance retention is 94.1% after 2000 cycles at 10 A g−1. The design principle of this ternary composite is simple and facile, which can be extended to prepare other nanocomposites containing metal oxides, sulfides, etc. for potential electrochemical applications. Graphical abstract Image 1 Highlights • Graphene nanosheets loading on the CF framework serving as a porous scaffold. • CF@RGO/PANI ternary composite is designed for symmetric supercapacitors. • Capacitance of CF@RGO/PANI-0.5 (85.5 wt% PANI) is 868.5 F g−1 at 1 A g−1. • Capacitance contributed by PANI nanofibers reaches 1003 F g−1 at 1 A g−1. [ABSTRACT FROM AUTHOR]

Abstract Six novel dinuclear Ru(II)-arene complexes [Ru 2 (η 6- p -cymene) 2 (1,3- bib) 2 Cl 2 ]× 2 ·Solvent (X = Cl− (1), I− (2), NO 3 − (3), BF 4 − (4), PF 6 − (5), CF 3 SO 3 − (6); 1,3- bib = 1,3-di(1H-imidazol-1-yl) benzene) were synthesized and fully characterized by FT-IR, 1H NMR, ESI-MS, Elemental Analysis (EA) and Powder X-ray Diffraction (PXRD). Single crystal X-ray diffractions studies showed that 3 and 4 have rigid bowl-like structures, where one counter-anion (NO 3 − for 3 and BF 4 − for 4) was trapped inside the cavity to balance the charge, respectively. Even complexes 1 – 6 showed only moderate or little anti-proliferative activity toward cancer cells, strong interactions with DNA molecules through intercalation, however, were confirmed by UV-Vis, CD and fluorescence spectroscopy. Apoptosis and cell cycle arrest studies for complex 2 with cancer A549 cells indicated concentration-dependent late apoptosis and the G1/G0 phase arrest. Interactions with the tripeptide glutathione (γ-L-Glu-L-Cys-Gly, GSH) might explain the relatively low antiproliferative potency of these complexes. This class of rigid dinuclear cations hold potential as DNA-targeting anticancer agents if their uptake and delivery could be under controlled. Graphical abstract Six new dinuclear Ru(II)-arene complexes containing a rigid imidazole-bridging ligand and anion-binding cavity exhibit strong interactions with DNA and antiproliferative activity which depends on the bound anion. Unlabelled Image Highlights • 6 Novel dinuclear Ru(II)-arene complexes with rigid bidentate ligand • An anion trapped inside the cavity of bowl-like structure. • Strong interactions with DNA and GSH • Anti-proliferative activity • Late apoptosis and the G1/G0 phase arrest [ABSTRACT FROM AUTHOR]

This paper addresses the problem of stochastic trajectory planning for 6-DOF spacecraft close proximity in the presence of external disturbances and initial state uncertainties. Nonlinear chance constraints on collision avoidance, docking corridor, sensor field-of-view, and control magnitude are considered in the corresponding optimal control problem. Nominal trajectory along with affine feedback controller that restricts the dispersion caused by disturbances are optimized simultaneously. The nonlinear stochastic dynamics are transformed into equality constraints on the first two statistical moments of the random states by linearization and discretization, and further, the non-convex covariance update equation is relaxed to a semidefinite cone constraint. The nonlinear path chance constraints are first approximated by affine chance formations, and then are convexified by introducing auxiliary variables instead of direct linearization of the covariance matrix. Combined with the tail bound of sub-exponential random variables, the constraints on control input are replaced with conservative deterministic inequalities. The sub-optimal solution to the original problem is obtained by iteratively solving a series of semidefinite cone programs. The effectiveness of the proposed framework is verified using numerical simulations. • The state-triggered chance constraint is used to describe multi-stage maneuver. • The update equation for covariance is relaxed to semidefinite cone constraint. • A strategy is given to convert nonlinear chance constraint into convex form. • A theorem is given to convert chance control constraint into deterministic form. [ABSTRACT FROM AUTHOR]

With the aid of modern sedimentology, seismic geomorphology, and the comprehensive analysis of geophysical data and core data from more than 10 wells, the Qingshankou Formation has been divided into 3 long-term cycles and further into 6 medium-term cycles in the Qijia area, Songliao Basin. The 3 long-term cycles, SQ1, SQ2 and SQ3 correspond to the members Qing I, Qing II and Qing III of the Qingshankou Formation, spanning 11.5 Ma during the Late Cretaceous. The time scale of the medium-term cycles, which are subunits of the long-term cycles, is approximately 0.5–1.5 Ma with thicknesses ranging from 45 m to 116 m. A shallow-water delta that consists of high-maturity fine-grained sandstone developed in the Qingshankou Formation. The scour surfaces reflect strong flow action, and the parallel bedding and large-scale cross bedding are well developed. Distributary channel sandstones are well developed in the shallow-water delta depositional system, in which a single channel can be several meters thick. The cumulative thickness of the distributary channels can reach tens of meters across a large area, extending tens of kilometers to the center of the lacustrine basin. The development of the subaqueous distributary channel of the shallow-water delta is closely related to base level (lake level) changes. In the early stage of a rising half-cycle and the late stage of a falling half-cycle, the fluviation is significant and the well-developed channel sandstone can extend towards the center of the lacustrine basin more than 50 km, with large cumulative thicknesses of compound sandbodies (17–28 m) and high sandstone-to-strata ratios (78–88%). In the late stage of a rising half-cycle and the early stage of a falling half-cycle, the lake level is high and the fluviation is weak, resulting in a distributary channel extent of less than 30 km, small cumulative thicknesses of compound sandbodies (5–12 m) and low sandstone-to-strata ratios (22–45%). The delta front can be divided into the inner front and the outer front. The subaqueous distributary channels in the inner front have good continuity and extend further, whereas the subaqueous distributary channels in the outer front have poor continuity, and sheet sand is well developed. Therefore, a shallow-water delta generally shows features including (1) sedimentary structures formed by strong currents, (2) stacked fining upward rhythm, (3) subaqueous distributary channels well developed, (4) delta front divided further into an inner and an outer front. There was a relatively good linear relationship between the thickness of the sandbody based on the well data and the maximum amplitude of the seismic trace next to the well. The reddish amplitude of the seismic attribution suggests thicker channel sandbodies (4–9 m), whereas the light amplitude of the seismic attribution indicates thinner channel sandbody (1–4 m). Of the two typical sedimentary models for shallow-water deltas, delta plains develop well in humid climates and delta fronts develop well in arid climates, both of which are found in the Qijia area, Songliao Basin. Stratal slices from seismic geomorphology are applied to display the branchlike sandstone dispersal patterns of the shallow-water delta and the broad distribution characteristics. This study also notes that the delta front distributary channel sandstone, which is near an oil source and faults, would be a favorable exploration target. [ABSTRACT FROM AUTHOR]

The Bohai Bay Basin, a typical intracontinental rift basin, records East Asia's kinematic plate history during the Cenozoic. The rifting process was driven by the counterclockwise rotation in the direction of the Pacific Plate subduction. From the early Eocene to the Oligocene, the rifting process can be divided into three stages: extension initiation, peak extension, and post-extension. The corresponding rifting rate was calculated based on 40Ar-39Ar data. Then, the provenance area evolution of the above three rifting stages was established by combining the detrital zircon U–Pb data and heavy mineral assemblage data (ZTR, GZi, and ATi). According to the results calculated by 40Ar/39Ar analysis, the topography of the sink area in the western Bohai bay basin was characterized by moderately rising subsidence rates (100 m/Ma) during the extension initiation stage (Paleocene-Early Eocene), when surface drainage was restricted to a limited area with steep channel slopes. During this stage, referring to the core description and seismic interpretation results, the fan delta distributes most of the sediment, most of which migrates from the proximal region. Until the peak extension stage, the source-sink system develops as the rate of subsidence increases (200 m/Ma), making the sink area larger, and this period involves multiple types of pathways, including synsedimentary faults and erosional valleys. Sediments from Taihang Massif and Jiaoliao Massif infill the subsidence zone at the distal end. Then, in the post-extension stage, the source-sink systems involve a multi-provenance area (i.e., sourcing from both proximal and distal areas), a large sink area, and a gentle channel gradient due to a decrease in subsidence rate (60–80 m/Ma). Catchment relief, sediment migration distance, and average fault displacement were used, and these parameters were related to the sediment supply (Qs) for the three rifting stages. We find that during extension initiation and peak extension, the source-to-sink systems show a high amount of sand influx (Q sand /) and that the ratio Q sand /Qs total shows a proportional relationship with catchment relief and average fault displacement; this relationship is inversely proportional to the catchment-unit area. Also, according to the types of pathways, we classified the source-to-sink systems during this period into three types, steep eroded pathway (Type-I S2S), gentle slope developed with several boundary faults (Type-II S2S), steep slope with observably eroded valleys or fault-troughs (Type-III S2S). The ratio of Q sand /Qs is only related to the sediment migration distance and average fault displacement in the post-extension stage. Besides the above three types of source-to-sink systems, we found that multi-stage faults developed along the slope (Type-IV S2S) predominated during this stage. • Calculated rifting rate in Bozhong Depression. • Identified the provenance area evolution in Bozhong Depression during Paleogene. • Classified four types of Source-to-sink patterns corresponding to the rifting stage. • Put out the dominated factors to S2S system developed during various rifting stages. [ABSTRACT FROM AUTHOR]

Exploring highly stable and active electrocatalyst for hydrogen evolution, oxygen evolution and oxygen reduction reactions is an unremitting target for the supply and storage of sustainable energies. Here, we report a type of oxygen vacancy-rich nanostructure in which uniform CoP/Co 3 O 4 nanoparticles (NPs) are coated and dispersed on an amorphous carbon network (pPVP). This hybrid nanostructure labeled as 'CoP/Co 3 O 4 -fC-pPVP' is synthesized by a pyrolysis-oxidation-phosphatization strategy, which can accelerate charge transfer and improve carrier separation owing to introducing copious oxygen vacancy. Benefiting from the modulated electronic structure and advantage of interfacial and synergistic effect among active CoP, Co 3 O 4 and pPVP layer, the CoP/Co 3 O 4 -fC-pPVP hybrid structure exhibits excellent trifunctional electrocatalytic performance. The scattering wave vector (q) of the samples before and after catalytic reactions remains unchanged from small angle X-ray scattering (SAXS) tests, indicating the stable phase structure. As for CoP/Co 3 O 4 -fC-pPVP, only a very low potential of 1.585 V is needed to reach 10 mA cm−2 in the overall water splitting process. Furthermore, the peak power density of CoP/Co 3 O 4 -fC-pPVP-based Zn-air batteries reaches 154 mW cm−2 and the charge-discharge voltage gap almost maintains the initial overpotential after 727 h cycle test. [ABSTRACT FROM AUTHOR]

[Display omitted] • Classify the episodically rifting processes in PRMB according to their rifting rates. • Identified the provenance evolution in the North PRMB during the Eocene-Oligocene. • Quantitative analysis of the dominated factor to the S2S system developed. Pearl River Mouth Basin (PRMB) is a typical episodically rifting basin, and its sediment records exhibit a multistage infilling process. To build the coupling relationship between the spatial variability of tectonic movement and sediment dispersal pattern, we character the source-to-sink system distribution within continental margin and analysis their dominated factors with quantitative statistical methods. First, we identify the faults and calculate the rifting rate by interpreting the two-dimensional (2D) seismic data and zircon or apatite fission-track data (ZFT/AFT). Accordingly, based on the various trending of the rifting rate evolution, we classified rifting process episodically into three patterns: accelerated rifting decelerated rifting, and uniform rifting. Then, we integrated the data available on detrital zircon U–Pb, rare earth element, and heavy mineral assemblage to identify the responding S2S components associated with the above various rifting processes. Results show that in the first tectonic stage during the early Eocene, the sediments were mainly sourced from an intrabasin provenance area, whereas in the late Eocene to the Oligocene, the paleo-Pearl River provided the sediments to the sink area. We restore the facies association of the sink area by studying the core samples, electric well logs, and three-dimensional (3D) seismic data. During the accelerated and uniform rifting processes, coarse-grained deposited along the boundary faults, which includes the fan delta and subaqueous fans. During decelerated rifting, the depositional environment was dominated by braided channels, meandering channels, and tide-influenced channel accretion. Based on the quantitative analysis the relationship between the grain size of the sediment in each S2S segment and the rifting rate, more fine-grained components were preserved in the decelerated rifting system, while coarse-grained sediments fill the accelerated rifting depression and uniform rifting components. Furthermore, the sediment supply and relative height can influence the volume of the S2S system in the uniform rifting system. In the decelerated rifting basin, the sediment supply is the major factor associated with the development of S2S, whereas the relative height is the major factor associated with the accelerated rifting basin. [ABSTRACT FROM AUTHOR]

Developed on the North China Craton, the intracratonic Ordos Basin contains a complete Paleozoic-to-Cenozoic sediment record, allowing for long-term paleoenvironmental and climate change investigation. During the Carboniferous–Permian period, convergence between the North China block and the paleo-Yangtze plate to the south resulted in a general marine regression characterized by a series of second-order transgression/regression cycles diachronous along the eastern margin of the Ordos. However, the detailed mechanisms that induced these cycles, as well as the associated paleoecological changes, remain unknown. In this study, we integrate multiple indices, including δ18O and δ13C, rare earth element (REE), paleontological assemblages, and clay content (w (chlorite + kaolinite)/ w ((Illite) ratio) planar distribution, to restore the paleo-water depth distribution. These parameters are then used to reconstruct the paleo-sea level from the Pennsylvanian to the middle Permian. We conclude that the direction of second-order transgression/regression was mainly toward the east during the Pennsylvanian–early Permian and switched clockwise toward the north during the middle Permian. We suggest that the second-order cycles, diachronous in space and time, are mainly linked to local variations in sediment supply and regional uplift. Using detrital zircon U–Pb data and the REE and trace element content and heavy mineral assemblages (HMA), we estimate the sediment provenance area. The sediment volumes deposited in the basin through time are obtained using 2D seismic data. During the Carboniferous, the coarse-grained sediments deposited in the eastern Ordos were derived from the uplifting Helan Mountain (Qiandam–Qilian orogenic belt). By the middle Permian, the detrital material became multi-sourced, thus issuing the Yinshan range to the north and the Qinling range to the south. We then integrate the description of numerous core samples with electric log and 2D seismic data to reconstruct the sediment facies associations across the first-order regression from the Carboniferous tidal flat depositional system to the middle Permian prograding fluvial delta system. According to the transfer of the glacial epoch, the sedimentation rate, and the transgression/regression rate above, we classify the evolution process into three patterns: low-transgression rate and less-sediment supply pattern (the late Carboniferous), high regression rate and mass sediment supply pattern (the north block during the early Permian), and low regression rate and mass sediment supply pattern (the south block during the Sakmarian stage). Lastly, with the quantitative calculation of the source-to-sink (S2S) parameters, including the S2S system volume and the elevated height of regional uplift with the 2D seismic data, we propose the mechanism of transgression/regression in the Ordos Basin, responding to the above three pattern s. The first pattern was controlled by regional uplift, whereas the second pattern was controlled by sediment supply. As to the third one, uplift and sediment supply could affect the transgression/regression process. • Identified provenance area of the eastern margin of the Ordos Basin during the Pennsylvanian to the early Permian. • Reconstructed the clockwise evolution process of the relative sea level in the study area. • Identified different types of source-to-sink systems insight from the sea level and sediment supply. • Proposed an integrated method to determine the dominating factors influencing the relative sea level. [ABSTRACT FROM AUTHOR]

Sedimentary features of a source-to-sink (S2S) system produce distinct responses to diverse bedrock types (i.e., silicate and carbonate rocks) in the catchment; these majorly influence the sediment flux, volume, and grain size in the sink area. By comparing a modern S2S system of Holocene Erhai Lake Basin (ELB) (in southwestern China) and an ancient S2S of Eocene western Offshore Bohai Bay Basin (OBBB) (in eastern China), we investigated the differences and proportional ranges among sandy sediment flux (Q f) and sediment discharge (Q s) from catchment associated with diverse bedrock types in a humid and subtropical lacustrine rift basin by combining with the Google-topographic-map, BQART-model, and seismic-geomorphology analysis. Based on geomorphological and 3D visualization analysis, we identified the differences among multiscale catchment-fluvial segments and their sedimentary responses in S2S systems, and then extracted parameters of catchment-unit area (A), catchment relief (R), and total sediment discharge (Q s , calculated by BQART model). Furthermore, we analyzed sediment-dispersal patterns and sandy sediment fluxes in the nearshore (Q f) using regional geologic data, outcrops and the Google Earth database in the Holocene ELB, and using seismic geomorphology in the Eocene western OBBB. Finally, quantitative analysis of the modern and ancient S2S segments was used to investigate the total sandy sediment flux (Q f), which is supplied by >60% of the entire sediment discharge (Q s) for catchments with silicate bedrocks (e.g., metamorphic rock and granite), while the ratio Q f /Q s corresponding to carbonate bedrocks is less than 30%. Additionally, the ratio Q f /Q s for catchments with mixed silicate carbonate bedrocks ranges between 30% and 60%. These results not only provide a new perspective for investigating sandy sediments in a subtropical lacustrine rift basin, but also yield implications for better understanding of continental S2S system theory for diverse bedrock types. • Divide the modern and ancient source-to-sink (S2S) segments into multi-order catchment units and fan-lobes. • Extract the kernel parameters of sediment discharge from catchments and sediment flux of proximal fans. • Discuss the proportional range between sandy sediment flux and sediment discharge associated with diverse bedrock types. • Establish a flux model of source-to-sink segments with diverse bedrock types in subtropical lacustrine rift basins. [ABSTRACT FROM AUTHOR]

During the Eocene, the western Shaleitian Uplift and its adjacent sags constituted a source-to-sink (S2S) system on an active lacustrine basin margin with a steeply dipping boundary fault. We integrated a range of data types with subsurface observations from the western offshore Bohai Bay Basin (OBBB) that allowed us to quantify the size and classification of catchment-fluvial segments, and analyze the sedimentary architecture and sediment fluxes of the proximal fan-delta system. We then discovered quantitative coupling relationships among the parameters of ancient source-to-sink segments. Results show that in the study area the bedrock of the western Shaleitian Uplift is composed of Proterozoic migmatized granites or granites. On the basis of paleogeomorphology reconstruction, we established classification standards for multi-scale catchment units, divided the provenance into four third-order catchment units, obtained quantitative parameters of the catchment-unit area (A), catchment relief (R), and total sediment discharge (Q s , calculated by BQART model) and then confirmed the scales and distribution (cross-sectional area, S cs) of sediment-transport pathways. Furthermore, we analyzed tectonic subsidence, sediment-dispersal patterns, and sediment fluxes of fan-delta systems (Q f) using seismic sedimentology in the third member of the Eocene Shahejie Formation (Es 3). Finally, we used quantitative, multivariate, statistical analysis of the parameters involved in the source-to-sink segments to (1) show the proportional range between total sediment fluxes of fan delta (Q f) and sediment discharge (Q s) from catchment (largest rate of Q f /Q s in the lower part of Es 3 , smallest rate of Q f /Q s in the middle part of Es 3 , and the range from 30% to 70%) and (2) arrange the mainly controlled parameters in terms of their importance (i.e., rate of tectonic subsidence, catchment area, catchment relief, and cross-sectional area of sediment-transport pathway are listed in order of importance). This study can provide an effective way of quantifying and ordering the parameters important in that controlling a complex ancient source-to-sink system, thus helping to achieve an understanding of the process of tectono-sedimentary evolution on a rifted, lacustrine-basin margin. • Divide the catchment segment into different orders and pick up the main parameters. • Indicate the sediment-dispersal patterns and sediment flux of fan-deltas in an active extensional setting. • Reveal the correlation and ordering of multiple important parameters of ancient source-to-sink in a rift basin margin. [ABSTRACT FROM AUTHOR]

In multi-phase rift basins, the links between fault activities and sequence stratigraphic architectures are still poorly understood compared to single-rift basins. The purpose of this work is to give implications for tectono-stratigraphic signatures in multiphase rifts based on seismic data from the Zhu-3 Depression in the Pearl River Mouth Basin, China. Stratigraphically, three composite sequences (CS1-3) defined by major unconformities in the Paleogene successions of the Zhu-3 Depression are interpreted, with each one subdivided into two or three third-order sequences. Regional unconformities and basin configurations indicate two episodic rift phases, termed rift phase 1 (formed CS1), and rift phase 2 (formed CS2) followed by a lithospheric breakup phase (formed CS3). From rift phase 1 to rift phase 2, the basin evolved from small-sized, independent half-grabens into relatively large-scale grabens and finally a dish-like basin configuration. Fault displacement and stratigraphic stacking patterns revealed three distinctive structural stages of rift phase 1: rift initiation (WC-SQ1), rift development (WC-SQ2), and rift termination (WC-SQ3) stages. However, an immediate decrease in fault activity was recorded in the rift phase 2. Immediate strain localization under rotated extension fields during episodic rift phases led to variabilities in tectono-stratigraphic architectures. In turn, this transition may likely contribute to interpreting the depositional pattern from balanced infill during rift phase 1 to an overfilled pattern during rift phase 2 as well as the breakup stage in response to possible enhanced sediment supply. This work enhanced our understanding of additional hydrocarbon evaluations in the Zhu-3 Depression, South China Sea. • The Eocene-Oligocene sequence framework in the Zhu-3 rift are systematically reported. • Fault pattern, basin geometry and drainages basin in episodic rift phases are illustrated. • Tectono-stratigraphic signatures of three rift cycles in the Zhu-3 rift are proposed. • Controls of boundary fault arrays evolution on two-phase rift development are discussed. [ABSTRACT FROM AUTHOR]

Abstract Mitigation of space debris draws much concern today since its steadily increasing number and the consequent increased risk of space activities. Among all the active debris removal strategies, tethered space-tug is considered as a promising method due to its safeness of capture and dynamic stability of pull strategy. Although promising, challenges remain in its position and attitude control especially when the target is tumbling, which may cause damage to the appendages or result in collisions. This paper addresses the problem of position and attitude control of a tethered space-tug system with only tether tension available for the target. Based on Takagi-Sugeno fuzzy technology, a guaranteed cost guidance and control law is obtained by solving a set of linear matrix inequalities. The effectiveness of the guidance and control strategy is validated by numerical simulations. [ABSTRACT FROM AUTHOR]

Attribute weight assignment plays a key role in multiple attribute decision making (MADM). For the issue of labeled multiple attribute decision making (LMADM), the existing methods of attribute weight determination that have been well developed for MADM usually ignore or do not take full advantage of the supervisory function of labels. As a result, the weights produced by these methods may not be ideal in practice. To make up for this deficiency, this paper develops an objective method based on Bayes risk. Specifically, the LMADM problem is first put forward, then a Gaussian kernel based loss function is proposed to cope with the drawback that the loss function in Bayes risk is usually determined by experts. Meanwhile, Mahalanobis distance and fuzzy neighborhood relationship are employed to measure the fuzziness of data set. Finally, a number of experiments, including the comparison experiments on UCI data and the effectiveness evaluation of fighter, are carried out to illustrate the superiority and applicability of the proposed method. [ABSTRACT FROM AUTHOR]