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Recently, researchers have demonstrated, both theoretically and experimentally, that low-dimensional version of conventional leaky waves, known as "flatland leaky waves" (FLWs). FLWs can be supported by planar junctions of metasurfaces and are completely confined to a plane. Here, we design a structure that places an equivalent reactance surface near the transmission line to excite the FLWs. By properly designing the geometry of the unit cell, conditions can be created for faster surface waves (SWs) to excite slower SWs on the surface, resulting in the desired form of two-dimensional (2D) leaky-wave radiation. A sample was fabricated and measured, and both the simulation results and the experimental results yielded the desired results. Finally, we design the equivalent impedance surface model on which we can also observe the 2D FLWs. Our research not only deepens the understanding of the phenomenon of FLWs but also brings the application of equivalent reactance surfaces in the field of electromagnetic phenomena research to a higher level. [ABSTRACT FROM AUTHOR]

This paper proposes a trajectory-optimization problem for spacecraft close proximity to a noncooperative target, aiming at the generation of a six-degree-of-freedom (DOF) trajectory with the fuel-optimal objective value and considering multiple constraints on the control magnitude, line-of-sight, and glide-slope. The line-of-sight and glide-slope constraints are coupled between translational and rotational motions. The dual quaternion is an effective method for establishing the translationally and rotationally coupled model, because it can represent the translation and rotation in an integrated manner. Therefore, in this study, the trajectory-optimization problem of spacecraft close proximity coupled with position and attitude is established using dual quaternions. Next, the close-proximity trajectory-optimization problem is converted into a nonlinear programming problem, which can be solved efficiently using well-developed algorithms such as convex optimization. However, the zero-order hold used in the discrete method of convex optimization is an equidistant dispersion, which cannot guarantee the satisfaction of constraints between discrete points. Therefore the pseudospectral convex method is proposed using nonequidistant collocation points to mitigate the problem of constraint violation between discrete points and improve the accuracy and computational efficiency of the algorithm. The proposed algorithm can be applied to tasks such as rendezvous and docking with noncooperative targets and close proximity. Finally, the effectiveness of the proposed method was validated via numerical simulation, and the results were compared with those of the existing approach, GPOPS. The results indicate that the proposed algorithm is superior to GPOPS in computational efficiency and objective values. [ABSTRACT FROM AUTHOR]

Nowadays, deep representations have gained significant attention due to their outstanding performance in a wide range of tasks. However, the interpretability of deep representations in specific applications poses a significant challenge. For instances where the generated quantity matrices exhibit symmetry, this paper introduces a variant of deep matrix factorization (deep MF) called deep L p smooth symmetric non-negative matrix factorization (DSSNMF), which aims to improve the extraction of clustering structures inherent in complex hierarchical and graphical representations in high-dimensional datasets by improving the sparsity of the factor matrices. We successfully applied DSSNMF to synthetic datasets as well as datasets related to post-traumatic stress disorder (PTSD) to extract several hierarchical communities. Specifically, we identified non-disjoint communities within the partial correlation networks of PTSD psychiatric symptoms, resulting in highly meaningful clinical interpretations. Numerical experiments demonstrate the promising applications of DSSNMF in fields like network analysis and medicine. [ABSTRACT FROM AUTHOR]

Non-negative matrix factorization (NMF) is widely used as a powerful matrix factorization tool in data representation. However, the traditional NMF, measured by Euclidean distance or Kullback–Leibler distance, does not take into account the internal implied geometric information of the dataset and cannot measure the distance between samples as well as possible. To remedy the defects, in this paper, we propose the NMF method with Earth mover's distance as a metric, for short GSNMF-EMD. It combines graph regularization and L 1 / 2 smooth constraints. The GSNMF-EMD method takes into account the intrinsic implied geometric information of the dataset and can produce more sparse and stable local solutions. Experiments on two specific image datasets showed that the proposed method outperforms related state-of-the-art methods. [ABSTRACT FROM AUTHOR]

The formation of vertical sedimentary succession of a delta in the arid and semi-arid basin-margin progradation dramatically depends on the variation of sediment flux and accommodation, but the discontiguous record of signals tends to exist enormously variable, which renders the bulk record of microfacies difficult to quantify from the vertical sedimentary succession. We analyzed the 18 vertical sedimentary successions collected from 18 field trenches of a lake delta by the cusp-catastrophe model, allowing detailed mapping of microfacies. The present detailed study indicates the suitability of cusp-catastrophe theory for explaining vertical sedimentary succession in the BWH (Bawanghe) delta. Three equilibrium states of processes responsible for the deposition of the BWH delta's evolution were established: sandy-dominated upper leaves primarily exhibit the delta plain; sandy/muddy-dominated lower leaves present the delta plain and pro-delta; and sandy-dominated middle leaves which commonly developed the delta front. The result of analysis shows that the reliability of the cusp-catastrophe model to identity mutation of vertical sedimentary succession exceeds 50 %, and to identity microfacies transitions with a precipitation periodicity exceeds 70 %. These cognitions support the previous view that changing precipitation results in an abrupt change in margin progradation. Simultaneously, the study gives new insights into the microfacies quantification of lake deltas and reveals the influence of crest value changes of precipitation on vertical sedimentary succession can be understood from the dependence of microfacies distribution on the change of sediment flux and accommodation. [ABSTRACT FROM AUTHOR]

The pre-hydrolysis liquor (PHL) produced during pulp dissolution and biomass refining is mainly composed of hemicellulose and lignin, and it is a potential source for production of value-added materials and platform chemicals; however, their utilization has been a serious challenge. In this study, we proposed a green and simple strategy to simultaneously prepare size-controlled functional lignin nanoparticles (LNPs) and levulinic acid (LA) from PHL as the raw material. The as-prepared LNPs exhibited remarkable stability thanks to the presence of saccharides with abundant oxygen-containing groups and surface charges, which prevented aggregation and maintained long-term storage stability. Trace amounts of the LNPs (≤ 0.2 wt%) could stabilize various Pickering emulsions, even with oil-to-water ratios as high as 5:5 (v /v). Subsequently, the remaining PHL was directly used to produce LA without adding a catalyst; under optimal conditions (160 °C and 1 h), the yield of LA was 56.3 % based on the dry saccharide content in the raw PHL. More importantly, p -toluenesulfonic acid (p -TsOH), the only reactive reagent used during the entire preparation process, including the two preparation steps of the LNPs and LA, was reusable, and the recovery rate was >70 % after five cycles. Overall, this green and simple strategy effectively and comprehensively utilized the PHL and showed potential for producing biobased nanomaterials and platform chemicals. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] The bifunctional efficient electrocatalysts for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are in urgent need for the advanced overall water splitting (OWS) device. Restricted by the thermodynamic limitations of the catalytic active center for OER and the reaction kinetics limitations induced by the structure of the electrocatalysts, the development of OWS catalysts requires more effort. Herein, a porous carbon-based bimetal electrocatalyst of Mo 0.84 Ni 0.16 -Mo 2 C@NC nanosphere is prepared by hydrothermal treatment of PMo 12 @PVP@Zn/Ni-ZIF which is synthesized via one-pot self-assembled hydrothermal method. Our study confirms that the Mo-Ni alloy and Mo 2 C nanoparticles homogeneously distribute in nitrogen-rich carbon-based materials. Furthermore, the porous structure exposes rich active sites and increases the effective specific area for redox reactions. The obtained Mo 0.84 Ni 0.16 -Mo 2 C@NC catalyst requires low overpotentials of 151 and 285 mV to reach a current density of 10 mA cm−2 towards the water reduction and oxidation in 1 M KOH solution, respectively, and possesses good catalytic stability for one day. This work introduces an advanced method for the synthesis of the bimetal electrocatalyst. [ABSTRACT FROM AUTHOR]

In this paper, a novel compact microstrip patch antenna with a boresight filtering gain response is proposed. The proposed antenna consists of a radiating patch, a ground plane, two pairs of slots respectively etched on the radiating patch and the ground plane, two shorted vias connecting the radiating patch and the ground plane. The slots on the ground plane not only provide a gain null in the lower transition band, but also introduce a new low‐resistance resonance which is beneficial to widen the impedance bandwidth. The slots on the radiating patch provide another gain null in the upper transition band. The two shorted vias are used to further adjust the reflection coefficient and the gain performance of the antenna. Since no extra circuits are introduced, the proposed antenna is compact. A prototype operating at 3.0 GHz was fabricated and measured. It demonstrates that the proposed antenna has a bandwidth of 3.5% and a gain of 6.0 dBi in a profile of 0.015 λ0. At the same time, a good filtering gain response is realized. [ABSTRACT FROM AUTHOR]

A metasurface lens antenna fed by a planar $8\times8$ dual polarized antenna array is proposed and characterized for full-dimensional massive multiple-input multiple-output (MIMO) and multibeam systems at sub-6 GHz bands. The lightweight multilayer metasurface structure consisting of Jerusalem cross elements is used for a planar lens design. The lens antenna with the size of $10\lambda _{0} \times 10\lambda _{0} \times 5\lambda _{0}$ is fed by an $8\times8$ dual-polarized stacked patch array to operate over the range from 5.17 to 6.10 GHz, where $\lambda _{0}$ is the free-space operating wavelength at the center frequency of 5.6 GHz. This article shows the scanning range of ±25° with a maximum gain of 22.4 dBi and the gain variation of 3.3 dB at 5.6 GHz. Beam coverage performance, pattern envelope correlation coefficient, and port isolation properties demonstrate its full-dimension access capability of the antenna. Besides, the multibeam antenna system with high-gain coverage is achieved by beams operating at the same frequencies, while the frequency division multiplexing can be realized for the isolated beams. The proposed metasurface lens antenna, featuring lightweight, compactness, and low cost compared to a 3-D dielectric lens and low-complexity compared to the array scenarios, can be an alternative for fifth-generation (5G) sub-6 GHz frequency bands. [ABSTRACT FROM AUTHOR]

An ultra‐wideband pulse crossover with a reversed polarity channel is proposed, and a time‐domain analysis is utilized to design the crossover and estimate its performance. Two crossed channels are designed based on post‐wall slotline (PWS) and conventional slotline, and one of the two channels provides an output with reversed polarity. At the overlapping region, the PWS degrades to slotline on single layer to improve isolation between channels. Normalized Euclid distance of short pulses is utilized to evaluate the isolating and polarity reversing features of the crossover, and the matrices of normalized Euclid distance are then obtained and applied to the design procedure. The proposed crossover are modeled and fabricated for simulation and measurement, and the simulated and measured results agree well. Minimum of return loss and isolation is more than 12 dB within an ultra‐wide bandwidth from DC to 8.5 GHz. Moreover, in time domain, the proposed crossover shows good performance in pulse transmission, including high fidelity and amplitude ratio of input and output signals. The characteristics of the crossover indicate the practicability in short pulse application, and rectangular pulse transmission performance is evaluated to verify the ability. [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]

Abstract As an excellent free-standing carbon source, commercialized cotton cloth can be carbonized to fabricate conductive carbon cloth composed of hollow carbon microfibers. In view of the hydrophobicity of carbon cloth, a functionalized carbonized cotton cloth (FCC) is prepared by acidification treatment, and acted as a flexible substrate to grow hierarchical SnO 2 nanoclusters by a solvothermal reaction and calcination process. In this SnO 2 wrapped FCC (FCC@SnO 2) composite, the oxygen-containing groups in carbon microfibers provide numerous anchoring sites for growing SnO 2 nanoparticles, meanwhile, the carbon microfibers provide conductive channels for the fast transfer of electrons and ions. The SnO 2 nanoclusters effectively contribute their pseudocapacitance. As free-standing electrodes in a symmetrical two-electrode supercapacitor, the FCC@SnO 2 composite exhibits a higher capacitance of 197.7 F g−1 or 1265.3 mF cm−2 at 1 A g−1, much higher than that of FCC (100.3 F g−1 or 411.2 mF cm−2); furthermore, its capacitance remains 95.5% after cycling for 5000 cycles at 15 A g−1. The FCC@SnO 2 composite is easier preparation and low cost, which can be utilized as self-supporting flexible electrodes for high performance supercapacitors. Graphical abstract Image 1 Highlights • Acidified carbonized cotton cloth is acted as a freestanding flexible substrate. • Hierarchical SnO 2 nanoclusters are wrapping on the surface of carbon microfibers. • FCC@SnO 2 exhibits a capacitance of 197.7 F g−1 or 1265.3 mF cm−2 at 1 A g−1. • Its capacitance retains 95.5% after cycling for 5000 cycles at 15 A g−1. [ABSTRACT FROM AUTHOR]

The East China Sea Shelf Basin was a back‐arc basin located at the active continental margin of the western Philippine Sea Plate. This study explores facies and architectural changes from tide‐influenced deltas to tide‐dominated estuaries in transgressive–regressive cycles, as well as their controlling factors. Cores, wireline well‐logs and seismic data allow the sedimentary architectures and models of the depositional systems to be reconstructed. In the Xihu Depression of the East China Sea Shelf Basin, the stratigraphic sequences of the Eocene Pinghu Formation are interpreted to be dominated by repeated phases of deltaic progradation, but with intervening transgressive phases only thinly developed as bioturbated, open‐marine shelf deposits. The sequences of the overlying Oligocene Huagang Formation, in contrast, are interpreted as stacked, tide‐dominated estuary units, alternating with only poorly preserved regressive half‐cycles because of repeated, strong estuary down‐cutting. The intervening unconformity in the succession corresponds to the Yuquan tectonic movements, which triggered a change from extensional to compressional settings in the Xihu Depression. In the Late Eocene, extension of the Xihu Depression led to moderately high rates of subsidence (163 m Ma−1), and short‐term sea‐level falls led to multiple phases of deltaic progradations. After the Yuquan Movement, Early Oligocene compression brought overall lower rates of subsidence (110 m Ma−1), as well as sea‐level rise and stacked estuary development with significant tidal influence in the infill. The interaction of tectonics, sea‐level change and sediment supply determined the nature of the depositional systems on the shelf during the entire period, whereas the sedimentary processes were key to reworking and shaping the facies distribution, geomorphology and architectures in the back‐arc basin. This research provides an insight into spatial and temporal characterization of deltaic and estuarine systems, contributing to a better understanding of the mechanisms controlling a change in dominant coastline type, despite continued strong tidal influence. [ABSTRACT FROM AUTHOR]

Cobalt disulfide (CoS 2 ) has been revealed as strong adsorption and activation sites for polar polysulfides, which effectively accelerates the redox reactions of polysulfides in lithium-sulfur (Li-S) batteries. As an ideal sulfur host, a three-dimensional (3D) graphene framework is adopted for high-performance Li-S batteries. Considering the special function of the CoS 2 nanoparticles and the advantages of a 3D porous graphene framework, a porous CoS 2 /reduced graphene oxide (CoS 2 /rGO) binder-free sulfur host is prepared by a bottom-up assembly and hydrothermal treatment. The porous rGO film is stacked by interconnected graphene sheets, and the CoS 2 nanoparticles are dispersed on the graphene sheets uniformly, which effectively obstructs the stacking of graphene sheets. As a binder-free sulfur host, the porous CoS 2 /rGO sulfur host combines the sufficient electron conductivity of the porous rGO framework and the sulfur immobilization interaction of the CoS 2 nanoparticles. This host material demonstrates an initial discharge capacity of 993.5 mAh g −1 and a capacity of 806.7 mAh g −1 after 110 cycles at 0.5 C. Both the capacity and cycling stability of the CoS 2 /rGO cathode were greatly improved over that of rGO. Furthermore, the bottom-up assembly approach provides a novel opportunity for preparing self-supporting graphene-based nanocomposite electrodes. [ABSTRACT FROM AUTHOR]

Mud clasts are common in non-marine to marine sedimentary records, however, why lack a widely accepted classification scheme? We propose that it is the relative balance of volumetric abundance, sorting, roundness, and grain size that controls the texture and fabric of mud clasts. Nine distinct types of mud clasts are identified in the study based on quantitatified properties, and fall into two groups coarse-grained and fine-grained. The generation of mud clasts can be assigned to failure, erosion, and/or bioturbation of muddy sediment. These clasts are transported within fluid flows including Newtonian fluids, non-Newtonian fluids, and Bingham plastics (gravity flow and turbidity flow), showing various physical characteristics depended upon the density and viscosity of flows. Newtonian flows with less density and viscosity commonly form mud clasts with mature textures. In non-Newtonian (gravity-driven) flows, mud clasts are normally transported in laminar flows with high density and viscosity, developing matrix-supported mud clasts with immature textures. The study of classification, formation, and transport mechanisms of mud clasts has implications for identifying and interpreting sedimentary environments. [ABSTRACT FROM AUTHOR]

Late Paleozoic strata in the southeastern Ordos Basin comprise targeted reservoirs for tight gas exploration. As a typical intracratonic basin, the Ordos Basin is characterized by low-accommodation space and a complex sediment infilling process, which attracts much attention. During the early Permian, the southeast area was fed by sediments from multiple sediment sources, which makes it difficult to identify the pinch-out of the sand bodies and reconstruct the sediment routing system. In this study, we reconstruct the paleo-topography of the late Paleozoic setting using high-resolution 2D and 3D seismic data. Thus, we identify two types of topography: the eastern block is presented as a semiclosed depression, and the western block is observed as a flat platform. Based on detrital zircon U–Pb data and heavy mineral assemblages, we reconstruct the provenance area and show that early Permian sediments originate from the northern margin of the Ordos Basin and from the northern Qinling orogenic belt in the south. By integrating the trace element contents, carbon and oxygen isotope data and sedimentary structure from core samples, we can observe the paleoenvironment and the corresponding facies associations in these blocks. The eastern block was infilled by a prograding delta; the western block was infilled by a tide-dominated delta or a wavy-dominated delta. By using stratigraphic forward modelling, we find that most sediments in the semiclosed setting are progradational and intensely interacted. In contrast, the sediments in the western block present an open setting, infilled and gently interacted. The fine-grained deposits were not easily preserved due to tidal or wave reworking processes in the shallow-water marine setting, and they were transported into deep-water areas. Furthermore, to explore the dominant factors in a pattern of fluvial–deltaic sand bodies formed in the low-accommodation basin, we rebuild the sediment routing system parameters and plot them on a bubble chart. According to the fitness between the depositional volume and the above parameters, we determine the key factors in the routing systems that formed. The results show that the sediment supply has a high relevance to the depositional volume in a semiclosed setting, such as the eastern block, while the terrain height may drive sedimentation in an open marine setting, such as the western block. We demonstrate that two different infill patterns and different sand-body stacking patterns with multiple sediment sources in a low-accommodation basin may serve as a model for similar settings. [ABSTRACT FROM AUTHOR]

The shallow-water braided deltas are hot topic in global sedimentology. In China, this depositional environment forms an important reservoir and exploration target within the basins. Therefore, geological and sedimentologic settings of the Jurassic shallow-water braided deltas in the Junggar basin of western China have attracted much attention in recent years based on the comprehensive analysis of geological and geophysical data acquired. These braided deltas deposited in the shallow Junggar lacustrine basins with gentle slope gradients and prograded towards to the central basin from northeast to southwest (more than 10 km). This kind of Jurassic delta was characterized by coarse grain-size (sand to pebble), large cross-beddings, discontinuous fining-upward successions vertically, high percentage of sandstone ratios (up to 70%), very unique distributary channels with few distributary mouth bars, and seismic facies of shingled with a progradational reflections. Based on the detailed research on basin evolution and sedimentary characteristics of deltaic sub-facies, this paper presents the relationship between the shallow-water braided deltaic deposition and lithologic traps predicted to be the favorable and explorable lithological traps in the Junggar Basin. [ABSTRACT FROM AUTHOR]

[Display omitted] • A weak-strong coetching strategy is developed for metal–organic frameworks. • Hollow nanopompoms structure is obtained and can be maintained upon pyrolysis. • Pyrolyzed nanopompoms allow for efficient electron transfer applications. • Heterophases increase active sites and promotes electrocatalytic performance. • Nanopompoms catalyst has desirable bifunctional performance for Zn-air batteries. The rational structure and composition design of bifunctional electrocatalysts for oxygen evolution reactions (OER) and oxygen reduction reactions (ORR) is crucial for rechargeable metal–air batteries. Here, we report controlled structural transitions of metal–organic frameworks through a weak-strong competitive coordination strategy for high-performance electrocatalysts. Upon the introduction of potassium ferricyanide (PF) and/or phosphomolybdic acid (POM), cubic zeolitic-imidazole framework-67 (Cube-67) undergoes both chemical and macroscopic morphology changes, i.e., from nanocubes to hollow nanopompoms, where PF and POM act as the weak chelator (i.e., for finer structures) and the strong chelator (i.e., shape-directing agent), respectively. After calcination, the hierarchically structured nanopompoms display tunable and high-performance OER and ORR catalytic activities suitable for Zn–air batteries that display a long-term charge–discharge cycling stability. This work not only holds promise for clean-energy applications but provides a design principle for engineering advanced electrocatalysts by effectively tuning their structural and chemical properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • A weak-strong coetching strategy is developed for metal–organic frameworks. • Hollow nanopompoms structure is obtained and can be maintained upon pyrolysis. • Pyrolyzed nanopompoms allow for efficient electron transfer applications. • Heterophases increase active sites and promotes electrocatalytic performance. • Nanopompoms catalyst has desirable bifunctional performance for Zn-air batteries. The rational structure and composition design of bifunctional electrocatalysts for oxygen evolution reactions (OER) and oxygen reduction reactions (ORR) is crucial for rechargeable metal–air batteries. Here, we report controlled structural transitions of metal–organic frameworks through a weak-strong competitive coordination strategy for high-performance electrocatalysts. Upon the introduction of potassium ferricyanide (PF) and/or phosphomolybdic acid (POM), cubic zeolitic-imidazole framework-67 (Cube-67) undergoes both chemical and macroscopic morphology changes, i.e., from nanocubes to hollow nanopompoms, where PF and POM act as the weak chelator (i.e., for finer structures) and the strong chelator (i.e., shape-directing agent), respectively. After calcination, the hierarchically structured nanopompoms display tunable and high-performance OER and ORR catalytic activities suitable for Zn–air batteries that display a long-term charge–discharge cycling stability. This work not only holds promise for clean-energy applications but provides a design principle for engineering advanced electrocatalysts by effectively tuning their structural and chemical properties. [ABSTRACT FROM AUTHOR]

A postwall slotline (PWS), composed of a bilateral slotline and two metalized via arrays aligned at the slot edges, is proposed and its application in the design of short-pulse tapered slot antennas (TSAs) is investigated. The characteristic impedance of the PWS is derived by a partly analytical and partly empirical method. Compared with the conventional slotline, the PWS has lower available characteristic impedance and larger variation range, which is favorable for meeting diverse design specifications. The PWS is employed in the design of two TSAs with exponential profile and Gaussian profile, respectively. The two tapered PWS antennas are fabricated and their performance in both frequency domain and time domain is investigated. The results show that the TSA based on the PWS is featured by broad bandwidth, low cross-polarization, and good suitability for short-pulse applications. [ABSTRACT FROM PUBLISHER]

• A N-doped carbon confined WC/Co 3 W 3 N/Co@NC is prepared via epitaxial growth and calcination. • Porous yolk/shell structure exposes more active sites and boosts the diffusion of the reactants. • Synergistic effect improves the electrocatalytic performance of water splitting. [Display omitted] Designing high-efficiency catalysts with earth-abundance elements for overall water splitting (OWS) in alkaline electrolyte has been unsettled owing to the non-negligible overpotential of oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). An electrocatalyst with decent HER and OER activities in the same electrolyte is crucial for sustainable energy storage and conversion device. In this work, a nitrogen-doped porous carbon confined yolk/shell OWS catalyst of WC/Co 3 W 3 N/Co@NC has been prepared via calcination polyhedron encapsulation structure PW 12 @ZIF-8 @ZIF-67 generated by the epitaxial method. Because of the optimized chemical composition, the derived WC/Co 3 W 3 N/Co@NC multisite catalyst has outstanding OWS performance in 1 M KOH solution. For example, to reach a current density of 10 mA cm-2, it only needs low overpotentials of 141 and 280 mV for the HER and OER, respectively. By using the easy operation and classical bubble extraction method, we find that the Faraday efficiencies of the catalyst for HER and OER are 94.3% and 97.4%, respectively. Moreover, taking advantage of the micropores and mesopores in the yolk/shell structure, it exhibits enhanced stability and promoted diffusion kinetics. This work initiates an effortless approach to the synthesis of the highly efficient yolk/shell carbon-based OWS electrocatalyst. [ABSTRACT FROM AUTHOR]

The architecture and sedimentary characteristics of deep water deposition can reflect influences of sea-level change on depositional processes on the shelf edge, slope, and basin floor. Outcrops of the northern slope and basin floor of the Delaware Basin in west Texas are progressively exposed due to canyon incision and road cutting. The outcrops in the Delaware Basin were measured to characterize gravity flow deposits in deep water of the basin. Subsurface data from the East Ford and Red Tank fields in the central and northeastern Delaware Basin were used to study reservoir architectures and properties. Depositional models of deep water gravity flows at different stages of sea-level change were constructed on the basis of outcrop and subsurface data. In the falling-stage system tracts, sandy debris with collapses of reef carbonates are deposited on the slope, and high-density turbidites on the slope toe and basin floor. In the low-stand system tracts, deep water fans that consist of mixed sand/mud facies on the basin floor are comprised of high- to low-density turbidites. In the transgression and high-stand system tracts, channel-levee systems and elongate lobes of mud-rich calciturbidite deposits formed as a result of sea level rise and scarcity of sandy sediment supply. For the reservoir architecture, the fan-like debris and high-density turbidites show high net-to-gross ratio of 62 %, which indicates the sandiest reservoirs for hydrocarbon accumulation. Lobe-like deep water fans with net-to-gross ratio of 57 % facilitate the formation of high quality sandy reservoirs. The channel-levee systems with muddy calciturbidites have low net-to-gross ratio of 30 %. [ABSTRACT FROM AUTHOR]

Signal space method for time-domain characterization of short-pulse networks and antennas is presented and described. The short-duration pulses, which are usually recognized as energy signals, belong to the signal space L^2 (\Re) . By means of the signal space analysis, the Euclid distance on L^2 (\Re) is related to fidelity and amplitude ratio, and thus can be used for comprehensively characterizing short-duration pulse waveform distortion and amplitude variation, resulting in an overall description of networks and antennas. Three numerical examples, microstrip transmission line, microstrip pulse power divider, and antipodal Vivaldi antenna, are given to demonstrate the usage and significance of this method for characterization of networks and antennas. [ABSTRACT FROM PUBLISHER]

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]

The transport behaviors of nanomaterials, in especial multifunctional nanohybrids have not been well disclosed until now. In this study, environmentally relevant conditions, including cation types, ionic strength and pH, were selected to investigate the transport and retention of graphene oxide-hematite (GO-Fe 2 O 3) nanohybrids and a photoaged product in saturated sandy columns. Results show that more hybridization of hematite led to decreased negative surface charge, while increased particle size and hydrophobicity of the nanohybrids, which depressed their transport according to extented Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory. However, the inhibitory transport of photoaged nanohybrids was attributed to their distinct surface roughness caused by relatively high hybridization and photoirradiation. Notably the restrained transport was alleviated in the CaCl 2 saturated media, since the less surface O-functional groups of the corresponding nanohybrids reduced the cation bridging effect caused by Ca2+. Similarly, increasing pH promoted the transport of the nanohybrids in NaCl saturated media, particularly for the nanohybrids that contained rich O-functional groups, but exerted inconspicuous effect on mobility of the nanohybrids in CaCl 2 saturated media. These observations highlight that both XDLVO interactions and surface roughness may work together to impact the transport and fate of the burgeoning, versatile nanohybrids in the environment. [Display omitted] • Nanohybrids mobility decreased in the order of NH-Low > NH-High > rNH-High. • Hybridization led to less negative charge, larger particle size and hydrophobicity of the nanohybrids. • Irradiation-induced surface roughness aggravated the inhibitory transport of rNH-High. • Depressed transport of low O-functionalized NH-High and rNH-High was alleviated in CaCl 2. • Higher pH facilitated transport of nanohybrids in NaCl, but not in CaCl 2 electrolytes. [ABSTRACT FROM AUTHOR]

A tunable liquid crystal phase shifter based on opposed coplanar waveguide (OCPW) with excellent phase shift capability per wavelength is proposed. The proposed OCPW not only has good transmission characteristics and a quasi-TEM operating mode similar to the CPW, but also avoids the metalized via and complicated bias circuit in designing the phase shifter. Consequently, the phase shifter is easy to fabricate and miniaturize. The main structure of the phase shifter includes two functional components. One is the transition section, in which the flaring grounds and gradient stubs are utilized to realize the impedance and wave-number matching to the OCPW phase shift part; the other is a tunable phase shift section, which is composed of the OCPW centerline and ground with staggered periodic stubs stretching out. To realize tunable phase shifting by applying different DC bias voltages, a DC bias network capable of blocking RF signal is elaborately designed. An equivalent circuit model of the phase shift part is established and represented using the ABCD matrix, so that the relation between the related parameters and the phase shift per wavelength can be easily obtained to guide the design. The measurement results demonstrate that the proposed phase shifter achieves a total of 300° phase shifting, as high as 289°/ λ 0 phase shift per wavelength, and a good figure-of-merit of 59°/dB at 14.5 GHz. The phase shifter features the reflection coefficient less than âˆ'10 dB and the transmission coefficient bigger than âˆ'6 dB from 9.3 to 15 GHz. [ABSTRACT FROM AUTHOR]

Photocatalytic technology, which is regarded as a green route to transform solar energy into chemical fuels, plays an important role in the fields of energy and environmental protection. An emerging S-scheme heterojunction with the tightly coupled interface, whose photocatalytic efficiency exceeds those of conventional type II and Z-scheme photocatalysts, has received much attention due to its rapid charge carrier separation and strong redox capacity. This review provides a systematic description of S-scheme heterojunction in the photocatalysis, including its development, reaction mechanisms, preparation, and characterization methods. In addition, S-scheme photocatalysts for CO2 reduction are described in detail by categorizing them as 0D/1D, 0D/2D, 0D/3D, 2D/2D, and 2D/3D. Finally, some defects of S-scheme heterojunctions are pointed out, and the future development of S-scheme heterojunctions is proposed. [ABSTRACT FROM AUTHOR]

A measurement method of an active element antenna pattern in a hybrid antenna array with heterodyne architecture under a real environment is proposed and applied to the design of an ultralow sidelobe level scanning array. To avoid the phase uncertainty caused by the local oscillator signal in the heterodyne architecture, a phase‐normalized active element pattern (PNAEP) is used to characterize the element antenna patterns of both amplitude and phase. The PNAEP has almost taken account of all the practical factors of an array, such as mutual couplings, various types of element antennas, unequal spacing, or diverse environmental effects. The PNAEP is measured with a 16‐element scanning receiving array with a heterodyne architecture to validate the feasibility of the PNAEP. Based on the PNAEP, the scanning array achieve an ultralow sidelobe level of −33 dB. Applying to various receiving array architectures the PNAEP method is a feasible and universal tool for array synthesis and optimization under real environments. [ABSTRACT FROM AUTHOR]

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]

• The initial flux decline is mainly caused by membrane fouling. • Retentate concentration has a most powerful effect for flux decline when it rises to a certain level. • Although charge prevented the formation of suspended particles, accelerated flux decline occurred. • Membrane surface contamination is a more critical factor relative to internal duct (pore) contamination for flux decline. Ultrafiltration (UF) is an effective approach for the separation and purification of organic components dissolved in lignocellulosic pre-hydrolysis liquor (PHL). However, flux decline has been a problem that restricts UF industrial applications. Here, the main impact factors for flux decline on UF processing of PHL are examined. Flux decline curves for four UF membranes having different molecular weight cut-offs (MWCOs) indicated that the largest MWCO UF membrane had a faster flux decline rate because of its better ability to concentrate PHL. Using a 10-kDa UF membrane, the normal UF procedure was modified three different ways to study the independent factors affecting flux, including retentate concentration, charge density, and membrane fouling. The results indicated that membrane fouling was a main impact factor causing flux decline in the early stages of UF, and then charge and concentration effects gradually intervened. Relative to the latter factors, membrane fouling displayed a more regular behavior, with a good linear relationship between flux and operating time. Micro-computed tomography, scanning electron microscopy, and atomic force microscopy were used to characterize fouled membranes. It was revealed that surface contamination plays a more dominant role in flux decline than does internal contamination. [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]

The article presents a study which aims to determine the Cretaceous shallow- water delta in the Songliao Basin, China. The study suggests that the shallow-water deltas were developed commonly in lake basins under a comparatively stable tectonic setting, shallow water depth, gentle slope having low subsidence rate, a frequently fluctuating lake level, open lake basin characteristics and sufficient sediment supply.

Based on a new trade accounting method—the trade in value-added accounting method—this paper constructs the international manufacturing trade in value-added networks and preferential trade agreement (PTA) networks and uses the complex network analysis method to explore the relations between PTA and international manufacturing trade in value-added from the perspective of the global value chain. The results are as follows: (1) Over the years, the international manufacturing trade in value-added networks and PTA networks has shown a significant clustering effect, and the size of networks has grown rapidly. (2) The TEX, DVA and FVA networks of the international manufacturing value added trade over the years can be divided into two societies in the Asia-Pacific region and the European region. This division just reflects the different modes of division of labor in the manufacturing value chain of the two major economic regions in the world. (3) QAP analysis shows that the influencing factors of the traditional gravity model can still explain the manufacturing trade network and its value-added trade network, while the influence of economic globalization, the enlargement of the EU and the internationalization strategy of enterprises, the PTA network and manufacturing value-added the relationship between trade networks changed from positive to negative in 2004. [ABSTRACT FROM AUTHOR]

Liaodong Bay Depression is a strike‐slip basin with complex tectonic movement that lead the source‐to‐sink (S2S) systems evolution vary greatly in temporal and spatial characteristics. This study explored the sedimentary characteristics, dispersal patterns, and pathway formation in Liaodong Bay Depression, as well as their controlling factors. We selected more than 10 pathways with north‐west and north‐east directions in Liaoxi Sag in the western part of Liaodong Bay Depression, a typical strike‐slip bet controlled graben, to investigate their S2S system distribution. By combining seismic data, we divided the strike‐slip fault bends into three stress setting parts, namely, a central restraining bend, which is the fault translation part, and two releasing bends in the southern and northern of fault terminals. As the heavy mineral assemblage and clay content in the west side of Liaoxi Sag differs from that in the east side, we put forward an S2S index to show the sediment transport distance according to the data we have obtained. Using this index, we recovered the dispersal pattern and pathway development and speculated on the sedimentary provenance. In the restraining bend, we recognized that the pathways mainly show a symmetrical "V" or "W" shape with unclear erosion boundaries and were dominated by filling processes. Considering the heavy mineral assemblage data, we also found that the sediment provenance area decreased and the sediment provided direction transferred from the two‐side provenance to one. Combining the fast sedimentary rate calculated with clay content data, the S2S systems in this area were steep–wide–deep systems and a wide and shallow system. In the releasing bend, the pathways show an asymmetrical "V" or "W" shape and a clear erosional boundary. As shown by the heavy mineral assemblage data, the sediments from these areas mainly have a west side provenance and were deposited in the proximal area. Thus, the S2S system in this area is a kind of steep–deep system. Then, the investigation by integrated of tectonic movement and S2S geomorphic statistical parameters revealed that the elevation height of the S2S is a key factor in control pattern development. The various evolution patterns within the two different stress settings provide insights into the formation process of the S2S developed in a strike‐slip tectonic belt. [ABSTRACT FROM AUTHOR]

The fluorescence properties were first probed for wood prehydrolysis liquor (PHL) in the present study. Besides fluorescence concentration quenching and pH effects, the excitation wavelength-dependent photoluminescence properties were also observed at excitation from 360 to 430 nm. In order to explore the inducement of visible fluorescence, the fluorescence analysis was performed for acid-soluble lignin; X-ray diffraction and Raman spectroscopy were performed for the PHL solids and revealed that graphitic carbon in the form of carbon nanodots (CNDs) exists in lignocellulosic PHL. Transmission electron microscopy and atomic force microscopic analyses further characterized the morphology of the graphitic carbon. These CNDs have an average diameter of 5.04 ± 0.89 nm and two forms of lattice spacing of 0.23 nm and 0.34 nm; the average height is 1.73 ± 0.71 nm. The discovery of the fluorescence and CNDs in lignocellulosic PHL will greatly widen its promising applications. [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]

Three-dimensional carbon foam (CF) has been widely employed as a conductive framework for preparing self-supporting supercapacitor electrodes. Herein, based on the spin-drying mechanism of washing machine, a spin-coating method is developed to prepare carbon foam@graphene oxide (CF@GO) composites, in which a special centrifugation tube containing a macroporous shelf is used to separate the foam block and residual GO suspension during centrifugation. The GO fractions in CF@GO composites are controlled easily by tuning the spin speeds. As freestanding electrodes in two-electrode supercapacitors, the CF@GO-4500 (4500 rpm, 1.2 wt% GO) and CF@RGO-1000 electrodes (1000 rpm, 3.2 wt% GO) exhibit the specific capacitances of 159 Fg−1 (258 mF cm−2) and 180 Fg−1 (297 mF cm−2) at 0.5 Ag−1, respectively, which are much higher than those of CF and CF@GO-4 or CF@RGO-4 sample (15.3 wt% GO) prepared by a conventional soaking-freeze-drying method. The results show that a few GO/RGO sheets loading in CF framework exhibit an enhanced electrochemical performance in supercapacitor, rather than filling much GO/RGO. [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]

The stability and H ∞ performance analysis of a class of impulsive differential systems are addressed by using a two-point boundary value problem method. For convenience of computation, a sufficient and necessary condition for the existence of a solution to the two-point boundary value problem is expressed using a set of linear matrix inequalities. As an application example, we apply the suggested method to deal with the sampled-data H ∞ filtering problem. A numerical example of a mass–spring system is used to verify the effectiveness of the theoretical result. [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]

This paper proposes a novel filtering strategy characterized by an impulsive differential system. It provides an alternative solution to the problem of $$L_2-L_\infty $$ filtering for two kinds of network-based linear time-invariant systems. The presented method highlights two features, 'plug and play' and 'always feasible,' because it is simple and does not need to solve any complex constrained optimization problems. For measurable and unmeasurable system states, two different filter frameworks are presented, respectively. The proposed filtering strategy could guarantee the asymptotic stability of the filtering error system, while ensuring an $$L_2-L_\infty $$ performance. At the same time, the relationship between the $$L_2-L_\infty $$ disturbance attenuation level bound $$\gamma $$ and the maximum time-delay upper limit $$\tau _\mathrm{m}$$ is given. Finally, three illustrative examples are given to demonstrate the effectiveness of the proposed approach. [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 West Bogda Mountains separate the two largest petroliferous sedimentary basins in Northwest (NW) China and may record the evolution history of the Central Asian Orogenic Belt (CAOB). The timing of the initial uplift of the West Bogda Mountains is debated, which may provide the robust constraint on the CAOB evolution. Here we present an integrated study of sedimentology, geochemistry, and detrital zircon geochronology to constrain the timing of the initial uplift of the West Bogda Mountains. The late Lower Permian Lucaogou Formation in the West Bogda Mountains is dominated by organic-rich laminated shale, gravity flow deposits and dolomite without shallow-water sedimentary structures, suggesting a deep-water lacustrine depositional environment. The Middle Permian Quanzijie Formation is mainly composed of poorly sorted and sub-rounded conglomerate, which indicates that the depositional environment changed to an alluvial fan. The depositional environment changed to a meandering river system in the early Upper Permian Wutonggou Formation, with evidence from the widely developed cross-bedding in its sandstone and the typical 'dual structure'. The compositions of immobile elements and detrital zircon U-Pb geochronology reveal changes in sediment sources from the early to late Permian. The sediments of the late Lower Permian Lucaogou Formation were mainly sourced from the North Tianshan, while the sediments in the Middle Permian were mostly locally derived. Combining these evidences, we infer that the initial uplift of the West Bogda Mountains likely occurred in the period from the late Lower to Middle Permian (~289.8 Ma to ~265.7 Ma), and was probably caused by the intracontinental collision between Junggar Block in the north and the Tarim Block in the south. [ABSTRACT FROM AUTHOR]

A spoof surface plasmon polariton (SSPP) antenna with dual-band endfire gain and small frequency ratio (FR) is presented. It uses an asymmetric structure to support two independent surface waves with different nonlinear phase constants. Due to the different phases of the superposed $E$ -field at the terminal of the proposed structure, dual-band endfire gains and endfire radiation null are achieved. The odd- and even-mode feedings, providing additional phase differences, are also investigated. Three prototypes, with FRs of 1.06, 1.11, and 1.5, are designed, simulated, and measured, respectively. All results validate the mechanism and demonstrate that the FR of the proposed antenna can be achieved easily in the range of 1.06–1.5 by choosing different unit cells and feeding modes. Moreover, the measured endfire out-of-band gain suppression, over 17 dB, presents a good directional interference inhibition. This small-FR endfire antenna shows a broad prospect for band coverage and directional noise inhibition with very close operating frequencies. [ABSTRACT FROM AUTHOR]

Electrolysis of seawater is a promising approach to address freshwater scarcity and indirectly mitigate the energy crisis. In this context, the oxygen evolution reaction (OER) plays a crucial role as one of the half−reactions in water electrolysis. However, the development of cost−effective non−precious metal catalysts for OER remains a challenging issue. In this study, we present a facile method for synthesizing Prussian blue sulfides supported on nickel foam (NF) at ambient temperature. The resulting S−FeNi@NF catalyst demonstrates remarkable electrocatalytic performance with an overpotential of only 330 mV at a current density of 100 mA cm⁻² in simulated seawater. Notably, the catalyst exhibits excellent corrosion resistance and electrochemical stability, maintaining its effectiveness for over 120 h following vulcanization. Furthermore, we assessed the catalysts for their resistance to chloride ion corrosion in natural seawater and observed no significant signs of etching for more than 30 days. This outstanding stability of the S−FeNi@NF material can be attributed to its dual protective mechanisms against chloride ions, which encompass both corrosion resistance and the repulsion of chloride ions during electrochemical processes. Our findings offer a fresh perspective on catalyst design, particularly in the context of shielding against chloride−induced degradation in direct seawater electrolysis. • The negatively charged surface of the vulcanised catalyst effectively resists chloride etching. • No visible structural damage after 30 days of immersion in natural seawater. • In situ growth of PBA materials on NF effectively enhances conductivity and facilitates the four-electron transfer process. • The self-supporting electrocatalysts derived from PBA exhibit dual resistance to the effects of chloride ions. [ABSTRACT FROM AUTHOR]

The northwestern South China Sea (NW-SCS) presents a spatial-temporal evolution of its source-to-sink (S2S) system, that recorded the movement of the Indochina block and the collision between the Indian and Eurasian plates. However, complex tectonic movements and topographic evolution have led to controversial studies about the spatial-temporal distribution of allogenic materials and autogenic sediments. In this study, we integrated a number of multiscale data to review the S2S system evolution of the northwestern area of the South China Sea from the Eocene to the Miocene. The series include the initial synrift, postrift and thermal subsidence stages. First, we identified the major sediment pathways using seismic profile interpretation. We reconstructed the sediment distribution and lithofacies association within the dispersal sink area based on seismic data, core samples and grain-size analysis. We quantitatively studied the sediment flux and catchment area based on mass balance calculation modeling. Following this, we acquired rare-earth element (REE) data and zircon U–Pb age data from the bedrocks of the continental blocks and the South China Sea Cenozoic basement and rivers in the NW-SCS area to restore the provenance area and evaluate the migration distance by inspecting the heavy mineral assemblages. According to the above studies, three phases of S2S dynamics were identified. 1) The initial rifting stage occurred during the Eocene, and active rifting in the South China Sea induced a major topographic change. A large amount of autogenic slump sediments and a smaller amount of paleo-Red River sediments were injected into the Beibu Gulf Basin (BBGB) and the Yinggehai-Song Hong Basin (YGHB). 2) The postrift stage occurred during the Oligocene. Regional uplift and tectonic inversion probably linked to the clockwise rotation of the Indochina Block, broke the connection between the Beibu Gulf Basin and the Red River catchments. The paleo-Qin River and the paleo-Lian (Nanliu) River brought a large amount of clastic material into the Beibu Gulf Basin from the Cathaysia Block. 3) The thermal subsidence stage occurred during the Miocene: the eastward topographic tilt was enhanced, and the drainage basin entered postrift stage. The development of the Paleo-Red River and its branches, the Lam River and the Ma River, brought distal sediment into the YGHB, while the rivers in the west Cathaysia Block transported sediment into the BBGB. Statistical analysis of the S2S system parameters suggests that the average terrain altitude played a dominant role in determining the S2S system volume during the Eocene, while the dominant role transferred to the sediment supply during the Oligocene and Miocene. • Reconstructs the Source to sink system within NW-SCS from the Eocene to the Miocene. • Reveal the drainage evolution of basins in NW-SCS with multiple dates. • Put out the impact factors to the Source-to-Sink system developed during the rifting process. [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]

An endfire frequency scanning tapered slot antenna (FSTSA) is proposed and investigated. The proposed FSTSA is a two-conductor structure with a gradient slots array etched only on one of two inner edges in the FSTAS. The asymmetrical inner edges enable the antenna to excite two modes with different phase constants simultaneously along the two inner edges. Due to dispersion characteristics of spoof surface plasmon polaritons (SSPPs), the phase difference between the EM waves along the two conductors changes versus frequencies, which enables the main lobe of the FSTSA to scan through the endfire direction. An analysis model is conceived to provide insights into the design, which accurately predicts main lobe directions and initial values of the proposed antenna. The proposed antenna is fabricated, and the measured results show that the main lobe of the antenna scans from −15° to 14° (endfire direction at 0°) from 6.60 to 7.70 GHz, with the scanning rate of 26.4°/GHz. This antenna could be suitable for radar, plane integrated communication system, and certain other beam-scanning applications. [ABSTRACT FROM AUTHOR]

Although volcanism is an important process in the evolution of rift basins, current tectono‐sedimentary models largely neglect its impact on sediment supply, transport pathways, and depositional systems. In this paper, we integrate core, well logs, and 3D seismic data from the Palaeogene‐Neogene Shaleitian (SLT) uplift and surrounding sub‐basins, Bohai Bay Basin, China, to investigate the sedimentology and geomorphology of a volcanic rift basin. Results of this study show that the spatial distribution of extrusive centres was strongly controlled by basement‐involved intra‐basin normal faults. During the early part of the syn‐rift stage, the SLT uplift supplied sediments to transverse fan deltas and braided‐river deltas that fringed the adjacent syn‐rift depocentres. Volcanic deposits mainly occurred as relatively thin lava flow and pyroclastic facies that partially filled fault‐controlled topographic lows, reducing topographic rugosity, and enhanced breaching of basement highs between syn‐rift depocentres. Integration of drainage to the syn‐rift depocentres and development of through‐flowing axial depositional systems was enhanced. During the later part of syn‐rift and in early post‐rift stages, the SLT uplift was progressively inundated, reducing sediment supply to the fringing transverse depositional systems. In contrast, axial braided‐river deltas became the main depositional systems, sourced by large hinterland drainage from the Yanshan fold‐belt to the northwest. Volcanism in the late syn‐rift and early post‐rift occurs as thick lava flow and pyroclastic facies that infill rift topographic lows and locally blocked axial fluvial systems creating isolated lakes. Within hanging wall depocentres, volcanic topographic highs split and diverted axial fluvial and deltaic systems. Furthermore, volcanism supplied large volumes of volcanic sediment to the rift resulting in increased sedimentation rates, and the development of unstable subaerial and subaqueous slopes and deposits, increasing the occurrence of landslides. Based on the observations of this study we update tectono‐sedimentary models for rift basins to include volcanism. [ABSTRACT FROM AUTHOR]