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A model of the channel and catchment components of sediment runoff has been developed. The model makes it possible to estimate the intensity of redistribution of river and bottom sediment in the riverbed, the size distribution of deposited or migrating particles, the mass of particles in the riverbed and catchment components of sediment load, as well as the contribution of the catchment component. The model is based on the assessment of the transport potential of the watercourse and the dynamics of the curves of the granulometric composition of bottom sediment, and products of soil and channel erosion. This approach is focused on the steady flow movement without additional sources of tributary sediment, intensive abrasion of river banks, and products of anthropogenic load. Calculations based on the model applied to the Narva River showed that the contribution of the catchment component to the sediment flow of this watercourse after intense rain is approximately 98%. The obtained results are well confirmed by the weak dynamics of channel deformations in the studied part of the watercourse. [ABSTRACT FROM AUTHOR]

The hybrid friction stir channeling (HC) is a recent manufacturing technique, reinforcing the broad range of solutions provided by the technological domain of solid-state friction stir-based welding and processing. HC enables the simultaneous welding of multiple components and the sub-surface channeling within the desired region at the stir zone. HC provides new demanding solutions having free path sub-surface channeling and welding for multi-material components with optimized physical and chemical performances. In the present investigation, a multi-material system consisting of 8 mm thick Al-Mg alloy (AA5083) and 3 mm thick oxygen free copper (Cu-OF) was processed by HC. A specially designed tool consists of the probe's body features that steer materials extraction and the probe's tip features that generate materials mixing was applied to produce sub-surface channel at AA5083, along with its simultaneous welding to Cu-OF material. Visual examination of the AA5083′s surface processed by the shoulder, cross-sectional dimensioning, optical 3D scanning of the internal surfaces of the channel, optical and scanning electron microscopy, energy dispersive X-ray spectroscopy, electron backscatter diffraction and micro-hardness measurements were applied to investigate the results. The successful application of HC to manufacture multi-material Al-Cu component is demonstrated. A large sub-surface quasi rectangular channel with 9.6 mm in width per 3.3 mm in height was produced in the AA5083 rib along with defect free welding to thin Cu-OF plate at just below the channel region multi-material. The resulted sub-surface channel was consisted of unique wall surface features, with non-uniform and non-oriented surface roughness, suitable to activate turbulent fluid flow. The microhardness field depicts a higher-strength domain of the stirred material, at the ceiling of the sub-surface channel in comparison with the base materials. The welding zone comprises a metal matrix composite structure with Al-Cu inter-mixing and a mechanical hooking from Cu into the Al matrix. The metallurgical features of the weld stirred zone were analyzed, with an interpretation of Al-Cu phases, and solid solution of Al and Cu in each other. In this zone, Cu-rich lamellae regions are dispersed within the Al-matrix, presenting thin layers of discontinuous intermetallic compounds. The effective potential of manufacturing multi-material component for applicability in thermal management system is demonstrated. [Display omitted] • Multimaterial Al-Cu Component by Hybrid friction stir Channeling (HC) is presented for the first time. • Sub-superficial channel produced on Al rib along with defect free welding to thin Cu plate in a single manufacturing action. • Unique features of channel's surfaces along with excellent metallurgical bonding of Al-Cu multimaterials is obtained by HC. [ABSTRACT FROM AUTHOR]

For the drag and heat flux reduction of hypersonic blunt body, a novel combinational spike-aerodisk and channel concept has been proposed. The high pressure air behind the bow shock flows into the channel at the head of the aerodisk, and then sprays out through the lateral jet in the middle of the spike. The Reynolds-averaged Navier-Stokes (RANS) equations coupled with the shear stress transport (SST) k - ω turbulence model have been employed to simulate the flow field. The numerical results reveal that compared with the spike-aerodisk, with the application of the channel, the lateral jet pushes the separated shock wave away from the spike. The range of the recirculation zone between the shear layer and the spike is increased, and the intensity of the reattached shock wave is significantly weakened, so the drag and heat flux reduction properties of the combinational configuration are significantly improved. The influences of the channel convergent half angle and lateral jet location on the flow field, drag and heat flux reduction properties are investigated thoroughly. When the channel convergent half angle is appropriate and the location of the lateral jet is close to the middle of the spike, the drag and heat flux reduction effect becomes better. Besides, with the increase of the Mach number and the decrease of the flying height, the drag and heat flux reduction performance become more significant. In the research range, the combinational configuration in which the convergent half angle is 60° and the lateral jet is located in the middle of the spike has a better overall effect of drag and heat flux reduction, and the effect reaches the best when the Mach number is 6 and the flying height is 20 km. Compared with the spike-aerodisk, the total drag coefficient of the configuration is reduced by 12.95%, and the peak value of Stanton number along the blunt body surface is reduced by 35.19%. • A novel combinational spike-aerodisk and channel concept was numerically investigated. • The combinational concept has better performance in both drag and heat flux reduction. • Effects of channel convergent half angle and lateral jet location on drag and heat flux reduction were studied. • Variation laws of drag and heat flux reduction under different Mach numbers and flight altitudes were analyzed. [ABSTRACT FROM AUTHOR]

• A new lamilloy structure equipped with staggered internal minichannels is put forward to achieve an effective cooling. • The lamilloy structure consists of three cooling effects: the impingement cooling, forced convective heat transfer and the film cooling. • The effect on the cooling performance of mass flow ratio and temperature ratio are investigated and compared. The efficiency improvement of the advanced high-power heavy-duty gas turbine will certainly make the design of the combustor develop in the direction of high temperature rise and high heat capacity. Lamilloy cooling is considered the promising cooling structure that can replace the currently commonly used film cooling. This paper proposes a novel long-channel lamilloy cooling structure equipped with internal channels and pin-fins used in combustor flame cylinders, and the cooling and flow characteristics of the proposed structure are studied by combining experiment and simulation. An experimental system is established to explore the cooling characteristic of the proposed structure, and the effect on the cooling characteristic of mass flux ratio (1.07 %∼2.35 %) and temperature ratio (0.5∼0.7) are studied and compared. The cooling effectiveness is found to be increased by 39.62 % when the mass flux ratio increases from 1.07 % to 2.35 % while keeping the temperature ratio at 0.5, and increased by 28.14 % when the temperature ratio increases from 0.5 to 0.7 while keeping the mass flux ratio at 1.07 %. The numerical results show that when T * =0.6, m f * increases from 1.07 % to 2.35 %, the η a increases from 0.469 to 0.628, correspondingly increased by 33.9 %. When m f * =1.93 %, T * increases from 0.5 to 0.7, the η a increases from 0.567 to 0.602, correspondingly increased by 6.27 %, the corresponding increment is weak. The flow field structure shows that strong vortex structures are formed around the pin-fins, and the secondary flow is induced when the coolant flows through the region of the pin-fins, which will enhance the local heat transfer effect. Moreover, the coolant ejecting from the film hole acts as a "baffle", blocking the direct contact between the mainstream and the LLC, playing a similar role to the film cooling. The long-channel lamilloy cooling structure proposed is an effective measure to replace the film cooling, and the research herein provides some reference for designing the combustor flame cylinder cooling structure. [ABSTRACT FROM AUTHOR]

• The improved two-phase flow model in channel is proposed. • The contact angle hysteresis is incorporated into the model. • The effect of channel wettability on liquid water distribution is investigated. • The effect of liquid water in channel on fuel cell is comprehensively investigated. • The existence of liquid water in straight channel reduced the optimal inlet humidity. Water management in channel plays a crucial role in influencing the performance of proton exchange membrane fuel cell (PEMFC). However, the limited comprehensiveness of existing model has hindered the investigation of this phenomenon. To investigate the impact of liquid water transport in channel on overall water and gas transport, as well as the performance of PEMFC, this study modifies the existing model by incorporating factors such as the channel wall wetting properties. Specifically, contact angle hysteresis is incorporated into the model. Based on the modified model, this study investigates the impact of liquid water in channel under various operational conditions and channel design schemes. The results demonstrate that the existence of liquid water in straight channel increases the liquid water saturation in gas diffusion layer while reducing the optimal inlet humidity and operating temperature. When relative humidity (RH) is around 0.5, the difference in the prediction results of the performannce of PEMFC is greatest when considering whether liquid water in channel is present or not. Channel wall with larger static contact angle and smaller hysteresis contact angle reduces liquid water volume fraction within channel, thereby enhancing oxygen transport while decreasing membrane water content. [ABSTRACT FROM AUTHOR]

Identification of geological features from seismic data such as faults, salt bodies, and channels, is essential for studies of the shallow Earth, natural disaster forecasting and evaluation, carbon capture and storage, hydrogen storage, geothermal energy development, and traditional resource exploration. However, manual seismic interpretation is distinctly subjective and labor-intensive. With the advent and rise of 3D surveys, the size of seismic data has increased dramatically, making purely manual interpretation impractical. Since 1989, a large number of machine learning-based methods for identifying geological features have been proposed to address these challenges. To date, these methods have not been reasonably synthesized. Motivated by a progressive increase in applications, this review presents an overview of advances in the utilization of machine learning to identify geological features from seismic data. First, we classify these methods from five different perspectives. Second, we provide a comprehensive overview of 241 publications related to seismic geological feature identification and offer a detailed analysis of the development of these methods categorized by geological feature type. Third, 20 field and 12 synthetic seismic datasets, which are publicly available and relevant to the identification of faults, salt bodies, channels, caves, and horizons, are cataloged. Fourth, we discuss the issue of false positive identification caused by the limited geological features in the training dataset. To address the problems of false positives and insufficient labeled training datasets, we propose a simulation framework for generating 3D synthetic seismic data and corresponding geological labels that include a rich variety of geological features. To the best of our knowledge, this is the synthetic seismic dataset that contains the richest geological features. Finally, we discuss in depth the current challenges and future opportunities to inspire further relevant research. • Conducted a comprehensive review of ML-based seismic subsurface feature identification from 1989 to 2023. • Synthesized publicly available datasets and open-source projects for fault, channel, salt body, cave, and horizon identification. • Released a large seismic dataset with fault labeling for benchmarking. • Discussed the impact of limited geological features in training data and proposed an improved workflow for generating 3D synthetic seismic data. • Provided an in-depth analysis of current challenges and future opportunities. [ABSTRACT FROM AUTHOR]

The pathogenesis of ventricular tachycardia (VT) in most patients with a prior myocardial scarring is reentry involving compartmentalized muscle fibers protected within the scar. Often the 12-lead ECG morphology of the VT itself is not available when treated with a defibrillator. Consequently, VT ablation takes on an interesting challenge of finding critical targets in sinus rhythm. High-density recordings are essential to evaluate a substrate based on whole electrogram voltage and activation delay, supplemented with substrate perturbation through alternate site pacing or introducing an extra stimulation. In this article, we discuss contemporary intracardiac electrogram targets for VT ablation, with explanation on each of their specific fundamental physiology. [ABSTRACT FROM AUTHOR]

[Display omitted] • Unidirectional freezing of agar gels creates an anisotropic porous network. • Pore cross-sectional area is larger with a slower freezing rate. • Compression response of unidirectionally-frozen gels depends on freezing rate. • Proton spin–spin relaxation & water mobility in the gels depend on pore dimensions. The controllable formation of anisotropic gel structures is presently sought for the development of foods with novel textures. Here, we used unidirectional freezing to generate agar gels consisting of a honeycomb-like porous network of elongated and aligned pores. A custom-built Peltier system allowed for control of the freezing front velocity throughout the agar gels. A higher freezing velocity (10 µm/s) led to smaller pore sizes compared to the slower freezing velocity tested (2 µm/s). Texture analysis highlighted the significantly higher Young's modulus in the gels when compressed in the axial vs. radial direction − a direct consequence of the unidirectional freezing. The proton spin–spin relaxation time revealed greater water mobility in the unidirectionally frozen gel with larger pores. This study serves as the basis for the development of anisotropic hydrocolloid gels with a tunable microstructure and texture. [ABSTRACT FROM AUTHOR]

• A three-energy equation model was utilized to analyze forced convective heat transfer in bi-disperse packed bed channels and circular tubes. • An exact solution was obtained for hydrodynamically and thermally fully developed Darcy flows in a bi-disperse packed bed channel under constant wall heat flux conditions. • Highly accurate approximate solutions based on an integral method were developed for plane and axisymmetric forced convective flows. • Nusselt numbers for conduits filled with a bi-disperse packed bed are much higher than those for conduits filled with a mono-disperse packed bed. • Employing fillers with comparatively larger diameters is advisable to mitigate excessive pressure drop. A three-energy equation model was utilized to analyze forced convective heat transfer in bi-disperse packed bed channels and circular tubes. The fluid phase energy equation was coupled and solved with two distinct heat conduction equations, accounting for both large and small particles. An exact solution was obtained for hydrodynamically and thermally fully developed Darcy flows in a bi-disperse packed bed channel under constant wall heat flux conditions. Additionally, highly accurate approximate solutions based on an integral method were developed for plane and axisymmetric forced convective flows, for which exact solutions are unavailable. The Nusselt numbers for conduits filled with a bi-disperse packed bed were found to be significantly higher than those for conduits filled with a mono-disperse packed bed. Since the Nusselt number remains insensitive to the filler diameter under fixed porosity conditions, employing fillers with comparatively larger diameters is advisable to mitigate excessive pressure drop. [ABSTRACT FROM AUTHOR]

With the development of deep learning, medical image segmentation in computer-aided diagnosis has become a research hotspot. Recently, UNet and its variants have become the most powerful medical image segmentation methods. However, these methods suffer from (1) insufficient sensing field and insufficient depth; (2) computational nonlinearity and redundancy of channel features; and (3) ignoring the interrelationships among feature channels. These problems lead to poor network segmentation performance and weak generalization ability. Therefore, first of all, we propose an effective replacement scheme of UNet base block, Double residual depthwise atrous convolution (DRDAC) block, to effectively improve the deficiency of receptive field and depth. Secondly, a new linear module, the Multi-scale frequency domain filter (MFDF), is designed to capture global information from the frequency domain. The high order multi-scale relationship is extracted by combining the depthwise atrous separable convolution with the frequency domain filter. Finally, a channel attention called Axial selection channel attention (ASCA) is redesigned to enhance the network's ability to model feature channel interrelationships. Further, we design a novel frequency domain medical image segmentation baseline method FDFUNet based on the above modules. We conduct extensive experiments on five publicly available medical image datasets and demonstrate that the present method has stronger segmentation performance as well as generalization ability compared to other state-of-the-art baseline methods. [ABSTRACT FROM AUTHOR]

High dielectric response and low leakage conduction are desired in polymer/ceramic composite dielectrics for capacitive energy storage. Rational structural design of hybrid ceramic filler can lead to a balance between high dielectric constant and insulation in composites. In this study, high dielectric constant and breakdown strength were achieved in fluoropolymer/mesoporous silica@CdTe nanocomposite films. Mesoporous silica nanoparticles (MSNs) were employed owing to their high insulation and complex electron-leakage channel. CdTe quantum dots combined with pore-canal inwalls of MSNs were employed because of their internal exciton polarization and MSNs/CdTe interface polarization. Compared with polymer/MSNs composites, polymer/MSNs@CdTe composites exhibited remarkably improved dielectric constant, slightly increased dielectric loss, and slightly reduced breakdown strength. High dielectric constant of ternary composites was ascribed to exciton orientation inside CdTe and interfacial dipole orientation between MSNs and CdTe. High breakdown strength was attributed to high insulation in MSNs and long-range electron transfer inside MSNs@CdTe. An optimal ternary composite with 12 wt% MSNs@CdTe showed a high dielectric constant of ~56, low dielectric loss of ~0.19 at 100 Hz, and high breakdown strength of ~308 MV m-1. The results of this study can provide insights for enabling large-scale fabrication of modern composite dielectrics based on mesoporous particles@semi-conductive quantum dots fillers. [Display omitted] [ABSTRACT FROM AUTHOR]

The widespread use of available skin friction relations in engineering and in turbulence research is ample justification to examine their validities and limitations of use. The Prandtl–von Kármán logarithmic friction law (Prandtl, 1932), for instance, is vitally important for decades for predicting wall skin friction. There have been, however, rising concerns regarding its accuracy due to the deficit of the flow similarity assumption adopted in the vicinity of the wall and in the core/outer region of the flow field. Hence, the wall skin friction could possibly be doubtful when predicted using the Prandtl–von Kármán relation, in particular at high Reynolds numbers compared with values obtained from direct measurements. We therefore briefly review the recent advances in the logarithmic friction relation based on the latest pipe, channel, and boundary layer wall friction data over a wide range of Reynolds numbers. Common similarities and differences among those flows, particularly in terms of the mean flow and the wall skin friction data are highlighted. Recent pipe friction relations (Mckeon et al., 2005) are compared with the Prandtl–von Kármán logarithmic friction law and verified with new accurate pipe friction data. A revisited logarithmic skin friction relation for plane-channel flows (Zanoun et al., 2009) is reported, predicting the wall friction with an accuracy of better than ± 1. 44 %. A modified logarithmic skin friction relation for external flows introduced by Nagib et al. (2007) is presented and discussed. We believe that having a concise review and summary of the often used friction relations in wall-bounded shear flows in a single article will be of interest to fluid mechanics readers. [ABSTRACT FROM AUTHOR]

Large wood exerts an influence on the topography and geomorphology of channels in areas of good vegetation development, and it is also an important component of riverine ecosystems. However, large wood may impact and damage buildings. The formation and failure of logjams can cause backwater rise, local scour, and the amplification of flow discharge, leading to more serious disasters. Therefore, quantifying the processes of large wood recruitment, entrainment, transport, deposition, accumulation and logjams failure is highly significant for the prevention of large wood hazards in channels. Based on existing research on large wood, this review provides a comprehensive analysis of large wood dynamics and hazards. First, the processes involved in large wood recruitment, entrainment, transport, and deposition are reviewed. Second, the results of large wood accumulation probability and the backwater rise, local scour, critical conditions of logjams failure and magnitude amplification of the flow discharge caused by large wood are analyzed comprehensively. Finally, large wood-related hazard mitigation measures are also introduced. Future research directions to improve the mitigation of hazards from large wood should concentrate on exploring quantification models for understanding how large wood impacts and accumulates on various built structures. • Larger wood transport and accumulation pose hazards to built structures. • Dimensionless method for comparative analysis of large wood dynamics • Field monitoring is highly applicable to the large wood-related hazard assessment. • Identifying the locations of logjams at the basin scale is essential. [ABSTRACT FROM AUTHOR]

and Mn-incorporated apatite-type phosphate, Ca 10 (PO 4) 6 Cu x Mn y (O,OH) 2 , was successfully synthesized by heating the hydroxyapatite under N 2 at 900 °C after Cu- and Mn-nitrate aqueous solution loading with x = 0–0.2 and y = 0–0.2 onto it. In Ca 10 (PO 4) 6 Cu 0·2 Mn 0·2 (O,OH) 2 , Cu occupies the apatite channel center site, and the Mn site shifts from the center. The deposition of Cu and Mn species was found to occur upon heating Cu 0·2 Mn 0.2 -Ca-HAp at 600–800 °C in air, accommodating the spinel-type complex metal oxide, (Cu, Mn) 3 O 4 formation from the apatite channel. In addition, the CuO deposition from the Ca 10 (PO 4) 6 Cu 0·2 (O,OH) 2 apatite was observed for samples heated at 600–800 °C, whereas Mn 3 O 4 was observed for the Ca 10 (PO 4) 6 Mn 0·2 (O,OH) 2 sample heated at 800 °C. These results suggest that the presence of Cu in the apatite channel facilitates the deposition of Mn species. [Display omitted] • Both Cu and Mn were successfully incorporated into hydroxyapatite. • Cu and Mn occupied different sites in the apatite lattice. • The spinel-type complex metal oxides, (Cu, Mn) 3 O 4 were deposited on the apatite by heat treatment under air. [ABSTRACT FROM AUTHOR]

Large eddy simulations of turbulent flow and passive scalar transport in a channel partially filled with an array of spherical particles, mimicking a layer of deposited material over a surface, are carried out to investigate the effect of turbulence mixing on the passive scalar transfer rate from the channel wall. It is observed that large turbulence structures generated at the permeable layer-fluid interface penetrate into the porous media and enhance the scalar transport from the channel wall. The small gap between the layer of particles and the wall also induces a channeling effect that implies turbulence mixing and high velocity near the wall resulting in an enhancement in scalar transport from the channel wall. The influence from the distance between the particles in one layer, particle diameter and the gap thickness on the passive scalar transport is also investigated. It is found that the highest Stanton number is derived for the largest distance between particles since this facilitates the motion of the large turbulent structures into the porous layer. Such motions will affect the scalar transport from the channel wall into the bulk. The channeling effect is observed to be the most important parameter when the particle diameter and the gap thickness are varied, and the highest Stanton number is achieved for the cases with the most effective channeling effect. Unlabelled Image • LES of turbulent flow and passive scalar transport is carried out in a channel. • The channel wall is covered with an array of particles mimicking porous layer. • Turbulence structures formed over permeable layer affect the scalar transport. • The channeling effect due to porous layer highly affects the scalar transport. [ABSTRACT FROM AUTHOR]

• The flow through a wall-flow filter has been described using a 3D CFD model. • New statistically validated models for the pressure drop are developed. • The friction factor inside the filter channels is not constant. • The friction factor is different from that for pipes with non-porous walls. • Kinetic energy and momentum flux correction factors are presented. This paper presents a detailed study of the fluid dynamics inside a wall-flow filter and proposes a new pressure drop model. A 3D channel scale computational model of a filter validated with experiments is used. A detailed description of the pressure drop for flow entering, passing through and leaving the filter is provided. The computational grid is extensively analyzed, and it is found that wall-flow is very insensitive to the grid quality, opposite to the local pressure, which is very sensitive. Several flow rates and wall permeability are analyzed. The most critical assumptions commonly found in current models are discussed based on the results. It is found that the friction factor of the channels is non-constant, it is different for the inlet and the outlet channels, and both differ from that for pipes with non-porous walls. A new criterion to determine the flow inside the filter as fully developed is also presented. The wall-flow along the perimeter of a cross-section is observed to be variable, consistently for many flow rates and wall permeability. The results are also used to develop a comprehensive, physically based, pressure drop model that shows very good agreement with experimental data. It is found that the propagation error when using the model to back-calculate physical parameters is strongly sensitive to the experimental conditions; hence, guidelines to minimize it in further experiments are provided. [ABSTRACT FROM AUTHOR]

The radio determination satellite service (RDSS) is an advantageous and unique aspect of the BeiDou Navigation Satellite System (BDS) because other satellite navigation systems do not incorporate the RDSS. Due to the ageing of RDSS equipment, there is a long-term drift in various types of RDSS equipment time delays. There are some differences in the RDSS positioning accuracy with the change in the out-station beams, which seriously affects the positioning accuracy and service capability of the RDSS system. At present, the time delay calibration method involves sending the device to the equipment verification field to remeasure the time delay, which is cumbersome and time-consuming. The service performance and availability of the RDSS system have become greatly degraded. Therefore, a simple and efficient RDSS time delay calibration method has become an important topic for the global BeiDou system. In this study, the time delays of all channels, in-station beams, and out-station beams were obtained by the O-C method (O is the measured value and C is the theoretical value). The experiments were performed using BeiDou RDSS data in continuous 8-day tests involving five RDSS users. The results showed that the time delay accuracies of the RDSS channels, in-station beams, and out-station beams were 2.37 ns, 1.63 ns, and 2.39 ns, respectively. The positioning tests were performed based on the original and adjusted delays. The mean horizontal positioning accuracy of the five RDSS users improved from 19.71 to 4.14 m, with an average increase of 77%. The positioning accuracy achieved in this paper is much better than that of 20 m in the Beijing calibration area at present. [ABSTRACT FROM AUTHOR]

Inter-symbol interference (ISI) is prone to occur in the operation of communication system, which affects the quality of communication. Therefore, the suppression method of ISI in communication system based on mathematical chaos theory is studied to optimize the quality of communication transmission. Based on the analysis of the principle of ISI in communication system, it is known that multi-path delay can lead to ISI. The multi-path channel model of communication system is constructed, the multi-path component delay of the channel is calculated, and the inter-symbol interference is suppressed by setting a reasonable delay. The equalizer's weight vector of communication channel is optimized by using chaotic optimization algorithm, the optimized equalizer tap of communication channel is obtained, and the reasonable multi-path component delay of channel is calculated to effectively suppress ISI. The simulation results show that the suppression method of ISI based on mathematical chaos theory can effectively overcome the ISI of multi-path channel, improve the resolution of transmission signal and the quality of communication transmission. [ABSTRACT FROM AUTHOR]

This study developed a pore-connected PP-CA membrane by coating cellulose acetate onto a polypropylene filter. A new method was proposed to attach a CA/glycerin coating layer to a porous PP support without a separate binder. The pores of CA and PP were interconnected using a vacuum filtration device. By adding glycerin to the CA chains, the membrane region became more flexible due to glycerin plasticization. Water passed through the membrane under pressure differences, resulting in the formation of interconnected pores between cellulose acetate and polypropylene. The pore size and quantity could be adjusted by varying the molar ratio of glycerin. Fourier transform infrared spectroscopy revealed the interaction between CA and glycerin, while thermogravimetric analysis showed that the membrane's thermal stability increased by approximately 20 °C after vacuum filtration. This simple and cost-effective manufacturing process holds potential for mass-producing separators in the lithium-ion battery industry. • Thermal stable separator based on cellulose and polyolefins by vacuum assisted process • Interconnected channels through cellulose and polyolefin by pressure difference • Mass transport of specific solvents through medium of two polymers [ABSTRACT FROM AUTHOR]

Lithofacies of host sediments associated with gas hydrate reservoirs may have a significant influence on the formation of hydrates. The type of sediments and the depositional processes responsible for the gas hydrate-bearing sediments along the eastern margin of the India have been studied by integrating core data and logging-while-drilling downhole logs. Borehole data correlated with seismic data were used for the interpretation of geological process responsible for gas hydrate formation. The acquired seismic profiles were correlated with the downhole logs by identifying the shape of the well logs curves that indicate finning up and blocky patterns. Turbidite sands and debris flows were also identified from the log and core sediment studies. This study identified two prominent types of depositional systems: (1) turbidity currents and (2) debris flows were mainly responsible for the deposition of gas hydrate-bearing reservoirs in the study area. Based on these studies two well-developed gas hydrate systems have been identified in the Krishna-Godavari Basin and hydrates were determined to be distributed mostly in sand dominated facies. Fine-grained sand in the identified turbidite deposits were shown to be a good hydrate reservoir. The hydrate-bearing sediments in the central part of the Krishna-Godavari Basin (Area C in D6 block) consist of mostly debris flows, which is consistent with scattered gravel- and sand/silt-sized grains in channel-levee systems. • Based on integrated log, core and seismic studies, hydrates are found distributed in sand dominated facies during NGHP-02. • Turbidite sands and debris flows were identified from the log and core sediment studies. • The lithofacies in the Area E is sand-silt-clay sequences. • Debris flows are identified, in the sediments of Area C. • In Area B, very fine sand/silt sediments deposited by turbidity currents. [ABSTRACT FROM AUTHOR]

This article presents exact solution for pressure driven flow formation of electrically conducting fluid in a parallel plate channel formed by two horizontal parallel plates with electrokinetic effects and induced magnetic field. Using the Poisson–Boltzmann, Navier-Stokes equations and induction equation, the governing electric potential, momentum, induced magnetic field and energy equations for the present article are presented and transformed to their corresponding dimensionless form using suitable parameters. The governing dimensionless equations are solved exactly and graphical representation are presented. During the cause of graphical illustration, it is found that the role of electrokinetic effects and Hartmann number is to decrease the electric potential, fluid velocity, induced magnetic field and fluid temperature. A special case is found and discussed when the value of Hartmann number equals the Debye-Hückel parameter. It is interesting to note that heat transfer is independent on governing parameters for large value of Debye-Hückel parameter. [ABSTRACT FROM AUTHOR]

Controlling the electrical property of single-walled carbon nanotube (SWCNT)-based devices is challenging because the SWCNTs have semiconducting or metallic characteristics that are dependent on their chirality. In this report, we demonstrate that a monolayer SWCNT bundle Langmuir-Blodgett (LB) film exhibits anisotropic electrical properties owing to the aligned assembly, and therefore the devices fabricated from this film demonstrate different gating effects reliant on the channel dimensions. Control of the channel dimension significantly affects the modulation of semiconducting behavior of the SWCNT-based devices. The shrinkage of the channel dimension induces a drastic decrease in the metallic pathway, which in turn enhances the semiconducting behavior of the device. • Well aligned SWCNT film-based devices were prepared by Langmuir-Blodgett (LB) technique. • Channel dimension of SWCNT LB film affects the semiconducting property of the devices. • The shrinkage of the channel dimension enhances the semiconducting behavior of the device. [ABSTRACT FROM AUTHOR]

• An artificial neural network (ANN) was applied for computing the development length of laminar magnetohydrodynamics (MHD) flow in the entrance region of a channel. • The finite volume method (FVM) was conducted to collect the input data for ANN. • A feed-forward back-propagation neural network contained one hidden layer including was trained and developed to predict the development length. • Comparison of the ANN with FVM and proposed correlation results revealed that ANN can be employed for modeling the developing MHD channel flow and computing of the development length. In the present study, an artificial neural network (ANN) was applied for computing the development length of laminar magnetohydrodynamics (MHD) flow in the entrance region of a channel. The finite volume method (FVM) was conducted to investigate the laminar MHD channel entrance flow. The investigation was applied for Reynolds number (Re) ranging from 600 to 1200 while Hartmann number (Ha) ranging from 4 to 14. 60 datasets were obtained from numerical solution and then, a feed-forward back-propagation neural network contained one hidden layer including was trained and developed to predict the development length. Using ANN, a correlation for predicting the MHD channel flow development length was proposed. Comparison of the ANN with FVM and proposed correlation results revealed that ANN can be employed for modeling the developing MHD channel flow and prediction of the development length. It was found that with the increase of Ha , the velocity profile gets flatten and consequently, the development length becomes shorter. Moreover, by augmentation of Re, the development length increases. [ABSTRACT FROM AUTHOR]

Human activities, involving construction such as large-scale bridge projects in tidal estuaries, can lead to undesirable and severe morphodynamic responses, such as excessive siltation in the harbors and channels. Lingdingyang Bay of the Pearl River Estuary (LBPRE) is a typical bay with unique geomorphological features that might cause complex changes in hydrodynamic features and sediment movement. The LBPRE includes a number of harbors and channels, including Nansha Harbor of Guangzhou Port and the western harbors of Shenzhen Port, which are two hub ports in South China, and their corresponding and important Lingding and Tonggu channels. Designed to cross over the LBPRE to connect Hong Kong, Zhuhai, and Macao, the proposal of the Hong Kong–Zhuhai–Macao Bridge (HZMB) is a representative of the most complicated and the longest sea-crossing transportation project in the world, which consists of several segments of bridge, a tunnel, and two man-made islands. Therefore, it is of extreme significance to demonstrate the effects of the HZMB on the relevant harbors and channels through study. In this article, a large-scale physical model of tidal currents and sediment movement, covering the entire LBPRE with a horizontal scale of 1:900 and a vertical scale of 1:120, was presented with emphasis on the effects of the HZMB on water flow and sediment movement. The design and layout of the model are described in detail. The accuracy of the model was verified with in situ data; the results show that the simulated tidal levels, currents, and deposition in the channels are all in good agreement with measured field data. Then, evaluation on the effects of the HZMB was carried out by comparing the scenarios with and without the bridge; the effects on hydrodynamics of the LBPRE and the erosion and deposition occurring in the harbors and channels were analyzed. The following main conclusions were reached. (1) The effects of the HZMB on tidal levels, currents, and prisms were all relatively small, and the influence was limited within an area of 5 km upstream and downstream from the bridge. The construction of the HZMB tends to lead to increase of the tidal currents in Lingding Channel between the two man-made islands, which is favorable for maintenance of water depth in the channel. (2) The effects of the HZMB on erosion and deposition in the harbors and channels are insignificant. (3) The construction of the HZMB is not predicted to have substantial effects on changing the pattern of the shoals and channels in the LBPRE. (4) The HZMB is feasible as far as its effects on hydrodynamics, harbors, and channels are concerned. • A physical model of tidal currents and sediment covering the entire Lingding Bay of the Pearl River Estuary was successfully designed, built and verified with in situ data. • The physical model was successfully applied to perform experimental simulations before and after the construction of the Hong Kong–Zhuhai–Macao Bridge. • The experimental predictions based on this physical model have been proven to be reasonable and correct. [ABSTRACT FROM AUTHOR]

Abstract The aim of the present work is to study the influence of channel geometry and its assemble gap on the efficiency improvement of hydro turbine. Raising flowing velocity and the control of the pressure drop of the inlet fluid of hydro turbines are the most important hydrodynamic factors for improving their efficiency. To study these and obtain the best hydrodynamic conditions of conducting channels, channels' simulations in seven different geometrical shapes and four different assemble gabs (1, 1.25, 1.5 and 2 m) using of Lattice Boltzmann Method (LBM) were carried out. The simulation indicates that using a conducting channel which hydro turbine is installed inside can play a significant role in turbine efficiency. In addition, the type of the channel shape and assemble gap have different effects on the flow parameters such as velocity and pressure drop, and consequently can have different effects on hydro turbine efficiency too. Considering the velocity ratio and the pressure drop, it is possible to select the Airfoil-like channel as the most efficient channel. Moreover, according to the illustrations, the stream in this channel is more stable than the other channels. Likewise, one-meter assemble gap was chosen as the most efficient one than the other ones. Therefore, Airfoil-like channel with one-meter assemble gap was considered as the best channel design for increase efficiency in hydro turbine constructions. Highlights • Channels simulated in different geometries and assemble gaps. • We used of Lattice Boltzmann Method. • Airfoil-like channel is the efficient channel. [ABSTRACT FROM AUTHOR]

Abstract Comparative analyses of deep-marine sedimentological studies are hindered by the wide variety in methods of data collection, scales of observation, resolution, classification approaches and terminology. A relational database, the Deep-Marine Architecture Knowledge Store (DMAKS), has been developed to facilitate such analyses, through the integration of deep-marine sedimentological data collated to a common standard. DMAKS hosts data on siliciclastic deep-marine system boundary conditions, and on architectural and facies properties, including spatial, temporal and hierarchical relationships between units at multiple scales. DMAKS has been devised to include original and literature-derived data from studies of the modern sea-floor, and from ancient successions studied in the subsurface and in outcrop. The database can be used as a research tool in both pure and applied science, allowing the quantitative characterisation of deep-marine systems. The ability to synthesise data from several case studies and to filter outputs on multiple parameters that describe the depositional systems and their controlling factors enables evaluation of the degree to which certain controls affect sedimentary architectures, thereby testing the validity of existing models. In applied contexts, DMAKS aids the selection and application of geological analogues to hydrocarbon reservoirs, and permits the development of predictive models of reservoir characteristics that account for geological uncertainty. To demonstrate the breadth of research applications, example outputs are presented on: (i) the characterisation of channel geometries, (ii) the hierarchical organisation of channelised and terminal deposits, (iii) temporal trends in the deposition of terminal lobes, (iv) scaling relationships between adjacent channel and levee architectural elements, (v) quantification of the likely occurrence of elements of different types as a function of the lateral distance away from an element of known type, (vi) proportions and transition statistics of facies in elements and beds, (vii) variability in net-to-gross ratios among element types. Highlights • A repository for deep-marine sedimentological data has been built, known as DMAKS. • Data standardisation enables quantitative analysis of deep-marine systems. • Multi-parameter querying aids evaluation of deep-marine boundary condition effects. • DMAKS output can be used to produce predictive models of sedimentary architecture. • DMAKS can be used to produce synthetic analogues to hydrocarbon reservoirs. [ABSTRACT FROM AUTHOR]

Abstract Horizontal-bottomed power-law sections (HBP sections) are new composite channel sections, which provide more adaptability and flexibility for optimal section design than power-law sections (PL sections). Analytical solutions for wetted perimeters with general exponent parameter m are difficult to obtain, except for several definite sections, such as a horizontal-bottomed parabolic section and a horizontal-bottomed half-cubic parabola section. Therefore, there has been no detailed investigation of the general form of the HBP section. This paper present a group of general exact solutions (ratio of water surface width of PL section to water depth, and ratio of channel bed width to water depth) of the optimum hydraulic HBP section with exponent m as a parameter based on Gauss Hyper geometric mathematics and Lagrange multiplier. Many explicit exact formulas for various hydraulic parameters (flow discharge or water depth) under the condition of optimum hydraulic HBP section are also given. Error analysis shows the proposed explicit exact formulas are accurate. Next, by comparing several sections, the results indicate the cross area and wetted perimeter of horizontal-bottomed cubic sections are smaller than those of other sections for a given flow discharge. This finding means that the least amount of excavation and lining is required for construction. Therefore, the horizontal-bottomed cubic parabola section is the most economical section among the typical sections (PL sections, Rectangular, Triangular, Trapezoid, semi-cubic section and other HBP sections). This study sheds new light on a general and concise hydraulic calculation method for any HBP section with general exponent parameter m. Highlights • This paper presents a group of general exact solutions of the optimum hydraulic HBP section with exponent m as a parameter based on Gauss hyper geometric mathematics and Lagrange multiplier. • Many explicit exact formulas for various hydraulic parameters (flow discharge or water depth) under the condition of optimum hydraulic HBP section are also given. • By comparing several sections,the horizontal-bottomed cubic parabola section is the most economical section among the typical sections (PL sections, Rectangular, Triangular, Trapezoid, semi-cubic section and other HBP sections). • This study sheds new light on a general and concise hydraulic calculation method for any HBP section with general exponent parameter m. [ABSTRACT FROM AUTHOR]

Abstract A Two-stage compound channel section is commonly used in ecological channel design. This paper presents the geometric properties of the compound section and the formulae for calculating the cross-section area, wetted perimeter are obtained. Then, the explicit equations of the best hydraulic section for design are derived. Results show the best width-depth ratio of the compound section is related to some geometric parameters. Furthermore, this type of best hydraulic section is compared with the rectangular and trapezoidal sections. Results indicate that the cross-section area and wetted perimeter are less than those of rectangular and trapezoidal sections for a given flow discharge when the ratios of the compound section's roughness coefficient to those of rectangular and trapezoidal sections are less than 1.017 and 0.855, respectively. It means less lining and excavation cost is required for construction. Highlights • Geometric properties of the two-stage compound channel section are presented. • Formulae for calculating the cross-section area, wetted perimeter of the compound section are obtained. • The explicit equations of the best hydraulic section of the compound section for design are derived. • This type of best hydraulic section is compared with the rectangular and trapezoidal sections. • Quantitative values are obtained used to determine the more efficient section of the compound section. [ABSTRACT FROM AUTHOR]

Abstract Ravi Vallis is a Martian outflow channel that is widely interpreted as a product of one or more catastrophic outbursts of groundwater from adjacent Aromatum Chaos. However, solar system analogs are unknown for formation of large channels by outbursts from aquifers, and the Ravi Vallis region lacks the obvious sedimentological and mineralogical signatures expected of aqueous origins. Instead, the basic nature of this channel system is consistent with volcanic origins involving voluminous effusions of low-viscosity lavas. On bedrock slopes of only 0.2°, 50-m-deep lava flows with viscosities of 1 Pa s are predicted to have been characterized by discharge rates of ∼3 × 107 m3/s for 25-km-wide flows, with associated mechanical incision rates of ∼4 m/day and thermal incision rates of ∼2 m/day. Formation of Aromatum Chaos and the preserved 215-km-long extent of Ravi Vallis is conservatively estimated on the basis of thermal considerations to have required eruption of a minimum of ∼64,000 km3 of lava, but greater volumes would have been necessary to form the original (unknown) length of this channel system. A volcanic origin for Ravi Vallis is consistent with development of all Martian outflow channels by igneous processes, and with the broader premise that early development of immense volcanic channel systems is typical of all large rocky bodies. Highlights • Ravi Vallis has the properties expected of volcanic rather than aqueous origins. • Eruptions at Aromatum Chaos are likely to have been fed by deeply-rooted intrusions. • System development required eruption of at least ∼64,000 km3 of lava. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • MoS 2 flakes are etched in the presence of cobalt oxide by catalytic oxidation. • The oxidation results in etched structures like pits and channels on the flakes. • Transition metal dichalcogenide including S element can be etched by this method. Abstract With a growing interest in two-dimensional transition metal dichalcogenide (TMD), etching the structure of TMD for further application is a challenge due to its thermal stability by a high melting point. Here, we report on diverse etched structures in MoS 2 flakes based on the catalytic oxidation using a Co catalyst. After impregnated with a Co precursor, MoS 2 flakes were oxidized in air by induction heating to obtain an etched structure. As a result, microscopic observation revealed that diverse etched structures in the shape of a channel and a pit were created in the MoS 2 flakes. Especially, the catalytic etching by CoO nanoparticles produced two types of channels which have an angle of 120° and 150°, respectively. Also, a pit with a depth of approximately 3 nm was found on the oxidized surface of MoS 2 flakes. Our results open a new perspective to control the edge site of TMD flakes including S element as well as MoS 2 flakes. [ABSTRACT FROM AUTHOR]

Abstract The work described in this paper employs large eddy simulation and a discrete element method to study turbulent particle-laden channel flows at low concentrations (particle volume fraction 10−4–10−5), including particle dispersion, collision and agglomeration. Conventional understanding of such flows is that particle interactions are negligible, this work however demonstrates that such interactions are common at large Stokes numbers in turbulent flow. The particle-particle interaction model is based on the Hertz-Mindlin approach with Johnson-Kendall-Roberts cohesion to allow the simulation of cohesive forces in a dry air flow. The influence of different flow Reynolds numbers, and therefore the impact of fluid turbulence, on agglomeration behaviour is investigated. The agglomeration rate is found to be strongly influenced by the flow Reynolds number, with most of the particle-particle interactions taking place at locations close to the channel walls, aided by the higher turbulence levels and concentration of particles in these regions. Graphical abstract Unlabelled Image Highlights • Turbulent structure of the flow dominates motion creating particle interactions • Agglomeration increase with Reynolds number at low surface energy • Process of particle agglomeration was seen to be enhanced in two separate regions [ABSTRACT FROM AUTHOR]

Abstract Ca2+ is a universal second messenger in many signaling pathways in all eukaryotes including plants. Transient changes in [Ca2+]cyt are rapidly generated upon a diverse range of stimuli such as drought, heat, wounding, and biotic stresses (infection by pathogenic and symbiotic microorganisms), as well as developmental cues. It has been known for a while that [Ca2+]cyt transient signals play crucial roles to activate plant immunity and recently significant progresses have been made in this research field. However the identity and regulation of ion channels that are involved in defense related Ca2+ signals are still enigmatic. Members of two ligand gated ion channel families, glutamate receptor-like channels (GLRs) and cyclic nucleotide-gated channels (CNGCs) have been implicated in immune responses; nevertheless more precise data to understand their direct involvement in the creation of Ca2+ signals during immune responses is necessary. Furthermore, the study of other ion channel groups is also required to understand the whole picture of the intra- and inter-cellular Ca2+ signalling network. In this review we summarize Ca2+ signals in plant immunity from an ion channel point of view and discuss future challenges in this exciting research field. [ABSTRACT FROM AUTHOR]

Abstract The CorA Mg2+ channel is a homopentamer with five-fold symmetry. Each monomer consists of a large cytoplasmic domain and two transmembrane helices connected via a short periplasmic loop. In the Thermotoga maritima CorA crystal structure, a Mg2+ is bound between D89 of one monomer and D253 of the adjacent monomer (M1 binding site). Release of Mg2+ from these sites has been hypothesized to cause opening of the channel. We generated mutants to disrupt Mg2+ interaction with the M1 site. Crystal structures of the D89K/D253K and D89R/D253R mutants, determined to 3.05 and 3.3 Å, respectively, showed no significant structural differences with the wild type structure despite absence of Mg2+ at the M1 sites. Both mutants still appear to be in the closed state. All three mutant CorA proteins exhibited transport of 63Ni2+, indicating functionality. Thus, absence of Mg2+ from the M1 sites neither causes channel opening nor prevents function. We also provide evidence that the T. maritima CorA is a Mg2+ channel and not a Co2+ channel. Graphical abstract Unlabelled Image Highlights • Crystal structures of Tm CorA M1 Mg2+ binding sites mutants (D89K/D253K; D89R/D253R). • Release of Mg2+ from M1 sites hypothesized to cause opening of channel. • Both mutant structures still in closed conformation despite absence of Mg2+ at M1 sites. • Mutant CorA proteins still show transport of 63Ni2+, indicating functionality. • Absence of Mg2+ from M1 sites does not cause channel opening or prevent function. [ABSTRACT FROM AUTHOR]

Highlights • Granular flows over a static pile have been investigated in an inclined channel. • The velocity profiles of the avalanches follow a pure parabolic decrease. • The velocity profiles can be predicted with the flow rate. • A shear-thinning viscosity model accounting for the velocity profile is deduced. Abstract Granular flows over a static pile have been investigated in an inclined channel. Instead of dividing the granular motions into fast flow with linear velocity profile and creeping motion with exponential velocity profile, we set the boundary of the flowing layer as the locus of points where the particle velocity decreases down to 1% of the surface velocity, and unify the granular motions with a single velocity profile making the application more convenient. The velocity profile of the granular flows follows a parabolic form, and can be predicted once the surface velocity or the flow rate is determined. Moreover, we propose a viscosity model to account for the parabolic velocity profile in the flowing layer, and validate this model by employing FT4 Powder Rheometer. The apparent viscosity is approximated as the sum of frictional and collisional-translational contributions. In analogy with the turbulent mixing-length theory, the momentum transfer is enhanced by the fluctuation, and the apparent viscosity in the granular flows depends both on the flowing-layer thickness and the local shear rate. Graphical abstract Image, graphical abstract [ABSTRACT FROM AUTHOR]

• The flexural behavior of one-way RC precast flat slabs was studied. • The effect of strengthening the slabs with steel sections from above was investigated. • The net strength gain in flexure after the application of an overlay is calculated. • The moment capacities were compared with the predictions using ACI 318-19. In South Carolina, there are one-way precast RC flat slab bridges that were constructed in the 1950 s for H-10 and H-15 design trucks (lower than the current design standards) and have deteriorated over time. To ensure public safety and continued usage, strengthening the bridges is imperative. Various methods exist for flexural strengthening, including application of UHPC from above and strengthening from below with FRP, steel plates, and external prestressing. However, these methods may compromise the ductile behavior of the slabs and they are also challenging, labor-intensive, and expensive to apply. The innovation of this paper lies in investigating the methods for strengthening from above that have the potential to improve both the flexural strength and ductility of slabs, while offering advantages in terms of ease of implementation and cost-effectiveness compared to existing methods. Five slabs obtained from decommissioned bridges in South Carolina were tested under monotonic loading to failure: one reference slab; one slab strengthened with steel channel sections from above; one slab strengthened with steel plate sections from above, and two slabs connected at the joint by near surface mounted steel rebars for strengthening. Strengthening the slabs with steel channel sections from above effectively improved the flexural strength and ductility of the slabs while being more economical and easier to implement than other methods of strengthening. Following strengthening, some slabs may require overlays to cover the steel sections and ensure that bridge traffic may go on them. Even after accounting for reduction in strength gain due to the deadload of the overlay, a positive net strength gain in measured peak moment was observed in the strengthened slabs. The moment capacities of the slabs, as determined through design calculations following the ACI 318–19 code, exhibit a good agreement with the measured peak moment observed in experimental tests, thus validating their reliability as a dependable alternative to solely relying on experimental tests. [ABSTRACT FROM AUTHOR]

The present work focuses on the influencing factors for the performance enrichment of solar still, which serves as one of the sources of cleaner production of freshwater in a hot environment. This enrichment in yield has been achieved through channel attachments and optimized water depth. The different positions of interior and exterior temperatures are measured and compared with/without the channel attachment of the solar still. The results reveal that the water yield from the double slope is found more with channel attachments in the solar still at the minimum water depth of 1 cm. The different month yield rates are compared with and without channel attachment. Furthermore, the theoretical exergy analysis has been conducted for various components of double slope solar still and compared with experimental findings. The yield rates for 1 cm basin water depths in March, April, and May are as follows: for the modified system - theoretical rates of 2.490, 2.760, and 2.900 L m−2 and experimental rates of 2.285, 2.530, and 2.770 L m−2; for the base system - theoretical rates of 2.090, 2.200, and 2.475 L m−2 and experimental rates of 1.920, 2.110, and 2.270 L m−2. In comparison to the basic system, the modified DSSS yield rate increased from 6.66% to 22.02%, and the exergy efficiency of the DSSS with and without a channel attachment are 8.42% and 4.14%, respectively. The present method can be adopted to solve the drinking water shortage problem at hot environments. [Display omitted] • Double -slope solar still with channel attachment is conducted for Chennai climatic condition. • The better yield was found at the lowest basin water depth of the double slope solar still. • The channel attachment increased the utilization of the solar energy and increased the yield of the solar still. • Energy-exergy performance analysis was done for solar still with and without channel attachment. [ABSTRACT FROM AUTHOR]

• The effects of a magnetic field on a type of Casson hybrid nanofluid flow between two infinite parallel plates is examined. • Two different hybrid nanofluids are utilized to enhance the heat transfer features. • Porosity impacts is taken into account. • Numerical fractional solutions are presented for the impact of several distinct influential parameters. The Casson fluid flow of an unsteady and viscous type hybrid nanofluid between two parallel infinite plates is highlighted in this study as being affected by a magnetic field. The two nanoparticles are copper (Cu) and aluminum oxide (Al 2 O 3) , and their physical characteristics have been anticipated as based fluids like water (H 2 O) and sodium-alginate (Na C 6 H 7 O 6). The derived fractional model is inspected with the assistance of Laplace transformation utilizing the recent and modified description of the Prabhakar fractional derivative. It statistically and graphically examined how different constraints affect various nanoparticles. Therefore, we have concluded that a rise in the volumetric percentage ratio causes a decrease in fluid velocity. Furthermore, this can also be seen that (H 2 O - C u - A l 2 O 3) hybrid nanofluid has a greater impact on thermal and momentum profile than (N a C 6 H 7 O 6 - C u - A l 2 O 3) hybrid nanofluid due to the physical properties of the investigated nanoparticles and base fluids. The velocity profile also decelerates as a result of the improvement in Casson fluid parameter values. The overlapping of the attained results and existing literature also validate this study. [ABSTRACT FROM AUTHOR]

Highlights • Fluid-structure interaction and mixed convection in cavity-channel assembly is studied. • The vertical wall(s) of the cavity are deformable (elastic). • Arbitrary Lagrangian–Eulerian (ALE) approach with finite Element method is used. • The deformable walls improve the heat transfer rate compared with rigid walls. • The role of the deformable walls is prominent at dominant natural convection. Abstract This paper investigates the unsteady mixed convection in a cavity-channel assembly resulting from the interaction between fluid flow and a deformable (elastic) walls. A discrete heat source is fixed at the bottom of the cavity while the other walls of the assembly are thermally insulated. The upper side of the cavity is exposed to a channel flow. The governing equations of the interaction between the fluid and elastic wall are solved using Arbitrary Lagrangian–Eulerian (ALE) approach with Finite Element method. Effects of elasticity modulus, buoyancy to viscous ratio and the inertia to viscous ratio are studied by considering different ranges of Cauchy, Richardson and Reynolds numbers. It is found that the presence of the elastic wall(s) improve the heat transfer rate by 17% compared with rigid walls of the cavity. The role of the elastic wall is pronounced at Ri = 10. Graphical abstract Image, graphical abstract [ABSTRACT FROM AUTHOR]

The fully developed mixed convection channel flow in a porous medium saturated with a nanofluid in suspension of nanoparticles and microorganisms driven by its upper moving stripy wall is investigated. By a set of similarity variables, we reduce the governing equations of the conservation of total mass, momentum, thermal energy, nanoparticle volume fraction and microorganisms to four coupled nonlinear ordinary differential equations. The accurate solutions are obtained analytically. Besides, effects of physical parameters on important physical quantities are examined and discussed in detail. The transport mechanism of heat and mass due to the permeability, the slip parameter, the thermophoresis and Brownian diffusions, as well as the bioconvection diffusion is presented. As far as we know, the channel flow of a nanofluid with accelerating wall(s) is not yet considered before. Hence this investigation is original and new. It is expected that the current analysis can be applied in the petroleum engineering where nanoparticles and microorganisms play a role on exploitation efficiency enhancement and energy conservation. [ABSTRACT FROM AUTHOR]

The superfamily of heme‑copper oxidoreductases (HCOs) include both NO and O 2 reductases. Nitric oxide reductases (NORs) are bacterial membrane enzymes that catalyze an intermediate step of denitrification by reducing nitric oxide (NO) to nitrous oxide (N 2 O). They are structurally similar to heme‑copper oxygen reductases (HCOs), which reduce O 2 to water. The experimentally observed apparent bimolecular rate constant of NO delivery to the deeply buried catalytic site of NORs was previously reported to approach the diffusion-controlled limit (10 8 –10 9  M −1  s −1 ). Using the crystal structure of cytochrome-c dependent NOR (cNOR) from Pseudomonas aeruginosa , we employed several protocols of molecular dynamics (MD) simulation, which include flooding simulations of NO molecules, implicit ligand sampling and umbrella sampling simulations, to elucidate how NO in solution accesses the catalytic site of this cNOR. The results show that NO partitions into the membrane, enters the enzyme from the lipid bilayer and diffuses to the catalytic site via a hydrophobic tunnel that is resolved in the crystal structures. This is similar to what has been found for O 2 diffusion through the closely related O 2 reductases. The apparent second order rate constant approximated using the simulation data is ~5 × 10 8  M −1  s −1 , which is optimized by the dynamics of the amino acid side chains lining in the tunnel. It is concluded that both NO and O 2 reductases utilize well defined hydrophobic tunnels to assure that substrate diffusion to the buried catalytic sites is not rate limiting under physiological conditions. [ABSTRACT FROM AUTHOR]

Ca 2+ flux across the inner mitochondrial membrane (IMM) regulates cellular bioenergetics, intra-cellular cytoplasmic Ca 2+ signals, and various cell death pathways. Ca 2+ entry into the mitochondria occurs due to the highly negative membrane potential (ΔΨ m ) through a selective inward rectifying MCU channel. In addition to being regulated by various mitochondrial matrix resident proteins such as MICUs, MCUb, MCUR1 and EMRE, the channel is transcriptionally regulated by upstream Ca 2+ cascade, post transnational modification and by divalent cations. The mode of regulation either inhibits or enhances MCU channel activity and thus regulates mitochondrial metabolism and cell fate. [ABSTRACT FROM AUTHOR]

Continuous sediment supply in the Aka-kuzure landslide scar, in the tectonically active alpine Southern Japanese Alps, was investigated using airborne light detection and ranging data in 2000, 2003, 2007 and 2012. In addition, we focused on the spatial variability of denudation patterns based on topographical analyses using DEMs. Denudation volume for the past 12 years reached about 10 6  m 3 and mean annual denudation rate ranged from 0.25 to 0.31 m/yr. Topographical analyses revealed that sediment supply in the scar consists of a combination of two denudation types, sporadic-deep and wide-thin. These denudation types have different roles in the topographical development of the landslide scar. Sporadic-deep type supplies less volume than wide-thin type but still contributes to channel development, as it mainly occurs on lower-order streams and tends to change the convex slope into a concave slope. In contrast, although denudation depth of the wide-thin type is thin, the area affected by this type extends to the whole landslide scar. Consequently, the wide-thin type accounts for most of the total volume lost, for which detachment by frost shattering is suggested as an important role. [ABSTRACT FROM AUTHOR]

Hierarchical classifications are used in the field of clastic deep-marine sedimentary geology to assign spatial and temporal order to the sedimentary architecture of preserved deep-marine deposits and to genetically related modern landforms. Although such classifications aim to simplify the description of complex systems, the wide range of developed approaches limits the ease with which deep-marine architectural data derived from different sources can be reconciled and compared. This work systematically reviews and compares a selection of the most significant published hierarchical schemes for the description of deep-marine sedimentary architecture. A detailed account of each scheme is provided, outlining its aims, environmental contexts and methods of data collection, together with the diagnostic criteria used to discern each hierarchical order from observational standpoints (e.g., via facies associations, geometry, scale and bounding-surface relationships) and also on interpretational grounds (e.g., processes and sub-environments of deposition). The inconsistencies and pitfalls in the application of each scheme are also considered. The immediate goal of this review is to assist sedimentologists in their attempts to apply hierarchical classifications, both in the contexts in which the classifications were originally developed and in alternative settings. An additional goal is to assess the causes of similarities and differences between schemes, which may arise, for example, in relation to their different aims, scales of interest or environmental focus (e.g., channelized or lobate units, or both). Similarities are found between the approaches that commonly underlie the hierarchical classifications. Hierarchies are largely erected on the basis of common types of observations, in particular relating to the lithology and geometries of deposits, in association with analysis of bounding-surface characteristics and relationships. These factors are commonly considered in parallel with their associated genetic interpretations in terms of processes or (sub-) environments of deposition. A final goal of the review is to assess whether a universal standard for the description of deep-marine sedimentary architecture can be devised. Despite the commonalities that exist between classification approaches, a confident reconciliation of the different hierarchical classification schemes does not appear to be achievable in the current state of knowledge. [ABSTRACT FROM AUTHOR]

Mass-transport deposits (MTDs) generate seafloor topography that can strongly influence the stratigraphic architecture of submarine channels. In deep-water depositional environments, both MTDs and turbidity currents are commonly fed into basins from a single point source, and turbidites may be observed ponding on top of, between, and beside MTDs. This study uses core data and 3D seismic reflection data to classify two major types of MTDs, 1) long-runout MTDs, which are radial in plan view and mounded, and 2) short-runout MTDs, which are elongate and weakly layered. Both MTD types deposited transversely into a deep-water axial channel belt in the lower Puchkirchen Formation in the Molasse Basin of Austria. Unlike longitudinally-emplaced MTDs previously identified in the upper Puchkirchen Formation, the surface topography of transversely-emplaced MTDs, especially those of the long-runout MTDs, provided accommodation for the ponding of sediments on a scale similar to that of large supra-MTD ponded turbidite intervals identified globally. Moreover, both types of transversely-emplaced MTDs enhanced syn-tectonic northward migration of the northern margin of the channel belt and delivered large quantities of fine-grained material that likely contributed to the mud-rich lithofacies that comprise a significant fraction of the lower Puchkirchen Formation. Our work suggests that supra-MTD ponded deposits could contain hydrocarbon reservoir units in regions previously regarded as waste zones. More broadly, this study characterizes how transversely-emplaced MTDs influence seafloor topography, submarine channel morphology, and the distribution of reservoir facies in a depositional system characterized by axial sediment transport. [ABSTRACT FROM AUTHOR]

Dopant analysis in next-generation semiconductor devices has become increasingly difficult for traditionally used analytical techniques. Atom probe tomography has been viewed by some as a possible solution to these challenges because of its three-dimensional capabilities, forcing the atom probe to mature at a rapid pace in this particular field. This work presents a well-rounded analysis of how APT can be used to examine B dopant diffusion into the channel of a next-generation FinFET, where the channel dimensions and the number of dopants atoms are significantly smaller than any devices measured by APT to date. Complimentary EELS analysis of the gate and channel provides a better understanding of how distortions and artifacts in the APT reconstruction affect the overall integrity of the dataset. Dopant measurements in the channel are confirmed through in-depth mass spectrum analysis and compared with values proposed by TCAD modeling. [ABSTRACT FROM AUTHOR]

Submarine fans in tectonically active continental-slope basins are targets of petroleum exploration and production. These slope fans commonly comprise compensationally stacked sandy and muddy architectural elements, including mass-transport deposits, weakly confined to distributary channel-and-lobe deposits, and leveed-channel deposits. The lateral continuity and vertical connectivity of these architectural elements are important uncertainties in reservoir characterization that influence fluid-flow behavior during hydrocarbon production. Here, we use a simple forward stratigraphic model to simulate the stratigraphic patterns and illuminate the likely distribution of fine-scale, sub-seismic heterogeneity in a slope fan. We used published seismic-reflection horizons from the tectonically active Columbus basin, offshore Trinidad, to define the top and base of a Pleistocene submarine fan. We then simulated the stratigraphic evolution of the slope fan with a series of DionisosFlow™ forward stratigraphic models. All variables were kept constant during the simulations in order to test the hypothesis that the autogenic evolution of the surface topography alone, as a result of erosion and deposition, can produce compensational-stacking patterns common in submarine fans. A reference-case model is similar to the thickness trend of published isochron maps of the Trinidad slope fan. The reference-case model also produced patterns of compensational stacking. Varying the time step impacts the heterogeneity of the model. Shorter time steps are characterized by less sediment accumulation, which results in less sediment diversion during the subsequent time step, more gradual migration of channel deposits, shorter offset distances of depocenters, and shorter length-scale heterogeneity compared to longer time steps. Thus, a key characteristic of slope-fan deposits is autogenic compensational stacking, without any external forcing, which governs heterogeneity in these reservoirs. Furthermore, our results suggest that relatively simple diffusion-based models can produce realistic compensation patterns and future work will be focused on higher-resolution model calibration to seismic-reflection data and the influence of input variables on heterogeneity of channel-and-lobe deposits of slope fans. [ABSTRACT FROM AUTHOR]

Common traditional screens (screens perpendicular and vertical to the flow direction) face extensive problems with screen blockage, which can result in adverse hydraulic, environmental, and economic consequences. Experimentally, this paper presents an advanced trash screen concept to reduce traditional screen problems and improve the hydraulic performance of screens. The traditional screen is re-developed using a triangular V shape with circular bars in the flow direction. Triangular V-shaped screen models with different angles, blockage ratios, circular bar designs, and flow discharges were tested in a scaled physical model. The analyses provide promising results. The findings showed that the head loss coefficients were effectively reduced by using the triangular V-shaped screens with circular bars (α < 90°) in comparison with the traditional trash screen (α = 90). Additionally, the results indicated that the head loss across the screen increased with increasing flow discharge and blockage ratio. The losses considerably increase by large percentages when the screen becomes blocked by 40%. Low head losses were recorded at low screen angles for the circular bars. A new head loss equation is recommended for triangular screens with circular bars. [ABSTRACT FROM AUTHOR]

The study of the forced convection in a channel has many practical applications. In this paper, the forced convection heat transfer from surface mounted blocks attached to the bottom wall of a horizontal channel with nanofluid is numerically studied by the second-order lattice Boltzmann method (LBM). The effects of Reynolds numbers and geometrical parameters of the blocks in different aspect ratios on the flow field and temperature distribution for various volume fractions of nanofluid (φ = 0, 0.01, 0.03 and 0.05) are analyzed. Also, the influence of these parameters is investigated on the local and average Nusselt numbers. It is concluded that heat transfer in channels can be enhanced by using the block on the walls and adding nanoparticles. There is a maximum value of 39.04% increase in average heat transfer coefficient for all the examined cases compared to the base fluid (i.e., water). [ABSTRACT FROM AUTHOR]