Intermediate Connection Research Articles

Parametric optimization of SIP connection geometry in CFS-MRF structures: A finite element study

The structural buildings should be designed to resist both static and dynamic loads. There are different types of structural systems that can support seismic loads. Moment-resisting frames (MRFs) are widely used for seismic purposes, relying on the plastic deformations occurring between the beam and column. The main problems of cold-formed steel sections in MRFs during seismic loads are premature local and distortional buckling, which cause severe damage under strong earthquakes, such as early loss of connection strength, low ductility, and low energy dissipation. This paper clarifies the performance of the CFS section with steel interconnected part (SIP) in moment-resisting frames (MRFs) in many aspects using finite element (FE) procedures. The study summarizes the required dimensions of SIP to achieve optimal behavior for the beam-column connection. Additionally, an advanced connection consisting of SIP and four pairs of out-of-plane stiffeners has been examined. The locations of the out-of-plane stiffeners have been carefully selected to stabilize the connection. A cantilever beam connection has been used to represent an MRF in an advanced way. The connection consists of 2 C channel back-to-back beams connected with a through plate with sixteen bolts. Numerical models have been developed and verified with experimental tests under both monotonic and cyclic loading. The characteristics and creation of the numerical model are well illustrated in this paper. Cyclic loading has been applied according to AISC protocol, which is used to test the performance of the steel connections, as well as to classify the connection according to different design codes. The results show that increasing the plastic moment capacity of the CFS section decreases the required SIP dimensions to achieve optimal behavior by the connection. Additionally, it has been found that using out-of-plane stiffeners in particular locations with SIP increases energy dissipation on average by 74 %. Using stiffeners with SIP can upgrade the classification of the connection from an ordinary or intermediate moment connection to a special moment connection without the need to increase the CFS cross-section area or reduce the slenderness ratio, which in turn reduces the overall costs of construction.

Flexural Behavior of Precast Rectangular Reinforced Concrete Beams with Intermediate Connection Filled with High-Performance Concrete

Precast rectangular reinforced concrete (PRRC) beams are joined on construction sites using concrete in situ to achieve the desired length. Limited research exists on the effect of intermediate connection shapes and the types of infilled concrete on the flexural performance of PRRC beams. This paper presents a comprehensive experimental and numerical investigation into the performance of PRRC beams with various intermediate connection geometries and infilled materials under flexural loading. The study examines rectangular, triangular, and semi-circular intermediate connections, along with the performance of beams infilled with normal concrete (NC), engineered cementitious composites (ECC), ultra-high-performance ECC (UHPECC), and rubberized ECC (RECC). The experimental results indicate that the rectangular intermediate connection exhibits superior performance in terms of strength and energy absorption compared to the triangular and semi-circular shapes. Beams incorporating UHPECC demonstrated the most significant improvements in strength and energy absorption, outperforming those with ECC and RECC for any shape of intermediate connection. Moreover, beams with rectangular connections and UHPECC infill exhibited the most significant increase in energy absorption and ultimate load compared to the beams with ECC and RECC. The ultimate load of the beams with UHPECC and tensile reinforcement bar diameters of 10 mm and 12 mm increased by 13% and 29%, respectively, compared to the control beam. The energy absorption of the beams with tensile reinforcement bar diameters of 10 and 12 mm was found to be 75% and 184% higher, respectively, than the control beam. In addition, an increase in tensile bar diameter was found to enhance both the energy absorption and the ultimate load capacity of the beams, regardless of the type of infill concrete. Beams incorporating UHPECC demonstrated the most significant improvements in strength and energy absorption, outperforming those with ECC and RECC. In particular, beams with rectangular connections and UHPECC infill exhibited an increase in energy absorption and ultimate load of up to 184% and 29%, respectively. UHPC was calculated to be as high as 184%, and 29%, respectively, compared to the control beams. In addition, an increase in tensile bar diameter was found to enhance both energy absorption and ultimate load capacity. Finite element modeling (FEM) was developed and validated against the experimental results to ensure accuracy. A parametric study was conducted to study the effects of various concrete types in triangular and semi-circular connections, as well as the influence of intermediate connection length on semi-circular connections under flexural loads. The findings reveal that increasing the length of intermediate connections increases the ultimate load of the beams.

Peculiarities of investment and innovation potential in the assessment of the development of agribusiness enterprises

Three main criteria of investment-innovation potential of agricultural sector enterprises are identified: investment-innovation potential is a set of resources necessary for investment-innovation activities; investment and innovation potential is primarily related to the possibility and conditions (both internal and external) of using resources; investment and innovation potential should be aimed at the optimal use of investment and innovation resources to ensure the effective operation of this development subject. This allows for the identification of resource, organizational, economic and performance components that are key components of investment and innovation opportunities. A step-by-subject characterization of the investment-innovation potential of agro-industrial complex enterprises and a methodology for assessing the investment-innovation potential have been developed, which allows to qualitatively assess the investment-innovation potential of agricultural and processing enterprises (including special groups of indicators that take into account the specifics of their activities) and evaluate and compare them among themselves. It is proved that the inactivity of agricultural commodity producers in mastering the achievements of science and technology is due to the lack of a developed intermediate connection between science and production, which provides the most complete information about the modern achievements of science and technology to producers of raw materials. According to the results of the conducted research, it was established that at the current stage of development in domestic agriculture, the main subjects of innovative infrastructure can become agricultural technology parks and information and consulting centers, which are part of a single information and consulting service. Considering the peculiarities of the domestic agro-industrial complex, it is considered most expedient to create an agro-technological park in the form of a non-commercial partnership, which will contribute to the integration of multifaceted resources. organizations, mainly highly efficient agricultural commodity producers and educational establishments of higher education institutions, capable of carrying out innovative activities to achieve a common goal - innovative development of the agrarian sector of the economy. Agrotechnoparks should be created based on the product base, that is, their activities should be aimed at innovative development of agricultural production and the development of certain types of products. Agrotechnopark can be considered as a set of administrative, production, educational, research and marketing divisions.

Epidermal growth factor receptor inhibition leads to cellular phenotype correction of DSP-mutated keratinocytes.

Desmoplakin (DSP) is a desmosomal component expressed in skin and heart, essential for desmosome stability and intermediate filament connection. Pathogenic variants in the DSP gene encoding DSP, lead to heterogeneous skin, adnexa and heart-related phenotypes, including skin fragility, woolly hair (WH), palmoplantar keratoderma (PPK) and arrhythmogenic/dilated cardiomyopathy (ACM/DCM). The ambiguity of computer-based prediction analysis of pathogenicity and effect of DSP variants, indicates a necessity for functional analysis. Here, we report a heterozygous DSP variant that was not previously described, NM_004415.4:c.3337C>T (NM_004415.4(NP_004406.2):p.(Arg1113*)) in a patient with PPK, WH and ACM. RNA and protein analysis revealed ~50% reduction of DSP mRNA and protein expression. Patient's keratinocytes showed fragile cell-cell connections and perinuclear retracted intermediate filaments. Epidermal growth factor receptor (EGFR) is a transmembrane protein expressed in the basal epidermal layer involved in proliferation and differentiation, processes that are disrupted in the development of PPK, and in the regulation of the desmosome. In skin of the abovementioned patient, evident EGFR upregulation was observed. EGFR inhibition in patient's keratinocytes strongly increased DSP expression at the plasma membrane, improved intermediate filament connection with the membrane edges and reduced the cell-cell fragility. This cell phenotypic recovery was due to a translocation of DSP to the plasma membrane together with an increased number of desmosomes. These results indicate a therapeutic potential of EGFR inhibitors for disorders caused by DSP haploinsufficiency.

220V/50Hz Compatible Bipolar Quantum-Dot Light-Emitting Diodes.

Alternating current (AC)-driven quantum-dot light-emitting diodes (QLEDs) are superior to direct current-driven QLEDs because they can be directly integrated into household AC electricity and have high stability. However, achieving high-performance AC-driven QLEDs remains challenging. In this work, a bipolar QLED with coplanar electrodes is realized by horizontally connecting a regular QLED and an inverted QLED in series using an Al bridging layer. The bipolar QLED can be turned on with either a positive or a negative bias voltage, with a high external quantum efficiency (EQE) of 22.9%. By replacing the Al with Ag, the resistances of the electron transport layers are effectively reduced, and thus the bipolar QLED shows an enhanced brightness of 16370cdm-2 at 15V. By connecting multiple bipolar QLEDs in series, the resulting light source can be directly driven by a 220V/50Hz household power supply without the need for back-end electronics. The bipolar QLED can also be realized by vertically stacking a regular QLED and an inverted QLED with a metallic intermediate connection layer. It is demonstrated that the coplanar or vertical bipolar QLEDs could find potential applications in household AC electricity play-and-plug solid-state lighting and single- or double-sided displays.

Development of an antimicrobial and antifouling PES membrane with ZnO/poly(hexamethylene biguanide) nanocomposites incorporation

Although polyethersulfone (PES) membranes are extensively utilized in water and wastewater treatment, they typically encounter serious bio/organic fouling problems. In this work, an antimicrobial and antifouling PES membrane was developed through incorporating novel ZnO/PHMB (zinc oxide/ polyhexamethylene biguanide hydrochloride) nanocomposites on the surface of a commercial PES membrane, with PDA (polydopamine) serving as an intermediate connection layer. XPS, along with synchrotron-based XRF and ATR-FTIR results confirmed the successful synthesis of the ZnO/PHMB nanocomposites and ZnO/PHMB membranes. The ZnO/PHMB nanocomposites exhibited an impressive antimicrobial rate of 99.99 % with a minimal amount of PHMB addition (wtZnO:wtPHMB = 1:0.01). The concentration of the ZnO/PHMB nanocomposites had the most significant impact on the antimicrobial performance of the ZnO/PHMB membrane. The 600ZP membrane (i.e., the PES membrane modified with 600 mg/L ZnO/PHMB nanocomposites) emerged as the optimal choice, as evidenced by its commendable antimicrobial performance (92.80 %), water flux (249.02 LMH), RB (Rose Bengal sodium salt) rejection (93.96 %), and cost-benefit considerations. Compared to the pristine PES membrane, the 600ZP membrane showed 5.32 %, 15.76 %, and 7.62 % increased hydrophilicity, water flux, and RB rejection rate, respectively. Additionally, the 600ZP membrane possessed a bactericidal rate of 92.80 % and a flux recovery rate of 89.24 % after three cycles of SA (sodium alginate) filtration, indicating enhanced antimicrobial and antifouling capacities. The 600ZP membrane exhibited a remarkable 91.05 % higher water flux following prolonged (72 h) treatment of secondary effluent, compared to the PES membrane. Attribute to the increased hydrophilicity, outstanding antimicrobial activity, as well as excellent stability and durability, the as-prepared ZnO/PHMB membrane shows great potential for wastewater treatment.

Experimental and numerical investigations of precast circular reinforced concrete slender columns with intermediate connection

This paper carries out experimental and numerical investigations on the axial performance of circular Reinforced Concrete (RC) precast slender columns with an intermediate connection. A series of tests are carried out to study the effects of longitudinal reinforcement ratio (ρ), and embedded length of steel bars (Lb) of precast columns on their axial performance under concentric loading. Test results show that increasing the reinforcement ratio and the embedded length of the precast columns significantly improves the axial performance of the precast slender columns. Nonlinear finite element models (FEM) are developed to simulate the performance of the columns experimentally observed. The accuracy of the FEM is validated against the test results and found to reasonably predict the axial performance of tested columns.

Heat transfer performance investigation of rotating U-channel supercritical pressure hydrocarbon fuel with intermediate connection section

To meet the challenge of the high temperatures faced by hypersonic vehicle electricity provision turbine blades, the blades are cooled with hydrocarbon fuel. For reducing the friction loss and improving the thermal performance, this paper designs and investigates the fuel flow mechanism and heat transfer law in the rotating channel with and without intermediate connection section. The results show that the channel with intermediate connection sections can reduce the friction coefficient of hydrocarbon fuel under rotating conditions and enhance the thermal performance. The connection section width H = 2D channel exhibits the best thermal performance and the lowest coefficient of friction. Compared to the channel without intermediate connection section, the thermal performance of the channel with connection section width H = 2 D is maximally enhanced by 3.71 times and the friction coefficient is maximally reduced by 98.9%. Compared to stationary, the thermal performance of the channel with a width of connection section H = 2 D is maximally enhanced by 10.78 times in rotating. Connecting sections will gradually replace 180° top turning sections. When the inlet temperature increases, the thermal performance of the channel can be improved by decreasing the width of the intermediate connecting section.

Experimental and numerical studies of circular precast concrete slender columns with intermediate connection filled with high-performance concrete

Precast concrete (PC) slender columns with intermediate connections are often used in building construction. However, no studies have been performed on the behavior of PC slender columns with intermediate connections filled with high-performance concrete namely engineering cementitious composites (ECC) and strain hardening cementitious composites (SHCC). This paper presents the testing and computer modeling of axially loaded PC slender columns with splices filled with ECC and SHCC. Experimental program and results are presented on nineteen PC slender columns under concentric compressive load up to collapse. The test parameters include the longitudinal reinforcement (µ) ratio, and embedded length of steel bars/infilled concrete connection (Le). Three different reinforcement ratios of 0.027, 0.031, and 0.036 are considered. The embedded length of steel bars/intermediate concrete connection varies from 15D, 22.5D, and 30D where D is the bar diameter. Experimental results indicate that the use of longer steel bars/intermediate concrete connection and a higher reinforcement ratio can significantly enhance both the cracking and ultimate loads of PC slender columns with an intermediate concrete connection. The elastic stiffness of the PC slender columns with ECC and SHCC connection is found to increase by 150% and 93%, respectively when compared to the control specimen. Similarly, filling the splice of the PC columns with ECC and SHCC improves the energy absorption capacity by 107% and 138%, respectively. Nonlinear three-dimensional finite element models (FEMs) are developed accounting for the initial imperfection of the slender columns and their accuracy is validated by experimental results. It is shown that the FEM can provide an accurate simulation of the performance of PC columns with splice connection.

Flexural performance of precast circular reinforced concrete members with intermediate connection filled with ultra-high-performance-concrete

Precast Reinforced concrete (RC) columns with circular sections are increasingly being utilized in the construction of RC structures. This paper reports investigations into the flexural behavior of precast circular RC members with an intermediate connection filled with Ultra-High-Performance-Concrete (UHPC). Experimental program and results are described of twelve RC circular members tested under four-point loads up to collapse. Of the twelve columns, three of them are solid ones without intermediate connection, while nine of them are precast Normal Concrete (NC) panels connected with UHPC. The studied parameters are the existence of an intermediate connection (with and without connection), the ratio of longitudinal reinforcement (µ) ratio and the length of steel bars embedded in the UHPC connection (Le). Three concrete types are used including Normal Concrete (NC), Strain Hardening Cementitious Composite (SHCC), and UHPC. Test results show that increasing the reinforcement ratio and the embedded length of the steel bars increases the strength and energy absorption of members. Finite element models (FEMs) developed using ABAQUS are presented for capturing the responses of RC columns incorporating different concrete types. The good agreement between computer simulation and experimental results suggests that the FEMs can be utilized to undertake further parametric studies with confidence.

The Intermediate Connection of Subcells in Si-based Tandem Solar Cells.

Tandem solar cells are rationally designed and fabricated by stacking multiple subcells to achieve power conversion efficiency well above the Shockley-Queisser (SQ) limit. There is a large selection pool for the subcell candidates, such as Si, III-V, Kesterite, Perovskite, and organic solar cells. A series of different combinations of these subcells have been successfully demonstrated in practical tandem solar cell devices. However, there has not been a systematic summary of how to connect subcells in a tandem solar cell using a practical, cost-effective, and efficiency-beneficial fashion. In this work, the connection manners of subcells within a tandem cell are classified into three main categories, performing sequential growth, using the physical connection, and applying an intermediate layer, focusing on systematical description of intermediate layers using different materials. The advantages and disadvantages of these connection methods and their applicability to tandem cell types are further elaborated using two typical example models, III-V/Si and Perovskite inclusive tandem cell devices. Eventually, this work can provide useful guidance on how to carry out a suitable intermediate connection in the design of tandem solar cells depending on the selected subcells and device structure.

A resonant inertial impact rotary piezoelectric motor based on a self-clamping structure

A resonant inertial impact rotary piezoelectric motor based on a self-clamping structure is designed, assembled, and tested. The designed piezoelectric motor mainly includes a rotor (two vibrators, preload mechanism, and intermediate connection mechanism), a clamping mechanism, and another auxiliary mechanism. The piezoelectric ceramic sheet on the rotor drives the vibrator to swing under the excitation of a single harmonic wave. Because there is a clamping mechanism formed by the combination of clamp baffle and fixed clamp ring, thus the half-cycle resonant rotation of the rotor can be effectively completed, and repeated harmonic excitation can realize the unidirectional continuous rotation and swing of the rotor. The whole excitation process of the motor is in a resonance state, which has significant advantages, such as low friction and simple structure, compared with the traditional quasi-static piezoelectric motor. The structure of the piezoelectric motor is designed and analyzed using COMSOL5.5 software and then the motor performance is tested and analyzed by building an experimental platform to verify the feasibility of the motor design. The final experimental results show that the optimal working frequency of the piezoelectric motor is 150 Hz, which is consistent with the characteristic frequency of the simulation. When the motor prototype is under the conditions of optimal operating frequency 150 Hz, voltage 240 Vp-p, and preload torque 7.8 N.mm, the maximum angular speed can reach 2.4 rad/s, the maximum load can reach 27.8 N mm and the maximum resolution of the movement angle can reach 0.941°.

Numerical investigation of precast concrete frames with grouted sleeves and intermediate connections

It has previously been concluded that the seismic performance of Precast Concrete (PC) frames with grouted sleeves is inferior to that of corresponding Reinforced Concrete (RC) frames. In order to both improve the seismic performance and reduce the construction cost as much as possible, a construction technique referred to as an ‘intermediate connection’ was proposed and used for PC frames. The basic design philosophy of the ‘intermediate connection’ is that PC columns were joined in their central region where the bending moment is reduced. In order to study the effect of intermediate connections, numerical simulations were implemented using modelling methods that were validated by comparing numerical results with experimental data of columns, joints and frames from previous studies. Incremental Dynamic Analysis (IDA) and a probabilistic based approach were used to derive fragility functions for the considered PC and RC frames, and Cost Analysis was undertaken to evaluate the practicability of the improvements for PC frames with grouted sleeves.

Minimizing Energy Barrier in Intermediate Connection Layer for Monolithic Tandem WPeLEDs with Wide Color Gamut

AbstractPerovskite light‐emitting diodes (PeLEDs) show promising prospects in the wide color gamut display owing to their ultra‐narrow full width at half maximum (FWHM). However, up to now, all perovskite white LEDs integrated by standard red, green, and blue perovskite emitters, namely, monolithic white PeLEDs (WPeLEDs), have been rarely reported, owing to facing some issues, e.g., solvent incompatibility in solution technique, ion exchange, and energy transfer between different emission centers. Herein, centered on these issues, an optimal intermediate connection layer (ICL) of Po‐T2T/LiF/Ag/HAT‐CN/MoO3 is adopted to successfully develop monolithic tandem multicolor PeLEDs and WPeLEDs for the first time. The multicolor PeLEDs can achieve the best external quantum efficiency of 1.8% and the highest luminance of 4844 cd m−2. Besides, the red/green/blue (R/G/B) monolithic tandem WPeLED shows a standard white International Commission on Illumination coordinate of (0.33, 0.33) and achieves an extremely wide color gamut reaching National Television Standards Committee of 130%. This study is the first to realize the standard R/G/B co‐electroluminescence in a monolithic perovskite device and offers a feasible strategy for developing wide‐color gamut perovskite displays.

Integrating geospatial information in the analysis of network disruptions

Disruptions in airline operations are common, especially during extreme weather events, such as hurricanes. These phenomena can and do interrupt smooth and efficient passenger transportation, and severely affect and halt airline operations. Airport network topology plays a crucial role in the development of tools to implement efficient and effective recovery actions for different stakeholders during a disruption. Hence, in this research, we propose a graph theoretical approach that studies the flight/airport network from a topology perspective, but that also incorporates a geospatial component. In our approach, we present two mathematical frameworks to help classify airports in an airport network from two perspectives: their extent of getting disrupted and being a subject to the effect of disruption. We employ simple paths of certain lengths in three different ways to reveal the weather-related impact based on airport position as a direct destination, an intermediate connection, or due to its geographical location in relation to the extreme weather event. Additionally, we develop a rerouting method to identify potential airports for redirecting passengers from a hurricane impacted airport. The computational results show the significance of incorporating geospatial element in identifying the most affected airports during a weather disruption. Moreover, our experimental analysis shows that the forecast track of a hurricane and its impact distance affect the airport network disruption. All of our codes and data are publicly available at https://github.com/harshithameda/AnalysisNetworkDisruptions.

An intelligent base link recovery management and path stability in clustered randomly distributed mobile ad hoc networks

MANETs are networks of mobile nodes that are randomly distributed and play a major role in data transmission, route discovery, and route maintenance. Connection recovery and path stability are significant issues in the MANET, making data transfer problematic. When mobile nodes move out of range or when the node lacks adequate energy to maintain connection or path stability, data packet loss happens. We suggest a Clustered Intermediate System-Clustered Intermediate System Local Connection Failure Recovery Algorithm (Clustered Intermediate System-Clustered Intermediate System LLFRA) routing migration technique that builds the node while simultaneously repairing the broken link. Also utilised to look at node energy, energy- drained nodes, and route stability is Dolphin Partner Optimisation (DPO). The suggested approach's primary goal is to guarantee route stability while reducing packet loss. The suggested method is put to the test using the NS-2 simulator. The proposed recovery protocol beats the current technique in charge of PDR, end to end delay, throughput and node failures, according to experimental outputs.

Recent Progresses in Solution-Processed Tandem Organic and Quantum Dots Light-Emitting Diodes

Solution processes have promising advantages of low manufacturing cost and large-scale production, potentially applied for the fabrication of organic and quantum dot light-emitting diodes (OLEDs and QLEDs). To meet the expected lifespan of OLEDs/QLEDs in practical display and lighting applications, tandem architecture by connecting multiple light-emitting units (LEUs) through a feasible intermediate connection layer (ICL) is preferred. However, the combination of tandem architecture with solution processes is still limited by the choices of obtainable ICLs due to the unsettled challenges, such as orthogonal solubility, surface wettability, interfacial corrosion, and charge injection. This review focuses on the recent progresses of solution-processed tandem OLEDs and tandem QLEDs, covers the design and fabrication of various ICLs by solution process, and provides suggestions on the future challenges of corresponding materials and devices, which are anticipated to stimulate the exploitation of the emerging light technologies.

Intelligent health indicator construction for prognostics of composite structures utilizing a semi-supervised deep neural network and SHM data

A health indicator (HI) is a valuable index demonstrating the health level of an engineering system or structure, which is a direct intermediate connection between raw signals collected by structural health monitoring (SHM) methods and prognostic models for remaining useful life estimation. An appropriate HI should conform to prognostic criteria, i.e., monotonicity, trendability, and prognosability, that are commonly utilized to measure the HI’s quality. However, constructing such a HI is challenging, particularly for composite structures due to their vulnerability to complex damage scenarios. Data-driven models and deep learning are powerful mathematical tools that can be employed to achieve this purpose. Yet the availability of a large dataset with labels plays a crucial role in these fields, and the data collected by SHM methods can only be labeled after the structure fails. In this respect, semi-supervised learning can incorporate unlabeled data monitored from structures that have not yet failed. In the present work, a semi-supervised deep neural network is proposed to construct HI by SHM data fusion. For the first time, the prognostic criteria are used as targets of the network rather than employing them only as a measurement tool of HI’s quality. In this regard, the acoustic emission method was used to monitor composite panels during fatigue loading, and extracted features were used to construct an intelligent HI. Finally, the proposed roadmap is evaluated by the holdout method, which shows a 77.3% improvement in the HI’s quality, and the leave-one-out cross-validation method, which indicates the generalized model has at least an 81.77% score on the prognostic criteria. This study demonstrates that even when the true HI labels are unknown but the qualified HI pattern (according to the prognostic criteria) can be recognized, a model can still be built that provides HIs aligning with the desired degradation behavior.

Parallel strips coupled split ring resonators for a desktop wireless charging system overcoming irregular route restrictions

In order to achieve efficient long-distance wireless charging and avoid the influence of irregularity of the transmission path, a desktop wireless power transmission (DWPT) implementation method based on parallel-strips-coupled split ring resonators (PSSRR) was proposed in this paper. In the DWPT system, the power was transmitted from the transmitting coil (Tx) to the receiving coil (Rx) through the magnetic resonance coupling and guiding of the PSSRR. The PSSRR consisted of two split ring resonators (SRRs), the dielectric disk above each SRR and two parallel conductor strips for the SRRs’ connection. The SRR and the dielectric disk can realize effective mutual conversion between magnetic field and propagating mode through near field magnetic resonance coupling. The parallel conductor strips were applied to achieve efficient power transmission in the first-ordered mode. The transmission characteristics of the DWPT systems with coplanar or non-coplanar bent paths were analyzed. The simulated and experimental results verified the feasibility and robustness of the DWPT system. Under the plane bent path, the transmission efficiency of the proposed DWPT system can reach 76 % at a transmission distance of 1900 mm. The proposed method provided a solution for long distance WPT through required irregular path or multi-path. The system still had the problem that partial intermediate connection was needed and surrounding metal or high permittivity materials affected the transmission characteristics. Further research can be carried out from these two aspects.

Study on amino-directed modification of oil sludge-derived carbon and its adsorption behavior of bisphenol A in water

In order to remove bisphenol A (BPA) in wastewater, this paper reported an amino-functionalized oily sludge-derived carbon (GP-H-OSC) obtained by grafting amino groups using oily sludge as a precursor, which could quickly adsorb BPA in the wastewater. The adsorption results showed that the grafting modification method was more likely to form effective adsorption sites on the surface than the impregnation modification. FT-IR and Boehm titration results indicated that the oxidation modification strategy was beneficial in generating more carboxyl groups on the surface of the oily sludge-derived carbon, which could provide intermediate connection groups for the subsequent grafting. The SEM and BET results revealed that the polyethyleneimine (PEI) would form a dense mesoporous structure on the surface during the grafting process, which was conducive to the transport of pollutants. The adsorption process of BPA by GP-H-OSC conformed to the pseudo-second-order kinetic model and the Langmuir isotherm model. The maximum extent of BPA adsorption was 393.2 mg/g based on the Langmuir isotherm model. Based on the analysis of FT-IR and XPS, GP-H-OSC mainly trapped BPA in water through the formation of hydrogen bonds between the functional amino groups on the surface and the hydroxyl groups on BPA. Moreover, primary amines were more likely to form hydrogen bonds with hydroxyl groups on BPA than imines. The removal rate of GP-H-OSC for low concentration BPA wastewater could reach 95% within 1 h, and it still had strong adsorption performance after recycling experiments. In summary, it was feasible to graft PEI on the surface of sludge-derived carbon, and the obtained amino-functionalized carbon material could adsorb BPA quickly and efficiently, showing great potential in practical wastewater treatment.