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This paper addresses the significant challenges faced by distribution system operators (DSOs) in competitive electricity markets due to uncertainties arising from electricity markets, electric vehicles (EVs), and conventional loads. To tackle these challenges, this paper proposes a pseudo-local reserve market between the DSO and EVs, which enables the DSO to integrate EV flexibility into the overall market framework while compensating for deviations in the conventional load across the wholesale electricity market. Furthermore, a two-stage framework is developed to facilitate the participation of EVs in electricity markets. In the first stage, the reserve capacity of EVs is integrated into the decision-making process for day-ahead bidding, taking into account uncertainties of the load and electricity. In the second stage, the day-ahead results are coordinated to enable the efficient dispatch of EVs for real-time market participation. To assess the efficacy of the proposed framework, a case study is conducted within a 31-node distribution system situated on a university campus located in Guangdong, China. This paper investigates the economic impact of load deviation constraints on EV reserves, revealing a penalty reduction of 3100 CNY for a daily reservation of 1000 EVs and a net profit increase of 1300 CNY for DSOs utilizing reserves. It further introduces a method for quantifying reserve capacity, enhancing DSO decision-making accuracy. • A pseudo-local reserve market is established considering EV's reserve potential. • Optimal bidding strategy for DSO in China's electricity markets is constructed. • A framework for EV coordinated V2G operation is developed. • The proposed method can limit load deviation cost for more profits. [ABSTRACT FROM AUTHOR]

Permeable cell models have contributed much to the progress in mitochondrial research. Optimization of permeabilization is required to make the cell's plasma membrane permeable to small molecules while keeping the intracellular organelles and their membranes intact and fully functional. Here we report our assessment and optimization of commonly used permeabilizing agents including different saponin preparations, digitonin, and recombinant perfringolysin O employing a new electron flow based mitochondrial assay technology that utilizes a colorimetric redox dye. The results of this study provide guidance in optimizing the conditions for mitochondrial function assays with permeabilized cells using the novel redox dye-based format. [Display omitted] • Optimization of permeabilizing agents for permeable cells. • New electron flow and redox dye-based mitochondrial function assay. • Mitochondrial energy metabolism and specific inhibition probing. • Multi-substrate format, simultaneously, automatically, and kinetically. [ABSTRACT FROM AUTHOR]

• A cost-effective and high-efficient shared fast charging scheme is proposed. • The enabled DC power is used to supply the terminal charging points. • More EV penetration is to be achieved in old residential communities. • The DC power supply achieves a 1.3 % average transfer efficiency improvement. Charging infrastructures are being deployed widely in urban and rural areas to solve the so-called "last one-kilometer" charging problem. However, for old residential communities, the existing difficult-to-charge issue is not easily solved solely by the widespread deployment of charging infrastructure owing to limited spaces, complex reconstruction, and huge costs. In this context, this paper introduces a cost-effective and high-efficient shared fast charging scheme for old residential communities. The comprised registration-based queuing charging mechanism is proposed to schedule electric vehicle (EV) charging. An integrated and multi-stage power electronic device called smart interlinking unit (SIU) is introduced for grid reconstruction. The SIU-based charging station architecture features flexible control capability, enabling DC power supply for terminal EV chargers. For this architecture, a novel hierarchical coordinated operation strategy is designed, comprising the upper-level real-time vehicle-to-grid (V2G) dispatching and lower-level coordination strategies. Case studies demonstrate that the proposed scheme could accommodate 40 % EV penetration, while exhibiting a significant decline in system investment and occupied area compared to the slow charging scheme. Additionally, a 1.3 % improvement in average transfer efficiency is verified under this architecture. The proposed strategy is proven to realize a prominent power peak-shaving and valley-filling, effective transformer load balance, and DC voltage restoration. [ABSTRACT FROM AUTHOR]

This paper proposes a novel management scheme, namely, the distribution system operator (DSO) as a key player participating in China's electricity markets owing to its high value-added capability, high customer loyalty and robust risk resistance. In light of this, this paper discusses the maximal marginal revenue for DSO in uncertain electricity markets with vehicle-to-grid operation incorporated. Initially, considering different benefit expectations of electric vehicles (EVs) owners, DSO could provide preferential contracts, including the discount price contract (DPC) and revenue-sharing contract (RSC), in exchange for the management rights of EVs. Then, the stochastic optimization model considering the spatiotemporal uncertainties of EVs and electricity markets is built up, and the optimal bidding and coordinating strategy are proposed to maximize the marginal revenue of DSO. Comprehensive case studies are conducted in a 31-node distribution system of a university campus under the electricity markets in Guangdong, China. Results reveal that different distribution of EVs parking lots has a significant impact on the profit of DSO, and the revenue for DSO is 13,477 yuan more than that for EVA by scheduling 1400 EVs' charging/discharging behavior properly. Additionally, the DSO with RSCs is exposed to 25% less market volatility risk than that with DPCs. • Comparing EV aggregator(EVA) and distribution system operator(DSO) characteristics. • Discount price contracts and revenue-sharing contracts are compared. • The advantages of DSO over EVA in market participation are analyzed. [ABSTRACT FROM AUTHOR]

• An easy-to-implement hybrid microgrid reconstruction scheme is proposed for old residential communities. • The existing transformers and power lines could be reused in the proposed hybrid microgrid architecture. • A significant maximum 297% of EV penetration could be obtained with the proposed architecture and operation strategy. • Real-time voltage regulation, desirable operation efficiency, and improved load ratio are to be implemented. The widespread popularity of electric vehicles (EVs) imposes great challenges for distribution grids, such as feeder congestion, voltage deviation, and so forth. Although building new electrical facilities is feasible to release more capacity for EV integration, this is not a wise scheme to be applied in old residential communities owing to huge costs and limited spaces. In light of this, the paper proposes an easy-to-implement and cost-effective hybrid AC/DC microgrid reconstruction scheme for low-voltage distribution grids of old residential communities. The advanced power electronic device called smart interlinking unit (SIU) is incorporated in prior power distribution rooms of residential communities, featuring integrated structure, dedicated interfaces, and flexible control capability. The SIU-based architecture reuses existing redundant transformers and power lines to form AC/DC subgrids. An outstanding transfer capacity improvement and power loss reduction via the DC renovation are quantified. Considering the varied efficiency characteristics of multiple power converters and transformers, a hierarchical coordinated operation strategy is proposed for this architecture to realize the overall energy-saving operation. The optimal operation point tracking and AC/DC voltage regulation are included in the strategy design. Regarding the target scenario in the case study, the adopted reconstruction scheme would achieve a significant 297% of the maximum EV penetration. The real-time voltage regulation for AC and DC feeders is also realized to avoid possible voltage violations. Additionally, the proposed architecture and operation strategy could obtain about 10% of load ratio improvement and 1.5% of average efficiency promotion compared to the traditional AC architecture. [ABSTRACT FROM AUTHOR]

The (Fe 1- x Dy x ) 3 C@C composites were produced by a simple sol-gel route. The structure, composition, morphology and magnetism of the composites are studied by many characterization methods, for example, X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning and transmission electron microscopy (SEM, TEM) as well as vibrating sample magnetometer (VSM). Analysis of the above results indicates that the (Fe 1- x Dy x ) 3 C is embedded in carbon nanotubes and carbon matrix and displays ferromagnetic properties. Moreover, this indicates that saturation magnetization ( M S ) values of the composites tend to increase with the increase in Dy doping. More importantly, we investigates the electrochemical hydrogen production capacity of the (Fe 1- x Dy x ) 3 C@C composites. [ABSTRACT FROM AUTHOR]

As the number of electric vehicles (EVs) surges, EVs are expected to supply auxiliary services for power grid through the vehicle-to-grid (V2G) operation. Specifically, vehicle-to-vehicle (V2V), as a beneficial supplement of V2G, has received increasing attention owing to the capability for flexible EVs deployment and profitable individual interaction. In this paper, a genuine V2V market mechanism aiming for maximum revenue of each EV owner is proposed to construct a distributed electricity market. It reveals the dominance of EV owners from the perspective of market and allows the trade among EV owners in local distribution grid with charging points such as charging stations and auto parks. To this end, the implementation of V2V market mechanism is analyzed in detail, including the electricity price, the process and the integration with the internet of smart charging points (ISCP), a cyber-physical architecture. Then, EVs' energy dispatching is formulated via the non-cooperative game model, in which each EV owner anticipates maximizing individual revenue by choosing feasible strategies. The existence and uniqueness of Nash Equilibrium (NE) in a non-cooperative game is proved by means of variation inequality (VI) theory. Finally, the ISCP-based optimal algorithm is developed to solve the NE efficiently, thereby maximizing reward of each EV owner. Comprehensive case studies show that the proposed V2V market mechanism can implement distributed dealing among EV owners with reducing individual charging cost and regional load variance effectively. Specially, the costs of EV1, EV8 and EV9 decrease by 31%, 36% and 34%, respectively. And V2V charging demonstrates much lower variance (10.5209) than regular charging (14.1124). Additionally, the convergence of the algorithm is also demonstrated, reaching the NE in less than 30 iterations for each EV. • A genuine V2V market mechanism considering the dominance of EV owners is proposed. • The integration of V2V market mechanism and cyber-physical architecture is executed. • A non-cooperative game model and corresponding algorithm are adopted to solve the NE. • Revenue and load variance in EVs and convergence of the algorithm are analyzed. [ABSTRACT FROM AUTHOR]

• A novel carbon emission reduction(CER) methodology is proposed. • The Black-Scholes mode is introduced to measure carbon emission option pricing. • Case studies of campus grid CER assessment are conducted in Shenzhen. • Methods and policy suggestions of CER are given for grid integration of EVs. China, as the world's largest emitter of carbon emissions, has implemented carbon markets to reduce carbon emissions, but the economic feasibility of integrating electric vehicles (EVs) into these markets remains uncertain. To address this challenge, we propose a novel methodology for grid integration of EVs based on the Shenzhen carbon inclusive management measures. Our proposed methodology can optimize EV charging schedules based on carbon emission prices and improve the economic feasibility of low-carbon transitions through EVs in China. We incorporate the Black-Scholes model to measure carbon emission option pricing and develop an optimal bidding strategy that considers spatiotemporal uncertainties of EVs and electricity markets. We use numerical simulations with real-world data from Shenzhen carbon emission market and Guangdong electricity market to demonstrate the effectiveness of our proposed methodology. Results reveal that scheduling 100 EVs' charging/discharging behavior properly can generate a revenue of 2379.4 yuan for the distribution system operator, while the revenue for carbon emission reduction (CER) is only 9.35 yuan. This paper demonstrates that the potential revenue of CER may be substantially based on the future scenario for the carbon emission market. These findings provide valuable insights for policymakers and stakeholders seeking to reduce carbon emissions in China's electricity sector. [ABSTRACT FROM AUTHOR]

The superior piezo-photocatalytic performances of KNbO 3 -based materials were achieved by the enhanced photo-induced carrier separation and migration based on the effective strategies of heterojunction construction and polarization engineering. A KNbO 3 /WO 3 type-II heterojunction was fabricated by an impregnation-calcination method, and its outstanding piezo-photocatalytic performance was demonstrated. Compared to individual KNbO 3 and WO 3 , KNbO 3 /WO 3 composites exhibited better degradation performance for RhB solution under visible light irradiation, and the degradation rate of 30%KNbO 3 /WO 3 composite for RhB solution was 98% within 80 min (its reaction rate constant k was 0.03894 min−1). Inspiringly, the polarized 30%KNbO 3 /WO 3 composite degraded RhB solution completely within 60 min under visible light irradiation with auxiliary ultrasonic activation, and its reaction rate constant was up to 0.0612 min−1 (3.35 times that of individual KNbO 3). The synergistic effects of heterojunction construction, polarization engineering, and ultrasonic vibration in KNbO 3 /WO 3 composite were confirmed, and the multi-electric fields in polarized KNbO 3 /WO 3 heterojunction significantly enhanced carrier separation, thus promoting piezo-photocatalysis. This work proposes an important strategy for designing multi-electric field-driven ferroelectric-based heterojunction photocatalysts. [Display omitted] • KNbO 3 /WO 3 type-II heterojunction photocatalyst has been successfully designed. • Superior photocatalytic performance was further enhanced by polarization engineering. • A multi-field-driven ferroelectric-based heterojunction photocatalyst was achieved. [ABSTRACT FROM AUTHOR]

A central challenge in large scale sustainable hydrogen production by electrolyzing water is to develop efficient and economical electocatalysts with nanostructural materials. This work herein reports the facile solvothermal synthesis of MoS 2 /Co 3 S 4 hollow nanostructural co-catalyst with high activity and stability for electrochemical hydrogen evolution reaction (HER) by compositing cheap and HER-active MoS 2 on Co 3 S 4 HER catalyst. By morphology and structure modulations, this high-quality nanostructure, which is confirmed by several characterizing techniques, can be considered as excellent catalyst to split water into H 2 in a wide pH range via the electric drive. Corresponding electrochemical measurement results of 55.6 mV dec −1 and 115.3 mV dec −1 Tafel slope in acid (pH = 0.3) and alkaline (pH = 14) media demonstrates our predictions. We believe that such performance improvement is mainly due to the much increased active sites for catalysis because of composition process and hollow structure. These findings open up an effective and propagable strategy for nanostructural HER catalysts synthesis. [ABSTRACT FROM AUTHOR]

Magnetostrictive actuators invariably exhibit bias-rate-dependent hysteresis, which could cause vibration and error in the micro-positioning control. We present a methodology for linearization control for the hysteresis of a magnetostrictive actuator with a wide range of input rates and biases. The hysteresis compensation is attained through application of a dynamic Bouc-Wen model and experimental measured hysteresis properties of the magnetostrictive actuator under inputs with different frequencies and biases. The effectiveness of the compensator for hysteresis is demonstrated through experimental results of the magnetostrictive actuator under inputs at different frequencies and bias levels. Based on the proposed compensator, a displacement PID controller is applied to force the output displacement of the magnetostrictive actuator to track the desired displacement accurately thereafter. The maximum absolute tracking errors is 0.052 μm. Compared to the control results without the compensator, the compensator can reduce the control error by about 85%. The results indicate that this study provides an effective method which can compensate the hysteresis of the magnetostrictive actuator under different frequencies and biases of inputs. [ABSTRACT FROM AUTHOR]

Ce 3+ and Tb 3+ ion co-doped aluminum nitride (AlN) phosphors were prepared by a simple solid-state reaction. X-ray diffraction (XRD), high resolution transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), as well as photoluminescence (PL) spectra were employed to analyze the samples. The crystal structure, morphology, photoluminescence properties and the energy transfer process of Ce 3+ and Tb 3+ ion co-doped AlN phosphors were carefully investigated. An enhanced light emission and red-shifted excitation wavelength can be observed in AlN:Tb phosphors after co-doped with Ce 3+ ion. The results indicate that the Ce 3+ and Tb 3+ ion co-doped AlN phosphors can be effectively used in fingerprint identification. The phosphor-marked fingerprints on various substrates can be clearly manifested with good contrast and weak background inference, holding significant applications in the forensic field. [ABSTRACT FROM AUTHOR]

The Fe 3 C nanoparticles were synthesized via a facile synthesis method. The structures, morphology and magnetic properties were investigated by X-ray diffraction, Raman spectra, X-ray photoelectron spectroscopy, transmission electron microscopy and vibrating sample magnetometer. It was found that the prepared nanoparticles possess the admirable magnetic moment, approaching to the theoretical value. More importantly, we briefly propose the synthesis mechanism. This simple and general approach provides a novel way to synthesize metal carbide. [ABSTRACT FROM AUTHOR]

Low light extraction efficiency (LEE) is a key challenge of chip-on board (COB) packaging light-emitting diodes (LEDs). In this paper, a facile preparation of micro-lens array was proposed based on the ion wind patterning. The geometries and sizes of the micro-lens arrays were controlled through adjusting the voltage parameter of the ion wind generation. Consequently, the micro-lens array with the diameter of 180 µm and the gap distance of 15 µm has been fabricated. Benefitting from this micro-lens array, the LEE of COB packaging LEDs was enhanced by 9%. This facile fabrication of micro-lens array would be a promising method to improve the LEE of COB packaging LEDs. [ABSTRACT FROM AUTHOR]

Alteration of hydrological regime due to diversion-type hydropower station has significant impacts on the fish habitat in the de-watered river channel.This paper evaluate the alteration of hydrological regime by using the Indicators of Hydrologic Alteration (IHA) and the Range of Variability Analysis (RVA),analysis the impact on the fish habitat.The IHA&RVA analysis suggests that the construction of diversion-type hydropower hydrological seriously effectshydrological alterations of downstream and damages the fish habitat. Instream flow and hydrogragh study should be developed urgently. [ABSTRACT FROM AUTHOR]

Abstract: Large vertical cylindrical steel tanks constructed on soft foundations may bring forth various types of settlement, which is well known as the uniform settlement, the planar tilt and the differential settlement. Measured settlements of steel tanks in several practical projects are first summarized according to the in-site surveying data, and two kinds of settlement patterns are clearly defined, which are referred to as the global differential settlement and the localized differential settlement. Two practical floating-roof steel tanks are taken as the illustrative examples of large steel tanks, which are marked TK-2020 with the height-to-radius ratio of 0.35 as the representatives of large volume tanks and TK-2090 with the height-to-radius ratio of 0.7 as representatives of smaller volume tanks in this paper. Buckling behaviors of the two illustrative tanks under the global and localized differential settlement are investigated using the general-purpose finite element computer package ABAQUS by means of the geometrical nonlinearity algorithm. It is shown that for tanks under global differential settlement, local buckling occurs first at the eave wind girder, followed by a stable post-buckling behavior, so that the local buckling of the wind girder can be taken as the serviceability limit state and the post-buckling strength can be utilized in structural design of tanks. Moreover, the behavior of tanks under localized differential settlement is related to the degree of localization. The buckling behavior in the case of a large circumferential central angle for localized settlement is similar to that under global differential settlement, while the effect of the localized settlement with a relatively small central angle is more obvious than that of the global differential settlement, and the snap-through buckling induced by localized settlement would govern the design. [Copyright &y& Elsevier]

Abstract: In present research, Barker-coded excitation is applied to improve the sensitivity of emboli detection in transcranial Doppler (TCD) ultrasound systems. A 13-chip Barker code with a base pulse sequence that comprises two cycles at 2 MHz is used to compare with a 20-cycle pulse in both simulation studies and in vitro experiments. The results show that the system using coded excitation gains a 2.78-dB improvement in measured embolus-to-blood ratio (MEBR) while keeping a similar signal-to-noise ratio (SNR). The simulation results also indicate that the MEBR of the emboli are related to their velocities—a fast embolus has lower MEBR compared with a slow one with the same backscatter amplitudes, which makes fast emboli more difficult to detect. TCD system using coded excitation is more sensitive for faster and smaller emboli, which is significant for early diagnosis of stroke. (E-mail: xianglei00@mails.tsinghua.edu.cn) [Copyright &y& Elsevier]

• Climate-sensitive additive stand biomass models were developed. • The difference in biomass estimations when using the new models at a large scale was quantified. • Forecast combination method reduced the uncertainty from the biomass models. • About $8.3 million carbon services were underestimated using traditional models. • Climate-sensitive stand biomass models were recommended for carbon service accounting. Accurate forest carbon service accounting is essential for climate change mitigation. At present, the knowledge about whether and how climate-sensitive stand biomass models could reduce the uncertainty of forest biomass/carbon estimation is lacking. Hence, the aim of this study is to develop climate-sensitive stand biomass models and quantify their differences. Data containing 539 sample plots of larch plantations in northern and northeastern China were utilized to develop two basic and the corresponding climate-sensitive stand biomass models. Owing to the uncertainty from predictors, the forecast combination method was used to combine the two basic models (FCMs) and the two climate-sensitive models (CS-FCMs) and to quantify the difference in biomass estimations at the plot and regional scales. Results showed that the adjusted R 2 values of the stand biomass models were greater than 0.85 and the relative root mean square errors ranged from 5.51% to 22.62%. The CS-FCMs produced more accurate biomass estimates than the FCMs. The difference in biomass estimations derived from biomass models with and without climatic variables was 411,549 tons or 0.27% at the regional scale, but the carbon value difference amounted to about $8.3 million. This study underlined the importance of accurate carbon accounting based on climate-modified stand biomass models for forest carbon management. [ABSTRACT FROM AUTHOR]

The nicotinamide adenine dinucleotide derivatives (NADPH, NADP+, NADH, and NAD+) are important redox cofactors that involve in many biological activities, and their concentration levels are associated with a variety of diseases. In this work, an imidazolium functionalized polydiacetylenes sensing system (IM-PDAs) is reported to selectively detect the reduced form of nicotinamide adenine dinucleotide phosphate (NADPH). Depending on the electrostatic attraction between the positively charged imidazolium heads and the negatively charged phosphate groups, the sensing system exhibits colorimetric and fluorescent responses when exposed to NADPH and its oxidized form (NADP+); while the system does not respond to the less negatively charged NADH and NAD+ at the concentration range tested in this study. Owing to the positively charged nicotinamide of NADP+, the detection sensitivity of IM-PDAs towards NADP+ is much lower than that towards NADPH, successfully differentiating NADPH from the rest three cofactors. Furthermore, IM-PDAs loaded paper-based sensor is constructed and demonstrates the potentials of IM-PDAs based sensing device for practical applications in NADPH detection. Image 1 • A polydiacetylenes-based sensing system was constructed for selective detection of NADPH. • The sensing system owns an ultralow detection limit of 23.5 nM towards NADPH. • The paper-based PDAs sensing device also demonstrated the ability of selectively detecting NADPH. [ABSTRACT FROM AUTHOR]

• The Fe 3 N nanoparticles were successfully synthesized by a simple urea route. • The prepared Fe 3 N nanoparticles have regular spherical shape and uniform particle size. • Research on magnetic properties points out that the prepared nanoparticles possess relatively highe coercivity (604.4 Oe). • Through the study on surface properties of prepared materials, we analyzed the reasons for the change of coercivity. The ε-Fe 3 N nanoparticles/C composite materials have been synthesized by ethylenediamine nitrided urea complexing precursors. The prepared ε-Fe 3 N NPs have regular spherical shape and small particle size. And the prepared ε-Fe 3 N NPs/C magnetic materials have significantly higher coercivity (604.4 Oe) and relatively lower saturation magnetization (21.1 emu/g) compared with the reported experimental and theoretical studies of ε-Fe 3 N. We consider that the surface properties and particle size of the prepared materials will result in the changes in magnetic properties. [ABSTRACT FROM AUTHOR]

• Parametric analysis and optimization of the dimpled tubes are carried out. • Regression model is acquired and ANOVA is performed to identify significant factors. • Interactive effects are extraordinarily significant and complex. • Optimized dimpled tube are obtained to achieve best PEC by desirability approach. In this paper, parametric study and optimization of dimpled tubes based on Response Surface Methodology and desirability approach were carried out. The diameter of dimples, the ratio of the depth and the diameter, the ratio of the spacing between two axially adjacent dimples and the diameter, and the quantity of dimples in a transverse cross-section of dimpled tubes were chosen as the design parameters. And the dimensionless characteristic parameters of heat transfer and resistance: Nu / Nu s and (f / f s)1/3 were adopted as responses. Firstly, a numerical model of dimpled tubes with polyhedral mesh based on Star-CCM+ 12 was established and verified by comparing with experimental results. Secondly, the modified quadratic regression and the modified two-factor interaction (2FI) model were obtained after conducting the analysis of variance (ANOVA) and the interactive effects of four geometrical parameters on Nu / Nu s and (f / f s)1/3 were discussed. The results show that interactive effects among the four geometrical parameters are significant and complicated because one factor affects the impact of another factor on Nu / Nu s and (f / f s)1/3. Eventually, optimized parameters are obtained using the desirability approach with the goal of maximum Nu / Nu s and minimum (f / f s)1/3. [ABSTRACT FROM AUTHOR]

Low remnant polarization and high coercive field are the main factors limiting the practical application of Ca 3 Ti 2 O 7 -based hybrid improper ferroelectric ceramics. Based on sol-gel method and soft doping effect, (Ca 1- x Nd x) 3 Ti 2 O 7 (x= 0.003) ceramics with higher remnant polarization of ∼3.53 μC/cm2 and lower coercive field of ∼91 kV/cm were obtained. More interestingly, thanks to the large distortion amplitude of TiO 6 octahedron and effective suppression of defects such as oxygen vacancies caused by Nd3+ as a donor dopant, the remnant polarization of (Ca 1- x Nd x) 3 Ti 2 O 7 (x = 0.003 and 0.006) ceramics measured at 10 Hz using the DHM mode were as high as 7.33 μC/cm2 and 5.85 μC/cm2. These findings prove that the soft doping at A sites of Ca 3 Ti 2 O 7 material is a simple and effective strategy to enhance its hybrid improper ferroelectricity. [ABSTRACT FROM AUTHOR]

Ca 3 (Ti 1- x Co x) 2 O 7 ceramics were prepared by a tartaric acid sol-gel method and sintered in an oxygen atmosphere. The introduction of Co2+/Co3+ as acceptor dopants leads to the formation of more oxygen vacancies and defect dipoles in Ca 3 (Ti 1- x Co x) 2 O 7 ceramics. Oxygen vacancy and defect dipoles lead to the transition of dielectric, leakage, and ferroelectric behaviors of Ca 3 (Ti 1- x Co x) 2 O 7 ceramics. The coexistence of hybrid improper ferroelectricity and ferromagnetism at room temperature in Ca 3 (Ti 1- x Co x) 2 O 7 ceramics has been successfully realized through the superexchange interaction of Co–O–Co. Ca 3 (Ti 1- x Co x) 2 O 7 ceramics exhibit superior ferroelectricity (the remnant polarization is 3.29 μC/cm2) and enhanced ferromagnetism (the remnant magnetization reaches 6.4×10−3 emu/g). This strategy based on the introduction of transition metal ions with unfilled 3d shells at B sites is an important approach to realize novel room-temperature single-phase multiferroic materials for Ca 3 Ti 2 O 7 -based materials. [ABSTRACT FROM AUTHOR]

• Multi-scale average processing for data expansion is proposed. • An end-to-end multi-branch network for bearing fault diagnosis is designed. • Using the reconstructed signals as complementary input of neural network. • Improve the transferability and adaptability with proper transfer learning strategy. Conventional intelligent bearings fault diagnosis methods generally extract fault features with a single channel, which seriously limit the features richness and the diagnostic accuracy. A novel end-to-end diagnosis framework which incorporate multi-scale average processing into the multi-branch convolutional neural network (MBCNN) is established here, thus rich and complementary fault features can be captured from the multi-scale reconstructed signals via multiple parallel residual CNN branches. Besides, with the help of a fine-tuning based transfer learning strategy, the well-trained model on source domain is competent to the related diagnostic tasks of bearings under diverse working conditions and devices. Comparative experiments under 3 cases are conducted, and the results show our approach can be provided with more excellent performances and superior transferability compared with the state-of-the-art ones. For instance, the transfer diagnostic accuracies of MBCNN exceed 98.56% and 98.38% under diverse working conditions and cross-devices, respectively. [ABSTRACT FROM AUTHOR]