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A seepage testing system was designed and a series of seepage experiments on broken rock was conducted using different original porosity conditions and clay contents. The mass-loss process of the broken rock and the change in water flow velocity were investigated. After the mass-loss test, the non-Darcy seepage characteristics of the broken rock were tested through a step-by-step pressure-reduced seepage test. The experimental results show that the mass-loss and water velocity evolution during the water inrush could be divided into four stages: acceleration, stable with slight fluctuations, reacceleration, and stable. The lost-mass and change in water velocity were positively correlated with the clay contents and negatively correlated with the original porosity. By introducing the evolution equation of the Kozeny-Carman equation and the liquid limit index which characterises the effective particle size, the prediction model of the permeability coefficient was built. Six prediction models of the non-Darcy coefficient were verified against the testing results. The prediction model of the critical flow velocity from a Darcy flow to a non-Darcy flow using the Forchheimer number was also established. The results could provide an important reference for understanding water inrush mechanisms, adopting effective control measures for water inrush events, and calculating the water influx of tunnels.

The high throwing power (TP) value is one of the most important parameters for the Cu electroplating of through-holes in flexible printed circuit (FPC). It was found that an ultra-high TP value could be obtained using a specific suppressor, i.e., iodonitrotetrazolium chloride (INT) in the electrolyte. The ultra-high TP value was attributed to fast-consumption of this suppressor instead of traditional convection-dependence adsorption mechanism. A consumption model was built and simulated to clarify the formation of the ∆θ, i.e., the difference of suppressor fractional coverage between the entrance and center of through-holes sidewalls. It revealed that the TP, proportional to the ∆θ, was determined by the consumption rate of a suppressor. This simulation results were well consistent with the results of electroplating using INT with different concentration. The electrochemical analysis verified the characteristics of fast consumption of INT due to the reduction reaction. The difference of residual INT between the entrance and center of the plated through-holes confirmed the occurrence of ∆θ. These results supported the opinion that the ultra-high TP value was obtained by fast-consumption mechanism of INT suppressor.

Influence of coiling temperature (CT) on the microstructure and mechanical properties of a hot-rolled high-strength steel microalloyed with Ti, Mo and V was elucidated. The precipitation behavior of nano-sized particles was investigated by theoretical calculation and quantitative analysis. And the results revealed that V-enriched (Ti, Mo, V)C precipitated in the ferrite matrix. As the CT decreased, the site fractions of Ti in (Ti, Mo, V)C changed little, the site fractions of Mo increased, and the site fractions of V decreased accordingly. Moreover, the low CT could refine the microstructure and precipitated particles but suppress the precipitation of (Ti, Mo, V)C particles simultaneously, leading to the volume fraction of (Ti, Mo, V)C significantly decreasing, consequently causing an increment of grain refinement strengthening and a reduction in precipitation hardening. When the CT was 600 °C, the steel characterized by fine polygonal ferrite, a small amount of bainite and nano-sized (Ti, Mo, V)C precipitates exhibited the optimum mechanical properties with the ultimate tensile strength of 870 MPa, yield strength of 807 MPa and elongation to fracture of 17%.

Intelligent separation is a core technology in the transformation, upgradation, and high-quality development of coal. Realising the intelligent recognition and accurate classification of coal flotation froth is a key technology of intelligent separation. At present, the coal flotation process relies on artificial recognition of froth features for adjusting the reagent dosage. However, owing to the low accuracy and subjectivity of artificial recognition, some problems arise, such as reagent wastage and unqualified product quality. Thus, this paper proposes a new froth image classification method based on the maximal-relevance-minimal-redundancy (MR MR)-semi-supervised Gaussian mixture model (SSGMM) hybrid model for recognition of reagent dosage condition in the coal flotation process. First, the features of morphology, colour, and texture are extracted, and the optimal froth image features are screened out using the maximal-relevance-minimal-redundancy (MRMR) feature selection algorithm based on class information. Second, the traditional GMM clusterer is improved, called SSGMM, by introducing a small number of marked samples, the traditional GMM’ problems of unclear training goals, invisible clustering results, and artificially judged clustering results are solved. Then a new hybrid classification model is proposed by combining the MRMR with the modified GMM (SSGMM) which can be named as (MRMR - SSGMM). The optimal froth image features are screened by MRMR to provide the SSGMM classifier. In the process of training and learning the feature samples, using the marked feature samples of froth images to guide the unmarked feature samples. The information of marked feature samples of froth images is mapped to the unmarked feature samples, the classification of the froth images were realised. Finally, the accuracy of the SSGMM classifier is used as the evaluation criterion for the screened features by MRMR. By automatically executing the entire learning process to find the best number of froth image features and the optimal image features, so that the classifier achieves the maximum classification accuracy. Experimental results show that the proposed classification method achieves the best results in accuracy and time, compared with other benchmark classification methods. Application results show that the method can provide reliable guidance for the adjustment of the reagent dosage, realize the accurate and timely control of the reagent dosage, reduce the consumption of the reagent and the incidence of production accidents, and stabilize the product quality in the coal flotation production process.

Semitransparent polymer solar cells (STPSCs) are a potential photostatic structure for building-integrated photovoltaic (BIPV) application. In order to realize the application practically, the balance between efficiency, transparency, and color property is a challenge in the field. In this paper, efficient semitransparent polymer solar cells utilizing P3HT:ICBA as active layers were demonstrated. By introducing ZnSe/LiF distributed Bragg Reflector (DBR) onto the device, the power conversion efficiency (PCE) has been increased to 6.19%. In addition, this approach can also improve the color render property by leveling the transmittance spectrum. The highest color-rendering index (CRI) is achieved using device with 1 pair of DBR. As a result, the high efficiency and fine CRI confirmed that the STPSC with DBR is an effective structure for BIPV application.

Accurate classification and recognition of coal flotation froth is one of the key technologies for intelligent coal separation. At present, the coal flotation process relies on artificial recognition of froth features for adjusting the reagent dosage, which cannot realize the optimal control of the quality of the clean coal product and the cost of the reagents. Therefore, in this paper, it is proposed a method of froth image clustering with feature semi-supervision through selection and label information. It is mainly divided into two stages: offline clustering and online recognition. The offline stage is to preprocess the froth image under various reagent conditions, extract the morphology, colour and texture features, and select the multi-dimensional optimal froth image features. A small number of marked samples are introduced to optimize the Gaussian mixture model. The selected optimal features are integrated into the optimized Gaussian mixture model to construct a froth image clusterer with multi-dimensional optimal features and class labels. In the online stage, the real-time froth image features are input clusterer and compared with the cluster feature samples to identify the current reagents conditions, which is used as feedback information to guide the abnormal reagent conditions during the production process. The effect of the amount of supervision information and the quality of feature on clustering results is analyzed and compared through experiments. The application results show that this method can provide key technical support for the accurate control of the dosage of reagents and the quality of clean coal product in the coal flotation production process, reduce the cost of reagents and the number of production accidents, improve the economic benefits, and promote the development of coal flotation intelligence to a higher level.

Coal seam mining is one of the most widely participated engineering activities in China. This study examined the failure process induced by underground thin coal seam mining of Wangxia perilous rock in Chongqing, China. Numerical simulation was conducted on the stress, displacement and plastic deformation with Fast Lagrangian Analysis of Continua 3D (FLAC3D). Results show that tensile stress is dominant and it keeps increasing during coal mining. The stability failure process experiences four stages from the perspective of crack propagation. A new simplified subsidence prediction method was proposed for quick engineering applications. The relationship between mining geometric parameters and rock mass stability was established and the ultimate mining dimensions were suggested. The simplified method was demonstrated to be reliable.

The rapid and accurate measurement of in situ stress fields is one of the essential steps in geological engineering. Indoor acoustic emission tests and the Kaiser effect provide a promising prior peak stress measurement method. This paper aims to qualitatively explore the time delay mechanism of the Kaiser effect under uniaxial compressive stress. Acoustic emission tests were conducted with natural and water-soaked sandstone specimens to examine the time delay phenomenon of the Kaiser effect, and the typical Griffith fracture mechanics theory was adopted to explain the mechanism. The time delay of the Kaiser effect under uniaxial compressive stress was affected by the friction coefficient on the crack surfaces and the initial crack angle $$\beta$$ . The time effect was indirectly induced by the changes in the friction coefficient on the crack surfaces, and the friction coefficient was controlled by the water content in the rock specimen. A higher initial friction coefficient led to an earlier and easier time delay of the Kaiser effect. Consequently, from the aspect of the Kaiser effect, it was suggested that when testing in situ stress, measures should be taken to maintain the original moisture contents in the rock cores after they are drilled underground. Otherwise, the in situ stress should be tested within 7 days.

The double-row anti-slide pile is one of the main measures for treating medium and large-scale landslides. However, the pile–soil interaction mechanism and the influence of the row spacing and the pile spacing on the interaction are not very clear in the process of the load-caused landslide evolution. Based on the interaction model test of the double-row anti-slide pile and the load-caused landslide is carried out by using transparent soil model technology. The research results show that the transparent soil technology has advantages in capturing “wave-type” distribution of the displacement isoline and studying the pile–soil interaction and the soil arching effect in the landslide. The pile–soil interaction process can be divided into three stages, the initial deformation stage, the soil arch stability stage, and the deformation stage of the soil arch. With the increase in the row spacing, the reinforcement effect of the front pile to the rear pile is weakened. With the increase in the pile spacing, the phenomenon of soil flow around piles is more likely to happen. Pile spacing has a significant effect on landslide displacement control. And when the row spacing and the pile spacing are too large, there is no soil arch stability stage in the process of the landslide evolution. The conclusion has specific guiding significance for engineering practice.

Quantum dense coding properties between two identical and spatially separated atoms in free space with different initial states is investigated. It shows that dense coding capacity χ experienced a sharp decline firstly and then gradually increased to be one steady value 1 with increasing Γt. The realization of dense coding capacity χ is found to be strongly dependent on the initial states. It is worth noting that the initial pure state |ee〉 is not useful for dense coding in this system, due to the dense coding capacity χ is always less than 1(a valid dense coding capacity satisfies χ > 1). Otherwise, for the initial entangled state and mixed state, one can obtain the valid dense coding capacity, the results show that one threshold value of tc is exists, and when t < tc the dense coding capacity is valid. Tuning the atomic distance between the two atoms slightly broaden the valid dense coding region and improve the value of tc. Decreasing the purity a of initial states not only broaden the region but also prolong the effective time where one can carry out the valid dense coding successfully.

This paper proposes an asymmetric benefit compensation model for stimulating rational agents, who often have disparate geography, hydrology, climate, and socio-economies, to participate in cooperative transboundary water management. A social planner model is initially developed to maximize the total water benefit of a river system under the assumption of perfect cooperation among the agents. Subsequently, a Stackelberg game-theoretical model is used to derive the agents’ disagreement utility based on considering their spatial heterogeneity in water accessibility. Based on the agents’ bargaining weights produced by several multi-attribute decision analysis methods, the aggregate water benefit is then redistributed among the agents by adopting the asymmetric Nash bargaining solution. The possible benefit compensation solutions are finally compared by using a composite index that can synthetically consider optimality, equity and stability criteria. The Qujiang River Basin in China is used to demonstrate the applicability of the suggested model. The results show that this integrated model can offer useful insights for conflict resolution in river sharing problems.

Seepage-induced internal erosion is observed in both artificially engineered fill structures and natural soil deposits. Fine content is of great significance for the fabric of soil. This paper aimed to determine the critical fine contents of natural soil deposits beyond which the internal stability of the mix was distinctly altered and illustrate the internal erodibility from the viewpoint of fabric. To this end, a fixed-wall permeameter capable of accurately detecting the critical hydraulic gradient of erosion initiation and collecting the cumulative eroded soil mass at a constant inflow rate was developed. Silty clay particles and sandy gravel particles extracted from original soil were employed to reconstitute specimens with fine contents ranging from 0 to 100%. Porosity measurement, seepage testing, and direct shear testing were conducted on remolded samples. Companion control specimens were tested under different flow rates to verify the applicability of the experimental device. The results indicate that according to critical fine content, the fabric of the soil samples with different fine contents could be split into coarse-particle-supported structure (CPSS), fine-particle-supported structure (FPSS), and transitional coarse–fine-particle-supported structure (TCFP). The newly developed experimental device provides a feasible methodology to investigate the internal erodibility of natural soil deposits. Different fabrics correspond to disparate shear strengths and distinct erosion characteristics, including the critical hydraulic gradient of erosion initiation, cumulative eroded soil mass, and average hydraulic conductivity. For coarse-particle-supported structure specimens, the coarse particles predominantly govern the mechanical and hydromechanical properties. An increase in fine content within pores formed by coarse particles could increase shear strength and reduce susceptibility to internal erosion. The mechanical and hydromechanical properties of FPSS specimens were basically controlled by fine particles. Coarse particles suspended in a fine matrix could somewhat increase the soil’s shear strength and reduce internal erodibility. TCFP specimens were most vulnerable to internal erosion in terms of minimum critical hydraulic shear stress and maximum cumulative eroded soil mass. It is essential to expand the scope of research to cover the transitional coarse–fine-grain-supported structure instead of remaining limited to the coarse-grain-supported structure.

Optimal dense coding of a two-qubit anisotropic Heisenberg XXZ model under decoherence is investigated with the Werner state as the initial state. With the time evolution, the dense coding capacity χ oscillates firstly, and then reaches a stable value 1 in the long time limit, whatever the values of other parameters are. Our results imply that the purity r of the initial state have a strong influence on the initial value of the optimal dense coding capacity. When the purity r of the initial state increase, the initial value of dense coding capacity increase. Besides, the coupling coefficient and Dzyaloshinski-Moriya(DM) both have strong influence on the frequency of the oscillation and the area of t that the optimal dense coding is feasible(tf). Interestingly, the decoherence rate γ can strongly affect the dense coding capacity. With the decreasing of γ, the area of tf(which will make the dense coding capacity greater than 1) becomes more wider. When γ = 0, it will still allows a valid dense coding. So we can adjust the parameters to get a optimal dense coding.

Self-enforceable and sustainable management strategies for transboundary rivers necessitate synchronously considering fairness and stability, which involves synthesizing the multidimensional nature of hydrology, environment, and socio-economy. Based on the equitable and reasonable principles of international resource distributions defined by the UN Watercourses Convention, this study proposed an integrated decision support framework by combining the multi-criteria decision making, the bankruptcy theory, and the power index with the aim of managing transboundary rivers fairly and sustainably. Subsequently, an optimization model based on this new framework was established by introducing the linear interval function to formulate the utility objective for all agents. Finally, using the Dongjiang River Basin in China to illustrate the availability of the proposed framework and optimization model. The results showed that the proposed methods could provide insights for transboundary river management through simultaneous consideration of the fairness and stability criteria.

Highlights Shape memory self-soldering tape used as conductive interconnecting material. Perfect shape and conductivity memory performance and anti-fatigue performance. Reversible strong-to-weak adhesion switched by temperature. Abstract With practical interest in the future applications of next-generation electronic devices, it is imperative to develop new conductive interconnecting materials appropriate for modern electronic devices to replace traditional rigid solder tin and silver paste of high melting temperature or corrosive solvent requirements. Herein, we design highly stretchable shape memory self-soldering conductive (SMSC) tape with reversible adhesion switched by temperature, which is composed of silver particles encapsulated by shape memory polymer. SMSC tape has perfect shape and conductivity memory property and anti-fatigue ability even under the strain of 90%. It also exhibits an initial conductivity of 2772 S cm−1 and a maximum tensile strain of ~ 100%. The maximum conductivity could be increased to 5446 S cm−1 by decreasing the strain to 17%. Meanwhile, SMSC tape can easily realize a heating induced reversible strong-to-weak adhesion transition for self-soldering circuit. The combination of stable conductivity, excellent shape memory performance, and temperature-switching reversible adhesion enables SMSC tape to serve two functions of electrode and solder simultaneously. This provides a new way for conductive interconnecting materials to meet requirements of modern electronic devices in the future.

The soil-rock mixture (S-RM) is widely used as a kind of geotechnical material in some construction engineering. When analyzing the stability of the engineering, the strength properties of S-RM are used as crucial input parameters. In this paper, to improve the understanding of strength properties of S-RM, a series of large-scale direct shear tests were conducted on S-RM with two volumetric rock block contents (VBCs), each with three types of block lithology. The particle breakage after each test and its relationship with strength properties were also analyzed. The results reveal that the influences of VBC and block lithology on particle breakage are slight when VBC is low, while significant as VBC increases. Compared with the traditional M-C strength criterion, a modified M-C nonlinear strength criterion is more suitable for the S-RM. When VBC is low, the influences of VBC and block lithology on the strength properties are slight. However, when VBC is high, their impacts will become greater, especially on the nonlinear strength parameter Δφ. The nonlinear strength characteristics become more obvious with an increase in relative breakage index Br, which are mainly caused by the particle breakage during the shearing process.

A new 1,2-seco-furan-coumarin, claulancoumarin A (1), and a known 1,2-seco-coumarin, (Z)-2,4-dihydroxycinnamic acid (2), were isolated from the branches and leaves of Clausena lansium. Their structures were elucidated by spectroscopic analysis, including NMR and MS.

The corresponding relationship between the fracture geometrical morphology of laminar shale and the acoustic emission (AE) power spectrum characteristics was established to further reveal the shale microdamage mechanism. Laboratory Brazilian tests coupled with AE and digital image correlation (DIC) were conducted on black shale disks. The amplitude–time–dominant/second dominant frequency values of AE waveforms from the entire loading process were extracted with the function package PSD in MATLAB. The geometrical morphology of shale disk fracture is the result of a dynamic balance of microcracks, spatial anisotropy, local heterogeneity of the shale specimen, and the stress condition. There is a corresponding relationship between the distribution of dominant/second dominant frequency and shale internal microdamage. Four factors contribute to the shale specimen final failure, including the tearing of the shale matrix induced by local tensile failure (high dominant/second dominant frequency components at approximately 300 kHz), shearing on the bedding layer (middle dominant/second dominant frequency components at approximately 200–250 kHz), opening of the bedding layer induced by the weak structural plane, and friction on the microcrack surface (low dominant/second dominant frequency components at approximately 150 kHz). The fracture mainly controlled by the shale matrix tearing is flexible in profile because it is greatly affected by the competition of microcracks and local natural defects in the process of initiation and propagation. The fracture controlled by the opening of the bedding layer is a straight line with the rough surface and the fracture controlled by the shearing on the bedding layer is a straight line with the smooth surface. Finally, the fracture predominantly controlled by friction on the microcrack surface is generally arched. This work is helpful in providing considerations for depicting the probable fracture planar profile and explaining the microdamage mechanism, allowing for the enhancement of human control when constructing complex underground fracture networks in shale reservoirs.

We investigate the effects of spin squeezing interaction, external magnetic field and temperature on dense coding capacity properties in two kinds of two-qubit spin squeezing model: one-axis twisting model (OATM) and two-axis countertwisting model (TACM). To the OATM, it is found that the value of dense coding capacity χ is larger than 1 in the region of larger values of Ω(external magnetic filed) and μ(squeezing interaction) parameters space, while in the region of lower values of Ω and μ parameters space, χ is always less than 1 and not valid for dense coding. With increasing temperature T the dense coding capacity is decayed, and one can carry out the valid dense coding in the lower T region through tuning Ω. To the TACM, it is found that the value of χ is promoted with increasing the squeezing parameter γ. Through increasing γ, χ finally reached to one stable value, which is always larger than 1 whatever value of Ω is. The valid dense coding capacity χ can be enhanced through tuning the parameter Ω or γ, but it is decreased with increasing T. Our results show that with proper enhancing the parameter Ω or γ it is easy to carry out the valid dense coding (χ > 1) and the optimal dense coding (χ = 2) when the system in TACM.

A NiO flake and reduced graphene oxide sheet (NiO/RGO) composite was synthesized via an in situ ultrasonic agitation method after heat calcination in a nitrogen atmosphere. The NiO/RGO composite displayed a high reversible capacity of 825 mA h/g after 50 cycles at 100 mA/g, which was higher than the pure NiO flakes (197 mA h/g). The RGO sheets (115 mA h/g) used in lithium-ion batteries as anode materials. The NiO/RGO electrode showed excellent rate capacities that were higher than the pure NiO flakes and the RGO sheets electrodes within the same experimental conditions. These improvements could be attributed to the RGO sheets improved the electrical conductivity of NiO flakes and buffered the volume expansion of the NiO/RGO composite electrode during lithium cycling.

In this paper, a type of macroporous carbon (MPC) material was produced using water-soluble sodium carbonate (Na2CO3) as the template and glucose as the carbon precursor. After annealing in an argon atmosphere (Ar) at 700 °C, the samples exhibited specific surface areas up to 600 m2 g−1 with different proportions of sodium carbonate and glucose. When the samples were employed as anode materials in lithium-ion batteries, the electrodes delivered a stable reversible capacity at 200 mA g−1 and favourable cycling stability at 500 mA g−1. Moreover, all MPC samples exhibited excellent rate performances at 5000 mA g−1.

Conflict-resolution methods have been applied to water resources management to balance conflicting interests of stakeholders. Due to the climate change impacts on hydrologic processes, the strategy selections of conflict-resolution methods can be influenced, resulting in different selection rules for historical and future periods. This study aims to quantify the impacts of climate change on the strategy-selection rules of the conflict-resolution methods for better long-term strategic decision-making. The methodology of this study consists of climatic, hydrological, environmental and multi-objective optimization models, two fuzzy social choice methods (FSCMs) and four game-theoretical bargaining methods (GTBMs). The hydro-environmental conflict-resolution management in the Yangtze River of China is selected as the case study. The results show that the strategy selection of GTBMs is more stable and results in a better balance between hydropower and environmental objectives, compared to that of FSCMs. Moreover, considering climate change, under the appropriate environmental flow pattern, the stabilities of the strategy selections of FSCMs and GTBMs are slightly influenced, and the average satisfied degrees of both objectives obtained by FSCMs and GTBMs in the future period (2021-2080) are lower than those in the base period (1950-2012). The findings from this study provide guidance for hydro-environmental conflict-resolution management from a sustainable development perspective.

Image inpainting algorithms based on separated priority are easily misled by image texture information, have poor accuracy in searching for matching patches with high priority and often result in inconsistent texture propagation and edge structure. Additionally, it is difficult to obtain the best-matching patch within a fixed range based on only color information. By considering the attention point of human vision and the statistical information of an image, an image inpainting algorithm based on saliency mapping and gray entropy is proposed. A saliency map is added to the priority stage, which ensures that the parts with strong structural information and visual importance are completed preferentially. The best-matching patch is determined by comprehensively considering the color information and saliency features. The search range of the matching patch is adaptively controlled based on gray entropy. Experiments concerning scratch damage, text removal and large area object removal are compared. The results of the proposed method have better visual effects and are superior in regard to the consistency of the edge structure and texture. The efficiency is similar to methods with a fixed local search range. The objective evaluation results also validate the performance of the proposed method.

In 2008, Blockchain was introduced to the world as the underlying technology of the Bitcoin system. After more than a decade of development, various Blockchain systems have been proposed by both academia and industry. This paper focuses on the consensus algorithm, which is one of the core technologies of Blockchain. In this paper, we propose a unified consensus algorithm process model that is suitable for Blockchains based on both the chain and directed acyclic graph (DAG) structure. Subsequently, we analyze various mainstream Blockchain consensus algorithms and classify them according to their design in different phases of the process model. Additionally, we present an evaluation framework of Blockchain consensus algorithms and then discuss the security design principles that enable resistance from different attacks. Finally, we provide some suggestions for selecting consensus algorithms in different Blockchain application scenarios.

Photoionization (PI) cross sections of the ground state 3s23p 2P°1/2 and metastable state 3s23p 2P°3/2 of Al-like Sc are investigated using the Dirac R-matrix method. The current energy levels and radiative transition rates are consistent with experimental results and previous theory. Our calculated ionization energies of the ground and metastable states are in accordance with the experimental values. The PI cross sections show good agreement between length and velocity forms. Partial-wave contributions to the total PI of ground and metastable states are discussed. Moreover, the PI cross sections are dominated by a large number of resonances from the Rydberg series of autoionizing states. In addition to providing data for the Opacity Project TOPbase, the present work promotes plasma simulation and diagnosis.

In recent years, the increasing demand for flexible and wearable devices requires the synthesis of novel stretchable and piezoresistive materials. Piezoresistive polymer composites are popular due to their excellent piezoresistivity and high stretchability, which can readily be attached to clothes or human body. In this study, a stretchable and sensitive strain sensor based on multi-wall carbon nanotube (MWCNT)/polydimethylsiloxane (PDMS) composite with an excellent overall performance was fabricated in a facile and effective way. The composite with 7% MWCNTs is ideal for strain sensor compared to those with 5% and 9% MWCNTs. Not only can the gauge factor reach 5–9 under 10–40% strain, but also the curve of relative change in resistance versus strain is almost linear. The strain sensor can respond immediately with low hysteresis. The strain sensor also exhibits great stability under 1000 cycles of stretching/releasing, demonstrating the desirable long-term endurance to mechanical stimuli as well. The strain sensor was then implemented to monitor human motions (finger and wrist bending), precisely sensing the motion deformation and states. In conclusion, the reported sensor based on MWCNT/PDMS composite possesses numerous favorable characteristics including high sensitivity, good stretchability, ease of fabrication, and promising practical application in the field of biomedical system and wearable electronic devices.

The elastic polymer composite embedded with carbon nanotubes (CNTs) is an ideal candidate for stretchable and flexible sensor fabrication due to the perfect combination between the excellent properties of CNTs and the high stretchability of the elastomer. A cube model of nanotube/polymer composite is constructed to comprehensively and theoretically analyze its electrical behavior, which is dominantly governed by the CNT network. The aspect ratio and alignment of CNTs significantly influence both the percolation threshold range and the electrical conductivity; however, the electrical conductivity of CNTs has little impact on the percolation threshold. The piezoresistivity of the composite is not only governed by the property of CNTs but also by the mechanical property of the polymer matrix, including the Poisson’s ratio and alignment of CNTs. The specific reasons why the composite resistance rises when it is stretched are investigated. Finally, one optimizing suggestion is given for making the CNTs/polymer composite with high sensitivity.

Fusiform shape MnO/C composite was fabricated for the first time by heat calcining of MnCO3/C precursor, which was produced via a two-step hydrothermal method using glycine, KMnO4 and glucose as reagents. When the composite applied in LIBs as anode materials, the electrodes deliver a reversible capacity as high as 691 mA h g−1 after 120 cycles at a current density of 100 mA g−1 and can retain a stable capacity of 187 mA h g−1 at 1000 mA g−1. Compared with pure MnO particles sample, the enhanced electrochemical performances of MnO/C electrodes were attributed to the carbon layers can effectively improve the transfer rate of electrons and buffer the volume expansion of MnO particles during the charge/discharge process.

Ternary organic solar cells (OSCs) hold great promise in enabling the roll-to-roll printing of environmentally friendly, mechanically flexible, and cost-effective photovoltaic devices. Nevertheless, many ternary OSCs display the best power conversion efficiency (PCE) with a thin active layer at the thickness of about 100 nm, which can be hardly translated in to the roll-to-roll processing with high reproducibility. In this paper, the ternary OSCs with a high PCE and a thick active layer were reported, which was obtained by incorporating a dye small molecule named as 2’-(5,5’-(9,9-dioctyl-9H-fluorene-2,7-diyl)bis(thiophene-5,2-diyl))bis(methanylylidene))-bis(3-ethyl-2-thioxothizolidin-4-one) (FTR)) into a PTB7-Th:PC71BM binary system. Specifically, the addition of FTR into the PTB7-Th:PC71BM binary system was found to improve the hole mobility of the active layer, which resulted in faster charge transport, more efficient charge separation, and higher PCEs even in the presence of a thick active layer. The single-junction PTB7-Th:FTR:PC71BM ternary OSCs with the active layer thickness of 160 nm presented an outstanding PCE of 9.4%, which was much higher than that 7.5% of the PTB7-Th:PC71BM binary OSCs with the active layer thickness of 160 nm. Notably, the PTB7-Th:FTR:PC71BM ternary OSCs devices exhibited excellent thickness insensitivity. In other words, the PTB7-Th:FTR:PC71BM ternary OSCs device with a thick active layer (200 nm) could still demonstrate a high PCE of over 8.2%, which was well compatible to the requirement for future roll-to-roll printing.