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Elastic pressure sensors play a crucial role in the digital economy, such as in health care systems and human–machine interfacing. However, the low sensitivity of these sensors restricts their further development and wider application prospects. This issue can be resolved by introducing microstructures in flexible pressure-sensitive materials as a common method to improve their sensitivity. However, complex processes limit such strategies. Herein, a cost-effective and simple process was developed for manufacturing surface microstructures of flexible pressure-sensitive films. The strategy involved the combination of MXene–single-walled carbon nanotubes (SWCNT) with mass-produced Polydimethylsiloxane (PDMS) microspheres to form advanced microstructures. Next, the conductive silica gel films with pitted microstructures were obtained through a 3D-printed mold as flexible electrodes, and assembled into flexible resistive pressure sensors. The sensor exhibited a sensitivity reaching 2.6 kPa−1 with a short response time of 56 ms and a detection limit of 5.1 Pa. The sensor also displayed good cyclic stability and time stability, offering promising features for human health monitoring applications. [ABSTRACT FROM AUTHOR]

Electronic skin (e-skin) has the potential to detect large-scale strain, which is typically achieved by integrating multiple strain sensors into an array. However, the latency and limited resolution of sensing have hindered its large-scale sensing applications. Here, we have developed a high-resolution detection sensing system capable of detecting static and dynamic strain with a simple fabrication process by combining capacitive and mechanoluminescent (ML) sensor units. An elastic polydimethylsiloxane (PDMS) composite film doped with ZnS:Cu and BaTiO3(BT) particles are fabricated as the functional film of the capacitive sensor. In contrast, the transparent electrode was fabricated on the surface of the as-prepared film. By incorporating BT nanoparticles into the elastic substrate, the ML intensity of the ZnS:Cu was improved up to 2.89 times that without BT addition, and the sensitivity of the capacitive sensor was increased as well. The capacitive part of the sensor presented a GF of 0.9 and good stability, while the ML part exhibited excellent performance, making it suitable for both static and dynamic sensing. Furthermore, the strain sensor integrated by 10 × 10 sensing units is demonstrated to detect large-scale strain with high resolution. Moreover, finger joint strain distribution tracking is achieved by attaching the strain sensor unit to the finger joint. With these characteristics, the e-skin may have great potential for bio-motion monitoring and human-computer interaction applications. [ABSTRACT FROM AUTHOR]

As an indispensable part of wearable devices and mechanical arms, stretchable conductors have received extensive attention in recent years. The design of a high-dynamic-stability, stretchable conductor is the key technology to ensure the normal transmission of electrical signals and electrical energy of wearable devices under large mechanical deformation, which has always been an important research topic domestically and abroad. In this paper, a stretchable conductor with a linear bunch structure is designed and prepared by combining numerical modeling and simulation with 3D printing technology. The stretchable conductor consists of a 3D-printed bunch-structured equiwall elastic insulating resin tube and internally filled free-deformable liquid metal. This conductor has a very high conductivity exceeding 104 S cm−1, good stretchability with an elongation at break exceeding 50%, and great tensile stability, with a relative change in resistance of only about 1% at 50% tensile strain. Finally, this paper demonstrates it as a headphone cable (transmitting electrical signals) and a mobile phone charging wire (transmitting electrical energy), which proves its good mechanical and electrical properties and shows good application potential. [ABSTRACT FROM AUTHOR]

A retrospective study was conducted on 51 patients undergoing hip fracture surgery to investigate the factors associated with the formation of deep venous thrombosis (DVT). The independent sample t-test and correlation analysis were used to sort out and analyze the data. The findings are as follows. (1) Different gender samples showed significant differences in the Caprini score and thrombus location. Most DVTs in females are located in the posterior tibial vein and intermuscular veins. The Caprini score of females was significantly higher than that of males. (2) Age displays a positive correlation with DVT, coronary heart disease, hypertension, and different surgical types, respectively. (3) There is a correlation between age and operation duration. (4) Hyperlipidemia and cerebrovascular disease show a positive correlation with DVT. (5) There was a significant negative correlation between the Caprini score and the quantification of D-dimer. This indicates that in this sample, the higher the patients' Caprini score is, the lower the quantitation of D-dimer will be. (6) Hyperlipidemia and cardiac insufficiency show a positive correlation with cerebrovascular disease. Patients with hyperlipidemia and cardiac insufficiency may also suffer from cerebrovascular diseases. [ABSTRACT FROM AUTHOR]

In this study, the matched case-control study was used. Nineteen cases of severe pain in the early postoperative period among 55 patients were set as the observation group, and 57 cases of simultaneous rotator cuff repair without severe pain were matched in a 1 : 3 ratio as the control group. Patients' general information, disease characteristics, anesthesia and analgesia scheme, and operation information were collected. Frequency statistics, Wilcoxon signed rank sum test, regulatory effect analysis, and Poisson regression analysis were performed on these data. Some findings are included in the analysis. (1) There was a markable difference of 0.01 between the preoperative 48 h maximum pain value and the postoperative 48 h maximum pain value in the observation group. (2) There was a markable difference of 0.01 between the size and shape of the wound tear and the maximum pain value at 48 h after operation in the observation group. (3) When the number of opioid use affected the maximum pain value at 48 h after operation, the regulatory variables (type, quantity, and number of days of postoperative analgesics) were at different levels, and the impact amplitude had markable differences. (4) Age has a markable negative impact on the postoperative hospital stay. (5) The operation duration has a markable positive relationship with the postoperative hospital stay. (6) The analgesic pump had a markable positive impact on the postoperative hospital stay. (7) The location of injury did not affect the postoperative hospital stay. [ABSTRACT FROM AUTHOR]

Suppressing non‐radiative recombination via passivating surface defects of perovskite films has demonstrated an excellent strategy for high‐performance perovskite solar cells (PSCs). However, it is still hard to realize both high open‐circuit voltage (Voc) of >1.2 V and high power conversion efficiency (PCE) of >22%, because the optimized bandgap of perovskite films is less than 1.60 eV for efficient light harvesting and Voc deficit is generally unavoidable due to carriers recombination. Here, the surface of the perovskite film is treated with a series of phenylhydroxylammonium halide salts and it is found that all of them can remarkably prolong the carrier lifetime owing to their excellent capability of surface defects passivation. The best PSC with phenylbutylammonium bromide treatment realizes a PCE of 22.67% with a Voc of 1.216 V, corresponding to a small Voc deficit of ≈344 mV. [ABSTRACT FROM AUTHOR]

The anaerobic treatment process is a complicated multivariable system that is nonlinear and time varying. Moreover, biogas production rates are an important indicator for reflecting operational performance of the anaerobic treatment system. In this work, a novel model fuzzy wavelet neural network based on the genetic algorithm (GA-FWNN) that combines the advantages of the genetic algorithm, fuzzy logic, neural network, and wavelet transform was established for prediction of effluent quality and biogas production rates in a full-scale anaerobic wastewater treatment process. Moreover, the dataset was preprocessed via a self-adapted fuzzy c-means clustering before training the network and a hybrid algorithm for acquiring the optimal parameters of the multiscale GA-FWNN for improving the network precision. The analysis results indicate that the FWNN with the optimal algorithm had a high speed of convergence and good quality of prediction, and the FWNN model was more advantageous than the traditional intelligent coupling models (NN, WNN, and FNN) in prediction accuracy and robustness. The determination coefficients R2 of the FWNN models for predicting both the effluent quality and biogas production rates were over 0.95. The proposed model can be used for analyzing both biogas (methane) production rates and effluent quality over the operational time period, which plays an important role in saving energy and eliminating pollutant discharge in the wastewater treatment system. [ABSTRACT FROM AUTHOR]

We report the synthesis, ab initio calculations, magnetic and optical characterization of a DyIII-based dimeric compound named DyAZO. The dimers self-organize into a supramolecular chain decorated with photo-isomerizable azobenzene ligands. DyAZO displays single-molecule magnet (SMM) behavior. However, ab initio calculations highlight a quite strong admixture of MJ states of the 6H15/2 level of DyIII ions, the presence of low-lying excited MJ states and antiferromagnetic Dy–Dy dipolar coupling. This favors zero-field fast tunneling. Accordingly the Dy-doped analogue YDyAZO (5.5% Dy doping) displays enhanced magnetic relaxation with a hysteresis that is observed at 0.5 K. The influence of the cis- to trans-isomerization of the decorating azobenzene ligand on magnetic properties has been tested for both solid samples and solutions of DyAZO and YDyAZO. This provides hints for the synthesis of future Dy-based photo-isomerizable molecules. [ABSTRACT FROM AUTHOR]

Little information is available about the occurrence of neonicotinoid insecticides in surface water and sediment of the metropolitan regions around the rivers in China. Here we investigate the residual level of neonicotinoids in the Guangzhou section of the Pearl River. At least one or two neonicotinoids was detected in each surface water and sediment, and the total amount of neonicotinoids (∑ 5 neonics) in surface water ranged from 92.6 to 321 ng/L with a geometric mean (GM) of 174 ng/L. Imidacloprid, thiamethoxam and acetamiprid were three frequently detected neonicotinoids (100%) from surface water. As for the sediment, total concentration was varied between 0.40 and 2.59 ng/g dw with a GM of 1.12 ng/g dw, and acetamiprid and thiacloprid were the common sediment neonicotinoids. Western and Front river-route of the Guangzhou section of the Pearl River suffered a higher neonicotinoids contamination than the Rear river-route, resulting from more effluents of WWTPs receiving, and intensive commercial and human activities. Level of residual neonicotinoids in surface water was significantly correlated with the water quality (p < 0.01), especially items of pH, DO and ORP, and nitrogen and phosphorus contaminants. Compared with reports about residual neonicotinoids in water and sediment previously, the metropolitan regions of the Guangzhou could be confronted with a moderate contamination and showed serious ecological threats (even heavier than the Pearl Rivers). Our results will provide valuable data for understanding of neonicotinoids contamination in the Pearl River Delta and be helpful for further assessing environmental risk of neonicotinoids. Image 1 • Occurrence of neonicotinoids in the Guangzhou section of the Pearl River is examined. • At least one or two neonicotinoids was detected in each water and sediment sample. • IMI, THM and ACE were frequently detected (100%) neonicotinoids from surface water. • Western- and Front-suffered a higher neonicotinoids contamination than Rear river-route. • The Guangzhou section of the Pearl River could be confronted with a moderate neonicotinoid contamination. This article evaluates the residual level and distribution of neonicotinoids in the Guangzhou section of the Pearl River, South China. It is of great significance to fully understand the migration, transformation, contamination situation and ecological risk of neonicotinoid insecticides. [ABSTRACT FROM AUTHOR]

The explosive increase in digital communications in the Big Data and internet of Things era spurs the development of universal memory that can run at high speed with high-density and nonvolatile storage capabilities, as well as demonstrating superior mechanical flexibility for wearable applications. Among various candidates for the next-generation information storage technology, resistive switching memories distinguish themselves with low power consumption, excellent downscaling potential, easy 3D stacking, and high CMOS compatibility, fulfilling key requirements for high-performance data storage. Employing organic and hybrid switching media in addition allows light weight and flexible integration of molecules with tunable device performance via molecular design-cum-synthesis strategy. In this review, we present a timely and comprehensive review of the recent advances in organic and hybrid resistive switching materials and devices, with particular attention on their design principles for electronic property tuning and flexible device performance. The current challenges posed with development of organic and hybrid resistive switching materials and flexible memory devices, together with their future perspectives, are also discussed. [ABSTRACT FROM AUTHOR]

The residue levels and composition profiles of phthalate acid esters (PAEs) in water and sediment samples were investigated in eight urban lakes of Guangzhou, China. A total of 23 water and 16 sediment samples were collected. Results showed that all target PAEs were detected with dimethyl phthalate and di(2-ethylhexyl) phthalate as the most abundant compounds. The total concentrations of PAEs from different urban lakes were in the range of 273–1173 ng/L for water and 16.5–242 ng/g for sediments, with the geometric mean of 515 ng/L and 75.0 ng/g, respectively. Zhongshan Park Lake and Liwan Lake were the most highly contaminated with PAEs in water and in sediment, respectively. The spatial distribution of PAEs exhibited that distribution coefficients of PAEs between sediment and water are consistent with hydrophilicity of PAEs, and pollution levels and characteristics of PAEs in different lakes had a close relationship with the geographical location of the lake, industrial and commercial types, population density, and the association between the lake and the Pearl River. According to Pearson correlation analysis, PAEs would be derived from similar or identical sources. Risk assessment suggested that the exposure of PAEs in Guangzhou has a moderate toxicity at the current level. [ABSTRACT FROM AUTHOR]

Water quality prediction is the basis of water environmental planning, evaluation, and management. In this work, a novel intelligent prediction model based on the fuzzy wavelet neural network (FWNN) including the neural network (NN), the fuzzy logic (FL), the wavelet transform (WT), and the genetic algorithm (GA) was proposed to simulate the nonlinearity of water quality parameters and water quality predictions. A self-adapted fuzzy c-means clustering was used to determine the number of fuzzy rules. A hybrid learning algorithm based on a genetic algorithm and gradient descent algorithm was employed to optimize the network parameters. Comparisons were made between the proposed FWNN model and the fuzzy neural network (FNN), the wavelet neural network (WNN), and the neural network (ANN). The results indicate that the FWNN made effective use of the self-adaptability of NN, the uncertainty capacity of FL, and the partial analysis ability of WT, so it could handle the fluctuation and the nonseasonal time series data of water quality, while exhibiting higher estimation accuracy and better robustness and achieving better performances for predicting water quality with high determination coefficients R2 over 0.90. The FWNN is feasible and reliable for simulating and predicting water quality in river. [ABSTRACT FROM AUTHOR]

Single‐molecule magnet (SMM) behavior of dysprosium‐based dimers was optimized by substitution of a DyIII ancillary ligand (hfac– in the previously reported DyPyNO and tta– in Dy). A clear hysteresis opening is visible at 0.5 K for Dy that allows for the determination of an antiferromagnetic (AF) coupling of –2.92 cm–1 (S = 1/2, gz = 19.58) which was confirmed by ab initio calculations. Comparison with the results of DyPyNO shows that stronger AF coupling correlates with better SMM behavior. This is further demonstrated by diamagnetic substitution, and a Y–Dy species (YDy) highlights that the strong AF magnetic interaction in Dy significantly enhances magnetic relaxation at low temperature. This coupling is also expected to be at the origin of the unexpectedly weak isotopic effect observed for the isotopically pure parents of Dy, namely 161Dy and 164Dy. [ABSTRACT FROM AUTHOR]

Structural regular polyaniline was synthesized via a modified-chemical oxidative polymerization reaction. Highly hydrophilic polyaniline (PANi) and polyaniline-poly(vinylidene fluoride) blend (PANi-PVDF) membranes were prepared by solution casting and phase inversion techniques. Both of the mechanical and filtration properties of the membranes depend on the polymer composition and doping level of the blends. The elasticity of the membrane is greatly improved upon introducing poly(vinylidene fluoride) into the blend. The water permeability of the blend membranes is further enhanced when the membranes are doped with hydrochloric acid. The PANi-PVDF blend membranes are capable of recovering metallic gold from the acid/halide leaching streams spontaneous and sustainably, and are promising candidates for wastewater treatments in electronic industries. [ABSTRACT FROM AUTHOR]

Owing to their attractive performance in photovoltaic devices, organolead halide perovskite materials have attracted enormous interest for photodetector applications. However, current perovskite-based photodetectors mainly rely on high-conductive 2D materials such as graphene or transition metal sulfides to transport photocarriers, which indeed significantly improve the photoresponsivity but seriously weaken other parameters such as on/off ratio or response speed. Achieving a high overall performance remains a challenge. Here, a solution-processed TiO2 nanocrystal (NC) film is employed to transport photocarriers. The designed TiO2 NC/perovskite (CH3NH3PbI3) bilayer device exhibits satisfactory overall performance with on/off ratio of 4000, photodetectivity of 1.85 × 1012 Jones, and rise/decay time of 0.49/0.56 s. The device can also be integrated on flexible polyimide substrate. This work provides a strategy to realize high-performance perovskite-based photodetectors and clearly demonstrates their potential applications in future flexible optoelectronics. [ABSTRACT FROM AUTHOR]

The social and ecological influence of Neonicotinoids (NEOs) usage in agriculture sector is progressively higher. There are seven NEOs insecticides widely used for the insects control. Among the NEOs, thiacloprid (THD) was extensively used for insect control during crop cultivation. This study targets to analyse the contamination levels of NEOs in agricultural soil and identify photo-biodegradation of THD degradation using pure isolates and mixed consortium. The photo degradation (PD), biodegradation (BD) and photo-biodegradation (PBD) of THD were compared. The corn field agricultural soils were polluted by four NEOs, among them THD had greater contamination level (surface soil: 3901.2 ± 0.04 μg/g) and (sub-surface soil: 3988.6 ± 0.05 μg/g). Three soil free enriched bacterial strains following Bacillus atrophaeus (PB-2), Priestia megaterium (PB-3) (formerly known as Bacillus megaterium), and Peribacillus simplex (PB-4) (formerly known as Bacillus simplex) were identified by microbiological and molecular 16s rRNA gene sequencing. The PD, BD and PBD of THD were conducted and degradation rate was detected by instrument UPLC-MS-MS. The PBD process with blue-LEDs showed better THD degradation efficiency than PD and BD, where the specific THD degradation rate was 85 ± 0.2%, 87 ± 0.5%, and 89 ± 0.3%, respectively for PB-2, PB-3 and PB-4. Then, the photo-biodegradation performance is greater at 150, 175, 200 rpm, pH 7.0–9.0, and temperature 30–35 °C. After the PBD system deliver four intermediate metabolites, the THD degradation process maybe through nitro reduction, hydroxylation and oxidative cleavage pathway. [Display omitted] • This study to assess soil contamination and neonicotinoids degradation investigated by different method. • The neonicotinoids pollution was detected on surface and sub-surface agriculture soil. • Imidacloprid and thiacloprid were abundant in soils, clothianidin and thiamethoxam were lesser. • Degradation of thiacloprid by blue-LEDs with bacteria had greater performance. • Four biotransformation metabolites was identified from thiacloprid photo-biodegradation. [ABSTRACT FROM AUTHOR]

In this study, an artificial synapse with a sandwich structure of Ta/ethyl viologen diperchlorate [EV(ClO4)2]/triphenylamine-based polyimide (TPA-PI)/Pt is fabricated directly on a flexible PET substrate and exhibits distinctive history-dependent memristive behaviour, which meets the basic requirements for synapse emulation. Essential synaptic plasticity (including long-term plasticity and short-term plasticity) and some memory and learning behaviours of human beings (including the conversion from short-term memory to long-term memory and the “learning–forgetting–relearning”) have been demonstrated in our device. More importantly, the device still exhibits the synaptic performance when the surface strain of the device reaches 0.64% (or, the bending radius reaches 10 mm). Moreover, the device was able to endure 100 bending cycles. Our findings strongly demonstrate that the organic artificial synapse is not only promising for constructing a neuromorphic information storage and processing system, but is also interesting for the realization of wearable neuromorphic computing systems. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs), which are formed by association of metal cations or clusters of cations ('nodes') with soft organic bridging ligands ('linkers'), are a fascinating class of flexible crystalline hybrid materials offering potential strategy for the construction of flexible electronics. In this study, a high-quality MOF nanofilm, HKUST-1, on flexible gold-coated polyethylene terephthalate substrates is fabricated using liquid phase epitaxy approach. Uniform and reproducible resistive switching effect, which can be sustained under the strain of as high as 2.8%, and over the wide temperature range of -70 to +70 °C, is observed for the first time in the all solid-state Au/HKUST-1/Au/thin film structures. Through conductive atomic force microscopic and depth-profiling X-ray photoelectron spectroscopicanalysis, it is proposed that the electric field-induced migration of the Cu­2+ ions, which may lead to subsequent pyrolysis of the trimesic acid linkers and thus the formation of highly conducting filaments, could be the possible origin for the observed uniform resistance switching in HKUST-1 nanofilms. [ABSTRACT FROM AUTHOR]

Herein, we provide some structural evidence of the complexation color-change of murexide solutions in presence of lanthanide, which has been used for decades in complexometric studies. For Ln=Sm to Lu and Y, the compounds crystallize as monomeric [Ln(Murex)3] ⋅11 H2O with an N3O6 tricapped square-antiprism environment, which are stable up to 250 °C. Single-ion magnet (SIM) behavior is then observed on the YbIII derivative in an original nine-coordinated environment. In-field slow relaxation (Δ=(15.6±1) K; τ0=2.73×10−6 s) is observed with a very narrow distribution of the relaxation time ( αmax=0.09). Magnetic and photophysical properties can be correlated. On one hand the analysis of NIR emission spectrum permits to have access to crystal field parameters and to compare them with those extracted from dc measurements. On the other hand, magnetic measurements permit to identify the nature of the MJ states involved in the 2F5/2→2F7/2 luminescence spectrum. The gap between the low-lying states is in agreement with the energy barrier obtained from magnetic slow-relaxation measurement. [ABSTRACT FROM AUTHOR]

The reaction of isonicotinic acid N-oxide and Dy(NO)3 ·6H2O under aerobic conditions leads to the formation of a porous lanthanide, a cubane-based 3D edifice of the formula [Dy4(μ3-OH)3(μ3-O)(NOPyCOO)6(OH)(H2O)3 ·(DMF)3(H2O)12]∞ (NOPyCOO = pyridine-4-carboxylate N-oxide). Crystal structure investigations show that the [Dy4(μ3-OH)3(μ3-O)] cubane cores are interconnected by organic ligands to form an extended porous structure. Thermogravimetric analyses and temperature-dependent X-ray diffraction analyses evidence that the compound is stable upon dehydration/desolvatation up to 200 °C. Calculations for the N2 kinetic radius afford a void volume of 3603 Å3 per unit cell (33.8 %) and a potential porosity of 1400 m2 g-1. The large pores can potentially host molecules with a projected surface area as large as 20 Å2 into a large pore volume (600 Å3). Moreover, the onset of a slow magnetic relaxation has been observed and rationalized by a comparison with closely related 0D and 2D compounds. [ABSTRACT FROM AUTHOR]