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In the field of computer vision, without sufficient labeled images, it is challenging to train an accurate model. However, through visual adaptation from source to target domains, a relevant labeled dataset can help solve such problem. Many methods apply adversarial learning to diminish cross-domain distribution difference. They are able to greatly enhance the performance on target classification tasks. Generative adversarial network (GAN) loss is widely used in adversarial adaptation learning methods to reduce an across-domain distribution difference. However, it becomes difficult to decline such distribution difference if generator or discriminator in GAN fails to work as expected and degrades its performance. To solve such cross-domain classification problems, we put forward a novel adaptation framework called generative adversarial distribution matching (GADM). In GADM, we improve the objective function by taking cross-domain discrepancy distance into consideration and further minimize the difference through the competition between a generator and discriminator, thereby greatly decreasing cross-domain distribution difference. Experimental results and comparison with several state-of-the-art methods verify GADM's superiority in image classification across domains.

High energy density and enhanced rate capability are highly sought-after for supercapacitors in today’s mobile world. In this work, polyaniline/titanium carbide (MXene) (PANI/Ti3C2Tx) nanohybrid is synthesized through a facile and cost-effective self-assembly of one-dimensional (1D) PANI nanofibers and two-dimensional (2D) Ti3C2Tx nanosheets. PANI/Ti3C2Tx delivers greatly improved specific capacitance, ultrahigh rate capability (67% capacitance retention from 1 to 100 A·g−1) as well as good cycle stability. Electrochemical kinetic analysis reveals that PANI/Ti3C2Tx is featured with surface capacitance-dominated process and has a quasi-reversible kinetics at high scan rates, giving rise to an ultrahigh rate capability. By using PANI/Ti3C2Tx as positive electrode, an 1.8 V aqueous asymmetric supercapacitor (ASC) is successfully assembled, showing a maximum energy density of 50.8 Wh·kg−1 (at 0.9 kW·kg−1) and a power density of 18 kW·kg−1 (at 26 Wh·kg−1). Moreover, an 3.0 V organic ASC is also elaborately fabricated by using PANI/Ti3C2Tx, achieving an ultrahigh energy density of 67.2 Wh·kg−1 (at 1.5 kW·kg−1) and a power density of 30 kW·kg−1 (at 26.8 Wh·kg−1). The present work not only improves fundamental understanding of the structure-property relationship towards ultrahigh rate capability electrode materials, but also provides valuable guideline for the rational design of high-performance energy storage devices with both high energy and power densities.

Potassium-ion batteries (PIBs) are appealing alternatives to conventional lithium-ion batteries (LIBs) because of their wide potential window, fast ionic conductivity in the electrolyte, and reduced cost. However, PIBs suffer from sluggish K+ reaction kinetics in electrode materials, large volume expansion of electroactive materials, and the unstable solid electrolyte interphase. Various strategies, especially in terms of electrode design, have been proposed to address these issues. In this review, the recent progress on advanced anode materials of PIBs is systematically discussed, ranging from the design principles, and nanoscale fabrication and engineering to the structure-performance relationship. Finally, the remaining limitations, potential solutions, and possible research directions for the development of PIBs towards practical applications are presented. This review will provide new insights into the lab development and real-world applications of PIBs.

A simple, convenient and label-free approach was developed for detection of acetylcholine (ACh) based on competitive enzymatic hydrolysis by use of liquid crystals (LCs) as a sensing medium. Self-assembled monolayers of myristoylcholine (Myr) were obtained at the aqueous/LC interface when the surfactants were in contact with LCs, resulting in a perpendicular orientation of LCs at the interface. Thus, LCs displayed a dark optical image. However, enzymatic hydrolysis of Myr by acetylcholinesterase (AChE) disturbed the Myr monolayers, which led to a horizontal orientation of LCs at the interface, thereby inducing a dark-to-bright shift of the LCs optical appearance. Interestingly, as ACh was also a substrate of AChE, the bright appearance of LCs was prevented when incubating the mixture of AChE and ACh with Myr decorated aqueous/LC interface due to the competitive enzymatic hydrolysis between Myr and ACh by AChE. By using this strategy, ACh could be detected selectively and sensitively, with a broad linear range from 0.01 μmol/L to 1 mmol/L and a low detection limit of 14.5 nmol/L. The results showed that the competitive enzymatic hydrolysis-assisted LC-based sensor had potential applications in ACh detection.

Hexavalent chromium is highly toxic and regarded as one of the main pollutants in the environment. Sophisticated laboratory instruments are commercially available for the in-field determination of chromium. It is highly desirable to develop affordable, portable, sensitive and reliable methods for on-site Cr(VI) detection. For field analysis, we designed a smartphone-based absorbance device with an ultralong absorption path to improve sensitivity. The intensity of the transmission light was detected by the illumination sensor in the smartphone. The absorption path was enlarged to a maximum of 83.5 cm by 41 reflection cycles. The intensity of the reflected light in an empty colorimetric cell can be serviced as the internal references to correct the possible baseline drift due to light source intensity decay. The absorbance measured by the proposed device obeys the Lambert–Beer law in the range of 0–1.1. This device was used to determine Cr(VI) in water samples on-site by using 1,5-diphenylcarbazide as a colorimetric reagent, with the linear range of 1–18 μg L−1 and limit of detection of 0.26 μg L−1. This simple absorbance device offers the advantages of cost-effectiveness, ease of implementation, portability, sensitivity and reliability for field analysis.

Benzo[a]pyrene (Bap) is one of the main organic pollutants in the atmospheric haze that is rich in fine water drops and particulate matters. The understanding of the Bap's form in water is of great importance to unveil its real biological effects toward the respiratory system. To date, various reports have documented its toxicological effects in the molecular form. Herein, we found that Bap existed as self-aggregated nanoclusters of tunable sizes rather than as dissolved molecules in water and different sized nanoclusters illustrated varied cytotoxicity. These findings indicated that the size, which has been ignored in previous studies, is also a dominant parameter similar to the molecular concentration for determining Bap's cytotoxicity. Polystyrene (PS) nanoparticles, as a model for nanoplastics, could adsorb Bap nanoclusters and serve as carriers that enter the cells. The combination effect interestingly altered the cytotoxicity distinction of Bap of different sizes. The intracellular fate of the nanoparticles and subcellular organelle damages were studied to unveil the mechanisms of cytotoxic distinction. Small Bap nanoclusters entered cells faster than their large counterparts. The Bap of the PS@Bap complex was stably adsorbed on PS at the early stages of endocytosis until it was detached during the lysosomal transport and maturation process. The dissociated Bap may bypass the lysosome pathway and be released into the cytosol with a nanocluster structure or relocate into the endoplasmic reticulum. On the other hand, the detached PS preferred to bind to the mitochondria or be excreted out of the cell via the lysosomal pathway. Moreover, the PS@Bap complex resulted in a significant loss of the mitochondrial membrane potential and induced apoptosis through the mitochondria-involved apoptosis pathway. This study provides a new perspective towards the toxicological mechanism of insoluble hydrophobic organic compounds and reveals the environmental significance of nanoplastics for regulating the biological effects of conventional pollutants.

Adenosine triphosphate (ATP), as a high-energy phosphate compound that stores and releases energy in living cells, has an irreplaceable role in many physiological processes and maintenance of biological functions, and can be used as an indicator of many diseases. In this work, a composite nanoprobe, silver nanocluster (AgNC) @ molybdenum disulfide (MoS2), was designed to achieve in situ fluorescence imaging and quantitative analysis of intracellular ATP in HeLa cells by fluorescence spectrometry and inductively coupled plasma mass spectrometry (ICP-MS). The probe was constructed based on the adsorption of DNA-AgNCs by MoS2 nanosheets, and the DNA-AgNCs were prepared with the ATP aptamer as a template, whose fluorescence was initially quenched by MoS2. When the probe was incubated into the cells, intracellular ATP recognized the aptamer sequence and caused the DNA-AgNCs to fall off the MoS2 nanosheets, resulting in fluorescence recovery. Here, AgNCs not only acted as a fluorescence label for imaging, but also as an element tag for quantitative analysis of intracellular ATP with the detection of 107Ag by ICP-MS. The ATP in HeLa cells detected by this method was 24.6 ± 1.7 nmol L−1, which was in good agreement with the test result of the ATP test kit (20.4 ± 0.8 nmol L−1). The proposed method has potential application in medical clinical diagnosis and evaluation of the body’s metabolic level via fluorescence imaging and ICP-MS detection of intracellular ATP.

The classification problems with imbalanced datasets widely exist in real word. An Extreme Learning Machine is found unsuitable for imbalanced classification problems. This work applies a Weighted Extreme Learning Machine (WELM) to handle them. Its two parameters are found to affect its performance greatly. The aim of this work is to apply various intelligent optimization methods to optimize a WELM and compare their performance in imbalanced classification. Experimental results show that WELM with a dandelion algorithm with probability-based mutation can perform better than WELM with improved particle swarm optimization, bat algorithm, genetic algorithm, dandelion algorithm and self-learning dandelion algorithm. In addition, the proposed algorithm is applied to credit card fraud detection. The results show that it can achieve high detection performance.

Molecularly imprinting polymers (MIPs), as artificial antibodies with high recognition selectivity to template molecules, are widely used in various biosensors. To improve further the selectivity of MIPs-based photoelectrochemical (PEC) biosensors, we report a differential strategy using non-imprinted polymers (NIPs) as the reference. In a proof-to-concept example for the determination of dopamine (DA), MIPs and NIPs membranes were fabricated by electrochemical polymerization of polypyrrole membranes on the surface of graphene quantum dots (GQDs)/TiO2 nanotubes (NTs). The photocurrent difference between the two PEC cells, MIPs@GQDs/TiO2 NTs−Pt and NIPs@GQDs/TiO2 NTs−Pt, was measured as the signal. As the non-specific adsorption of non-template molecules on the outside surface of MIPs and NIPs membranes is similar, the anti-interference ability for the determination of DA is much improved by using differential strategy. In the normal and differential PEC measurement models, 10.0 μM ascorbic acid is equivalent to 3.12 and 0.40 μM DA, respectively. Further, the smaller specific surface area in NIPs membrane was compensated by using a weight factor to correct the residual interference in a modified differential model. By using 10.0 μM ascorbic acid as the balance point, the presence of 10.0 μM H2O2, glutathione, uric acid or glucose is equivalent only to 0.090, 0.061,0.11 or 0.041 μM of DA, respectively, which are about 3–7% of their interference levels in the normal photocurrent model. The differential PEC method was applied in the determination of DA in serum samples in the linear range of 0.05–12.5 μM, with the detection limit of 0.018 μM.

In computer vision, when labeled images of the target domain are highly insufficient, it is challenging to build an accurate classifier. Domain adaptation stands for an effective solution to address it by utilizing available and related source domain which has sufficient labeled images, even when there is a substantial difference in properties and distributions of these two domains. Yet, most prior approaches merely reduce subspace conditional or marginal distribution differences between domains but entirely ignoring label dependence (LD) information of source data in subspace. This article proposes a novel approach of domain adaptation, called enhanced subspace distribution matching (ESDM), which makes good use of label information to enhance the distribution matching between the source and target domains in a shared subspace. It reduces both conditional and marginal distributions in a shared subspace during a procedure of kernel principal dimensionality reduction and also preserves source data LD information to the maximum extent, thereby significantly improving cross domain subspace distribution matching. We also provide a learning algorithm with highly affordable computation, which solves the ESDM optimization problem without using time-consuming iterations. Results confirm that it can well outperform several recent domain adaptation methods on image classification tasks in terms of classification accuracy and running time. The results can be used in social cognition, person reidentification, and human–machine interactions.

Lithium-ion capacitors (LICs) could combine the virtues of high power capability of conventional super-3capacitors and high energy density of lithium-ion batteries. However, the lack of high-performance electrode materials and the kinetic imbalance between the positive and negative electrodes are the major challenge. In this study, Fe3O4 nanoparticles encapsulated in nitrogen-rich carbon (Fe3O4@NC) were prepared through a self-assembly of the colloidal FeOOH with polyaniline (PANI) followed by pyrolysis. Due to the well-designed nanostructure, conductive nitrogen-rich carbon shells, abundant micropores and high specific surface area, Fe3O4@NC-700 delivers a high capacity, high rate capability and long cycling stability. Kinetic analyses of the redox reactions reveal the pseudocapacitive mechanism and the feasibility as negative material in LIC devices. A novel LIC was constructed with Fe3O4@NC-700 as the negative electrode and expanded graphene (EGN) as the positive electrode. The well-matched two electrodes effectively alleviate the kinetic imbalance between the positive and negative electrodes. As a result, Fe3O4@NC-700//EGN LIC exhibits a wide operating voltage window, and thus achieves an ultrahigh energy density of 137.5 W h kg−1. These results provide fundamental insights into the design of pseudocapacitive electrode and show future research directions towards the next generation energy storage devices.

With high energy density and low material cost, lithium-sulfur batteries (LSBs) emerge quite expeditiously as a fascinating energy storage system over the past decade. Broad applications of LSBs ranging from electric vehicles to stationary grid storage seem rather bright in recent literatures. However, there still exist many pressing challenges to be addressed because we do not yet fully understand and control the electrode-electrolyte interface chemistries during battery operation, such as polysulfide shuttling and poor utilization of active sulfur. Single-atom catalysts (SACs) pave new possibilities of tackling the tough issues due to their decent applicability in the atomic-level identification of structure-activity relationships and reaction mechanism, as well as their structural tunability with atomic precision. This review comprehensively summarizes the very recent advances in utilization of highly active SACs for LSBs by stating and discussing the related publications, which involves catalyst synthesis routes, battery performance, catalytic mechanisms, optimization strategies, and promises to achieve long-life, high-energy LSBs. We see that endeavors to employ SACs to modify sulfur cathode have allowed efficient polysulfide conversion and confinement, leading to the minimization of shuttle effect. Parallel efforts are being devoted to extending the scope of SACs to cell separator and lithium metal anode in order to unlock the full potential of LSBs. We also obtain mechanistic insights into battery chemistries and nature of SACs in their strong interactions with polysulfides through advanced in situ characterizations documented. Overall, acceleration in the development of LSBs by introducing SACs is noticeable, and this cutting edge needs more attentions to further promoting the design of better LSBs.

Computational simulation methods are used for characterizing the detailed attachment, diffusion and desorption of halogen vapor molecules in zeolitic imidazolate framework-8 (ZIF-8). The attachment energies of Cl2, Br2 and I2 are −55.2, −48.5 and −43.0 kJ mol−1, respectively. The framework of ZIF-8 is disrupted by Cl2, which bonds with Zn either on the surface or by freely diffusing into the cage. A framework deformation on the surface of ZIF-8 can be caused by the attachment of Br2, but only reorientation of the 2-methylimidazolate linkers (mIms) for I2. In diffusion, the halogen molecules have a tendency to vertically permeate the apertures of cages followed with swing effect implemented by the mIms. Larger rotation angles of mIms are caused by Br2 because of its stronger interaction with mIms than I2. A maximum of 7 Br2 or 5 I2 molecules can be accommodated in one cage. Br2 are clinging to the mIms and I2 are arranged as crystal layout in the cages, therefore in desorption processes molecules attached to the surface and free inside are desorbed while some remained. These results are beneficial for better understanding the adsorption and desorption processes of halogen vapors in the porous materials.

Classification technology plays an important role in machine learning. In the process of classification, the presence of noisy samples in datasets tends to reduce the performance of a classifier. This work proposes a clustering-based Noisy-sample-Removed Under-sampling Scheme (NUS) for imbalanced classification. First, the samples in the minority class are clustered. For each cluster, its center is taken as a spherical center, and the distance of the minority class samples farthest from the cluster center is taken as the radius to form a hypersphere. The Euclidean distance from the center of the cluster to every of the majority samples is calculated to decide if they are in the hypersphere. Then, we propose a NUS-based policy to decide if a majority sample in the hypersphere is a noisy sample. Similarly, the noises samples of the minority class are found. Second, We remove noisy-samples from the majority and minority classes and propose NUS. Finally, logistics regression, Decision Tree, and Random Forest are used in NUS as the base classifiers, respectively and compare with Random Under-Sampling (RUS), EasyEnsemble (EE), and Inverse Random Under-Sampling (IRUS) on 13 public datasets. Results show that our method can improve the classification performance in comparison with its state-of-the art peers.

In this work, we report a simple ratiometric electrochemiluminescence (ECL) method for ultra-sensitive immunoanalysis. A glassy carbon electrode (GCE) was modified by a mixture of porous g-C3N4 nanosheets and carbon nanotubes (CNTs). Secondary antibodies were labeled using CuS nanoparticles as the tags. After immune recognition, CuS nanoparticles in the immunocomplex were dissolved as Cu2+, which can quench the ECL of g-C3N4. The amount of Cu2+ was determined to quantify the concentration of the target antigen. To enhance the sensitivity, Cu2+ ions were firstly enriched and reduced to Cu on the surface of GCE/CNTs-g-C3N4, and the cathodic ECL of g-C3N4 was measured as the reference signal in the ratiometric ECL measurements. After applying a potential of 0.6 V (vs. Ag/AgCl) for 6 s, Cu was dissolved as Cu2+, which can quench the ECL of g-C3N4 with much higher efficiency because the freshly dissolved Cu2+ ions were distributed mainly within the Helmholtz layer of GCE/CNTs-g-C3N4. By using the ECL intensity ratio of GCE/CNTs-g-C3N4 (Cu2+) to GCE/CNTs-g-C3N4 (Cu) measured under the potentiostatic model as the signal indictor, the ratiometric ECL method was used to detect a biomarker of alpha fetoprotein with the limit of detection of 0.1 fg mL-1. It was shown that the influence of the difference in electrode modification and ECL measurement conditions on the determination of Cu2+ is suppressed greatly in the ratiometric ECL method. The combination of ratiometric ECL with electrochemical enrichment and biometallization is a useful strategy to enhance the sensitivity and reproducibility in immunoanalysis.

The continuous exploration of advanced electrode materials is of remarkable significance to revolutionize next-generation high-performance energy storage devices towards a green future. Benefiting from their electrochemically active sites and abundant redox centers, bimetallic selenides with desirable nanostructures recently have emerged as promising electrode alternatives for battery–supercapacitor hybrid (BSH) devices which demonstrate enormous potential in bridging the gap between electrochemical properties with high power densities (supercapacitors) and energy densities (batteries). Herein, employing the hydrothermal approach with solid Ni–Co spheres as precursors followed by the selenization process, selenide-rich bimetallic selenide spheres with a core–shell nanostructure were rationally designed and synthesized for use as the cathode electrode in superior BSH devices. The as-obtained (NiCo)9Se8/(NiCo)0.85Se (Ni–Co–Se) exhibits a high specific capacity of 164.44 mA h g−1 at a current density of 1 A g−1 with 85.72% capacity retention even after 5000 cycles at a current density of as high as 8 A g−1, suggesting its great promise in practical applications for BSH devices. By integrating activated carbon as the anode with the as-obtained bimetallic selenides as the cathode, an alkaline aqueous BSH device is fabricated and delivers a high energy density of 37.54 W h kg−1 at a high power density of 842.7 W kg−1. It is found that the excellent electrochemical performances can be ascribed to facile ion and electron transport pathways, high electrical conductivity and reliable structural robustness of the prepared selenides. Moreover, the synthetic strategy presented in this paper opens up an avenue to guide the synthesis of various anion doped bimetallic compounds towards high-performance energy conversion and storage devices.

Decomposition of a multiobjective optimization problem (MOP) into several simple multiobjective subproblems, named multiobjective evolutionary algorithm based on decomposition (MOEA/D)-M2M, is a new version of multiobjective optimization-based decomposition. However, it fails to consider different contributions from each subproblem but treats them equally instead. This paper proposes a collaborative resource allocation (CRA) strategy for MOEA/D-M2M, named MOEA/D-CRA. It allocates computational resources dynamically to subproblems based on their contributions. In addition, an external archive is utilized to obtain the collaborative information about contributions during a search process. Experimental results indicate that MOEA/D-CRA outperforms its peers on 61% of the test cases in terms of three metrics, thereby validating the effectiveness of the proposed CRA strategy in solving MOPs.

The experimental study on thermocapillary convection in liquid bridges of large Prandtl number has been carried out on Tiangong-2 in space. The purpose of these experiments is to study the oscillation instability of thermocapillary convection, and to discover and recognize the mechanism of destabilization of thermocapillary convection in the microgravity environment in space. In this paper, the geometry of a half-floating-zone liquid bridge is featured by the aspect ratio Ar and volume ratio Vr, and its influence on critical conditions of oscillatory thermocapillary convection is studied. More than 700 sets of space experiments have been finished. The critical conditions and oscillation characteristics of thermocapillary convection instability in the Ar–Vr parameter space have been fully obtained under microgravity conditions for the first time. It is found that the Ar–Vr parameter space can be divided into two regions of different critical conditions and oscillation characteristics: the region of low frequency oscillation, and the region of high frequency oscillation. More importantly, we obtain the complete configuration of these two stability neutral curves, and find that the low frequency mode is a ‘’ type curve. Based on this, we discuss the influence of heating rate on the oscillation mode. It is found that the heating rate affects the selection of critical mode, which results in a jump change of critical temperature difference. The findings of this study are helpful to better understand the critical modes and transition processes of thermocapillary convection in liquid bridges with different configurations.

The magnetic resonance imaging diagnosis and high-efficiency tumor targeting treatment are of notable importance for cancer therapy. In this study, starch-octanoic acid (ST-OA) micelles were successfully prepared to co-encapsulate the anti-tumor drug doxorubicin (DOX) and superparamagnetic iron oxide nanoparticles (SPIONs), taking advantage of the hydrophobic core of the core-shell micellar structure. Size distribution, morphology and in vitro release behaviors of micelles were investigated. In addition, magnetic properties and the anti-tumor theranostic performance were confirmed by conducting the cellular uptake, in vivo imaging and anti-tumor activity experiments. Therefore, co-encapsulation and specific delivery of the chemotherapeutic drug and contrast agent into tumor cells can realize the diagnosis and treatment of malignant tumor at the same time.

Oxidative stress is an important pathological mechanism for acute kidney injury (AKI). SS-31, as a mitochondria-targeted peptide with strong antioxidant activity, is a good candidate for the treatment of AKI. However, an efficient treatment of AKI requires frequent administration of SS-31, which is due to its poor specific biodistribution and low delivery efficiency. To overcome these deficiencies, we designed pH-responsive and AKI-kidney targeted nanopolyplexes (NPs) for effectively delivering SS-31, which is new frontier for formulation of HA and CS. NPs are electrostatically complexed using anionic hyaluronic acid and cationic chitosan as materials, which could increase the accumulation in injured areas and uptake into CD44-overexpressed cells. Electrostatic balance of NPs is broken in low pH environment of lysosomes to allow SS-31 releasing and subsequently targeting to mitochondria to represent therapeutic effect. In vitro studies indicate that NPs exhibited higher antioxidative and antiapoptotic effects as compared with free SS-31. AKI mouse model suggests that NPs have significantly higher therapeutic efficiency than bare SS-31. It was found that NPs had excellent ability to decrease oxidative stress, protect mitochondrial structure, reduce inflammatory response, reduce apoptosis and necrosis of tubular cells after intravenious administration. Overall, the results suggest that the NPs have significant potential to enhance the specific biodistribution and delivery of SS-31, therefore have good effects on reducing oxidative stress and inflammation, preventing tubular apoptosis and necrosis. We believe NPs are effective delivery system for AKI treatment in clinical application.

Cationic anticancer peptides, which can induce tumor cell immunogenic death and further promote systemic tumor-specific immune responses, have offered a promising solution to relieve the tumor immunosuppressive microenvironment. However, peptide drugs are easily degraded and lack of targeting ability when administered systemically, leading to limitations in their applications. Herein, we report a pH and thermal dual-sensitive bovine lactoferricin-loaded (one of the most widely studied cationic anticancer peptides) nanoparticles, which simultaneously exhibited antitumor and immune cell activated effects when applied with microwave thermotherapy, an auxiliary method of immunotherapy. The bovine lactoferricin could be delivered to the tumor site by nanoparticles, be immediately released from nanoparticles in the acidic environment of lysosomes and the thermal condition caused by microwave radiation, and ultimately induce tumor apoptosis with the release of damage-associated molecular patterns (DAMPs). It is worth noting that the strategy of bovine lactoferricin-loaded nanoparticles intravenous injection combined with local microwave thermotherapy not only showed excellent efficacy in relieving tumor growth but also resulted in strong antitumor immunities, which was due to the released bovine lactoferricin under stimulating conditions, and the pool of tumor-associated antigens generated by tumor destruction. In conclusion, this work presents a strategy for tumor treatment based on dual-sensitive bovine lactoferricin-loaded nanoparticles combined with microwave thermotherapy, which may provide a solution for cationic anticancer peptides delivery and improving antitumor immune responses.

This paper is an investigation on oscillation characteristics and transition routes of thermocapillary convection in an annular liquid pool in the space experiment carried out on SJ-10 recoverable scientific experiment satellite. Thermocapillary convection caused by non-uniformity of surface tension and the instability problem of the convection are introduced, and the measurement by thermocouples has been analyzed in detail. Through the relationship between the critical condition of start-oscillation in thermocapillary convection and the volume ratio, and the relationship between the oscillation frequency and the volume ratio, transition processes from steady flow to oscillatory flow and then to bifurcation are investigated. In addition, the acting mechanism of thermocapillary force has been discussed comparing with buoyant-thermocapillary convection on the ground.

Improvement of the sensitivity and selectivity is important in the development of an analytical method. Herein, we propose a differential photoelectrochemical (PEC) sensor to hydrogen peroxide based on the catalytic activity difference between two zeolitic imidazolate framework (ZIF) surface coatings. In the sensing and reference photoelectrodes, ZIF-67 and ZIF-8 films were grown on the surface of carboxylated carbon nanotubes-graphite-like carbon nitride/TiO2 nanotube array, respectively. The molecular sieve effect of ZIF-8 and ZIF-67 coatings can prevent the diffusion of molecules with size larger than the pores in coating layers (e.g. ascorbic acid), improving the selectivity of the PEC sensor to H2O2. The sensing photoelectrode offers higher sensitivity to H2O2 than the reference one due to the excellent catalytic activity of ZIF-67. The interference from the surfaces of the sensing and reference photoelectrodes can be eliminated effectively by the differential strategy, enhancing further the selectivity, reliability and stability of the sensor. Under optimized conditions, the as-prepared differential PEC sensor was applied to the detection of H2O2 with limit of detection of 1.5 nM, exhibiting high sensitivity and anti-interference ability.

Thermocapillary convection has always been one of the most important research topics in microgravity fluid physics. A space experimental study on the thermocapillary convection in an open annular liquid pool – a typical thermocapillary flow system – has been conducted on the SJ-10 satellite of China. This space experiment has observed the spatial temperature distribution of the liquid free surface using an infrared thermal imager, obtained the flow pattern transition process, analysed the oscillation characteristics and revealed the instability mechanism of themocapillary convection. The shape effects on the flow instability are researched by changing the volume ratio, Vr, which denotes the ratio of the liquid volume to the volume of the cylindrical gap between the walls. The volume ratio effect has been focused on for the first time. For a certain volume ratio, the flow pattern would transform from the steady state to the oscillation state accompanied by directional propagating hydrothermal waves with increasing temperature difference. In addition, the significant influences of the volume ratio on the critical conditions and wavenumber selection have been analysed in detail.

Spinal cord injury (SCI) routinely causes the immediate loss and disruption of neurons followed by complicated secondary injuries, including inflammation, oxidative stress, and dense glial scar formation. Inhibitory factors in the lesion scar and poor intrinsic neural regeneration capacity restrict functional recovery after injury. Minocycline, which has neuroprotective activity, can alleviate secondary injury, but the long-term administration of this drug may cause toxicity. Polysialic acid (PSA) is a large cell-surface carbohydrate that is critical for central nervous system development and is capable of promoting precursor cell migration, axon path finding, and synaptic remodeling; thus, PSA plays a vital role in tissue repair and regeneration. Here, we developed a PSA-based minocycline-loaded nanodrug delivery system (PSM) for the synergistic therapy of spinal cord injury. The prepared PSM exerted marked anti-inflammatory and neuroprotective activities both in vitro and in vivo. The administration of PSM could significantly protect neurons and myelin sheaths from damage, reduce the formation of glial scar, recruit endogenous neural stem cells to the lesion site, and promote the regeneration of neurons and the extension of long axons throughout the glial scar, thereby largely improving the locomotor function of SCI rats and exerting a superior therapeutic effect. The findings might provide a novel strategy for SCI synergistic therapy and the utilization of PSA in other central nervous system diseases.

Photodynamic therapy (PDT) and photothermal therapy (PTT) are effective cancer treatments, and photosensitizers play the most important role in the treatment. However, photosensitizers are insufficient for in vivo tumor treatment. Herein, we develop a small molecule fluorophore Cy-HPT as a novel photosensitizer, which possesses the advantages of near-infrared (NIR) emission, high photothermal conversion efficiency and high singlet oxygen generation efficiency. Moreover, a nanoplatform of HSA@Cy-HPT was synthesized by self-assembly of Cy-HPT and human serum albumin (HSA) in aqueous solution. Compared to Cy-HPT, HSA@Cy-HPT possesses more stable spectral properties, enhances the effect of PDT/PTT, and exhibits more satisfactory in vivo metabolism. HSA@Cy-HPT demonstrates outstanding tumor targeting in subcutaneous tumor xenograft models owing to its enhanced permeability and retention in tumor tissue. Furthermore, HSA@Cy-HPT was successfully utilized in tumor xenograft models and tumor tissue growth was clearly inhibited without any regrowth, extending survival rate of the models. Also, no distinct damage of the normal tissue of tumor xenograft models was observed using hematoxylin & eosin staining. This study presents a promising therapeutic agent for the synergetic PDT and PTT cancer treatment.

Multiple drug resistance and the increase in the appearance of superbugs together with the exceedingly scant development of new potent antibiotic drugs pose an urgent global medical threat and imminent public security crisis. In the present study, we fabricated well-dispersed tocopherol polyethylene glycol succinate (TPGS)-capped silver nanoparticles (AgNPs) of about 10 nm in size. The hollow structure of the TPGS-capped AgNPs (TPGS/AgNPs) was confirmed and applied to load antibiotics. The TPGS/AgNPs proved to be able to cross the bacterial cell wall and penetrate into bacteria, thereby delivering more of the antibiotic to the interior of bacteria and thus enhancing the in vitro antibacterial effect of the antibiotic, even overcoming the drug-resistance in drug-resistant E. coli and Acinetobacter baumannii. It was found that the TPGS modification in the TPGS/AgNPs could decrease the activity of the efflux pumps AdeABC and AdeIJK in drug-resistant Acinetobacter baumannii via inhibiting the efflux pump genes adeB and adeJ, thus increasing the accumulation of the delivered antibiotic and overcoming the drug-resistance. Tigecycline delivered by TPGS/AgNPs could effectively antagonize drug-resistance in an acute peritonitis model mice, thereby increasing the survival rate and alleviating the inflammatory response. TPGS/AgNPs were developed as a novel and effective antibiotic delivery system and TPGS was demonstrated to have great potential as a pharmaceutical excipient for use in drug-resistant infection therapy.

A simple, low-cost and label-free strategy for detecting lithocholic acid (LCA) was designed at the liquid crystals (LCs)/aqueous interface via competitive host-guest inclusion. In this method, sodium dodecyl sulfate (SDS) was initially adsorbed on the fluid interface and induced LCs to adopt the homeotropic ordering. Inclusion complexation of SDS and β-cyclodextrin (β-CD) disturbed interaction between LCs and SDS and evoked LCs to keep a tilted alignment. When injecting LCA into the mixed solution of SDS and β-CD, SDS excluded from the cavity of β-CD by competitive host-guest inclusion and could be re-adsorbed at the LCs/aqueous interface, resulting in the orientational transition of LCs from tilted to homeotropic state. Correspondingly, a bright-to-dark optical response was observed under polarized optical microscope (POM). The as-prepared LCs-based sensor could detect LCA as low as about 2 μM in aqueous solution. Moreover, the practicability of the approach was validated by monitoring the known amount of LCA in human urine. This work offers an appealing approach for the detection of LCA which has a great potentiality in clinical diagnosis.

The sluggish redox kinetic and the severe shuttle effect remain the key issues for the application of lithium–sulfur batteries, resulting in low sulfur utilization and rapid capacity fading. Herein, a nanostructured VS4 anchored on defect-rich carbon nanofibers (CNF-VS4) was coated on the commercial separator as both physical blocks to mitigate the shuttle effects and as an electrocatalyst to enhance the reaction kinetics of polysulfides/Li2S. Besides, polar nanostructured VS4 shows a high affinity to polysulfides, and conductive CNF network serves as “second collector” to trap and reutilize the active materials. The functional coating layer also provides rich defects for the dispersion and stabilization of Li2S. When the CNF-VS4 functional separator based on a high-sulfur content (80 wt%) cathode was applied in Li–S batteries, a high initial capacity of 1135 mA h g−1 at 0.2C and a superior rate capacity of 780 mA h g−1 at 2C were achieved. Even under a higher rate (5C), it still delivered a stable capacity of 300 mA h g−1 over 1000 cycles with a high coulombic efficiency of 95%.

Twitter spam classification is a tough challenge for social media platforms and cyber security companies. Twitter spam with illegal links may evolve over time in order to deceive filtering models, causing disastrous loss to both users and the whole network. We define this distributional evolution as a concept drift scenario. To build an effective model, we adopt K-L divergence to represent spam distribution and use a multiscale drift detection test (MDDT) to localize possible drifts therein. A base classifier is then retrained based on the detection result to gain performance improvement. Comprehensive experiments show that K-L divergence has highly consistent change patterns between features when a drift occurs. Also, the MDDT is proved to be effective in improving final classification result in both accuracy, recall, and f-measure.

Ratiometric electrochemical sensors can provide a relatively accurate analysis of target analytes due to their self-calibration function. Herein, we report a simple ratiometric strategy for achieving the electrochemical detection of Cd(ii), Hg(ii), Pb(ii) and Zn(ii), as well as multiple cancer biomarkers by using metal sulfide nanoparticles as signal tags. A conductive polymer film of poly(2-amino terephthalic acid) (ATA) was electrochemically produced on a glassy carbon electrode (GCE) and doped with carbon nanotubes (CNTs) and mercaptosuccinic acid (MSA). Using Bi(iii) as an enhancer and internal reference in anodic stripping voltammetry, the MSA-CNT-ATA/GCE exhibited sensitive and distinguishable voltammetric responses to Cd(ii), Hg(ii), Pb(ii) and Zn(ii), with detection limits of 0.13, 0.49, 0.16 and 0.089 μg L-1, respectively. By using CdS, HgS, PbS and ZnS labeled secondary antibodies as the signal tags, alpha-fetoprotein, carbohydrate antigen 19-9, carbohydrate antigen 125, and carcinoembryonic antigen were determined simultaneously according to the amounts of metal sulfide in the sandwich-type complexes, with detection limits of 0.11 pg mL-1, 0.68 mU mL-1, 1.4 mU mL-1 and 0.23 pg mL-1, respectively. This ratiometric approach has a wide scope in the electrochemical detection of heavy metal ions as well as immunoassays with metal ions serving as signal tags.

A liquid crystals (LCs)-based sensing platform was constructed for simple, convenient, inexpensive and label-free detection of α-amylase, associated with disruption of host-guest interaction between sodium dodecyl sulphate (SDS) and β-cyclodextrin (β-CD). In the presence of SDS/β-CD solution, a bright optical image was observed corresponding to the tilted anchoring of LCs at the aqueous/LCs interface. While a black optical appearance was captured when the pre-incubated mixture containing SDS/β-CD complex and ≥0.0001 mg/mL α-amylase was transferred onto the fluid interface. The reason for this difference is that α-amylase could hydrolyze β-CD and subsequently destroy the host-guest interaction between SDS and β-CD. SDS molecules escaping from the cavity of β-CDs were adsorbed at the aqueous/LCs interface, which evoked the homeotropic state of LCs. In the case of α-amylase below 0.0001 mg/mL, a bright optical image was observed. Based on these, detection of α-amylase could be achieved and its detection limit was ∼0.0001 mg/mL (15 U/L). Moreover, this sensing platform was successfully utilized to monitor α-amylase in the body fluids, such as urine and saliva, indicating its potentiality in the relevant clinical diagnosis.

In recent years, the Chinese government is making great efforts to develop electric vehicle (EV) technologies to reduce carbon emissions and to protect the environment. A large number of EVs and facilities, such as charging stations (CSs), battery swapping stations (BSSs), and central charging stations (CCSs), have been deployed. However, a huge number of EVs connecting into the power grid may cause problems, such as voltage fluctuation etc. Meanwhile, the peak demand for charging will also lead to an increase in the cost of deployment of charging infrastructure. A price-based demand response (DR) program can be used to achieve goals, such as cost savings and reduction of the peak demand for charging. But to maximize the charging service capacity while minimizing the total cost is a challenging task as it is usually a tripartite game between the government, EV owners, and EV battery service providers. We considered it as a multi-objective optimization problem. First, a battery-swapping cost model is designed to describe the objective problem. It includes a battery demand model, a DR-based subsidy cost model and a charging cost model. Then, we leverage a covariance matrix adaption evolution strategy (CMAES)-based algorithm to deal with the multi-objective high dimension optimization problem and achieve the goal of maximizing the charging service capacity while minimizing the total cost. The experimental results confirm that the peak demand for battery swapping service can be reduced effectively and the total cost can be reduced by nearly 12% with our optimized subsidy strategy. Furthermore, the standard deviation evaluation results confirm the stability and the effectiveness of the proposed algorithm.

Lithium–sulfur (Li–S) batteries are widely regarded as some of the most promising next-generation energy storage systems due to their cost advantage and high theoretical energy density. However, the shuttle effect arising from the dissolution of polysulfides into organic electrolyte, the insulating nature of sulfur and their discharge products severely restrict the development of high-energy density Li–S batteries. Herein, a porous organic framework containing diketopyrrolopyrrole (DPP) building blocks is reasonably designed and it serves as a shuttle-inhibiting layer to bifunctionally increase the physical and chemical trapping of lithium polysulfides. The frameworks were synthesized through a bottom-up approach, allowing precise control of the network design at the molecular level. As a result, the framework-derived microscale networks with polar units effectively hinder the shuttle effect of polysulfides and promise excellent electrochemical performances with regard to improving kinetics and long-term cycling stability of Li–S batteries. DFT calculations demonstrate the charge transfer (CT) behavior and favorable binding energy between the DPP units and lithium polysulfides. This work not only provides a novel strategy to fabricate a bifunctional modified separator for high-performance Li–S batteries, but also inspires us to further develop advanced materials for emerging energy storage applications.

A dandelion algorithm (DA) is a recently-proposed intelligent optimization algorithm and shows an excellent performance in solving function optimization problems. However, like other intelligent algorithms, it converges slowly and falls into local optima easily. To overcome these two flaws, a dandelion algorithm with probability-based mutation (DAPM) is proposed in this paper. In DAPM, both Gaussian and Levy mutations can be used interchangeably according to a given probability model. In this paper, three probability models are discussed, namely linear, binomial, and exponential models. The experiments show that DAPM achieves better overall performance on standard test functions than DA.

Effective treatment for acute lung injury (ALI) is in high demand. Lung-targeted ternary nanoparticles containing anti-intercellular adhesion molecule-1 (ICAM-1) antibody-conjugated simvastatin-loaded nanostructured lipid carrier (ICAM/NLC), protamine (Pro), and angiopoietin-1 (Ang-1) gene (ICAM-NLC/Pro/Ang) were developed for ALI therapy. The ternary nanoparticles with different weight ratios of ICAM-NLC to Ang-1 gene were prepared via charge interaction. The anti-ICAM-1 antibody-conjugated ternary nanoparticles exhibited higher cellular uptake and transfection efficiency (from 26.7% to 30.9%) in human vascular endothelial cell line EAhy926 than the non-targeted control. The largest size of ICAM-NLC/Pro/Ang (357.1 nm) was employed for further study, which significantly up-regulated in vitro and in vivo Ang-1 protein expression. In vivo i.v. administration of ICAM-NLC/Pro/Ang (357.1 nm) significantly attenuated pulmonary TNF-α and IL-6 levels, inflammatory cell infiltration, and led to positive histological improvements in lipopolysaccharide-induced ALI mice. Collectively, the ICAM-NLC/Pro/Ang that co-delivered simvastatin and Ang-1 gene may represent a potential treatment modality for ALI.

Glutathione (GSH) is of significance in human pathology due to its many cellular functions. γ-Glutamyl transpeptidase (γ-GT) plays a key role in the balance of GSH by breaking down extracellular GSH. In this study, we proposed a novel strategy for sensitive and selective detection of GSH based on LC sensing platform coupled with its inhibition of γ-GT. The γ-GT cleavable surfactant, dodecyl N-ethanamide N, N, N-trimethylammonium bromide (DAA), was synthesized and utilized to decorate the aqueous/LC interface. A black optical image of LCs was observed due to formation of the self-assembled DAA monolayer at the interface. Subsequently, the optical response of LCs returned to bright appearance after transferring γ-GT to the DAA-laden interface because DAA could be enzymatically hydrolyzed by γ-GT and the monolayer was disrupted. Interestingly, LCs remained dark images after the DAA-decorated interface in contact with the pre-incubated GSH and γ-GT. The detection limit of GSH reached 1 pg/mL, which demonstrates high competitiveness with the current assays. The detection mechanism of GSH was explained by Isothermal titration calorimetry (ITC) measurements and Fourier transform infrared (FTIR) spectroscopy. This work presents an appealing route to achieve ultrasensitive detection of GSH according to its hydrolysis by γ-GT and the as-prepared simple and robust LC-based sensing platform has potentials in the diagnosis of GSH-related diseases (e.g. cancer, liver damage, and malignant neoplasms).

Fabrications and applications of luminescent films have been an interesting and important challenge within the realm of academia and industry. Herein, a novel fluorescence-based strategy for the H2O2 detection has been developed by fabrication of stabilized, thin, transparent, and luminescent films composed of europium-containing polyoxometalates (Eu-POM) and environmentally friendly chitosan (CS) via a facile solution casting approach. In comparison with pure Eu-POM, enhanced fluorescent properties are obtained from the as-prepared Eu-POM/CS films in terms of prolonged fluorescence lifetime and a remarkable fluorescent quenching effect in the presence of hydrogen peroxide (H2O2). The fluorescence intensity of Eu-POM/CS films exhibits a linear correlation in response to the H2O2 concentration over a wide range of 1.1–66 μM, with a detection limit of 0.11 μM. Furthermore, the fluorescent films display a high detection selectivity which are capable of differentiating hydrogen peroxide (H2O2) from the interfering species, such as sugars, l -amino acids, and other metabolites. All these advances towards the development of Eu-POM/CS films open up new applications for luminescent films, but most importantly, they can help in the far-reaching technological implementations of a simple, cost-effective method for the detection of H2O2 in many fields.

The lithium sulfur battery is regarded as a promising energy solution because of its high energy density. However, the insulating nature and large volumetric expansion of sulfur and the high solubility of polysulfides restrict their practical applications. Here carbon nanotube (CNT)-induced yolk–shell carbon nanopolyhedra, with Co–N-doping, is used as host material for sulfur. The CNTs are used to create a conductive network which interweaves each carbon polyhedron and induces the formation of a yolk–shell structure during the sulfur melt-diffusion process due to the “perforation effect”. The CNT-connected Co–N-doped carbon nanopolyhedra containing sulfur yolk–shell structure (S@Co–N–C/CNTs-0.5) can achieve a capacity of 712.2 mAh g–1 at 1675 (1 C) mA g–1 after 300 cycles and 511.8 mAh g–1 at 3350 (2 C) mA g–1. The outstanding performance is attributed to the new paradigm, S@Co–N–C/CNTs-0.5 yolk–shell structure, which creates a conductive network allowing for improved electron transport and convenient ele...

Signal amplification for electrochemiluminescence (ECL) has conventionally been achieved by employing effective matrixes that can accelerate the electrochemical redox processes or carry more electr...

Herein, we developed a smartphone-based ratiometric resonance light scattering (RLS) device for portable field analysis and immunoassay. The RLS signal was detected by the camera in a smartphone controlled by a user-edited APP software. Except the smartphone, the total cost of the detection system itself is about 60 $, including a laser pointer and battery, a twin cuvette, a collective lens, and outside box. By using the RLS brightness ratio between the sample and reference channels in the twin cuvette as the signal indicator, the baseline drifts due to the variations in incident light intensity, ambient temperature, and shooting parameters of camera, can be eliminated efficiently. A new brightness indictor, (R − R0)/(Rmax − R), was proposed to linearize the calibration curve. Where R and R0 are the rightness ratio in sample and blank, Rmax is the maximum averaged brightness ratio, respectively. The applicability of the portable RLS device was demonstrated by the field analysis for Pb2+ in environmental water samples, using [CTA]2PbI4］(CAT = cetyltrimethyl ammonium) as the luminophore. The limit of detection for Pb2+ is 0.7 μg L−1. By using PbS nanoparticles conjugated second antibody as the signal tag, the RLS method was applied in immunoassay to determine alpha fetoprotein with the limit of detection of 0.1 pg mL−1. This smartphone-based ratiometric RLS device offers the advantages of good portability, low cost, high sensitivity and reliability.

The in vivo bio-behaviors and biosafety of nanoparticles were demonstrated to be closely correlated with particle sizes, which illustrated whether they could be used as the effective drug delivery carriers. Though tumor penetration capabilities of the small pore sized-mesoporous silica nanoparticles (MSNs) were reported to be in a particle size-dependent manner, the size effects of large pore sized-MSNs on the safe and effective cancer resistance treatment, especially at sub-50 nm, were not explicitly evaluated. In this study, we fabricate the 20 nm and 50 nm MSNs, and aim at investigating their difference in tumor accumulation, penetration, retention and toxicity both in vitro and in vivo. Our results showed that these two particle sized-MSNs possessed the excellent tumor penetration capabilities both in resistant human hepatocellular carcinoma cells-cultured spheroids and in the corresponding xenograft mice models, but the 50 nm MSNs seemed to have the better tumor accumulation and retention effects than the 20 nm MSNs. Moreover, the 50 nm MSNs displayed the lower toxicities than the 20 nm MSNs whatever on resistant cancer cell lines or on zebrafish embryos, indicating the greater systematic biosafety. In a word, our data provide the evidence that selection of the large pore-sized MSNs at the appropriate particle size (not the smaller the better) as bio-macromolecule nanocarriers will play a key role in the safe and effective treatment against cancer resistance.

The development of space experiment payload for studying thermocapillary convection in the liquid bridge with large Pr number on TG-2 space laboratory as well as the experiments are presented in detail in this paper, and the objectives of the space experiments are confirmed. The functions of the payload are analyzed, and the technical and engineering specifications are determined. Detailed designs and experimental verifications are performed on the structure of liquid bridge columns, the method of bubble removing in the liquid, the bridge cleaning system, the accurate control of aspect ratio and volume ratio, and the high-sensitivity measurement of fluid temperature. Matching experiments on the ground according to space experiment properties are carried out, 5cSt silicone oil is selected as the fluid medium in space experiments. And the states of liquid bridge and temperature oscillation signals obtained from space experiments are presented at the end of this paper. Specific summarizations and discussions to the experiment project on fluid science in space are conducted in this paper, which will provide a useful reference for scientists participating space experimental research in the future.

Text classification is a fundamental and important area of natural language processing for assigning a text into at least one predefined tag or category according to its content. Most of the advanced systems are either too simple to get high accuracy or centered on using complex structures to capture the genuinely required category information, which requires long time to converge during their training stage. In order to address such challenging issues, we propose a dynamic embedding projection-gated convolutional neural network (DEP-CNN) for multi-class and multi-label text classification. Its dynamic embedding projection gate (DEPG) transforms and carries word information by using gating units and shortcut connections to control how much context information is incorporated into each specific position of a word-embedding matrix in a text. To our knowledge, we are the first to apply DEPG over a word-embedding matrix. The experimental results on four known benchmark datasets display that DEP-CNN outperforms its recent peers.

As it is difficult to directly share data among different organizations, data federation brings new opportunities to the data-related cooperation among different organizations by providing abstract data interfaces. With the development of Cloud computing, organizations store data on the Cloud to achieve elasticity and scalability for data processing. The existing data placement approaches generally only consider one aspect, which is either communication cost or time cost, and do not consider the features of jobs that process the data. In this paper, we propose an approach to enable secure data processing on the Cloud with the data from different organizations. The approach consists of a data federation platform for secure data processing on the Cloud named FedCube and a greedy data placement algorithm that creates a plan to store data on the Cloud in order to achieve multiple objectives based on a cost model. The cost model is composed of two objectives, i.e., reducing both monetary cost and execution time. We present an experimental evaluation by comparing our data placement algorithm with the existing methods based on the data federation platform. The experiments show that our proposed algorithm significantly reduce the total cost (up to 69.8%).

A crane system often works in a complex environment. Traditional system identification methods are difficult to accurately model crane system identification's real dynamic performance, whether online or offline. Therefore, a Data-driven model predictive control (D-MPC) algorithm is proposed in this paper. Based on Bayesian optimization, the crane's local linear dynamic model is learned to improve the rapidly anti-swing and precise positioning. By collecting data through closed-loop experiments and using Bayes to construct the Gaussian model for guiding learning, the controller parameters and prediction model with the best closed-loop performance can be found. Simulation results show that we explicitly find the dynamics model that produces the best control performance for the actual system, and the method can quickly suppress the swing and realize the accurate trolley positioning. The results verify the proposed control algorithm's effectiveness, feasibility and superior performance of the proposed method by comparing it with double-closed-loop proportional–integral– derivative (PID).

Boron nitride nanosheets (BNNSs) have gained significant attraction in energy and environment fields because of their two-dimensional (2D) nature, large band gap and high thermal/mechanical performance. However, the current low production efficiency of high-quality BNNSs is still a bottleneck limiting their applications. Herein, based on sonication-assisted liquid-phase exfoliation, we demonstrated a rapid, high-efficient and scalable production strategy of BNNSs and documented the effects of a spectrum of exfoliation factors (e.g., ultrasonic condition, solvent and bulk material feeding) on the yield of BNNSs. A record of yield of 72.5% was achieved while the exfoliated BNNSs have few-layer and defect-free feature. Thanks to the Lewis acid sites of the boron atoms, the BNNSs can interact with the polysulfide anions in liquid electrolyte and also can facilitate the uniform lithium deposition, which finally endow a lithium-sulfur (Li-S) battery with long life. This work provides a facile and rapid strategy for large scale preparation of high-quality BNNSs, also contributes a long-life strategy for dendrite-free Li-S battery, opens new avenues of BNNSs in energy application.

Near-infrared electrochemiluminescence (NIR ECL) luminophores are strongly anticipated in ECL bioimaging and spectrum-resolved multiplexing assays. Herein, bovine serum albumin-stabilized Ag nanoclusters (BSA-Ag NCs) are demonstrated promising NIR ECL performance, exhibiting strong anodic ECL spectrum peak at 904 nm in aqueous medium. The ECL intensity of BSA-Ag NCs-triethanolamine system was enhanced 3.2 times by adding TiO2 nanoparticles as co-reactant accelerator. In a spectrum-resolved triplex-color ECL multiplexing immunoassay, CdSe NCs, CdTe NCs and BSA-Ag NCs were used as the ECL tags, carbohydrate antigen 125 (CA125), carbohydrate antigen 19–9 (CA19-9) and cardiac troponin I (cTnI) were chosen as model analytes. The ECL peaks of three antigen-NCs pairs were simultaneously measured via one ECL potential scan. The composite of carbon nanotubes-TiO2 nanoparticles-chitosan was served as the conductivity and co-reactant accelerators, enhancing the ECL intensity by 16 folds. With the integral intensity over the ECL peaks as the analytical signal to improve further the signal-to-noise ratio, the limits of detection were 0.035 mU mL−1 for CA125, 0.087 mU mL−1 for CA19-9, and 0.016 pg mL−1 for cTnI, respectively.

Fuzzy control is an important control algorithm and is applied in many areas. In this paper, scientometric analysis is applied to present a systematic overview of the research topics and current status of the fuzzy control. 13651 articles and 91885 relevant references from 2010 to 2019 are investigated from the Web of Science Core Collection. The most influential authors and journals are presented. The disciplines and topics of fuzzy control research are identified. The visual network of knowledge structure of fuzzy control is established. The deeper researches of citation bursts, centrality and sigma are made. The results of this research provide the practitioners a better understanding of fuzzy control and help the researchers do relevant further study.

A smartphone-based ratiometric fluorescence device was designed to monitor the reaction kinetic process under vigorous mixing conditions, demonstrated by the hydrolysis of Cs4PbBr6 nanocrystals (NCs). In the presence of trace water, part of Cs4PbBr6 NCs (non-fluorescent) was converted to CsPbBr3 NCs (strong fluorescent). Using anthracene as the reference fluorophore, the brightness ratio of the green (from CsPbBr3 NCs) to blue (from anthracene) components in the fluorescence image which was recorded in situ by the smartphone camera was measured as the signal for kinetic analysis. It was shown that the water-triggered conversion reaction from Cs4PbBr6 NCs to CsPbBr3 NCs follows the pseudo-second-order kinetic model in the early rapid hydrolysis stage (up to 4 min). With increasing water content, the hydrolysis of Cs4PbBr6 NCs is promoted to yield more CsPbBr3 NCs, which was used to determine trace water in n-hexane, dichloromethane, and toluene with detection limits of 0.031, 0.043, and 0.057 μL mL−1, respectively. The device offers the advantages of portability and low cost for rapid field determination of trace water in hydrophobic organic solvents.