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In the present study, maltotetraose was prepared by enzymatic hydrolysis of maltodextrin. The hydrolysates were further separated and purified using a simulated moving bed after essential pretreatments. For the first time, this method offers a continuous preparation process to produce high-purity maltotetraose. In addition, the purity and stability of the prepared maltotetraose product were analysed. The maltotetraose product showed a purity of 81.32 %, which is the highest reported purity derived from the continuous process. Moreover, the maltotetraose product was extremely stable during storage and thermal processing and exhibited unique and excellent antibacterial activity against Erwinia sp., which cause soft rot in fruits and plants. The results indicate that the maltotetraose product shows great potential to serve as a functional sugar source with high safety and no pollution.

In this work, 1,1,2,2-tetra(4-carboxylphenyl)ethylene (H4TCPE) was selected as the guest and incorporated into a Eu/AMP ICP host to establish a "lab-on-an-AIE@Ln/ICP" sensor array for identifying and sensing environmental antibiotics simultaneously. First, on the basis of a theoretical study of the antenna effect and reductive photoinduced charge transfer between the as-prepared H4TCPE@Eu/AMP ICPs and antibiotics, respectively, the response from the sensitized time-resolved fluorescence of the host and the unique aggregation-induced emission (AIE) of the guest were selected as the main sensing elements for the sensor array. With the regulation of pH, the diverse fluorescence responses for antibiotics with either structural differences (flumequine, oxytetracycline, and sulfadiazine) or structural similarities (oxytetracycline, tetracycline, and doxycycline) were recorded and processed by principal component analysis; systematic analysis of environmental antibiotics was therefore realized. Encouraged by the superior anti-aggregation-caused quenching effect of H4TCPE@Eu/AMP ICPs on the test strip, the distinct fluorescence color changes of the "lab-on-an-AIE@Ln/ICP" sensor array were further explored with the aid of smartphones. The fingerprinting pattern of the sensor array on test paper eventually holds great potential for the point-of-use systematic analysis of environmental antibiotics even in complicated real samples.

Soft electronics featuring exceptional mechanical compliance and excellent electrical performance hold great promise for applications in soft robotics, artificial intelligence, bio-integrated electronics, and wearable electronics. Intrinsically stretchable and conductive materials are crucial for soft electronics, enabling large-area and scalable fabrication, high device density, and good mechanical compliance. Conducting polymers are inherently stretchable and conductive. They can be precisely synthesized from vastly available building blocks, and thus they provide a fruitful platform for fabricating soft electronics. However, amorphous bulk-phase conducting polymers typically exhibit poor mechanical and electrical characteristics. Consequently, it is highly desirable to develop novel engineering approaches to overcome the intrinsic limitations of conducting polymers. In recent years, numerous engineering strategies have been developed to enhance their performances in soft electronic devices via constructing various nanostructures. In this review, we first summarize several unique methodologies to fabricate conducting polymer-based nanostructures. We then discuss how nanoscale engineering approaches can improve several crucial parameters, including electrical conductivity, stretchability, sensitivity, and self-healing property of conducting polymers. Moreover, we also discuss device-level integration of conducting polymer-based nanostructures with other materials for applications in skin-inspired electronics and bio-integrated electronics. Finally, we provide perspectives on challenges and future directions in engineering nanostructured conducting polymers for soft electronics.

Characterizing regulatory effects of genomic variants in plants remains a challenge. Although several tools based on deep-learning models and large-scale chromatin-profiling data have been available to predict regulatory elements and variant effects, no dedicated tools or web services have been reported in plants. Here, we present PlantDeepSEA as a deep learning-based web service to predict regulatory effects of genomic variants in multiple tissues of six plant species (including four crops). PlantDeepSEA provides two main functions. One is called Variant Effector, which aims to predict the effects of sequence variants on chromatin accessibility. Another is Sequence Profiler, a utility that performs ‘in silico saturated mutagenesis’ analysis to discover high-impact sites (e.g., cis-regulatory elements) within a sequence. When validated on independent test sets, the area under receiver operating characteristic curve of deep learning models in PlantDeepSEA ranges from 0.93 to 0.99. We demonstrate the usability of the web service with two examples. PlantDeepSEA could help to prioritize regulatory causal variants and might improve our understanding of their mechanisms of action in different tissues in plants. PlantDeepSEA is available at http://plantdeepsea.ncpgr.cn/., Graphical Abstract Graphical AbstractPlantDeepSEA integrates ATAC-seq data and genomic sequences based on a deep learning approach to predict the regulatory effects of genomic variants in multiple tissues of six plant species. It provides two main functions: "Variant Effector" to annotate the effects of genomic variants on chromatin accessibility, and "Sequence Profiler" to discover high-impact sites.

An image analysis-based two-stage process parameters tuning and Surface Roughness (SR) estimation algorithm is proposed for the laser cleaning application. A Cartesian coordinate robot is utilized to collect image and implement cleaning. Before cleaning, in order to tune the proper laser parameters, first, the environment lighting is controlled for the metal image collection. Second, lots of classification features are computed for the images above. The Gray-Level Co-occurrence Matrix (GLCM) texture features, the concavo-convex region features, the histogram symmetry difference feature, and the imaging thermophysical property features are computed. Third, the initial laser parameters are created randomly and an iteration computation is performed: a Support Vector Machine (SVM) is used to forecast the cleaning effect; its inputs include the classification features and the initial laser parameters; its output is the cleaning effect degree. If the SVM output cannot fulfill user’s demand, the laser parameters will be updated randomly. This iteration will be implemented constantly until the SVM output becomes valid. Then the laser cleaning will be performed. When estimating SR for the cleaned metal, multiple image features are calculated for the images after cleaning. The features include the Tamura coarseness, some GLCM features, and the convex region feature. To improve the prediction precision, different feature combinations are used for different cleaning effects. The linear function and the 3-order polynomial function are considered for the SR estimation. After tests, the accuracies of SVM, the SR prediction function, and the integrated SR control and estimation algorithm can be 90.0%, 80.0% and 80.0% approximately.

The reduced graphene oxide-supported copper (Cu@rGO) nanocomposite was introduced to improve the electrochemical properties of La0.7Mg0.3Ni2.8Co0.5 alloy electrodes. Experimental results show that adding Cu@rGO nanocomposite with mass fractions of x wt% (x = 0, 3, 6 and 9) to the alloy electrodes provides electrodes with maximum discharge capacities of 368.9 mAh/g (x = 0), 373.2 mAh/g (x = 3), 407.3 mAh/g (x = 6) and 398.6 mAh/g (x = 9), and high-rate dischargeabilities at a discharge current density of 1200 mA/g of 40.5% (x = 0), 64.0% (x = 3), 82.0% (x = 6) and 76.0% (x = 9). The addition of Cu@rGO nanocomposite also provides alloy electrodes with hydrogen diffusion coefficients of 3.7 × 10−10 cm2/s (x = 0), 4.1 × 10−10 cm2/s (x = 3), 4.2 × 10−10 cm2/s (x = 6) and 4.0 × 10−10 cm2/s (x = 9). Clearly, the addition of 6 wt%Cu@rGO nanocomposite not only increases the electrochemical capacity of La0.7Mg0.3Ni2.8Co0.5 alloy electrodes, but also improves their electrochemical kinetic properties.

In this study, the isotopic composition (δ13C and δ15N), total organic carbon content, total nitrogen content, and C/N ratios of suspended particulate organic matter (POM) in Zhanjiang Bay, which is a semi-enclosed bay with concentrated artificial activities in Southern China, were analyzed in order to investigate the seasonal variations in the principal POM sources in the monsoon region. In summer, the δ13C and δ15N values showed a weak correlation with the chlorophyll a (Chl a), suggesting that terrigenous sources were dominant. However, in winter, the particulate organic carbon and particulate nitrogen values were correlated with the Chl a in the middle bay and bay mouth. Moreover, the δ13C values showed a significant correlation with Chl a during the winter, indicating that the contribution of the in situ phytoplankton was relatively important and was affected by the monsoon in winter. Compared with the corresponding δ13C values, the δ15N values exhibited a complex spatial distribution. By using a Bayesian mixing model, in the upper bay, the source of POM was mainly from marine organic matter (49%) in summer, and almost an equilibrated contribution of all sources in winter. In the middle bay and bay mouth, the POM contribution mainly originated from marine organic matter (53%) during the winter. In contrast, the POM source was mainly soil organic matter (63%) in summer, suggesting that the POM was sourced from the runoff from the upstream basin. Our results suggest that the seasonal shifts of the source of POM should be taken into account when estimating C or N mass balance in the monsoon-controlled bay.

Magnetic ferroferric oxide-supported bimetallic Pd-In cluster sub-nanoparticles were used for the first time for the catalytic reduction of nitrates. Due to the unique properties of the FeOx support, the PdIn active centers could be highly dispersed in both nano- and sub-nanoscales. A variety of characterizations and the charge density difference model confirm that a strong metal-support interaction exists between the active sites and the support. The PdIn nanoparticles on FeOx show high selectivity toward nitrogen and excellent cyclic activity due to ferromagnetism, which broaden its prospect in practical water treatment. Moreover, the active centers in the sub-nanoscale are used in the nitrate reduction process for the first time and they show a distinct higher activity in denitration. The rate constant for nitrate conversion on PdIn sub-nanoparticles is larger than that for its nanometer counterpart based on the Langmuir-Hinshelwood model. High turnover frequency value and ammonia selectivity are achieved for the small-sized sub-nanocatalyst. The FeOx-supported PdIn nanoparticles and sub-nanoparticles have two application areas in water purification and ammonia recovery, respectively. Density functional theory calculations on the adsorption energies of elemental reactions are also performed, which shed some light on the catalysis mechanism and catalyst design.

The pollution of chromium wastewater is becoming more and more serious. Biological adsorption of hexavalent chromium (Cr (VI)) is an effective waste water treatment technology. In this work，non-treated leaves (NL), sulfuric acid modified leaves (SL), and hexadecyl trimethyl ammonium bromide (CTAB) modified leaves (CL) were used to remove Cr (VI) from the water. Indeed, leaves are highly effective and low-cost biosorbents, and were proven to achieve a recovery of resources from waste. In the batch experiments, the adsorption of Cr (VI) onto SL and CL was shown to be influenced by several factors, including the initial pH of the solution, the adsorbent dosage, and temperature. The X-ray Photoelectron Spectroscopy (XPS) results suggest that the reduction of Cr (VI) to the less harmful trivalent chromate Cr (III) occurred during the adsorption processes; this was followed by Cr (III) adsorption onto the surface of the adsorbents. The maximum adsorption capacities obtained for Cr (VI) at 35 °C were 170.8 and 137.9 mg/g for SL and CL at pH 2, respectively. The results show that SL and CL, as cheap and effective biosorbents of Cr (VI), realized the recycling of wastes and have good application prospects.

With the increasing concern on drilling costs in geothermal industry, more attention has been paid to the open loop geothermal system (OLGS) in a single well. For the OLGS, a vertical wellbore is generally drilled to the geothermal reservoir. Then, the injection and production intervals are perforated in the upper and lower wellbore and an insulated inner tube is installed in the wellbore. The working fluid is injected into the reservoir from the injection interval, then extracts heat from the reservoir, and finally returns to the ground surface through production interval and insulated tube. Thus, the injection and production can be accomplished in a single well, which avoids drilling an injection well and reduces drilling costs. However, few studies were conducted to investigate the heat extraction performance of OLGS comprehensively. Hence, a 3D unsteady-state multiscale model considering fluid flow and heat transfer processes of the borehole and reservoir is established. The model is verified by field data and an analytical solution respectively in various computational regions. Subsequently, the results indicate that a large flow rate is beneficial to obtain higher thermal power. The injection-production interval affects the OLGS performance significantly, and a longer interval could avoid the early breakthrough of circulating fluid effectively. And the permeability plays a remarkable role in heat production, while the influence of porosity is negligible. Furthermore, the fractures distribution near the wellbore may result in a more serious thermal breakthrough. And it is crucial to employ the insulation tube with low thermal conductivity to reduce the heat loss. The temperature field analysis depicts that the OLGS has a larger impact scope than conventional BHE, which acquires greater heat extraction performance. The main findings can offer guidance for the field application and optimal design of the OLGS.

In the present study, we report the effects of substituting casein-stabilized hydrogenated coconut oil-in-water emulsions with high-emulsifying β-conglycinin (7S) and reduced-glycinin soy protein (RG) in the preparation of oil powders. The effects of monoglycrides (MG) and protein concentration on the interfacial shear rheological behavior and the encapsulation of 7S and RG were investigated. The mean droplet size of emulsions indicated that at the same protein content, the addition of MG significantly improved the emulsifying properties of 7S (mean droplet size decreased from 332 nm to 281 nm) but had negative effects on the emulsifying properties of RG (mean droplet size increased from 741 nm to 2285 nm). The oil powders formed by 7S appeared to aggregate, which indicated that protein denaturation occurred during spray drying. However, the emulsions and oil powders formed by RG in the absence of MG exhibited small particles and a favorable dispersibility without aggregation. A competitive effect of MG on the interfacial adsorption of RG was further confirmed by the interfacial shear rheological measurements. This study suggested that RG alone is a promising substitute for caseins in the production of oil powders, and also provided a novel perspective on the design of soy protein-based encapsulation systems.

The application of the serpentine mesh layout in stretchable electronics provides a feasible method to achieve the desired stretchability by structural design instead of modifying the intrinsic mechanical properties of the applied materials. However, previous works using the serpentine layout mainly focused on the optimization of structural stretchability. In this paper, the serpentine mesh design concept is used to transform the high-performance but hard-to-stretch piezoelectric film into a stretchable form. The serpentine layout design strategies for the piezoelectric film, which aim at not only desired stretchability but also high utilization of the strain in the piezoelectric film during deformation, are discussed with experimental and computational results. A stretchable micromotion sensor with high sensitivity is realized using the piezoelectric film with a serpentine layout. Human voice recognition applications of the sensor, including speech pattern recognition with machine learning, are demonstrated with the sensor integrated with a wireless module. The stretchable micromotion sensor with a serpentine layout illustrates the broader application of serpentine layout design in the functional materials of stretchable electronics, which can further extend the range of available functional materials for novel stretchable electronic devices.

Reduced graphene oxide (rGO) supported Fe2O3 nanorod composites were prepared via a one-step hydrothermal method and further utilized for hexavalent chromium (Cr(VI)) removal from aqueous environments. The composite material exhibited an excellent removal efficiency for chromium (47.28 mg L−1), which was attributed to the electrostatic attraction and chemical reduction of chromium by the material. The removal mechanism was studied by SEM, BET, XPS, and FTIR. The results demonstrated that rGO was successfully modified by Fe2O3 nanorods (approximately 50 nm wide). Compared with graphene oxide (GO), the compound was much more easily separated from the solution after completing the removal. Furthermore, XPS characterization showed that Cr(VI) could also be reduced to low-toxicity Cr(III) by hydroxyl groups. In the variables test, it was found that the removal process was pH-dependent. The results of the designed experiments for exploring the adsorption kinetics, isotherms and thermodynamics indicated that the removal process obeyed a pseudo-second-order kinetics model, Langmuir isotherm model and that it was a spontaneous exothermal process. This study provides the possibility of hydrothermal synthesis of Fe2O3/rGO for use as an excellent material to remove Cr(VI) from aqueous environments.

An integrated calibration method of the imaging sensor and the fiber optic taper-caused distortion in an intensified Complementary Metal-Oxide-Semiconductor (CMOS) camera for the X-ray capture application is proposed. Generally, four kinds of distortions need to be corrected in this system: the column noise, the inconsistent pixel intensity response of whole frame, the nonlinear intensity response of each pixel, and the geometry distortion of whole frame. To conquer these problems, first, the column noise is estimated and subtracted from the captured image. The multiple measurement data processing method and the strip noise estimation technique are used. Second, a kind of two-step correction technique of the pixel intensity response is proposed to solve middle two distortion problems. The first step builds the ideal intensity response line for all pixels in image; and the second step estimates and compensates the correction error for each pixel by a polynomial function. Third a polynomial fitting method is also utilized to correct the geometry distortion. The RANdom SAmple Consensus (RANSC) computation mechanism is used to improve the calibration precision further. The optic indices of fiber optic taper and camera are considered to assist the selection of key parameters of these calibration method above. Many experiment results have proved the correctness and effectiveness of proposed method.

This paper discusses the 2D plane strain consolidation problem of unsaturated soil considering the time-dependent drainage boundaries. A set of time-growing exponential functions are firstly used to describe the changes of excess pore-pressures at the drainage boundaries of an unsaturated soil layer. Then, a generalized analytical solution for the 2D plane strain consolidation under these boundaries and constant initial excess pore-pressures is obtained using the finite Fourier transform and Laplace transform methods. Further, the comparisons are presented to verify the accuracy of the proposed solution. It is shown that the proposed solution is more general in the drainage boundary, and in a good agreement with the analytical solution available in the literature and the finite difference solution. Finally, a worked example is presented to investigate the consolidation characteristics under four changing drainage parameters of time-dependent drainage boundaries. The average degrees of consolidation for both air and water phases as well as that for the soil layer are presented and discussed.

The downhole coaxial heat exchanger (DCHE) is expected to exploit medium-deep geothermal resources because of its large heat transfer area. For this geothermal system, the working fluid is injected from the annulus and produced from the central insulated tubing. There have been many studies on the heat extraction performance of DCHE. However, to the best of our knowledge, most previous heat transfer models did not consider the fluid flow in the reservoir, which has a significant effect on DCHE performance. Thus, an unsteady-state heat transfer model considering heat conduction and heat convection of reservoir is presented. The finite difference method is employed to solve the mathematical model. The temperature distribution in the wellbore and nearby reservoir during the exploitation process are analyzed. Subsequently, the effects of the key factors, including flow velocity in reservoir, aquifer thickness, and thermal conductivity of cement on the heat extraction performance are studied. The simulation results depict that the temperature decreases sharply near the wellbore. The temperature impact scope in the reservoir without geothermal fluid is about 20 m, while it reaches 40 m in the aquifer. This indicates that the fluid flow in the reservoir can enhance the heat transfer of DCHE and improve the heat extraction performance. The increase of flow velocity in reservoir will increase the outlet temperature and thermal power. As the aquifer thickness increases, the outlet temperature and thermal power increase. Besides, the outlet temperature and thermal power have a remarkable decrease at the initial stage, but then remains relatively stable. The findings can offer guidance for optimal design of DCHE geothermal system.

We study the membership inference (MI) attack against classifiers, where the attacker's goal is to determine whether a data instance was used for training the classifier. Through systematic cataloging of existing MI attacks and extensive experimental evaluations of them, we find that a model's vulnerability to MI attacks is tightly related to the generalization gap -- the difference between training accuracy and test accuracy. We then propose a defense against MI attacks that aims to close the gap by intentionally reduces the training accuracy. More specifically, the training process attempts to match the training and validation accuracies, by means of a new {\em set regularizer} using the Maximum Mean Discrepancy between the softmax output empirical distributions of the training and validation sets. Our experimental results show that combining this approach with another simple defense (mix-up training) significantly improves state-of-the-art defense against MI attacks, with minimal impact on testing accuracy.

To improve the laser cleaning efficiency of Q235 carbon steel, an imaging analysis-based intelligent technique is proposed. Both offline and online computations are designed. Regarding the offline procedure, first, the corrosion images are accumulated to compute the gray-level co-occurrence matrix (GLCM) and the concave-convex region features. Second, different laser cleanings are performed to obtain various cleaned images. Third, a new cleaning performance evaluation method is developed: a metal color difference feature and a dynamic weight dispatch (DWD) corrosion texture are computed. Finally, a particle swarm optimization (PSO)-support vector machine (SVM) is utilized to forecast the laser process parameters. The corresponding laser parameters include power, linear velocity, and line spacing. For the online computation, after the GLCM and the concave-convex region features are computed, an iterative computation is used to tune the process parameters: the random laser parameters are generated constantly, and the iteration is performed and terminated only if the PSO-SVM output is positive. The experimental results have shown that the cleaning efficiency of this method can be improved, and the qualified rate is 92.5%.

Because of the labor shortage and aging of population in rural areas, and considering of the technological limitations nowadays, the tele-operational driving robot of human-in-loop is developed to help people to drive a tractor without physical attendance. The time delay control is vital for remote control of tractor steering because of the changeable weather condition and communication channel which leads to communication time delay. Firstly, the timestamp method is utilizing to measure the random time delay to transfer the problem of random time delay control to constant time delay control. Then the PID controller suitable for different time delay is study and the fuzzy controller is using to adjust the control parameters dynamically. Finally, design the experiment to evaluate the position tracking performance of the proposed algorithm which shows that the average and maximum position tracking errors are 10cm and 18cm respectively under the random time delay ranged from 0 to 1000 ms. The results indicate that the tractor steering teleoperation control with the fuzzy PID algorithm based on delay time measurement with timestamp has good tracking performance, strong robustness and important application prospects in intelligent agricultural industry.

SARS-COV-2 is a novel coronavirus discovered in Wuhan in December 30, 2019, and is a family of SARS-COV (severe acute respiratory syndrome coronavirus), that is, coronavirus family. After infection with SARS-COV-2, patients often experience fever, cough, gas prostration, dyspnea and other symptoms, which can lead to severe acute respiratory syndrome (SARS), kidney failure and even death. The SARS-COV-2 virus is particularly infectious and has led to a global infection crisis, with an explosion in the number of infections. Therefore, rapid and accurate detection of the virus plays a vital role. At present, many detection methods are limited in their wide application due to their defects such as high preparation cost, poor stability and complex operation process. Moreover, some methods need to be operated by professional medical staff, which can easily lead to infection. In order to overcome these problems, a Surface molecular imprinting technology (SM-MIT) is proposed for the first time to detect SARS-COV-2 virus. For this SM-MIT method, this review provides detailed detection principles and steps. In addition, this method not only has the advantages of low cost, high stability and good specificity, but also can detect whether it is infected at designated points. Therefore, we think SM-MIT may have great potential in the detection of SARS-COV-2 virus., Graphical abstract Image 1

Various Pickering emulsions-based system have been increasing demand for potential applications in a wide variety of fields. However, tunable emulsifiers and controllable Pickering emulsions with the ability to respond to external triggers remains an outstanding challenge. Here, we demonstrate the photo-tuning amphiphilicity in Pickering emulsions using β-cyclodextrin-grafted alginate and azobenzene derivative supramolecular self-assemblies as photoactivatable emulsifiers. Specifically, the photoisomerization of a host-guest system between β-cyclodextrin and azobenzene derivative was employed to tailor the polarity of the microenvironment, resulting in the reversible variation of hydrophilic/hydrophobic balance. The photoactivatable emulsifier based on supramolecular self-assemblies could effectively destabilize o/w emulsions by tailoring the amphiphilic balance at oil-water interface under an external UV irradiation, leading to the oil-water separation from Pickering emulsion. The light regulating demulsification is further showcased here by the photodelivery of hydrophobic model drug. Finally, this study provides a sustainable yet eco-friendly formulation for the fabrication of stimuli-responsive Pickering emulsions.

Artificial rain is explored as a remedy for climate change caused farmland drought and bushfires. Increasing the ion density in the open air is an efficient way to generate charged nuclei from atmospheric aerosols and induce precipitation or eliminate fog. Here we report on the development of a large commercial-installation-scale atmospheric ion generator based on corona plasma discharges, experimental monitoring, and numerical modeling of the parameters and range of the atmospheric ions, as well as the application of the generated ions to produce charged aerosols and induce precipitation at the scale of a large cloud chamber. The coverage area of the ions generated by the large corona discharge installation with the 7.2 km long wire electrode and applied voltage of −90 kV is studied under prevailing weather conditions including wind direction and speed. By synergizing over 300 000 localized corona discharge points, we demonstrate a substantial decrease in the decay of ions compared to a single corona discharge point in the open air, leading to large-scale (30 m ×23 m ×90 m) ion coverage. Once aerosols combine with the generated ions, charged nuclei are produced. Higher wind speed has led to larger areas covered by the plasma-generated ions. The cloud chamber experiments (relative humidity 130±10  %) suggest that charged aerosols generated by ions with a density of ∼104 cm−3 can accelerate the settlement of moisture by 38 %. These results are promising for the development of large-scale installations for the effective localized control of atmospheric phenomena.

We demonstrate the enhanced polarization modulation of electromagnetic fields through hybrid skew-ring-resonator-graphene meta-surfaces that can dynamically transform the linearly polarized waves into its cross-linearly polarized counterparts or the circularly polarized waves. Such a meta-surface consists of a grounded skew-ring resonator array inserted with a monolayer graphene sheet that controls the electromagnetic interactions between the skew-ring resonators and the ground. Especially, the reconfigurable characteristic of graphene enables the reflections to be capable of converting from the cross-linearly polarized fields to the circularly polarized waves by setting different Fermi energies with the same original co-linearly polarized incidence. Finally, we demonstrate that the bandwidth of the cross-polarization conversion would be greatly expanded when the monolayer graphene sheet is integrated with skew-bar-resonator meta-surfaces.

Nitrate (NO3&minus, ) dual isotope analysis was performed in Zhanjiang Bay, which is a closed bay with intensive human activities in South China, to investigate seasonal changes in the main NO3&minus, sources and their biogeochemical processes in the monsoon-controlled climate. The relatively low N/P ratios in Zhanjiang Bay suggests that nitrogen (N) is a limiting nutrient, which indicates that the increase of N is favorable for phytoplankton proliferation. However, a sufficient amount of ammonium was found in our study area owing to intensive human activities, which can support biological processes. Thus, less NO3&minus, biological processes were found, indicating that NO3&minus, isotopic characteristics may reveal details of the mixing from various sources. The Bayesian mixing model showed that NO3&minus, in the upper bay originated from manure (43%), soil N (30%), N fertilizer (17%), and N precipitation (10%) during winter, which reflects the local human activities, while NO3- sources during summer were mainly N fertilizer (36%), soil N (32%), and manure (31%), indicating the source as the runoff from the upper river basin. Our results suggest that nitrate dual-isotope was very useful for tracing the main NO3&minus, sources in the condition of the sufficient ammonium, and runoff exerted an important impact on the shift in NO3&minus, sources between both the local source and the source from the upper river basin during the two seasons in this monsoon-controlled bay.

A series of three-dimensional silica nanospheres with different pore sizes was synthesized in a biphasic oil-water system and their pore dimensions were adjusted by controlling the composition of the oil phase. The silica nanospheres were then wrapped with polyaniline, characterized, and the obtained silica nanosphere-polyaniline composites were used for the removal of Cr(VI). Polyaniline was generated by the polymerization of aniline. The mesoporous silica has sufficient dendritic pore channels and offers a large contact surface for the polymerization of aniline. Furthermore, the mesoporous silica nanospheres are beneficial for dispersing polyaniline and transferring aqueous Cr(VI). The silica nanosphere-polyaniline composite with the largest pore size (~15.4 nm) showed the best Cr(VI) removal performance. We also investigated the kinetic characteristics and the result could be fitted to the pseudo-second-order kinetic model. Moreover, we demonstrate that the composites maintain a high Cr(VI) removal efficiency compared to other anions (H2PO4−, SO42−, etc.), indicating their good prospect in practical wastewater treatment. Remarkably, the silica-polyaniline composites showed enhanced Cr(VI) removal efficiency under UV-irradiation. The effects of electrons and H+ on Cr(VI) reduction are also discussed based on the results of UV–vis and X-ray photoelectron spectroscopic studies and bath experiments (influence of pH on adsorption capacity). Mechanistic studies indicate that the Cr(VI) removal occurs in two stages—adsorption and reduction. The negatively charged aqueous Cr(VI) species first interact with the positively charged protonated amine groups via electrostatic attraction, and are then further reduced to less-toxic Cr(III) by the electrons and H+ donated by the amine groups on polyaniline.

Water pollution seriously endangers human health and the environment. Here we prepared and tested mesoporous LTA zeolites for the adsorption of Cu(II) from aqueous media and the captured copper was further used for electrochemical nitrate reduction. The prepared hierarchically porous LTA exhibited a high capacity (341.5 mg g−1) for Cu(II) adsorption, following the pseudo-second-order kinetic and Freundlich adsorption isotherm models well. The Cu-LTA sample was characterised by various analytical methods, and Cu(I) species were identified as the active sites for nitrate electrochemical reduction. Based on the spectral characterization and reducibility, strong metal-support interaction was found between copper and LTA, which is beneficial to the dispersion of active sites and their contacts with nitrates. In total, 10.1 g-N-NO3 g−1-Cu was reduced over the Cu-LTA-modified cathode in a three-electrode system with high N2 selectivity (92.1 %). Compared to purely microporous zeolites, mesoporous LTA has a higher capacity for Cu(II) removal and nitrate reduction. The mesoporous structure allows easy access to the inner active sites with low diffusion resistance. The low Tafel slope and high current density confirm the high activity of the mesoporous Cu-LTA, making it a promising and efficient material for the removal and reuse of heavy metal ions.

Vibration is one of the main issues taken into consideration in the design and manufacture of the pump. The radial force and vibration of the impeller induced by fluid in a centrifugal pump were investigated at different flow rates by numerical simulation. The vibrations on the volute were measured by the experiment. The variation trend of the radial displacements of the impeller is consistent with that of the radial forces, and the variation in the radial displacement lags that of the radial force. The vibration energies on the impeller and the volute were analyzed based on root-mean-square (RMS) values in the frequency domain. The distributions of energy loss in the pumps were calculated to determine the total entropy generation (TEG) and entropy generation rate (EGR). The TEG values as calculated are in close accordance with hydraulic loss. The vibration is a result of the poor flow patterns and consequently results in increased energy losses in the pump.

Sensor metadata tagging, akin to the named entity recognition task, provides key contextual information (e.g., measurement type and location) about sensors for running smart building applications. Unfortunately, sensor metadata in different buildings often follows distinct naming conventions. Therefore, learning a tagger currently requires extensive annotations on a per building basis. In this work, we propose a novel framework, SeNsER, which learns a sensor metadata tagger for a new building based on its raw metadata and some existing fully annotated building. It leverages the commonality between different buildings: At the character level, it employs bidirectional neural language models to capture the shared underlying patterns between two buildings and thus regularizes the feature learning process; At the word level, it leverages as features the k-mers existing in the fully annotated building. During inference, we further incorporate the information obtained from sources such as Wikipedia as prior knowledge. As a result, SeNsER shows promising results in extensive experiments on multiple real-world buildings.

A convenient and simple hydrothermal method was used to prepare a graphene oxide nanosheet-modified Ti nanocomposite (Ti-GO) electrode with highly stable nitrate reduction activity. The samples’ electrochemical activity for nitrate reduction was studied under 120 min electrolysis. The results demonstrated that Ti-GO showed higher nitrate reduction efficiency than Ti and Cu electrodes, and comparable to Cu-Zn electrode due to its surface GO modification. The low current efficiency of the electrode (0.0015) was attributed to its high selectivity of ammonia. The specific addition of NaCl resulted in efficient by-products removal and increased reduction efficiency. Electrochemical test showed that the Ti-GO electrode has stronger electrochemical activity and much higher real surface area than that of Ti electrode. The Ti-GO electrode exhibited excellent durability without apparent variation in the electrolytic property was observed after 5 treatment cycles (10 h in total), while only slight decrease in the reduction efficiency was noted (Standard Deviation = 1.72). In conclusion, the developed Ti-GO electrode showed excellent electroreduction behavior and promising results for electrochemical nitrate reduction.

Recent experiments have reported that nanotwinned and nanopolycrystalline diamond-like materials exhibit unprecedented hardness, enhanced fracture toughness, and improved thermal stability. This extraordinary finding has raised fundamental issues on atomistic hardening mechanisms governing the combined resistance to indentation of the chemical bonds in these nanostructured hardest covalent solids. Indentation-induced transition from diamond, nanopolycrystalline diamond and nanotwinned diamond into graphite at the area of indentation has been experimentally confirmed. Here, using molecular dynamics simulation, we unveil a new graphitization resistance dominated hardening mechanism that hinders graphitization by introducing a large number of twin boundaries (TBs) and grain boundaries (GBs) commonly known in nanostructured diamond, leading to greatly enhanced hardness of an indented diamond lattice. This remarkable nanostructure-generated additional graphitization resistance mechanism offers fundamental insights for understanding and improving the stress response of nanotwinned and nanopolycrystalline diamond under indentation and is verified by comparing the results with those from the experiment.

O/W Pickering emulsions formed with silica nanoparticles adsorbed with amphiphilic alginate derivatives produced a longer stability. Ugi-Alg was obtained by a mild and efficient Ugi four-component ...

In this study, cholesteryl-grafted sodium alginate derivatives (CSAD) with different molecular weights were synthesized by esterification. The structure of CSAD was confirmed by FT-IR and 1H NMR spectrometers. The effects of pH and CSAD polymer concentration on the self-assembled behavior and particle size of CSAD were investigated by fluorescence measurement (FM) and dynamic light scattering (DLS). In the presence of Ca2+, the cholesteryl-grafted sodium alginate derivative was used for fabricating self-assembled nanoparticles that can effectively encapsulate the drug acetamiprid. The drug-loaded nanoparticles were characterized by transmission electron microscopy (TEM). The encapsulation efficiency (EE) and acetamiprid drug release behavior from the nanoparticles were also studied. The results reveal that CSAD self-assembled nanoparticles had a diameter of 100nm and were nonaggregated in aqueous media; Moreover, the encapsulation efficiency and the release behavior of nanoparticles were influenced by the MW of CSAD. The mechanism of acetamiprid release was found to vary from non-Fickian (anomalous) to Fickian transport with a decrease in the molecular weight of CSAD.

Although bacterial cellulose (BC) and bacterial cellulose nanocrystals (BCNs) have considered to be edible, non-toxic, biocompatible and biodegradable, there is still the dearth of reports of BC and BCNs as the emulsifiers of Pickering emulsions with respect to the applications in foods, cosmetics and medicines. In this work, BC with ultrafine network architecture and 8–40 nm crystalline microfibrils in diameter was produced by Acetobacter xylinum , and then it was hydrolyzed by sulfuric acid followed by the oxidation of hydrogen peroxide to prepare BCNs. The physicochemical properties of BC and BCNs were contrastively evaluated by FT-IR, XRD, TGA and dynamic light scattering (DLS). The emulsifying performances of BC and BCNs in the stabilization of olive oil Pickering emulsion were further evaluated by optical microscope (OM) and fluorescent microscope (FM). Experimental results showed that the sulfuric acid hydrolysis of BC induced the removal of the amorphous components and the cleavage of the crystalline microfibrils, making BCNs possess the initiating decomposition temperature of 350 °C, the crystallinity index (CrI) of 89.6%, average size of 259.6 nm with PDI of 0.26 and zeta potential at about −34.8 mV, which exhibited high thermal stability and good emulsifying performance in comparison with BC. Furthermore, the effects of pH and ionic strength on emulsion stability were also investigated. In comparison to BC, BCNs were more sensitive in response to the change of pH and ionic strength.

The performance of resistive switching (RS) device based on sandwich structure is greatly affected by the characteristics of the RS layer, electrode, and interface. In this work, the effect of rapid thermal annealing (RTA) (300 °C for 120 s) on the RS performance of Ta/TaOx/Ru device was investigated. The discrete distribution in high resistance state (HRS) and low resistance state (LRS) was suppressed after RTA. Meanwhile, the endurance in oxygen RTA is higher 104 times than that of vacuum RTA. The optimized oxygen RTA is contributed to change the microstructure of TaOx (amorphous to nanocrystal), providing the local conductive path, and implant oxygens in top electrode (TE) Ta, acting as an oxygen source (reservoir). It is shown that the nanocrystal TaOx and the oxygen content in TE are intrinsically crucial to the RS behavior and the simple low temperature oxygen RTA is a powerful technique to optimize the RS performance.

Soft emulsifiers with relatively suitable structural controllability are necessarily required for the preparation of multifunctional Pickering emulsions. Herein, a β-cyclodextrin-grafted alginate/azobenzene-functionalized dodecyl (Alg-β-CD/AzoC. 12) polymeric supra-amphiphile was designed based on the host-guest interfacial self-assembly. As compared with Alg-β-CD amphiphilic polymers, the interfacial tension of Alg-β-CD/AzoC12 supra-amphiphilic assemblies reduced from 29.57 mN/m to 0.18 mN/m, indicating the great amphiphilicity derived from Alg-β-CD/AzoC12 supra-amphiphilic assemblies. With the increase of pH, the interfacial microstructures transformed from flocculated structures, spherical structures into deformed structures. Especially, the spherical microstructures with the highest interfacial viscoelasticity and thickness demonstrated the highest emulsifying efficiency due to the steric hindrance mechanism. Moreover, the interfacial elastic modulus of adsorbed layers exhibited ~4 times of that upon the ultraviolet illumination. These results disclosed that the interfacial microstructures could be readily regulated by the tunable amphiphilicity of Alg-β-CD/AzoC12 assemblies, which would be useful for the applications of Pickering emulsions in numerous fields.

Polyurethane (PU) sponge has a wide range of applications in our daily life. Unfortunately, the PU sponge is highly flammable and becomes a breeding ground for bacteria, thereby threatening human health and life. To date, it remains a challenge to improve the flame retardant and antibacterial properties of PU sponge simultaneously without destroying its inherent elasticity and flexibility. Here we report a novel composite coating on the PU sponge using bioderived phytic acid and sodium lignosulfonate via a facile soaking method. Compared to the pristine sponge, the coated PU sponge can reach a 32% reduction in peak heat release rate during cone calorimeter test, and prevent melt dripping after being ignited by a butane torch and the flame can be self-extinguished after the torch is removed. The resultant composite coating also demonstrates a killing rate of 99% against Staphylococcus aureus. Meanwhile, the coated PU sponge can retain the inherent elasticity and flexibility even after 500 cycles of compression. Furthermore, the coating materials are easily recyclable, which provide a useful reference for multifunctional treatment of sponge and cyclic utilization of resources.

It is very urgent to build memristive synapses and even wearable devices to simulate the basic functions of biological synapses. The linear conductance modulation is the basis of analog memristor for neuromorphic computing. By optimizing the interface engineering wherein Ta/TiO x /TaO x /Ru was fabricated, all the memristor devices with different TiO x thickness showed electroforming-free property. The short-term and long-term plasticity in both potentiation and depression behaviors can be mimicked when TiO x was fixed at 25 nm. The presented memristive synapses simulated the stable paired-pulse facilitation and spike-timing dependent plasticity performance. The potentiation and depression in linearity and symmetry improved with the TiO x thickness increasing, which provides the feasibility for the application of artificial neural network. In addition, the device deposited on polyimide (PI) still exhibits the synaptic performance until the bending radii reaches 6 mm. By carefully tuning the interface engineering, this study can provide general revelation for continuous improvement of the memristive performance in neuromorphic applications.

In this study, VO2 was deposited on glass through low pressure annealed metal vanadium thin film. The crystal structure, surface morphology and optical transmittance property of the film were characterized by X-ray diffraction, scanning electron microscopy and UV/VIS/NIR spectrophotometer, respectively. When the film thickness is higher than 88 nm, XRD showed that the deposited films appears only at 27.92° indexed to VO2 (011). The calculated grain sizes of VO2 increased from 33.6 nm to 39.2 nm with the increasing of film thickness. The thermal hysteresis showed that the phase transition temperature is in a range of 53–58 °C, which is much lower than that of single crystal VO2 (68 °C). In addition, the films exhibit the optimal thermochromic performance with the luminous transmittance of 48.2% and the solar modulation of 6.7%. This method revealed the facile fabrication of large scale high performance VO2 on glass for thermochromic based devices.

Supported noble metal catalysts are extensively used for propane dehydrogenation in both the academy and industry. When the active components are fixed, the variation and improvement of the support will significantly affect the performance of the catalyst. Here we first prepared a series of PtSn/TS-1 catalysts with systematically controllable sizes of TS-1 zeolite supports. The particle sizes of the as-prepared TS-1 zeolite supports are from 100 nm to 5.72 μm. The TS-1 supports exhibited only weak acid sites, which avoids some side-reactions such as cracking and coking. The minimal size TS-1 (∼100 nm)-supported PtSn catalyst gave the best catalytic performance and almost preserved the activity after a four-cycle reaction. The improved activity is ascribed to the hierarchically porous structure of the small-sized TS-1 sample, whereby diffusion hinders the mass transportation no more as certified by the Weisz–Prater criterion. The relationship between propane conversion and support size was fitted by a quadratic function. To further investigate the deactivation process, the species of deposited carbon was analyzed by in situ Raman methods. The work gave a new strategy for improving the catalytic performance of conventional supported catalysts in the PDH reaction, as well as some other heterogeneous catalysis.

Four different surface fractal dimensions (Dsf’s) of anisotropic silica (SiO2-x) similar in size were synthesized by layer-by-layer molecular imprinting strategy. Grafting was confirmed by FT-IR and X-ray photoelectron spectroscopy. The surface and interfacial properties of particles were confirmed by transmission electron microscopy, nitrogen adsorption, dynamic light scattering, and contact-angle measurement. Results showed that Dsf ’s of SiO2-1, SiO2-2, SiO2-4, and SiO2-6, were 2.47, 2.55, 2.62, and 2.56, respectively. Moreover, the modified silica shape varied from spherical to anisotropic particle, and particle hydrophobicity decreased with increased the Dsf. Stable emulsions were prepared by these particles. The effects of particle concentration, hydrophobicity, and Dsf on the formation, stability, and rheology of emulsions were investigated using an optical microscopy and rheometer. Optical microscopy images showed that unmodified silica failed to form stabilized emulsions due to excellent hydrophility, and particles with Dsf = 2.62 and 0.2 wt% concentration were the best for stabilized emulsions. Moreover, increased Dsf led to decreased droplets size smaller and easier network formation. Rheology measurement further showed that increased Dsf led to increased viscoelasticity and thermal stability of emulsions due to the formation of rigid volume-filling networks. This finding indicated that the particle fractal structure strongly affected the structures in the suspension to immobilize the emulsion droplets in these networks. Emulsion also exhibited longer λ-cyhalothrin release speed with increasing Dsf using λ-cyhalothrin as model hydrophobic drug. The λ-cyhalothrin release kinetics well-fitted the Weibull model.

Using the gradient phase discontinuities that meta-mirrors provide, we show that the incident wave can be reflected anomalously with a broad angle range of negative reflections. Such reversed behaviors promote the immediate applications for the planar meta-mirrors to steer the signals more arbitrarily and the convex meta-mirrors to focus and collimate electromagnetic fields. We practically implement these negative reflecting meta-mirrors through an arrangement of subwavelength ring patches and generate the desired phase distribution by also considering the incident angle. Finally, the experiments are carried out to verify the functionality of the convex meta-mirror firstly, and the performances of the planar meta-mirror are also tested by further building up a dual reflector system with the demonstration of obtaining the plane wave from the convex meta-mirror and then having the well collimated beam negative reflected by the planar meta-mirror. The proposed design should be readily applicable to a wide range of electromagnetic problems, especially for devising smart planar illusion devices, and highly directive antennas mounting on convex surfaces of various platforms.

Sono-photo-Fenton, sono-Fenton and photo-Fenton methods combined with heterogeneous TiO 2 nanoparticles are adopted to investigate the degradation of sodium alginate (NaAlg), and the kinetics mechanism is also explored. Experimental results suggest that the reaction order of NaAlg degradation ( n ) is 0.51 and the extent of photocatalytic degradation can increase with the loading of TiO 2 nanoparticles. Meanwhile, as the catalyst concentration increases from 0.05 to 0.5 gL −1 , the degradation rate constant ( k ) is decreased. In addition, the structure of degraded NaAlg is characterized by Fourier transform infrared (FT-IR), 1 H NMR spectroscopy, and X-ray diffraction analyses. The FT-IR and 1 H NMR spectra results indicate that the C2-C3 bond in the structure of NaAlg is broken and intra-molecular esters are formed during the degradation process due to the strong oxidization of the Fenton system. In general, the sono-photo-Fenton process with TiO 2 nanoparticles could provide an efficient way to degrade the NaAlg to low-molecular-weight.

A fiber-optic interferometer is proposed and demonstrated experimentally for ultrasonic detection. The sensor consists of a compact Michelson interferometer (MI), which is fixed in a tilted-tube end-face (45°). Thin gold films are used for the reflective coatings of two arms and one of the interference arms is etched serving as the sensing arm. The spectral sideband filter technique is used to interrogate the continuous and pulse ultrasonic signals (with frequency of 300 KHz). Furthermore, because of the asymmetrical structure of the sensor, it presents strong direction-dependent ultrasonic sensitivity, such that the sensor can be considered a vector detector. The experimental results show that the sensor is highly sensitive to ultrasonic signals, and thus it can be a candidate for ultrasonic imaging of seismic physical models.

Membrane fouling is a serious concern in municipal wastewater treatment using nanofiltration (NF). The variation of NF membrane fouling at different operational durations were monitored and evaluated to understand the evolution of fouling mechanism in the present study. Six representative cleaning methods were picked for tests to deconstruct the structure and composition of the fouling layers on membrane surface. Characteristics of membrane surface morphology and foulants were analysed using advanced methods to investigate the evolution of membrane fouling. Both the composition and concentration of foulants on membrane surface showed significant variations with time during the whole operational duration, indicating the necessity of clear and precise understanding for the evolution of membrane fouling to expound its mechanism in depth. The fouling layers were mainly composed of hydrophobic organics while most inorganic salts were deposited on the surface or embedded into the upper layer of the cake in a short duration. However, after a long duration, the cake layer became thinner with much higher proportion of hydrophilic organics. Meanwhile, more inorganic foulants penetrated deep into the cake layer or even directly absorbed on the membrane surface, which resulted in more complicated fouling scenarios. Moreover, more efficient and effective targeted cleaning strategies could be further established based on the fouling mechanism identified.

Side-by-side operations are often used in the offshore industry for offloading of oil and gas. Loads on the mooring lines, vessel motions and wave elevations in the gap are among the most critical issues for this type of operations, and they are highly dependent on the hydrodynamic interaction between the vessels. On the other hand, there is limited experimental data available to validate numerical predictions of these hydrodynamic effects. This paper presents extensive experimental benchmark data, and a detailed uncertainty analysis of the results of two-body interaction model tests carried out in the towing tank of Memorial University, Canada. Sources of uncertainty were identified and quantified for 6-DOF motions, wave elevations in the gap between the two models, and drift forces. A combined experimental and numerical method was developed to quantify the uncertainties in model geometry, model mass properties, locations of models, and the set-up of the mooring system. Experimental results with associated uncertainties are compared with potential-flow solutions in the frequency domain. It was found that uncertainties due to the model geometry are negligible, however, those due to the model mass properties may be significant for roll motions. The uncertainty in gap leads to large uncertainties in all the measured results.

Existing methods in the Visual Storytelling field often suffer from the problem of generating general descriptions, while the image contains a lot of meaningful contents remaining unnoticed. The failure of informative story generation can be concluded to the model's incompetence of capturing enough meaningful concepts. The categories of these concepts include entities, attributes, actions, and events, which are in some cases crucial to grounded storytelling. To solve this problem, we propose a method to mine the cross-modal rules to help the model infer these informative concepts given certain visual input. We first build the multimodal transactions by concatenating the CNN activations and the word indices. Then we use the association rule mining algorithm to mine the cross-modal rules, which will be used for the concept inference. With the help of the cross-modal rules, the generated stories are more grounded and informative. Besides, our proposed method holds the advantages of interpretation, expandability, and transferability, indicating potential for wider application. Finally, we leverage these concepts in our encoder-decoder framework with the attention mechanism. We conduct several experiments on the VIsual StoryTelling~(VIST) dataset, the results of which demonstrate the effectiveness of our approach in terms of both automatic metrics and human evaluation. Additional experiments are also conducted showing that our mined cross-modal rules as additional knowledge helps the model gain better performance when trained on a small dataset., Comment: 9 pages, to appear in ACM Multimedia 2019

Paclitaxel is broad-spectrum anticancer drug which has been widely used in clinic. However, traditional drug delivery often suffers from the scarcity of resources and systemic toxic side effects caused by the localization to non-tumor areas, rendering cancer treatment extremely challenging. To address this problem, we developed a novel multifunctional drug delivery system of a poly(lactic-co-glycolic acid) (PLGA) drug-loaded magnetic Janus particles (DMJPs) using electrohydrodynamic (EDH) co-jetting. The DMJPs were loaded with three compartments each with distinct function, i.e. paclitaxel for killing cancer cell, Fe3O4 nanoparticles for target location, and rhodamine B for fluorescence tracing, respectively. The Janus structure of the DMJPs, as demonstrated by the loaded nano-quantum dots CdS/ZnS and CdSe/ZnS in different compartments, enhanced not only the drug loading and encapsulation efficiency but also the cumulative release rate of the loaded drugs from DMJPs in different media. More importantly, DMJPs exhibited specific and high toxicity only to human breast cancer cells (MDA-MB-231), but not to mouse embryonic fibroblasts (NIH-3 T3). Consistently, DMJPs induced the higher lethal effect on cancer cells than paclitaxel suspension of high concentrations. Under guidance of external magnetic field, DMJPs can readily target and accumulate on and inside cancer cells for cell elimination. The specific targetability, selectivity, and toxicity of DMJPs on cancer cells would greatly avoid any potential side effects and reduce the overdose of drugs for conventional drug delivery. This work hopefully provides a new drug delivery system for the development of anticancer drug systems for clinical and precision medicine treatment.

Cyclin-dependent kinases play significant roles in cell cycle progression and are promising targets for cancer therapy. However, most potent CDK inhibitors lack the balance between efficacy and safety because of poor selectivity. Given the roles of CDK2 in tumorigenesis, selective CDK2 inhibition may provide therapeutic benefits against certain cancer. In this study, a series of 4-benzoylamino-1H-pyrazole-3-carboxamide derivatives were designed, synthesized, and evaluated. The most selective compound DC-K2in212 in this series exhibited high potency towards CDK2 and had effective anti-proliferative activity against A2058 melanoma cell line and MV4-11 leukemia cell line while exhibiting low toxic effect on human normal cell lines MRC5 and LX2. The molecular modeling illustrated that compound DC-K2in212 had the similar binding mode with CDK2 as C-73, the most selective CDK2 inhibitor reported so far, which might account for selectivity against CDK2 over CDK1. Further biological studies revealed that compound DC-K2in212 suppressed CDK2-associated downstream signaling pathway, blocked cell cycle progression, and induced cellular apoptosis. Therefore, compound DC-K2in212 could serve as a potential CDK2 inhibitor for further development.

Most structural self-healing materials were developed based on either reversible supramolecular interaction or dynamic covalent bonding. It seems a good idea to incorporate self-healing properties into high-performance materials. In this study, we fabricated the alginate-based cyclodextrin and polyacrylamide azobenzene highly stretchable and tough interpenetrating composite hydrogel with self-repairing behavior under light irradiation. Initially, the alginate-based cyclodextrin and polyacrylamide azobenzene were designed and synthesized. The corresponding structural, thermal, and morphological properties of hydrogels were characterized. The reversible transformation of the sol-gel can be achieved by the irradiation upon ultraviolet light and visible light. The self-healing behavior of this composited gel is based on the host-guest interaction between cyclodextrin and azobenzene. The recovery gel elongation at 48 h healing in the dark condition was is 0.04 MPa, with an elongation of 1140 %. Therefore, this gel can achieve self-healing ability while maintaining highly stretchable and tough performance.

Based on the Ta/TaOx/ITO structure, self-current compliance behavior in the resistive switching (RS) properties was investigated. The formation and rupture of metallic indium (In) conducting filaments (CFs), which contributes to the RS in this device, are confirmed by the variable temperature electrical test combined with X-ray photoelectron spectroscopy (XPS) analysis. It showed high uniformity and endurance performance up to 108 switching cycles, including a lower power consumption. The excellent electrical performance can be attributed to the role of a series resistor of ITO because the adverse effects of the voltage (or current) overshooting can be efficiently suppressed, resulting in the controllability of the In CF formation and rupture. The XPS depth profile results confirmed the oxygen exchange at the TaOx/ITO interface, combined with the Ohmic conduction mechanism at low resistance state, indicating that the ITO interface acts as the series resistor rather than the Schottky barrier.