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Glutathione and 2-aminopyridine are used as carbon sources to prepare carbon dots (CDs) by a one-step hydrothermal reaction. The results show that the average particle diameter of CDs is 8.64 nm with uniform size distribution and the fluorescence quantum yield is 13.62%. We further demonstrate that novel CDs possess highly selective sensing of Fe3+ from 0.2 to 200 μM with a low detection limit (0.194 μM). Meanwhile, the fluorescence of CDs can be repeated many times by the addition of S2−. Moreover, the CDs are used for biological imaging of living cells with well cell penetrability and low toxicity. Furthermore, it is successfully applied for anti-counterfeiting and information encryption. More interestingly, it can be doped with hydrogel and filter paper to prepare solid-phase sensors exhibiting high sensitivity and fast response, demonstrating their tremendous potential for the simple, rapid, and low-cost monitoring of Fe3+ and S2−.

Aerogel materials have wide research and application in the fields of thermal insulation and functional materials. Although graphene sheet has high strength in conventional graphene aerogels, the interaction between sheets is weak. The overall strength of graphene aerogels is not high enough. Aerogels, especially halloysite aerogels, have been successfully synthesised in recent years, but their electrical potential expansion is slightly insufficient. Therefore, in view of the enhancement of the mechanical properties of aerogels and the development of electrical potential, the idea of organic–inorganic hybrid (OIH) aerogel was proposed. Graphene halloysite OIH aerogel materials were prepared by graphene sheets and halloysite fibres. The preparation and microstructure of materials were characterised using Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy and nitrogen adsorption–desorption. Meanwhile, the mechanical properties of aerogels were also studied, and the stress transfer behaviour of aerogels was investigated by Raman spectroscopy. The results showed that the OIH aerogel was successfully obtained. The strength of the OIH aerogels was much higher than that of the mixture of graphene and halloysite aerogel. The OIH network aerogels had more effective stress transfer effect depending on the chemical bonds between the networks.

Fluorescent carbon dots (CDs) have attracted considerable interest due to their superior optical properties and facile preparation. In this work, O-phenylenediamine and melamine were used as precursors for the one-step hydrothermal synthesis of novel orange emissive CDs (O-CDs) in an aqueous solution. The fluorescence intensity (580 nm) of the O-CDs exhibited a good linear relationship with Ag

In this paper, wavelet packet transform (WPT) and common space pattern (CSP) algorithm are used to extract signal features. Firstly, the wavelet packet transform is used to decompose the signal, and the appropriate wavelet packet subband is selected for reconstruction. Then, feature vectors are extracted by common space pattern projection mapping. Finally, it innovatively combines linear discriminant classifier (LDA) to classify. The results on BCI-Competition-IV-2b data set show that the average classification accuracy is 86.29%.

Glutathione and 2-aminopyridine are used as carbon sources to prepare carbon dots (CDs) by a one-step hydrothermal reaction. The results show that the average particle diameter of CDs is 8.64 nm with uniform size distribution and the fluorescence quantum yield is 13.62%. We further demonstrate that novel CDs possess highly selective sensing of Fe

Specifically, visually, and quantitatively monitor copper ion (Cu

SAR and visible image matching provides many applications in remote sensing, image fusion and image guidance with laborious problems with regard to the potential nonlinear intensity differences between two images. This paper proposes an image matching approach which use the phase congruency (PC) to detect corners and log-gabor filters for obtaining feature descriptor in the SAR and visible images. PC can provide inherent and rich image textures for the images with intricate grayscale changes or noise, which is utilitized to detect the corners. The moments of PCs for the images are calculated to obtain the keypoints and the log-gabor filters are employed to acquire the feature descriptors. Five evaluation methods are used for testing the results of the algorithm for three pairs of images and its result is compared to the SIFT algorithm. The experiment performance show that the advocated algorithm is better than the SIFT algorithm.

Earthquake is a kind of natural disaster, which will have a great impact on the building structure. In the vibration control field of building structures, the timeliness of system stability is extremely important. In traditional control methods, the timeliness is not paid enough attention for systems with uncertain seismic waves. For setting this problem, fuzzy adaptive compensation control for uncertain building structural systems by sliding-mode technology is proposed. It is combined with fuzzy adaptive control and sliding-mode control to ensure that the system can be stable with satisfied timeliness. Also, saturation function is used to ensure the feasible physical implementation of the control system. Compared with the traditional LQR (linear quadratic regulator) control, the simulation results showed that the proposed method can make the system reach a stable state with rapid convergence performance and has a feasible physical implementation.

Fluorescent carbon dots (CDs) have attracted considerable interest due to their superior optical properties and facile preparation. In this work, O-phenylenediamine and melamine were used as precursors for the one-step hydrothermal synthesis of novel orange emissive CDs (O-CDs) in an aqueous solution. The fluorescence intensity (580 nm) of the O-CDs exhibited a good linear relationship with Ag+ in the range of 0.0–50.0 μM with the detection limit of 0.289 μM. Moreover, the O-CDs were successfully used to determine Ag+ in biological samples (Hela cells) because of their low cytotoxicity, and good biocompatibility. Besides, the O-CDs-doped solid-phase detection materials (test paper and hydrogel) were employed to monitor Ag+ qualitatively and quantitatively, indicated that the O-CDs had a great capacity for the detection of Ag+ in biological and environmental areas. Based on their extraordinary fluorescence property, the O-CDs could also be used as security ink. Overall, based on their excellent fluorescent performance, the CDs in this study have significant potential for practical application toward solid-phase sensing and security ink.

Specifically, visually, and quantitatively monitor copper ion (Cu2+) is critical in the area of biological and environmental detection. Herein, a ratiometric fluorescent probe with benzoxazole appended xanthenes skeleton was constructed and further employed to monitor Cu2+ in Hela cells, real water samples, and test strips. An easily distinguishable colorimetric (colorless to red) and fluorescence (green to red) change could be observed by naked eye under the portable UV lamp (365 nm) and the changes could be recovered by adding S2−. Furthermore, electrospinning technique was employed to fabricate a probe composited fluorescent sensing film (PMMA) for realizing the visual and recyclable monitoring of Cu2+, indicating that the probe-composited fluorescent sensing film has great potential for on-site and naked-eye detection of Cu2+ in practical.

A simple naphthofluorescein-based probe was designed and synthesized by a two-step method. As expected, there was a good linear relationship between fluorescence intensity (680 nm)/absorbance (640 nm) and H2S concentration in the range of 2.00–10.0 μM with a detection limit of 0.50 μM/0.10 μM (S/N = 3). This probe was applied to monitor H2S concentration in red wine samples. Furthermore, it was successfully used to image exogenous H2S in living Hela cells, indicating its potential application in biology and medicine.

Background We intended to examine the functional role of microRNA 26 (miR-26a) in regulating H2O2-induced cytotoxicity and apoptosis in RGC-5 cells in vitro. Method Various concentrations of H2O2 (0–1000 μM) were added in RGC-5 culture. Cell cytotoxicity was monitored by viability assay and gene expression level of miR-26a examined by qRT-PCR. MicroRNA-26a mimic was then applied in the RGC-5 culture to examine its effect on upregulating endogenous miR-26a and rescuing H2O2-induced cytotoxicity. TUNEL immunostaining assay was used to further assess the protective effect of upregulating miR-26a on H2O2-induced apoptosis in RGC-5 cells. Direct targeting of miR-26a on Phosphatase and tensin homolog (PTEN) signaling pathway was assessed by luciferase assay and western blotting. PTEN was then ectopically over-expressed in RGC-5. And its effects on miR-26a mediated apoptosis protection in RGC-5 were investigated by western blot and TUNEL assay. Results H2O2 induced cytotoxicity and down-regulated miR-26a in dose-dependent manner in RGC-5 cells. MiR-26a-mimic upregulated endogenous miR-26a gene levels, and then reduced H2O2-induced cytotoxicity, as well as H2O2-induced apoptosis in RGC-5 cells. PTEN was directly targeted by miR-26a. PTEN protein was upregulated, and phosphorylated AKT protein down-regulated while miR-26a was upregulated to reduce H2O2-induced apoptosis. Finally, overexpressing PTEN reversed the protective effect of miR-26a upregulation on RGC-5 apoptosis. Conclusion Upregulating miR-26a protects RGC-5 cell against cytotoxicity and apoptosis, probably through down-regulation of PTEN.

In order to evaluate space nature quadric surface error accurately in any position and orientation with the requirement of the minimal zone, a method based on geometric and position parameters optimized by Particle Swarm Optimization (PSO) is proposed. Three accurate evaluating models of the method are established according to the definition of conicoid profile error. The geometric and position parameters between measured profile and theoretical profile are matched through fitting the general quadric surface equation based on improved particle swarm optimization (IPSO) which adopted the maximum in all of distances between measured points and quadric surface as fitness. A standard cone was evaluated by the above method in experiment, and compared with Spatial Analyzer (SA) and Least Square Method (LSM). Experimental results indicate the profile error of cone is 0.1168mm more accurate than that of other methods. The results show that method is more effectively used in space nature quadric surface error evaluation.

A direct radius compensation and evaluation method for quadric surface at arbitrary position in space with coordinate measuring machining (CMM) is proposed. The radius error is compensated by the optimization model directly based on minimum condition principle with the object function value calculated by angle subdivision approach algorithm. The model is optimized by Improved Particle Swarm Optimization (IPSO) algorithm. Particle Swarm Optimization (PSO) improved by the idea of optimized analytical method, natural selection and crossover with the maximum distance as the object function based on minimum condition principle is proposed. In the experiment, the direct method and the usual method based on B-spline are employed to evaluate the quadric profile error and compare. The direct method result is 0.1811mm, more accurate than the usual method result 0.2522mm. Experimental evidence shows that the direct method is robust and efficient.

In nonlinear predictive functional control, the speed of time varying response is slow. This problem is considered in this paper. A strategy, based on least squares support vector machine (LS-SVM) of nonlinear predictive functional control of recursive subspace model, is developed. The predictive model of the nonlinear predictive functional control is Hammerstein model. Gets output function of nonlinear static link according to principle of LS-SVM, and identifies linear dynamic link with model of recursive subspace. On the basis of distinguishing effectively to the nonlinear objects, realizes rapidly distinguish, improves time varying response speed, and has good performance of tracking ability in nonlinear predictive functional control. Simulation results show the validity and superiority of this algorithm.

As the error in the process of automatically mixing by weighing control is consisted in the glue mixing and dosing precise system Micro-D based on load cells in parallel, and the system has the characteristic of batching weight loading for each chemical components flow, so this paper makes an particular analysis with static error, dynamic error and dynamic delay error, puts forward several methods such as subtracting weight for eliminating error, subtracting affixed weight, and beforehand closure electro-valves using predictive control based error compensation, so that the average error which is measured by the error measurement system is less than 0.008 kg, the standard deviation is less than 0.006. Experimental results show that the design of glue mixing & dosing precise system Micro-D can accord with the requirement of precise measurement for glue mixed.

These instructions give you basic guidelines for preparing papers for conference proceedings. This paper put forward a kind of new method aimed at identification of Hammerstein models in nonlinear system. With the analysis of the problem of sparseness that based on least square support vector machine (LS-SVM), the predictive output function of static nonlinear loop was obtained, and applied state space model to dynamic linear loop, got a new nonlinear identification model of Hammerstein. Simulation results shows that the method has better precision of identification, high-speed of response. Its computing time approximately for other modelspsila 30%, improved identification efficiency obviously, and testified the validity and feasibility of the method.