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Silica nanoparticles are used as additives to organic coatings to modify their properties. The interface of inorganic nanoparticles with an organic matrix can be a preferred location for accumulation of water. Surface treatment of nanoparticles with 3-glycidoxypropyltrimethylsilane (silane) is one way to reduce the water accumulation. In this work, using atomistic simulations (MD), we studied the effects of silane treatment on accumulation of water at the interface of nanoparticles. Three different epoxy phases and two methods of deposition of water were simulated. Water molecules were studied at two locations: (i) the interface of nanoparticles, and (ii) in the matrix of coatings. Additionally, the changes in the organic matrix due to surface treatment of nanoparticles were studied. The simulations show how silane treatment affects the interactions of water with nanoparticles in different epoxies, and also how silane treatment reduces the water accumulation in an organic matrix with nanoparticles.

It is known that microorganisms degrade many materials. However, very little is known about the biodegradation of marine coatings. In this study, we explored the degradation of epoxy resin varnish coating in sterile seawater and seawater inoculated with Pseudomonas putida by the coating permeability analysis, electrochemical impedance spectroscopy, contact angle test, scanning electron microscopy, Fourier transform infrared spectroscopy. The decrease in the corrosion resistance of the coating was significantly higher in seawater inoculated with Pseudomonas putida than in sterile seawater between 48 h and 25 days of coating immersion. The extensive under-coating corrosion appeared on the substrates in both seawater systems, but the corrosion in seawater inoculated with Pseudomonas putida was much more serious. These results suggested that Pseudomonas putida significantly decreased the corrosion resistance of the coating and might decompose the coating. Some pulverization and tiny holes were found on the coating in seawater inoculated with Pseudomonas putida. Moreover, the absorbance of the C OH peak for the unimmersed coating and the coating immersed in sterile seawater was significantly higher than that for the coating immersed in seawater inoculated with Pseudomonas putida. The results proved that Pseudomonas putida degraded the coating. The degradation could involve the hydroxyl oxidation.

The ionization processes of NH3 molecule are studied by photoelectron velocity map imaging technique in a linearly polarized 400-nm femtosecond laser field. The two-dimensional photoelectron images from ammonia molecules under different laser intensities are obtained. In the slow electron region, the values of kinetic energy of photoelectrons corresponding to peaks 1, 2, 3, and 4 are 0.27, 0.86, 1.16, and 1.6 eV, respectively. With both the kinetic energy and angular distribution of photoelectrons from NH3 molecules, we can confirm that the two-photon excited intermediate Rydberg state is A∼1 A 2 ′ ′ ( v 2 ′ = 3 ) state for photoelectron peaks 2, 3, 4, and the three peaks are marked as 1223 (2 + 2), 1123 (2 + 2), and 1023 (2 + 2) multi-photon processes, respectively. Then, peak 1 is found by adding a hexapole between the source chamber and the detection chamber to realize the rotational state selection and beam focusing. Peak 1 is labeled as the 1323 (3 + 1) multi-photon process through the intermediate Rydberg state E ∼ 1 A 1 ′ . The phenomena of channel switching are found in the slow electron kinetic energy distributions. Our calculations and experimental results indicate that the stretching vibrational mode of ammonia molecules varies with channels, while the umbrella vibration does not. In addition, we consider and discuss the ac-Stark effect in a strong laser field. Peaks 5 and 6 are marked as (2 + 2 + 1) and (2 + 2 + 2) above threshold ionization processes in the fast electron region.

Mechanical weeding is an efficient weeding method, which is of considerable significance to the paddy field ecosystem. However, traditional mechanical weeding methods can cause seedling damages due to the bending phenomenon of the seedling lines. Introducing computer vision and control technology to traditional mechanical weeding methods can help the system diagnose the bending phenomenon and avoid crushing the seedlings. In this paper, we propose a deep-learning-based method of seedling line bending diagnosis and guidance line extraction. To prove the proposed method effective in the mechanical weeding system, we choose the Faster Region-based Convolutional Network (R-CNN) and Single Shot MultiBox Detector (SSD) as the representative models of the single-phase method and the two-phase method. With a novel dataset of rice seedling images established, we compare and analyze the confidence and real-time performance of the trained models. The experimental results show that the Faster R-CNN model is better in terms of accuracy, yet the SSD model has more advantages in the speed. Comprehensively considering the system requiring and model performances, the SSD model is a better choice in the automatic rice avoidance system.

In this work, we used atomistic level simulations to study water molecules confined between an epoxy layer and alumina substrate. Water is responsible for many complex reactions at the interface of substrate, which makes understanding characteristic properties of water at this particular confinement essential. Three different confinement sizes were selected. The substrate is hydroxylated gamma alumina and the organic coating layer is constructed with epoxy molecules. Different properties such as density, mobility and displacement, inter-molecular structures, power spectra, and hydrogen bond energy of water molecules were obtained. The results are studied in connection with the size of confinement. It is shown that the properties of water in this type of confinement are different from the bulk water and as the size of confinement decreases, some of the unique behaviors of water molecules are revealed.

Fibers have been commonly used to enhance the cracking resistance of asphalt mixtures. However, the reinforcing actions of different fibers have presented diverse effects. Therefore, three kinds of fibers, including glass fibers, basalt fibers and steel fibers, were selected to investigate their influences on the low temperature properties and cracking resistance of asphalt mixtures in this paper. Indirect tensile testing (IDT) was conducted to obtain basic properties such as the Poisson’s ratio and moduli. The digital image correlation (DIC) technique was employed to measure the deformation and strain. The crack inhibition action was evaluated by the failure time. The results showed that the fiber type has no influence on the Poisson’s ratio of the mixture. However, the addition of fibers remarkably affects the mixture modulus. The modulus and ultimate tensile strength of the reinforced mixture decline after the addition of fibers. The gaps between the compressive and tensile moduli are also increased by the addition of fibers. Moreover, the addition of fibers not only substantially improves the mixture ductility but also delays the fracture process. The fiber reinforced asphalt concrete (FRAC) presents a higher fracture energy (FE) and dissipated creep strain energy (DCSE) than that of the control concrete. Among the selected fibers, basalt fibers exhibit optimal crack resistance performance, while steel fibers are not recommended due to their smooth appearance.

The recent development of the cold spray method has made it possible to deposit dense coating with good adhesion and with almost no change in the microstructure, which is promising in repairing damaged Al-based aircraft skin. In this work, the in-situ shot-peening-assisted low-pressure cold spray method was used to deposit Al-based dense coatings with good mechanical and corrosion protection properties on AA 2024-T3 alloy. The detailed microstructure, coating adhesion, and corrosion protection performance were systematically investigated. A dense microstructure with low porosity ( 45 MPa) is achieved for the coatings. By comparison, Al 5083 coating exhibited the optimum mechanical properties. The Al and Al 5083 coatings reveal similar pitting resistance and repassivation ability. During long-term immersion test (>480 h) the corrosion resistance of Al 5083 coating surpassed that of CP Al coating. In conclusion, Al 5083 coating has a good combination of mechanical and anti-corrosion properties.

The molecular dynamics (MD) method can be a reliable tool for studying of organic coating/metallic substrate systems, however its accuracy is limited to the force field governing the dynamics of systems. These systems can be divided into three parts: (i) organic phase, (ii) substrate, (iii) interface between the organic phase and substrate. In this work, three recent ReaxFF descriptions were selected. A set of complex experimental data and density functional calculations was selected as the reference point. The density and structural analysis of a wide range of crystalline organic compounds were studied. The density, structural analysis, and self-diffusion constant of water at room temperature were obtained. The glass transition temperature of three different cross-linked epoxy were obtained and compared with the reported experimental results. The interaction energies of different configurations of epoxy and water over an alumina substrate were studied. Additionally, the reaction of water with aluminum was studied. The accuracy of these ReaxFF descriptions in reproducing the reference data was assessed. The results show there is a single ReaxFF description for accurate simulation of C/H/N/O/Al systems, which enables atomistic simulations of complex epoxy coatings/aluminum substrates systems.

New insights on the effect of nature and number of polyelectrolyte (PE) shells on active anticorrosion potential of microcontainers (MCs) applied as pH-sensitive reservoirs in coatings for the protection of AA2024-T3 is reported. Mesoporous silica particles (MSP) were loaded with benzotriazole (BTA) and shelled with different polyelectrolyte multilayers (PEM), demonstrating pH sensitivity. Weak-weak polyelectrolyte (W-W PE) shells allow immediate release of inhibitor, but weak-strong polyelectrolyte (W-S PE) shells encourage slower, more controlled and prolonged release, as revealed by release profiles of BTA from microcontainers. Active anticorrosion protection characterizations of the coatings doped with microcontainers were carried out by electrochemical techniques (EIS, SVET) and salt spray tests. Results reveal dependence of active properties of coatings on the nature and number of polyelectrolyte multilayers of microcontainers. We anticipate that proper choice of PEMs on smart containers can aid controlled functionalization of active feedback systems.

The Generalized Iterative Closest Point(G-ICP) algorithm is a high-precision point cloud registration algorithm, which uses Euler angles to parameterize a rotation matrix. However, Euler angle parameterization has singularity at a specific angle, which leads to application limitations. In this paper, a new G-ICP algorithm has been proposed, in which the Lie algebra on so(3) is used to parameterize a rotation matrix and the Gauss-Newton method is employed to optimize the objective function of the G-ICP algorithm. The experimental results have demonstrated that our method performs well compared with the state-of-the-art G-ICP alorithm [1] and simultaneously holds better estimation accuracy of pose with fast convergence speed in the open RGB-D TUM datasets.

Automated and coordinated vehicle technology has becoming increasingly prevalent. In this paper, in terms of the fuel consumption and pollutant emissions, we proposed an S-velocity curve regulation, combined with a sinusoidal scenario to evaluate four classic vehicle platoon autopilot control algorithms. The simulation studies of different scenarios are implemented in an integrated simulation platform PLEXE, which is developed based on SUMO and OMNeT ++. For emission model in SUMO, we utilize PHEMlight, which is a simplified version of the Passenger car and Heavy duty vehicle Emission Model (PHEM) to replace the default one. Numerical simulations demonstrate that, when the leader driving with S-velocity curve, Cooperative Adaptive Cruise Control (CACC) proposed by PATH project has higher fuel efficiency and lower CO 2 emission than other three control laws. Moreover, this CACC algorithm can maintain string stability and more consistent operations (in terms of velocities and inter-vehicle gaps) even under sinusoidal scenario changed frequently.

An innovative method was put forward to fabricate superhydrophobic surface based on nanostructured zinc rich coatings via modifying the rough surface with perfluorodecyl triethoxysilane solution. The obtained superhydrophobic surface not only displays a static water contact angle of 153°and water sliding angle of 7°, but also exhibits an excellent reparability and self-cleaning ability during the field test. Water immersion test and electrochemical measurements demonstrated that this modification can improve the anticorrosion performance of the coating.

Highly dispersed nanometer BiVO4 on attapulgite (ATP) as hybrid inhibitor pigment was prepared using chemical bath deposition. Microscopy analysis shows that nanometer BiVO4 particles uniformly grow on attapulgite. The immersion and polarization tests show that ATP-BiVO4 inhibits corrosion of aluminium alloy 2024-T3. The EIS results indicate that the coating resistance of ATP-BiVO4 containing epoxy coating is approximately two orders of magnitude higher than that of the epoxy coating containing only attapulgite. The enhanced corrosion protection ability of ATP-BiVO4 containing epoxy coating can be ascribed to the combination of the barrier effect of ATP-BiVO4 and the inhibition effect of the released vanadate at the coating/substrate interface. The deposition of BiVO4 with inhibition ability on fillers provides a new way to develop hybrid inhibitor pigment.

Using organic coatings with high barrier property in combination with active corrosion protection can improve corrosion protection of aluminum alloys. In this work, 3-Amino-1,2,4-triazole-5-thiol (ATAT) was used as organic inhibitor in developing anticorrosion coatings for AA2024-T3. The delivery of ATAT was achieved by using smart microcontainers with ATAT that respond to pH change caused by corrosion reaction at the coating-substrate interface. The developed coatings with low concentration of smart microcontainers showed a slight reduction of barrier properties, but gained active corrosion protection capability. The resistance of the coatings reduced the rate of penetration of corrosive species and the active corrosion protection stopped the damaging reactions at the coating-substrate interface. The active corrosion protection is also evident in the case of coatings with mechanical damages, when the barrier property of coatings is compromised. Waterborne coatings with smart microcontainers for delivery of ATAT exhibited enhanced performance for corrosion protection of AA2024-T3.

This paper aims to investigate safe diagnosis of fuzzy discrete-event systems (FDESs) under the decentralized framework. The notion of safe codiagnosability of FDESs is formalized to capture the property of systems that each occurrence of failures can be detected by at least one local diagnoser with a certain degree before any unsafe forbidden operation is executed. After introducing a fuzzy automaton called the recognizer to distinguish the forbidden strings from the illegal language, a safe codiagnoser is constructed to perform decentralized safe diagnosis of FDESs. In particular, a necessary and sufficient condition of safe codiagnosability of FDESs is derived, which extends the existing main results of safe diagnosability of FDESs from the centralized setting to the decentralized case.

This paper addresses the reliable predictability of decentralized discrete event systems (DESs) in face of possible unavailability of some local agents. The notion of k-reliable copredictability is formalized. Roughly speaking, a decentralized system distributed at $m$ local sites being k-reliably copredictable $(1\leq k\leq m)$ means that the prediction performance will not be degraded even when m- $k$ local agents are unavailable. In order to perform the reliable prediction, an automaton called reliable copredictor is constructed from the given decentralized system. Finally, a necessary and sufficient condition for the k-reliable copredictability of DESs based on the reliable copredictor is presented, and an approach for verifying the k-reliable copredictability of DESs is developed.

In this paper, based on Inertial Measurement Unit (IMU) preintegration, a pose estimation algorithm for Visual-Inertial Odometry (VIO) system has been investigated. Firstly, we developed the kinematic equation of acceleration and angular velocity of IMU. To avoid the re-integration caused by the change of the system states, the IMU measurements are preintegrated on the Riemannian manifold of rotation. Furthermore, we studied the propagation characteristic of noise and derived the state transition equation of the noise. So the influence of noise on pose estimation can be dramatically reduced. Compared with the famous Okvis algorithm, experimental results on two public datasets of EuRoC show that the proposed IMU preintegration algorithm achieves good estimation median of translation error with 0.14 m, which is better than Okvis with 0.24 m.

In this paper, we study the decentralized control problem for nondeterministic discrete-event systems DESs under bisimulation equivalence. In order to exactly achieve the desired specification in the sense of bisimulation equivalence, we present a synchronous composition for the supervised system based on the simulation relation between the specification and the plant. After introducing the notions of simulation-based controllability and simulation-based coobservability, we present the necessary and sufficient condition for the existence of a decentralized supervisor such that the controlled system is bisimilar to the specification, and an algorithm for verifying the simulation-based coobservability is proposed by constructing a computational tree.

Since fuzzy discrete-event systems (FDESs) were significantly brought forward, the study of FDESs has received increasing attention recently. This paper addresses the safe diagnosability under the framework of FDESs. The contributions are threefold. First, the notion of safe diagnosability for fuzzy systems is formalized. A safe diagnosable FDES means that not only each failure can be detected in terms of fuzziness, as well as the detection must be completed before any unsafe operation is executed. Then, a necessary and sufficient condition of safe diagnosability of FDESs is proposed by constructing the safe diagnoser. Finally, we present an algorithm for verifying the safe diagnosability of FDESs based on a constructive nondeterministic automaton, namely verifier. It is worth noting that both constructing the verifier and verifying the safe diagnosability of FDESs can be realized with a polynomial complexity.

The galvanic corrosion of the coupled Al2Cu and Al as well as Al3Fe and Al in 0.005 M NaCl in and without the presence of cerium cinnamate was studied. Scanning vibrating electrode technique and scanning ion-selective electrode technique were used to measure the distribution of current densities and pH. The results indicate that cerium cinnamate played inhibiting effect on the coupling corrosion of Al2Cu–Al and Al3Fe–Al. For Al2Cu–Al, the inhibition was mainly influenced by the production of cerium oxide/hydroxide on Al2Cu surface. However, for Al3Fe–Al, the inhibition was mainly influenced by the adsorbed cerium cinnamate on the Al3Fe surface.

A new corrosion inhibitor, cerium tartrate, was synthetized. The inhibition behavior of cerium tartrate for 2024-T3 aluminum alloy was investigated in 0.05 M NaCl solution. The immersion tests indicate that the corrosion of Al2CuMg phase was well inhibited. The electrochemical results show that both anodic and cathodic inhibitions are present during the corrosion process. The surface characterizations reveal that the protective film of cerium tartrate inhibits the dealloying of Al2CuMg phase in the initial stage, and then cerium ions transform to cerium oxide/hydroxides and appear at the Al2CuMg phase, blocking the further corrosion at those corrosion sites.

Microcapsules containing core materials are promising component for developing self-healing coatings. In the present work, urea-formaldehyde capsule containing core material with size of micrometer was prepared by in-situ encapsulation method. The morphology of the microcapsules was characterized by scanning electron microscopy. A corrosion inhibitor, benzotriazole, was successfully loaded on the outside of microcapsules by layer-by-layer assembling using polyelectrolytes. Thus, the modified microcapsules are promising to provide healing ability combined by release of interior core material and exterior corrosion inhibitor.

This work presents the silane-based sol–gel coatings that prepared by in situ doping 8-hydroxyquinoline as corrosion inhibitor for the protection of AA 2024-T3. The morphology and thickness of the sol–gel coatings were observed by scanning electron microscope (SEM). Immersion tests and electrochemical impedance spectroscopy (EIS) were used to study the corrosion resistance of the blank and 8-hydroxyquinoline doped sol–gel coatings. The results indicate that the addition of 8-hydroxyquinoline effectively improved the corrosion resistance of the sol–gel coatings. The self-healing effect of 8-hydroxyquinoline on the corrosion in the defects of sol–gel coating was assessed by scanning vibrating electrode technique (SVET) and proved by the results of energy-dispersive X-ray spectroscopy (EDS) mapping.

Safe diagnosis was viewed as the first necessary step of fault-tolerant supervision of discrete event systems (DESs), and a method of safe diagnosis for stochastic DESs was proposed by constructing safe diagnosers in the literature. However, the complexity of constructing such safe diagnosers is exponential. In this paper, we present an algorithm to perform safe diagnosis of stochastic DESs by constructing a nondeterministic automaton called the safe verifier. The necessary and sufficient condition for safe diagnosability of stochastic DESs is proposed. It is worth noting that the complexity of constructing the safe verifier is polynomial in the number of states and events of the system.

In this paper, an improved distributed model predictive control (MPC) algorithm subject to actuator delay of vehicles in cooperative adaptive cruise control (CACC) system is proposed. Firstly the traditional model predictive control approach is analyzed, which solves the incremental control input by transforming the MPC problem with constraints into a standard quadratic programming (QP) problem and introduces a slack variable to soften constraints. However, the traditional MPC controller cannot meet the requirement of tracking performance and safety when the actuator delay is taken into account. Therefore, an improved MPC algorithm using the method of dynamic matrix control (DMC) is proposed. Numerical simulations show that the tracking performance of the improved MPC algorithm can be maintained in different actuator delay while the performance of traditional one becomes poor or even unstable, which demonstrates the effectiveness of the proposed algorithm.

In this manuscript, we have developed an efficient spraying method to successfully fabricate a series of flower-like coordination polymers (CP) microparticles, including Co/BDC (1,4-benzenedicarboxylate) metal organic frameworks (MOF) and infinite coordination polymers (ICP) microparticles, as well as Ni-Co/BDC MOF and Zn/DOBDC (2,5-dioxido-1,4-benzenedicarboxylate) MOF. The spraying method has shown high efficiency and universality in synthesizing the flower-like CP. The crystalline structure can be adjusted by varying the solvent composition in the spraying process. SEM observation demonstrated the MOF and ICP microparticles possess the similar flower-like structure, which is composed of nanoflakes with smooth surface, and the flower-like microparticles could be monodisperse with as low as 5% polydispersity. Moreover, the fabrication of the flower-like CP microparticles by spraying has a wide operation window, because there is no need to precisely control the experiment conditions, like solvents, concentration, and spray order. Due to the practicality of spray technique, this work would pave the way for the manufacture of the flower-like materials and have great potential in applications of catalysis, sensor, energy storage, and so on.

Strong field sequential ionization of symmetric-top CH

In this paper, the verification issue for the predictability of decentralized discrete event systems (DESs) is investigated, in which the detection information may be decentralized among physically separated sites. After the predictability for decentralized DESs is formalized by the notion of copredictability, which describes the ability of the involved system that the failure events can be predicted prior to their occurrences by at least one local observer, a nondeterministic automaton, namely coverifier, is constructed to achieve the performance of the prediction. Then a necessary and sufficient condition for verifying the copredictability of DESs based on the coverifier is proposed. In particular, the complexity for realization of failure prediction is analyzed. It is proved that for a given decentralized system, the coverifier can be constructed with a polynomial complexity, and the verification for its copredictability can be completed within polynomial time.

The navigation output accuracy of SINS / GPS integrated navigation system will decline when GPS is not available. Zero Velocity Update (ZUPT) technology is used for the error correction in this paper. As a relevant algorithm, the zero velocity detection algorithm is applied in the carrier movement. This method has achieved an integrated navigation system filtering algorithm based on ZUPT. The simulation and experiment results show that the algorithm effectively improves the accuracy of navigation by limiting the velocity value of GPS in zero-velocity condition.

The interaction of CH3I molecules with 100 fs 800 nm linearly polarized laser fields has been investigated at the intensity region from 2.6 × 1014 to 5.8 × 1014 W/cm2 by means of a velocity map imaging method. The kinetic energy distribution of the various atomic fragment ions I q+ (q = 1–3) has been measured and reproduced by a fit of multiple Gaussian functions. Several dissociative ionization and Coulomb explosion channels were identified for I q+ (q = 1–3). As expected for a geometric alignment dominated interaction process the anisotropic angular recoil distributions of the atomic ion fragments are peaked in the laser polarization direction. The kinetic energy release (KER) of I q+ (q = 1–3) depending upon the laser intensity has been investigated. The relative weight of the various contributions from the identified dissociative ionization (DI) and Coulomb explosion (CE) channels is found to depend strongly on the laser intensity.

This paper aims to investigate the correctability of stochastic discrete-event systems (DESs) equipped with a probabilistic structure to estimate the likelihood of events occurring. The notion of k-step corrective probability is formalized by using the representation of decision trees to describe the possibility that the stochastic system may recover to accepted states from the current state within k steps. By introducing the strategy of adjusting the transition probability of the current state, a correction mechanism is presented for stochastic systems to achieve the maximal k-step corrective probability. In addition, an approach for the computation of supremal corrective probability is developed by constructing the decision tree after introducing the infinitely expandable states. Finally, an illustrative example is provided.

In this paper, the decentralized predictability of discrete event systems (DESs) is investigated. The notion of copredictability of DESs is formalized under the decentralized framework to capture the feature of copredictable DESs that the occurrences of failure events can be predicted in advance based on at least one local observation. The relationships with the notions of predictability and codiagnosability of DESs are analyzed. It is deducted that copredictability is weaker than predictability but stronger than codiagnosability. In order to achieve the performance of the prediction, the copredictor is constructed from a given decentralized system, in which a family of local prediction components are employed to deal with the local observations. In particular, a necessary and sufficient condition for the copredictability of DESs is presented, which generalizes the main results of predictability of DESs from the centralized framework to the decentralized case.

A new axiomatical definition of entropy measure for interval-valued intuitionistic fuzzy set based on distance is firstly proposed, which is consistent with the axiomatical definition of fuzzy entropy introduced by De Luca and Termini. Then, we present some new entropy measures for interval-valued intuitionistic fuzzy sets (IvIFSs) and discuss their relationships with similarity measures and inclusion measures for IvIFSs. Also, we prove that the presented entropy measures, the similarity measures and the inclusion measures of IvIFSs can be transformed into each other by their axiomatical definitions. Finally, several numerical examples are given to demonstrate that the proposed new entropy measures for IvIFSs are more intelligible in representing the degree of fuzziness of IvIFSs than the existing ones.

The coupling of pure Al, Cu and Mg wires and the coupling of Al 2 CuMg intermetallic rod and Al wire were used to study the corrosion process of Al 2 CuMg phase particles in 2024-T3 aluminium alloy, by means of scanning vibrating electrode technique (SVET) and scanning ion-selective electrode technique (SIET). The results show the preferential dissolution of Mg in the coupling of Al, Cu and Mg. Al 2 CuMg was found to show self-dissolution when coupled with Al, rather than anodic dissolution. According to the results, a mechanism of early corrosion of S phase in AA2024-T3 is proposed.

Electrically conductive coatings are required for static charge dissipation in power ground network. In the present investigation electrically conductive nanocoatings were prepared by the incorporation of graphite, nano-SiO2 concentrate, acrylic nanoemulsion and fluorocarbon emulsion onto the waterborne epoxy polymer. The nanosize distribution of nano-SiO2 concentrate and nanoemulsion was characterized with laser diffraction analyzer and scanning electron microscopy (SEM). From the results of SEM image, the graphite particles were well distributed in conductive coating. The corrosion resistance and thermal stability of nanocoatings were comparatively studied by SEM and thermogravimetry (TG). The corrosion-inhibiting properties of the conductive nanocoatings were investigated by salt immersion test. The measurements of contact angle, bonding strength and heat-freeze charge demonstrated that 1.5–2.0 wt% nanoparticles improve the resistance to pollution, adherence and resistance to heat-freeze charge of conductive nanocoatings. The measured results of surface electric resistance of nanocoatings demonstrated that a small amount of nano-SiO2 particles could enhance the conductivity in the corrosive environment.

A fuzzy approach to perform diagnosis of fuzzy discrete event systems (FDESs) is proposed by constructing diagnosers, which may more effectively cope with the problems of vagueness and fuzziness arising from failure diagnosis of fuzzy systems. However, the complexity of constructing this kind of diagnosers is exponential in the state space and the number of fuzzy events of the system. In this paper, we present an algorithm for verifying the diagnosability of FDESs based on the construction of a nondeterministic automaton called F-verifier instead of diagnosers. Both the construction of F-verifiers and the verification of diagnosability of FDESs can be realized with a polynomial-time complexity.

This paper presents an enhanced approach for multiattribute decision making with interval-valued intuitionistic fuzzy assessing values for each alternative. To efficiently deal with the interval-valued intuitionistic fuzzy multiattribute decision making problem with partially or completely unknown weight information, we construct several optimization models based on minimizing the distance between each alternative and positive ideal solution to obtain the optimal weight of each attribute. Also by employing the weighted grey relational coefficient of each alternative with respect to the ideal solution, the full ranking of all the alternatives can be obtained and the most desirable one can be selected.

In this work, we mainly investigate the NH3 molecular multiphoton ionization process by using the photoelectron velocity map imaging technique. Under the condition of femtosecond laser (wavelength at 800 nm), the photoelectron images are detected. The channel switching and above-threshold ionization (ATI) effect are also confirmed. The kinetic energy spectrum (KES) and the photoelectron angular distributions (PADs) are obtained through the anti-Abel transformation from the original images, and then three ionization channels are confirmed successfully according to the Freeman resonance effect in a relatively low laser intensity region. In the excitation process, the intermediate resonance Rydberg states are C ∼ A 1 ′ 1 (6 + 2 photons process), B ∼ E ″ 1 (6 + 2 photons process) and C ∼ A 1 ′ 1 (7 + 2 photons process), respectively. At the same time, we also find that the photoelectron angular distributions are independent of laser intensity. In addition, the electrons produced by different processes interfere with each other and they can produce a spider-like structure. We also find ac-Stark movement according to the Stark-shift-induced resonance effect when the laser intensity is relatively high.

A study quantifying the effects of different copper (Cu) concentrations (50, 200, 800 and 1,000 mg kg−1 Cu) on Cu bioaccumulation and physiological responses of Spartina alterniflora was conducted. Plant biomass and Cu accumulation were determined. Plant height, tiller number, chlorophyll, leaf electrolyte leakage rate (ELR), malondialdehyde (MDA), proline, soluble sugar, and organic acids were also measured. The results showed that S. alterniflora mainly accumulated Cu in fine roots. No significant changes of biomass of fine roots were detected except for obvious reduction under 1,000 mg kg−1 Cu. In leaves, rhizomes and fine roots, the highest Cu accumulations were detected under 800 mg kg−1 Cu. The highest Cu accumulation in stem was revealed under 200 mg kg−1 Cu. Plant height decreased under 1,000 mg kg−1 Cu; chlorophyll content reduced under >50 mg kg−1 Cu; levels of ELR and MDA increased under >200 mg kg−1 Cu. However, osmotic components such as proline and soluble sugar were accumulated to cope with higher Cu stresses (800 and 1,000 mg kg−1). Further, oxalic and citric acids were positively related with Cu contents in leaves and stems, suggesting that oxalic and citric acids may be related to Cu detoxification in aboveground parts of S. alterniflora. However, in above and belowground parts, no detoxification function of ascorbic and fumaric acids was observed due to unchanged or decreased trend under Cu stress.

The epoxy nanocomposites with similar amines (CH3(CH2)17NH2 and CH3(CH2)17N(CH3)3Cl) treated montmorillonite clays have been investigated by wide-angle X-ray scattering, transmission electron microscopy (TEM), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). Different nanocomposite structures, intercalation and exfoliation were formed by the reaction of octadecyltrimethylammonium chloride-exchanged and octadecylamine-exchanged clays with epoxy resin and phenalkamine as the curing agent, respectively. Results showed that the exfoliated nanocomposite can be obtained when octadecylamine with the lower polarity was used as a modifier. However, the intercalated nanocomposite can be obtained when octadecyltrimethylammonium chloride with higher polarity was used as a modifier.

The quantitative adsorption behavior of a hyperdispersant onto nano-TiO2 particles has been characterized by using FTIR (Fourier transform infrared) spectroscopy, NMR (nuclear magnetic resonance) and a negative adsorption method. The intrinsic adsorbed amount of hyperdispersant was (1.05±0.09) mg/m2. Thickness of the adsorbed layer was (4.66±0.42) nm. There was (74±7)% wt water in the adsorbed layer. In the hyperdispersant molecule, the anchoring group of the amide group attached firmly to the nano-TiO2 particles, and the solvatable chains of comb-type structure exhibited the effective steric stabilization.

Ionization and dissociation of 2- and 3-methyl cyclopentanones have been investigated in molecular beams by their irradiation with intense 394 and 788 nm laser fields with pulse duration of 90 fs and intensity of 3 × 10 13 –4 × 10 14 W/cm 2 . The analysis of the resulting mass spectra allowed us to discern the effects of methyl substitution and its position on the outcome of ionization/dissociation processes induced by the intense femtosecond laser field. Generalized Keldysh-Faisal-Reiss (g-KFR) and ab initio G3(MP2,CCSD)//B3LYP/6–31G ∗ /RRKM theoretical calculations helped to uncover the formation mechanism of major ionic fragments observed in the mass spectra including C 5 H 10 + , C 4 H 6 O + , C 3 H 3 O + , C 3 H 4 O + , C 3 H x + , and C 2 H x + .

This study presents a new early warning evaluating method and decision mechanism for urban emergency in which the risk factors are easily assessed by fuzzy numbers. By using the fuzzy preference relation matrix and the extended fuzzy AHP, the relative weight of each risk factor can be estimated. Then we evaluate the total fuzzy risk value by aggregating the severity of loss of risk factor and the relative weight of risk factor. According to the similarity between the fuzzy comprehensive risk value and the pre-established risk grade, the early warning grade of the urban significant emergency can be determined for urgent emergency decision-making.

A study quantifying the interactive effects of cadmium (Cd) and carbon nanotubes (CNTs) on plant growth and Cd accumulation of pot-cultured Spartina alterniflora was conducted. The experiment consisted of two Cd levels (50, 200 mg kg−1) as well as two CNTs levels (800, 2,400 mg kg−1). As expected, CNTs alleviated higher Cd stress (200 mg kg−1) due to restored shoot growth reduction, retrieved water content and resumed plant height. Furthermore, CNTs mitigated the deleterious effects of Cd stress through improving K+ and Ca2+ contents, while reducing Na+/K+ and Na+/Ca2+ ratios, regardless of the level of Cd stress. The proline contents in combined Cd and CNTs treatments were lower than Cd alone, suggesting that CNTs could reduce production of organic solutes under Cd stress. The results also showed higher Cd accumulation in roots than shoots, and both were improved by CNTs, except inhibition in roots under higher Cd stress (200 mg kg−1). It appears that CNTs may not significantly affect negative Cd effects on growth of S. alterniflora, but improve total Cd accumulation under lower Cd stress (50 mg kg−1). However, under higher Cd stress (200 mg kg−1), CNTs restored the reduced plant growth, improved and reduced Cd accumulation in shoots and roots, respectively. Therefore, the effects of CNTs on plant growth and Cd accumulation are different, and levels of Cd stress should be considered when evaluating the combined application of CNTs and S. alterniflora on phytoremediation of Cd pollution.

A two-stage process was used to produce nano-composite epoxy coatings. The first step involved preparing nano-Al concentrates with high concentration and low viscosity, and the second step produced nano-composite epoxy coatings by mixing the nano-Al concentrates and epoxy resin. Later, the coating was examined with immersion and salt spray tests. The coatings were characterized by electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The results showed that the 5% nano-Al significantly improves the corrosion resistance of the coatings. There are two effects of nano-Al on the coating. Nano-Al is corroded initially to protect the substrate from corrosion, and then the aluminum oxide and aluminum hydroxide were produced after corrosion of nano-Al, which hindered the transmission of corrosion fluid into the coatings.

Polyaniline (PANI) was covered on the surface of ultra-short glass fibers uniformly by in situ polymerization of aniline. Epoxy coatings with different contents of PANI ultra-short glass fibers and ultra-short glass fibers were formulated and their protection abilities were evaluated by means of open-circuit potential, electrochemical impedance spectroscopy and salt spray test. The results showed that the PANI ultra-short glass fibers had a significant inhibitive effect and its best volume fraction was10% in epoxy coating. XPS results indicated that a dense, stable passive oxide film of Fe2O3/Fe3O4 was formed on the steel surface beneath the coating.

Nonadiabatic alignment by intense nonresonant laser fields is a versatile technique to manipulate the spatial direction of molecules. By solving the time-dependent Schrodinger equation numerically the degree of alignment of the molecules initially in different rotational state are calculated and the results show that the degree of alignment strongly depends on the initial rotational state. Thus, the present study indicates that, for obtaining a high degree of alignment for molecules, appropriate selection of molecular rotational states is necessary.

Epoxy coatings containing different volume fractions of zinc phosphate have been successfully prepared and their inhibitive properties have been studied by electrochemical impedance spectroscopy (EIS) and immersion tests. The results show that zinc phosphate can improve the protection ability of epoxy coatings and its best volume fraction is 30%. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) results indicate that the presence of zinc phosphate can form an inhibiting film which is composed of the phosphating film of FePO4, Fe2O3, and FeO, as well as the shielding film of zinc phosphate on the steel surface. (C) 2012 Elsevier Ltd. All rights reserved.