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Multiview clustering plays an important part in unsupervised learning. Although the existing methods have shown promising clustering performances, most of them assume that the data is completely coupled between different views, which is unfortunately not always ensured in real-world applications. The clustering performance of these methods drops dramatically when handling the uncoupled data. The main reason is that: 1) cross-view correlation of uncoupled data is unclear, which limits the existing multiview clustering methods to explore the complementary information between views and 2) features from different views are uncoupled with each other, which may mislead the multiview clustering methods to partition data into wrong clusters. To address these limitations, we propose a tensor approach for uncoupled multiview clustering (T-UMC) in this article. Instead of pairwise correlation, T-UMC chooses a most reliable view by view-specific silhouette coefficient (VSSC) at first, and then couples the self-representation matrix of each view with it by pairwise cross-view coupling learning. After that, by integrating recoupled self-representation matrices into a third-order tensor, the high-order correlations of all views are explored with tensor singular value decomposition (t-SVD)-based tensor nuclear norm (TNN). And the view-specific local structures of each individual view are also preserved with the local structure learning scheme with manifold learning. Besides, the physical meaning of view-specific coupling matrix is also discussed in this article. Extensive experiments on six commonly used benchmark datasets have demonstrated the superiority of the proposed method compared with the state-of-the-art multiview clustering methods.

Incomplete multiview clustering (IMC) methods have achieved remarkable progress by exploring the complementary information and consensus representation of incomplete multiview data. However, to our best knowledge, none of the existing methods attempts to handle the uncoupled and incomplete data simultaneously, which affects their generalization ability in real-world scenarios. For uncoupled incomplete data, the unclear and partial cross-view correlation introduces the difficulty to explore the complementary information between views, which results in the unpromising clustering performance for the existing multiview clustering methods. Besides, the presence of hyperparameters limits their applications. To fill these gaps, a novel uncoupled IMC (UIMC) method is proposed in this article. Specifically, UIMC develops a joint framework for feature inferring and recoupling. The high-order correlations of all views are explored by performing a tensor singular value decomposition (t-SVD)-based tensor nuclear norm (TNN) on recoupled and inferred self-representation matrices. Moreover, all hyperparameters of the UIMC method are updated in an exploratory manner. Extensive experiments on six widely used real-world datasets have confirmed the superiority of the proposed method in handling the uncoupled incomplete multiview data compared with the state-of-the-art methods.

The connection between two submarine pipelines is usually made by welding. In the process of welding, the incomplete penetration, incomplete fusion, porosity, cracks and other welding defects are hardly preventable. The incomplete penetration defects at the root of pipeline girth welds can greatly reduce the safety of submarine pipelines and increase the risk of pipeline failure. In this paper, the safety assessment of incomplete penetration defects at the root of pipeline girth welds are studied. Firstly, a novel model of incomplete penetration defects at the root of girth weld pipelines is provided. Then, an analytical solution of the novel model is obtained according to stress function method. Next, the residual strength equation of the incomplete penetration defects at the root of pipeline girth welds is derived based on the analytical solution. In the end, the calculated results of the residual strength equation are verified by finite element method (FEM) and experiment. The results indicate that the calculated values are in good agreement with the FEM and experiment. In addition, the results indicate that the safety assessment method of incomplete penetration defects at the root of pipeline girth welds is feasible. It is beneficial for the safety assessment of pipelines with incomplete penetration defects.

The clinical use of daunomycin is restricted by dose-dependent toxicity and low specificity against cancer cells. In the present study, modified superparamagnetic iron oxide nanoparticles were employed to load daunomycin and the drug-loaded nanospheres exhibited satisfactory size and smart pH-responsive release. The cellular uptake efficiency, targeted cell accumulation, and cell cytotoxicity experimental results proved that the superparamagnetic iron oxide nanoparticle-loading process brings high drug targeting without decreasing the cytotoxicity of daunomycin. Moreover, a new concern for the evaluation of nanophase drug delivery's effects was considered, with monitoring the interactions between human serum albumin and the drug-loaded nanospheres. Results from the multispectroscopic techniques and molecular modeling calculation elucidate that the drug delivery has detectable deleterious effects on the frame conformation of protein, which may affect its physiological function.

5,10,15,20-tetra-(N-methyl-2-pyridyl)porphyrin (TMPyP2) was always paid little attention because it has relatively low DNA-binding affinity and photocytotoxicity compared with its positional isomer 5,10,15,20-tetra-(N-methyl-4-pyridyl)porphyrin (TMPyP4). Inspired by the previous successful results on higher bioactivities of ligands with larger aromatic surfaces, herein, 5,10,15,20-tetra (phenyl-4-N-methyl-2-pyridyl) porphyrin (TPMPyP2), a TMPyP2-like porphyrin with enlarged planar substituents, was designed and successfully synthesized. Results from spectral experiments and molecular docking calculation suggest that TPMPyP2 could partially overcome the steric hindrance of TMPyP2, with more favorable DNA-binding mode and lower molecular binding energy (M.B.E). Meanwhile, cell photocytotoxicity research indicates that TPMPyP2 shows higher antitumor potency than TMPyP2, which allowed the previous conclusion that the higher G-Quadruplexes DNA binding affinity would be related to better photocytotoxicity.

Intensive reports allowed the conclusion that molecules with extended aromatic surfaces always do good jobs in the DNA interactions. Inspired by the previous successful researches, herein, we designed a series of cationic porphyrins with expanded planar substituents, and evaluated their binding behaviors to G-quadruplex DNA using the combination of surface-enhanced raman, circular dichroism, absorption spectroscopy and fluorescence resonance energy transfer melting assays. Asymmetrical tetracationic porphyrin with one phenyl-4-N-methyl-4-pyridyl group and three N-methyl-4-pyridyl groups exhibit the best G4-DNA binding affinities among all the designed compounds, suggesting that the bulk of the substituents should be matched to the width of the grooves they putatively lie in. Theoretical calculations applying the density functional theory have been carried out and explain the binding properties of these porphyrins reasonably. Meanwhile, these porphyrins were proved to be potential photochemotherapeutic agents since they have photocytotoxic activities against both myeloma cell (Ag8.653) and gliomas cell (U251) lines.

Polyimide (PI) films filled with K0.5Na0.5NbO3 particles at different weight 0wt%,5wt%,10wt%,15wt% and 20wt% had been prepared by in-situ dispersion polymerization process in this article. then we measured morphology and dielectric properties. when the mass fraction of KNN reach 20%, its dielectric constant achieve 4.9(100Hz) with the dielectric loss tangent value is less than 0.025 (100 Hz).it Shows the good insulating properties.

Polyimide nanocomposite insulating materials are widely used in electrical and electron engineering owing to their outstanding electrical, mechanical, thermal, and wear-resistance properties. Polyimide/silica (PI/SiO2) nanocomposites have been prepared by the polymerization process of adding tetraethoxysilane (TEOS) and the coupling agent isocyanatopropyltriethoxysilane (ICTOS) in polyimide. The effects of SiO2addition on the microstructure and the dielectric property of nanocomposite films were investigated. It was found that the silica particles were well dispersed in PI matrix and the sizes of SiO2particles in the hybrid films range from 20 nm to 30 nm for 5-15 wt% SiO2loading in the matrix. The dielectric constant and the dielectric loss (tan δ) of these films increased with the increase of the content of silica particles.

This paper introduces a practical and cross-platform virtual electrical experimental tool (VEET) based on an off the shelf game engine called Unity3D which is powerful and flexible to develop Virtual and Augmented Reality (VR/AR) applications. Taking the electrical experiments of technological university as examples, the well designed virtual experimental system has the characteristics of lifelike three dimensional (3D) experimental environments, AR interactive interface on mobile devices, intelligent detecting mechanism and cross-platform. We described VEET’?s flexible design and demonstrate its use in teaching where 120 students from three classes conducted electrical experiments with it. The experiments in VEET were presented on desktop, mobile and web browser using low cost common devices (personal computer, android handheld device, Chrome browser). Evaluating the main performance parameters, the well practicability was confirmed.

In this paper, a series of polyimide (PI) films with different monomer mole ratios between PMDA and ODA (0.980: 1, 0.990: 1, 1.000: 1, 1.010: 1 and 1.015: 1) were prepared in order to investigate the effect of molecular weight on optical properties. Inherent viscosity values were taken as a measure of the molecular weight. The fluorescence properties of the PI films have been measured. The fluorescence spectra show that three obvious emission peaks can be observed at 583 nm (1.00 dL/g), 594 nm (1.42 dL/g) and 603 nm (1.57 dL/g) respectively. In addition, emission peaks show red-shift with the increase of molecular weight, which can attribute to the decease of orbital energy caused by conjugated effect.

A functional potassium sodium niobate/polyimide (KNN/PI) composite films were prepared in this paper. KNN fillers are well dispersed in the PI matrix without any accumulation through in situ polymerization process. The optical band baps of the hybrid films become smaller with the increase of KNN loading. The optical band baps of the films with 0-20 wt% KNN filler are estimated to be 2.61 eV, 2.57 eV, 2.52 eV, 4.29 eV, 2.35 eV respectively.

A novel polyimide (PI) films with three kinds of monomers was synthesized in this paper. The polyimide unit is derived from Pyromellitic dianhydride (PMDA), 3,3',4,4'-benzophenonetetracarboxylic dianhydride, (BTDA), and 4,4, -diaminodiphenyl ether (ODA). The dielectric properties of the films were measured. The dielectric spectra show that dielectric constant is about 3.7, which is larger than the PI with two kinds of monomers. In addition, the loss tangent and conductivity of the films is quite small, which is important for the practical use of them.

In this paper, we improved the home-made EL experimental set-up, have increased the function of TSC, enable the joint measurement of EL and TSC to measure the trap of shallow and deep. It is significant to study material properties. through the Labview8.6 software programming, the data of temperature and current could be collected, then we can get the curve that the current changes with temperature, it is the TSC curve. Experiment result proved the reliability of laboratory equipment.

The electronic structural and optical properties of Polyimide (PI) are studied by first principle method of density theory. It is shown that molecules orbit contribution of PI is derived from carbon 2p orbital and oxygen 2p orbital, respectively,and the band gap from the energy band structure is much smaller than that of the experimental value. It is also found that the band gap calculated from the absorption edge of absorption spectra is in agreement with the result of the energy band structure. Furthermore, the relationship between the formation of dielectric function peaks and other spectral characteristics is interpreted.

In this paper, ZnO Nano-particles is embedded in polyimide, and physical and chemical properties of polyimide/ZnO composite materials have been studied. It is found that different ZnO content will cause UV absorption edge blue shift, and EL tests show that electricity aging and pre-breakdown have changed. For PI/ZnO(1%) and PI/ZnO(2%) composite materials, Electricity aging is at 1.4Mv/cm and 1.5Mv/cm, Pre-breakdown field is at 1.9Mv/cm and 1.8Mv/cm, respectively. In addition, there are emission peaks at 442.8nm, 514.2nm, 609.4nm in the EL spectrum of the PI/ZnO (1%) films and 538nm, 633.2nm of PI/ZnO(2%) films, which indicates that some defects in this area.

The Electroluminescence (EL) intensity and the spectrum of the of the PET films under different temperatures (77K, 296K, 353K) is tested, it is found that the pre-breakdown field under the low normal and high temperature of PET films is about 3.0MV/cm, 3.2MV/cm, 3.4MV/cm, respectively, and the formation of hot electron is not the main reason that cause aging and breakdown of PET films.

The EL intensity and the spectrum of the PET films were tested under the low temperature by home-made experimental set-up on the conditions of DC high electric fields and irradiated by xenon lamp. The result shows that there are emission peaks at about 350~450nm, 500~600nm and 750nm in the EL spectrum of the PET films. The intensity of light emission increases with the applied electric fields; the pre-breakdown field is about 3.3MV/cm, this threshold value is no significant change which compares with the normal temperature.

This page is about the preparation of inorganic nanoparticle polyimide films by in-situ. Through this kind of doping, that changed the physical and chemical properties of polyimide. Experimental film by infrared, ultraviolet, SEM, electrical breakdown experiments, the surface resistivity, volume resistivity, and electrolum- inescent. The results show that the polyimide/ZnO films preparation by this kind of doping, hybrid inorganic nano-particles can reduce polyimide electrical breakdown field, the surface resistivity, volume resistivity, electroluminescent. It testified by electroluminescent show that the electroluminescent position from 561.8nm to 609.4nm. The redshift phenomenon occurs show that the apparent on polyimide trap turn lighter.

A new microwave imidization method was used to prepare polyimide (PI) film in this paper. FT-IR spectrum and ultraviolet absorption spectrum are measured to study the chemical structure and optical properties of this film. The FT-IR spectrum shows that the characteristic imide groups are observed at the peaks of 727.18 cm-1, 1379.67 cm-1 and 1776.51 cm-1, which confirmed imide formation. The ultraviolet absorption spectrum reveals that optical band gap of the PI is about 2.64 eV.