Recent advances and developments in advanced green porous nanomaterial for sustainable energy storage application

Journal of Porous Materials - Compared with traditional battery and super capacitor materials, nanomaterials can significantly improve ion transport and electron conductivity. There are many...     

Selective oxidation of olefins and aromatic alcohols with tert‐butylhydroperoxide catalyzed by polymer‐anchored transition‐metal complexes

Three polymer‐anchored metal complexes (Co, Cu, and Pd) were synthesized and characterized. The catalytic performance of these complexes was tested for the oxidation of olefins and aromatic alcohols. These complexes showed excellent catalytic activity and high selectivity. These complexes selectively gave epoxides and aldehydes from olefins and alcohols, respectively. Individually, the effect of various solvents, oxidants, substrate oxidant molar ratios, temperatures, and catalyst amounts for the oxidation of cyclohexene and benzyl alcohol were studied. Under optimized reaction conditions, 96, 81, and 71% conversions of cyclohexene and 86, 79, and 73% conversions of benzyl alcohol were obtained with Co(II), Cu(II), and Pd(II) catalysts, respectively. The catalytic results reveal that these complexes could be recycled more than five times without much loss in activity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Facile Suzuki coupling over ortho-metalated palladium(II) complex anchored on 2D-hexagonal mesoporous organosilica

Phenyl functionalized 2D-hexagonal mesoporous silica material has been synthesized by cationic/non-ionic mixed surfactant templating route. The phenyl group of this mesoporous material is further functionalized via nitration and then reduction of that nitro group to amino functionality, followed by Schiff base condensation and heterogenization of a palladium(II) complex, yielded an ortho-metalated palladium(II) complex anchored in a ordered mesoporous silica matrix. This supported metal complex acts as an efficient catalyst in the Suzuki cross-coupling reaction and shows high selectivity for the bi-aryl products.     

Matching Trajectories of Anatomical Landmarks Under Viewpoint,Anthropometric and Temporal Transforms

An approach is presented to match imaged trajectories of anatomical landmarks (e.g. hands, shoulders and feet) using semantic correspondences between human bodies. These correspondences are used to provide geometric constraints for matching actions observed from different viewpoints and performed at different rates by actors of differing anthropometric proportions. The fact that the human body has approximate anthropometric proportion allows innovative use of the machinery of epipolar geometry to provide constraints for analyzing actions performed by people of different sizes, while ensuring that changes in viewpoint do not affect matching. In addition, for linear time warps, a novel measure, constructed only from image measurements of the locations of anatomical landmarks across time, is proposed to ensure that similar actions performed at different rates are accurately matched as well. An additional feature of this new measure is that two actions from cameras moving at constant (and possibly different) velocities can also be matched. Finally, we describe how dynamic time warping can be used in conjunction with the proposed measure to match actions in the presence of nonlinear time warps. We demonstrate the versatility of our algorithm in a number of challenging sequences and applications, and report quantitative evaluation of the matching approach presented.     

Chemical formation,characterization and properties of polycarbazole

Polycarbazole (PCz) was synthesized by chemical polymerization of carbazole in acetonitrile medium using ammonium persulfate as oxidant. The selection of solvent, concentration of the monomer, composition of the solvent, polymerization time, temperature, and pH were optimized to obtain better quality and yield of the polycarbazole. The synthesized polycarbazole was characterized by various techniques such as UV–Visible, FTIR, ¹H‐NMR, ¹³C‐NMR, COSY, NOESY, and XRD spectroscopy. The solubility of the polycarbazole was tested in various solvents. The thermodynamic stability of the polycarbazole was examined by DSC and TGA‐DTA analysis. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Human Action Recognition in Videos Using Kinematic Features and Multiple Instance Learning

We propose a set of kinematic features that are derived from the optical flow for human action recognition in videos. The set of kinematic features includes divergence, vorticity, symmetric and antisymmetric flow fields, second and third principal invariants of flow gradient and rate of strain tensor, and third principal invariant of rate of rotation tensor. Each kinematic feature, when computed from the optical flow of a sequence of images, gives rise to a spatiotemporal pattern. It is then assumed that the representative dynamics of the optical flow are captured by these spatiotemporal patterns in the form of dominant kinematic trends or kinematic modes. These kinematic modes are computed by performing Principal Component Analysis (PCA) on the spatiotemporal volumes of the kinematic features. For classification, we propose the use of multiple instance learning (MIL) in which each action video is represented by a bag of kinematic modes. Each video is then embedded into a kinematic-mode-based feature space and the coordinates of the video in that space are used for classification using the nearest neighbor algorithm. The qualitative and quantitative results are reported on the benchmark data sets.     

Nodular structure of isotactic polypropylene crystallizes from the melt

This article highlights the melt crystallization behavior of different grades of isotactic polypropylene (iPP) using a hot‐stage polarizing optical microscopy. iPP samples were heated up at a heating rate of 10°C/min passing the melting temperature and then kept for 3 min at a temperature range of 175–200°C before they cooled rapidly at 40°C/min to crystallize isothermally at a range of 130–145°C. It has been found that the temperature at which the samples were kept has a strong effect on the crystallization mode; for samples heated up and kept at temperatures below 190°C, the crystallization started with thin and long rods or nodules, which grew in the circumferential direction only while their lengths remain unchanged as the time passed. The shape of the nodules can be straight, circular, branched, or entangled, and they can grow parallel to each other or they can be crossed or in a random way. This phenomenon disappeared completely for samples melted and kept at temperatures above 195°C. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011