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Michinobu T.,Tokyo Institute of Technology | Li Y.,Tokyo Institute of Technology | Hyakutake T.,Public works research institute
Physical Chemistry Chemical Physics | Year: 2013

The rapid growth of the click chemistry concept enables the production of a wide variety of functional polymers. Among the new generation of click chemistry reactions, the highly efficient addition reactions between electron-rich alkynes and cyano-based acceptors, referred to as alkyne-acceptor click chemistry, have found promising application possibilities as polymeric chemosensors. The donor-acceptor chromophores, formed by this click chemistry reaction, feature intense charge-transfer (CT) bands in the visible region, but they are hardly fluorescent. Importantly, the chromophores possess two different nitrogen atoms, namely the aniline nitrogen and cyano nitrogen. The recognition of some specific metal cations by different nitrogen atoms in the polymers led to different modes of changes in the absorption spectra. For example, the hard acid of Fe3+ ion was recognized by the aniline nitrogen, resulting in a decrease in the CT bands. On the other hand, the soft acid of the Ag + ion was captured by the cyano nitrogen, leading to a bathochromic shift in the CT bands. Some specific anions, such as CN-, F -, and I- ions, were also recognized by a chemodocimetric detection mode, discoloring the original solutions. When the CT bands decreased upon the addition of analytes, the polymers were found to serve as turn-on fluorescent sensors. In this perspective, the detailed detection modes of the new polymeric chemosensors are fully described.© 2013 the Owner Societies.


Jayawardena A.W.,Public works research institute | Xu P.,CAS Academy of Mathematics and Systems Science | Li W.K.,University of Hong Kong
Chaos | Year: 2010

A method of estimating the Kolmogorov-Sinai (KS) entropy, herein referred to as the modified correlation entropy, is presented. The method can be applied to both noise-free and noisy chaotic time series. It has been applied to some clean and noisy data sets and the numerical results show that the modified correlation entropy is closer to the KS entropy of the nonlinear system calculated by the Lyapunov spectrum than the general correlation entropy. Moreover, the modified correlation entropy is more robust to noise than the correlation entropy. © 2010 American Institute of Physics.


Akamatsu F.,Shinshu University | Akamatsu F.,Public works research institute | Toda H.,Shinshu University
Environmental Pollution | Year: 2011

Stable nitrogen isotopic composition (δ15N) of aquatic biota increases with anthropogenic N inputs such as sewage and livestock waste downstream. Increase in δ15N of riparian spiders downstream may reflect the anthropogenic pollution exposure through predation on aquatic insects. A two-source mixing model based on stable carbon isotopic composition showed the greatest dependence on aquatic insects (84%) by horizontal web-building spiders, followed by intermediate (48%) and low (31%) dependence by cursorial and vertical web-building spiders, respectively. The spider body size was negatively correlated with the dietary proportion of aquatic insects and spider δ15N. The aquatic subsidies transported anthropogenic N to smaller riparian spiders downstream. This transport of anthropogenic N was regulated by spider's guild designation and body size. © 2011 Elsevier Ltd. All rights reserved.


Grant
Agency: Cordis | Branch: FP7 | Program: CP | Phase: ENV.2013.6.4-3 | Award Amount: 6.53M | Year: 2014

Coastal floods are one of the most dangerous and harmful natural hazards affecting urban areas adjacent to shorelines. Rapid urbanisation combined with climate change and poor governance means a significant increase in the risk of local surface flooding coinciding with high water levels in rivers and high tide or storm surges from the sea, posing a greater risk of devastation to coastal communities. The threats posed need to be addressed not just in terms of flood prediction and control, but taking into account governance and socio-economic issues. PEARL brings together world leading expertise in both the domain of hydro-engineering and risk reduction and management services to pool knowledge and practical experience in order to develop more sustainable risk management solutions for coastal communities focusing on present and projected extreme hydro-meteorological events. The project will examine 7 case studies from across the EU to develop a holistic risk reduction framework that can identify multi-stressor risk assessment, risk cascading processes and strengthen risk governance by enabling an active role for key actors. The research programme links risk and root cause assessment through enhanced FORIN methodology, event prediction, forecast and warning, development of adaptive structural and non-structural strategies and active stakeholder participation. The project aims to develop novel technologies and methods that can improve the early warning process and its components; it builds a pan-European knowledge base gathering real case studies and demonstrations of best practice across the EU to support capacity development for the delivery of cost-effective risk-reduction plans. Additionally, the project provides an interface to relevant ongoing tsunami work: it plugs into global databases, early warning systems and processes at WMO, and contributes to community building, development of guidelines and communication avenues at the global level through IWA.


The recent development of high-quality boring, which uses foam surfactants, has made it possible to examine the detailed geological constitution and structure of landslide bodies. However, geological information related to landslides has not been obtained appropriately even from undisturbed high-quality drilled cores. Moreover, it has been difficult to distinguish between rocks crushed by landslide movement and the fault breccia in accretionary complexes. We examined the detailed geology of high-quality drilled cores of landslide bodies on the Shimanto Belt and the Chichibu Belt. The fault breccia near the landslide bodies was found to exhibit planar fabrics while the crushed breccias in the landslide bodies showed a random fabric. We discovered that classifying the degree of crushing and inspecting the planar fabrics of rocks are effective in the geological determination of landslide bodies. © 2013 Elsevier B.V.

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