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Showing papers by "National Institute of Advanced Industrial Science and Technology published in 2016"


Journal ArticleDOI
TL;DR: There are significant roots in general and in particular to the CIRP community – which point towards CPPS, and expectations towards research in and implementation of CPS and CPPS are outlined.
Abstract: One of the most significant advances in the development of computer science, information and communication technologies is represented by the cyber-physical systems (CPS). They are systems of collaborating computational entities which are in intensive connection with the surrounding physical world and its on-going processes, providing and using, at the same time, data-accessing and data-processing services available on the Internet. Cyber-physical production systems (CPPS), relying on the latest, and the foreseeable further developments of computer science, information and communication technologies on one hand, and of manufacturing science and technology, on the other, may lead to the 4th industrial revolution, frequently noted as Industrie 4.0. The paper underlines that there are significant roots in general – and in particular to the CIRP community – which point towards CPPS. Expectations towards research in and implementation of CPS and CPPS are outlined and some case studies are introduced. Related new R&D challenges are highlighted.

1,123 citations


Journal ArticleDOI
TL;DR: A review of the state-of-the-art of this multidisciplinary area and identifying the key research challenges is provided in this paper, where the developments in diagnostics, modeling and further extensions of cross section and reaction rate databases are discussed.
Abstract: Plasma–liquid interactions represent a growing interdisciplinary area of research involving plasma science, fluid dynamics, heat and mass transfer, photolysis, multiphase chemistry and aerosol science. This review provides an assessment of the state-of-the-art of this multidisciplinary area and identifies the key research challenges. The developments in diagnostics, modeling and further extensions of cross section and reaction rate databases that are necessary to address these challenges are discussed. The review focusses on non-equilibrium plasmas.

1,078 citations


Journal ArticleDOI
TL;DR: In this paper, a metal-organic framework (MOF)-based separator was proposed to mitigate the shuttling problem in lithium-sulfur batteries, which selectively sieves Li+ ions while efficiently suppressing undesired polysulfides migrating to the anode side.
Abstract: Lithium–sulfur batteries are a promising energy-storage technology due to their relatively low cost and high theoretical energy density. However, one of their major technical problems is the shuttling of soluble polysulfides between electrodes, resulting in rapid capacity fading. Here, we present a metal–organic framework (MOF)-based battery separator to mitigate the shuttling problem. We show that the MOF-based separator acts as an ionic sieve in lithium–sulfur batteries, which selectively sieves Li+ ions while efficiently suppressing undesired polysulfides migrating to the anode side. When a sulfur-containing mesoporous carbon material (approximately 70 wt% sulfur content) is used as a cathode composite without elaborate synthesis or surface modification, a lithium–sulfur battery with a MOF-based separator exhibits a low capacity decay rate (0.019% per cycle over 1,500 cycles). Moreover, there is almost no capacity fading after the initial 100 cycles. Our approach demonstrates the potential for MOF-based materials as separators for energy-storage applications. One of the major problems in Li–S batteries is the undesired shuttling of lithium polysulfides between electrodes. Here the authors present a metal–organic framework-based separator to mitigate the shuttle effect, leading to stable long cycles.

971 citations


Journal ArticleDOI
TL;DR: This work presents a self-templated, catalyst-free strategy for the synthesis of one-dimensional carbon nanorods by morphology-preserved thermal transformation of rod-shaped metal-organic frameworks and demonstrates that this synthetic approach can produce functionally useful materials.
Abstract: One- and two-dimensional carbon nanomaterials are attracting considerable attention because of their extraordinary electrical, mechanical and thermal properties, which could lead to a range of important potential applications. Synthetic processes associated with making these materials can be quite complex and also consume large amounts of energy, so a major challenge is to develop simple and efficient methods to produce them. Here, we present a self-templated, catalyst-free strategy for the synthesis of one-dimensional carbon nanorods by morphology-preserved thermal transformation of rod-shaped metal-organic frameworks. The as-synthesized non-hollow (solid) carbon nanorods can be transformed into two- to six-layered graphene nanoribbons through sonochemical treatment followed by chemical activation. The performance of these metal-organic framework-derived carbon nanorods and graphene nanoribbons in supercapacitor electrodes demonstrates that this synthetic approach can produce functionally useful materials. Moreover, this approach is readily scalable and could be used to produce carbon nanorods and graphene nanoribbons on industrial levels.

839 citations


Journal ArticleDOI
Adam M. Session1, Adam M. Session2, Yoshinobu Uno3, Taejoon Kwon4, Taejoon Kwon5, Jarrod Chapman2, Atsushi Toyoda6, Shuji Takahashi7, Akimasa Fukui8, Akira Hikosaka7, Atsushi Suzuki7, Mariko Kondo9, Simon J. van Heeringen10, Ian K. Quigley11, Sven Heinz11, Hajime Ogino12, Haruki Ochi13, Uffe Hellsten2, Jessica B. Lyons1, Oleg Simakov14, Nicholas H. Putnam, Jonathan C. Stites, Yoko Kuroki, Toshiaki Tanaka15, Tatsuo Michiue9, Minoru Watanabe16, Ozren Bogdanovic17, Ryan Lister17, Georgios Georgiou10, Sarita S. Paranjpe10, Ila van Kruijsbergen10, Shengquiang Shu2, Joseph W. Carlson2, Tsutomu Kinoshita18, Yuko Ohta19, Shuuji Mawaribuchi20, Jerry Jenkins2, Jane Grimwood2, Jeremy Schmutz2, Therese Mitros1, Sahar V. Mozaffari21, Yutaka Suzuki9, Yoshikazu Haramoto22, Takamasa S. Yamamoto23, Chiyo Takagi23, Rebecca Heald1, Kelly E. Miller1, Christian D. Haudenschild24, Jacob O. Kitzman25, Takuya Nakayama26, Yumi Izutsu27, Jacques Robert28, Joshua D. Fortriede29, Kevin A. Burns, Vaneet Lotay30, Kamran Karimi30, Yuuri Yasuoka14, Darwin S. Dichmann1, Martin F. Flajnik19, Douglas W. Houston31, Jay Shendure25, Louis DuPasquier32, Peter D. Vize30, Aaron M. Zorn29, Michihiko Ito20, Edward M. Marcotte4, John B. Wallingford4, Yuzuru Ito22, Makoto Asashima22, Naoto Ueno23, Naoto Ueno33, Yoichi Matsuda3, Gert Jan C. Veenstra10, Asao Fujiyama33, Asao Fujiyama34, Asao Fujiyama6, Richard M. Harland1, Masanori Taira9, Daniel S. Rokhsar1, Daniel S. Rokhsar14, Daniel S. Rokhsar2 
20 Oct 2016-Nature
TL;DR: The Xenopus laevis genome is sequenced and it is estimated that the two diploid progenitor species diverged around 34 million years ago and combined to form an allotetraploid around 17–18 Ma, where more than 56% of all genes were retained in two homoeologous copies.
Abstract: To explore the origins and consequences of tetraploidy in the African clawed frog, we sequenced the Xenopus laevis genome and compared it to the related diploid X. tropicalis genome. We characterize the allotetraploid origin of X. laevis by partitioning its genome into two homoeologous subgenomes, marked by distinct families of 'fossil' transposable elements. On the basis of the activity of these elements and the age of hundreds of unitary pseudogenes, we estimate that the two diploid progenitor species diverged around 34 million years ago (Ma) and combined to form an allotetraploid around 17-18 Ma. More than 56% of all genes were retained in two homoeologous copies. Protein function, gene expression, and the amount of conserved flanking sequence all correlate with retention rates. The subgenomes have evolved asymmetrically, with one chromosome set more often preserving the ancestral state and the other experiencing more gene loss, deletion, rearrangement, and reduced gene expression.

761 citations


Journal ArticleDOI
TL;DR: The possibility to change the molecular assembled structures of organic and organometallic materials through mechanical stimulation is emerging as a general and powerful concept for the design of functional materials, enabling the development of molecular materials with mechanoresponsive luminescence characteristics.
Abstract: The possibility to change the molecular assembled structures of organic and organometallic materials through mechanical stimulation is emerging as a general and powerful concept for the design of functional materials. In particular, the photophysical properties such as photoluminescence color, quantum yield, and emission lifetime of organic and organometallic fluorophores can significantly depend on the molecular packing, enabling the development of molecular materials with mechanoresponsive luminescence characteristics. Indeed, an increasing number of studies have shown in recent years that mechanical force can be utilized to change the molecular arrangement, and thereby the optical response, of luminescent molecular assemblies of π-conjugated organic or organometallic molecules. Here, the development of such mechanoresponsive luminescent (MRL) molecular assemblies consisting of organic or organometallic molecules is reviewed and emerging trends in this research field are summarized. After a brief introduction of mechanoresponsive luminescence observed in molecular assemblies, the concept of "luminescent molecular domino" is introduced, before molecular materials that show turn-on/off of photoluminescence in response to mechanical stimulation are reviewed. Mechanically stimulated multicolor changes and water-soluble MRL materials are also highlighted and approaches that combine the concept of MRL molecular assemblies with other materials types are presented in the last part of this progress report.

664 citations




Journal ArticleDOI
TL;DR: To the best of the authors' knowledge, this work represents the first combination of the photothermal effects of metal nanocrystals with the favorable properties of MOFs for efficient and selective catalysis.
Abstract: Composite nanomaterials usually possess synergetic properties resulting from the respective components and can be used for a wide range of applications. In this work, a Pd nanocubes@ZIF-8 composite material has been rationally fabricated by encapsulation of the Pd nanocubes in ZIF-8, a common metal-organic framework (MOF). This composite was used for the efficient and selective catalytic hydrogenation of olefins at room temperature under 1 atm H2 and light irradiation, and benefits from plasmonic photothermal effects of the Pd nanocube cores while the ZIF-8 shell plays multiple roles; it accelerates the reaction by H2 enrichment, acts as a "molecular sieve" for olefins with specific sizes, and stabilizes the Pd cores. Remarkably, the catalytic efficiency of a reaction under 60 mW cm(-2) full-spectrum or 100 mW cm(-2) visible-light irradiation at room temperature turned out to be comparable to that of a process driven by heating at 50 °C. Furthermore, the catalyst remained stable and could be easily recycled. To the best of our knowledge, this work represents the first combination of the photothermal effects of metal nanocrystals with the favorable properties of MOFs for efficient and selective catalysis.

410 citations


Journal ArticleDOI
TL;DR: Honeycomb-like porous carbon nanostructures are rationally constructed from a metal-organic framework composite that significantly enhances the electrocatalytic performance by increasing the accessible active sites and enhancing mass transport of the gas and electrolyte.
Abstract: Honeycomb-like porous carbon nanostructures are rationally constructed from a metal-organic framework composite. The unique architecture with uniformly distributed high-density active sites significantly enhances the electrocatalytic performance by increasing the accessible active sites and enhancing mass transport of the gas and electrolyte, rendering the resulting catalyst adequate in reaching the desired catalytic performance afforded by Pt for the oxygen reduction reaction.

392 citations


Journal ArticleDOI
22 Jan 2016-Science
TL;DR: A three-dimensional covalent organic framework constructed from helical organic threads, designed to be mutually weaving at regular intervals, has been synthesized by imine condensation reactions of aldehyde functionalized copper(I)-bisphenanthroline tetrafluoroborate, Cu(PDB)2(BF4), and benzidine (BZ).
Abstract: A three-dimensional covalent organic framework (COF-505) constructed from helical organic threads, designed to be mutually weaving at regular intervals, has been synthesized by imine condensation reactions of aldehyde functionalized copper(I)-bisphenanthroline tetrafluoroborate, Cu(PDB)2(BF4), and benzidine (BZ). The copper centers are topologically independent of the weaving within the COF structure and serve as templates for bringing the threads into a woven pattern rather than the more commonly observed parallel arrangement. The copper(I) ions can be reversibly removed and added without loss of the COF structure, for which a tenfold increase in elasticity accompanies its demetalation. The threads in COF-505 have many degrees of freedom for enormous deviations to take place between them, throughout the material, without undoing the weaving of the overall structure.

Journal ArticleDOI
TL;DR: This study provides an organic nanoparticle based strategy that eliminates the need for genetic transfection to remotely regulate cellular machinery and can specifically and rapidly activate the intracellular Ca(2+) influx of neuronal cells in a reversible and safe manner.
Abstract: Optogenetics provides powerful means for precise control of neuronal activity; however, the requirement of transgenesis and the incapability to extend the neuron excitation window into the deep-tissue-penetrating near-infrared (NIR) region partially limit its application. We herein report a potential alternative approach to optogenetics using semiconducting polymer nanobioconjugates (SPNsbc) as the photothermal nanomodulator to control the thermosensitive ion channels in neurons. SPNsbc are designed to efficiently absorb the NIR light at 808 nm and have a photothermal conversion efficiency higher than that of gold nanorods. By virtue of the fast heating capability in conjunction with the precise targeting to the thermosensitive ion channel, SPNsbc can specifically and rapidly activate the intracellular Ca2+ influx of neuronal cells in a reversible and safe manner. Our study provides an organic nanoparticle based strategy that eliminates the need for genetic transfection to remotely regulate cellular machi...

Journal ArticleDOI
TL;DR: In this paper, the authors provide an intensive understanding of aprotic Li-O2 batteries and offer an important guideline for developing reversible and high-efficiency Li−O2 battery.
Abstract: Rechargeable aprotic Li–O2 batteries are one of the most promising next-generation battery technologies that can deliver extremely high energy density. In the past decades, this technology has attracted worldwide attention, and considerable progress has been achieved. However, numerous critical scientific challenges remain to be solved for practical applications. A specific discussion of recent progress from the perspective of the stable aprotic Li–O2 system with high energy efficiency is presented. The discussion is highlighted on the reaction mechanisms on air cathode, stability of cell components in semi-open surroundings, and improvement of battery performance by catalyst design. Challenges and perspectives are also presented. This study provides an intensive understanding of aprotic Li–O2 batteries and offers an important guideline for developing reversible and high-efficiency Li–O2 batteries.

Journal ArticleDOI
TL;DR: The results establish a route for the bulk production of exceptionally long and stable chains composed of more than 6,000 carbon atoms, representing an elegant forerunner towards the final goal of carbyne's bulk production.
Abstract: Strong chemical activity and extreme instability in ambient conditions characterize carbyne, an infinite sp1 hybridized carbon chain. As a result, much less has been explored about carbyne as compared to other carbon allotropes such as fullerenes, nanotubes and graphene. Although end-capping groups can be used to stabilize carbon chains, length limitations are still a barrier for production, and even more so for application. We report a method for the bulk production of long acetylenic linear carbon chains protected by thin double-walled carbon nanotubes. The synthesis of very long arrangements is confirmed by a combination of transmission electron microscopy, X-ray diffraction and (near-field) resonance Raman spectroscopy. Our results establish a route for the bulk production of exceptionally long and stable chains composed of more than 6,000 carbon atoms, representing an elegant forerunner towards the final goal of carbyne’s bulk production. One-dimensional linear carbon chains reaching a length close to 800 nm have been synthesized at high temperature and high vacuum using double-walled carbon nanotubes as nanoreactors.

Journal ArticleDOI
11 Aug 2016-Chem
TL;DR: In this paper, a review summarizes recent progress in the field of immobilized ultrafine metal nanoparticles by focusing on their preparation and catalytic applications, and summarizes the synergistic effects between the UMNPs and the supports.

Journal ArticleDOI
TL;DR: In this paper, a new concept of symmetric Na-ion cells employing layered Na/Ti-containing oxides as bipolar electrodes is proposed and realized, based on the bi-functional roles of titanium.
Abstract: Recently, the attention to sodium-ion batteries has been refocused on large-scale energy storage applications, due to sodium's low cost and infinite abundance. Sodium is one of the most abundant elements on earth and exhibits chemical properties similar to lithium. Owing to their superior sodium storage capability especially for excellent safety and stability, Ti-based compounds have been extensively investigated as both cathode and anode materials. Herein we outline the current cathodes and anodes, and emphasize the critical roles of titanium in developing advanced electrodes for sodium-ion batteries. The latest advances and progress in the exploration of Ti-based compounds with various different frameworks such as NASICON, tunnel, MXenes, spinel, and layered structures are systematically reviewed. The straightforward linking of the structure–function–property relationship for Ti-based compounds, especially for layered Na/Ti-containing oxides, is summarized and analyzed. The titanium element plays a critical role in both positive and negative electrodes, i.e., supplying the charge transfer and high safety for anodes and greatly enhancing the structural and cycling stability for cathodes. Based on the bi-functional roles of titanium, a new concept of symmetric Na-ion cells employing layered Na/Ti-containing oxides as bipolar electrodes is proposed and realized. Symmetric Na-ion cells already offered a high voltage and withstood long time charge–discharge processes, demonstrating the practicality beyond the proof of concept. The participation of titanium in sodium-based electrode materials will greatly promote the development of room-temperature sodium-ion batteries towards stationary energy storage.

Journal ArticleDOI
TL;DR: In this paper, the authors summarize new progress in the development of metal nanoparticle (NP) catalysts, which are categorized into monometallic and heterometallic catalysts with excellent activity and high recyclability for different AB dehydrogenation pathways.
Abstract: Ammonia borane (AB), having a high hydrogen density of 19.6 wt %, has attracted much attention as a promising chemical hydrogen storage material. In the past few years, a number of highly active metal nanoparticle (NP) catalysts, which are easy to handle and separate, have been developed for AB dehydrogenation. In this Perspective, we summarize new progress in the development of metal NP catalysts, which are categorized into monometallic and heterometallic catalysts, with excellent activity and high recyclability for different AB dehydrogenation pathways, including solvolysis (hydrolysis and methanolysis) in protic solvents and dehydrocoupling in nonprotic solvents, and we survey the corresponding methods for the regeneration of AB. Moreover, the merits and drawbacks of solvolysis and dehydrocoupling are discussed.

Journal ArticleDOI
TL;DR: Exosomes are a novel factor of MSC paracrine signaling with an important role in the tissue repair process and suggest that exosomes in CM facilitate the acceleration of fracture healing.
Abstract: Acknowledgements Paracrine signaling by bone-marrow-derived mesenchymal stem cells (MSCs) plays a major role in tissue repair. Although the production of regulatory cytokines by MSC transplantation is a critical modulator of tissue regeneration, we focused on exosomes, which are extracellular vesicles that contain proteins and nucleic acids, as a novel additional modulator of cell-to-cell communication and tissue regeneration. To address this, we used radiologic imaging, histological examination, and immunohistochemical analysis to evaluate the role of exosomes isolated from MSC-conditioned medium (CM) in the healing process in a femur fracture model of CD9−/− mice, a strain that is known to produce reduced levels of exosomes. We found that the bone union rate in CD9−/− mice was significantly lower than wild-type mice because of the retardation of callus formation. The retardation of fracture healing in CD9−/− mice was rescued by the injection of exosomes, but this was not the case after the injection of exosomes-free conditioned medium (CM-Exo). The levels of the bone repair-related cytokines, monocyte chemotactic protein-1 (MCP-1), MCP-3, and stromal cell-derived factor-1 in exosomes were low compared with levels in CM and CM-Exo, suggesting that bone repair may be in part mediated by other exosome components, such as microRNAs. These results suggest that exosomes in CM facilitate the acceleration of fracture healing, and we conclude that exosomes are a novel factor of MSC paracrine signaling with an important role in the tissue repair process. This work focuses on exosomes, which are extracellular vesicles, as a novel additional modulator of cell-to-cell communication. This study evaluated the role of exosomes isolated from mesenchymal stem cell (MSC)-conditioned medium (MSC-CM) in the fracture-healing process of CD9−/− mice, a strain that is known to produce reduced levels of exosomes. Retardation of fracture healing in CD9−/− mice was rescued by the injection of MSC exosomes, but this was not the case after the injection of exosome-free CM. This study finds that MSC exosomes are a novel factor of MSC paracrine signaling, with an important role in the tissue repair process.

Posted Content
TL;DR: A Convolutional Neural Network (CNN)-based model "RotationNet," which takes multi-view images of an object as input and jointly estimates its pose and object category, and achieves the state-of-the-art performance on an object pose estimation dataset.
Abstract: We propose a Convolutional Neural Network (CNN)-based model "RotationNet," which takes multi-view images of an object as input and jointly estimates its pose and object category. Unlike previous approaches that use known viewpoint labels for training, our method treats the viewpoint labels as latent variables, which are learned in an unsupervised manner during the training using an unaligned object dataset. RotationNet is designed to use only a partial set of multi-view images for inference, and this property makes it useful in practical scenarios where only partial views are available. Moreover, our pose alignment strategy enables one to obtain view-specific feature representations shared across classes, which is important to maintain high accuracy in both object categorization and pose estimation. Effectiveness of RotationNet is demonstrated by its superior performance to the state-of-the-art methods of 3D object classification on 10- and 40-class ModelNet datasets. We also show that RotationNet, even trained without known poses, achieves the state-of-the-art performance on an object pose estimation dataset. The code is available on this https URL


Journal ArticleDOI
TL;DR: In this paper, the authors demonstrate the use of high performance nanostructured PbTe-based materials in high conversion efficiency thermoelectric modules and demonstrate the maximum conversion efficiency of ∼8.8% for a temperature difference (ΔT) of 570 K and ∼11% for an ΔT of 590 K.
Abstract: In this work, we demonstrate the use of high performance nanostructured PbTe-based materials in high conversion efficiency thermoelectric modules. We fabricated the samples of PbTe–2% MgTe doped with 4% Na and PbTe doped with 0.2% PbI2 with high thermoelectric figure of merit (ZT) and sintered them with Co–Fe diffusion barriers for use as p- and n-type thermoelectric legs, respectively. Transmission electron microscopy of the PbTe legs reveals two shapes of nanostructures, disk-like and spherical. The reduction in lattice thermal conductivity through nanostructuring gives a ZT of ∼1.8 at 810 K for p-type PbTe and ∼1.4 at 750 K for n-type PbTe. Nanostructured PbTe-based module and segmented-leg module using Bi2Te3 and nanostructured PbTe were fabricated and tested with hot-side temperatures up to 873 K in a vacuum. The maximum conversion efficiency of ∼8.8% for a temperature difference (ΔT) of 570 K and ∼11% for a ΔT of 590 K have been demonstrated in the nanostructured PbTe-based module and segmented Bi2Te3/nanostructured PbTe module, respectively. Three-dimensional finite-element simulations predict that the maximum conversion efficiency of the nanostructured PbTe-based module and segmented Bi2Te3/nanostructured PbTe module reaches 12.2% for a ΔT of 570 K and 15.6% for a ΔT of 590 K respectively, which could be achieved if the electrical and thermal contact between the nanostructured PbTe legs and Cu interconnecting electrodes is further improved.

Journal ArticleDOI
TL;DR: This work used HomFam, ContTest and OXFam to evaluate several methods enabled in MAFFT and found that methods 3 and 4 increased the benchmark scores more consistently than method 2 for the three datasets, suggesting that they are safer to use.
Abstract: Motivation: Large multiple sequence alignments (MSAs), consisting of thousands of sequences, are becoming more and more common, due to advances in sequencing technologies. The MAFFT MSA program has several options for building large MSAs, but their performances have not been sufficiently assessed yet, because realistic benchmarking of large MSAs has been difficult. Recently, such assessments have been made possible through the HomFam and ContTest benchmark protein datasets. Along with the development of these datasets, an interesting theory was proposed: chained guide trees increase the accuracy of MSAs of structurally conserved regions. This theory challenges the basis of progressive alignment methods and needs to be examined by being compared with other known methods including computationally intensive ones. Results: We used HomFam, ContTest and OXFam (an extended version of OXBench) to evaluate several methods enabled in MAFFT: (1) a progressive method with approximate guide trees, (2) a progressive method with chained guide trees, (3) a combination of an iterative refinement method and a progressive method and (4) a less approximate progressive method that uses a rigorous guide tree and consistency score. Other programs, Clustal Omega and UPP, available for large MSAs, were also included into the comparison. The effect of method 2 (chained guide trees) was positive in ContTest but negative in HomFam and OXFam. Methods 3 and 4 increased the benchmark scores more consistently than method 2 for the three datasets, suggesting that they are safer to use. Availability and Implementation: http://mafft.cbrc.jp/alignment/software/ Contact: pj.ca.u-akaso.cerfi@hotak Supplementary information: Supplementary data are available at Bioinformatics online.

Journal ArticleDOI
TL;DR: In this paper, a systematic study was conducted for the analysis of polymer backbone chemical stability in alkaline media, including poly(arylene ethers, poly(biphenyl alkylene)s, and polystyrene block copolymers.
Abstract: Anion exchange membranes are an important component in alkaline electrochemical energy conversion and storage devices, and their alkaline stability plays a crucial role for the long-term use of these devices. Herein, a systematic study was conducted for the analysis of polymer backbone chemical stability in alkaline media. Nine representative polymer structures including poly(arylene ether)s, poly(biphenyl alkylene)s, and polystyrene block copolymers were investigated for their alkaline stability. Polymers with aryl ether bonds in their repeating unit showed poor chemical stability when treated with KOH and NaOCH3 solutions, whereas polymers without aryl ether bonds [e.g., poly(biphenyl alkylene)s and polystyrene block copolymers] remained stable. Additional NMR studies and density functional theory (DFT) calculations of small molecule model compounds that mimic the chemical structures of poly(arylene ether)s confirmed that electron-withdrawing groups near to the aryl ether bonds in the repeating unit acc...

Journal ArticleDOI
22 Jun 2016
TL;DR: The objectives of truck automation are energy saving and enhanced transportation capacity by platooning, and eventually possible reduction of personnel cost by unmanned operation of following vehicles.
Abstract: Technical studies on automated driving of passenger cars were started in the 1950s, but those on heavy trucks were started in the mid-1990s, and only a few projects have dealt with truck automation, which include “Chauffeur” within the EU project T-TAP from the mid-1990s, truck automation by California PATH from around 2000, “KONVOI” in Germany from 2005, and “Energy ITS” by Japan from 2008. The objectives of truck automation are energy saving and enhanced transportation capacity by platooning, and eventually possible reduction of personnel cost by unmanned operation of following vehicles. The sensing technologies for automated vehicle control are computer vision, radar, lidar, laser scanners, localization by GNSS, and vehicle to vehicle communications. Experiments of platooning of three or four heavy trucks have shown the effectiveness of platooning in achieving energy saving due to short gaps between vehicles.

Journal ArticleDOI
TL;DR: In this paper, a facile method of synthesizing IF-MoS2 hollow structures with a diameter of ∼100 nm was described, which can provide large expandable spaces for volume changes occurring during the cycles.
Abstract: Inorganic fullerene (IF)-like structured materials have attracted considerable attention for electrochemical energy storage and conversion. In this report, we describe a facile method of synthesizing IF-MoS2 hollow structures with a diameter of ∼100 nm by a facile solution-phase reduction process to obtain a hollow MoSx precursor under ambient pressures before subsequent annealing of the material at high temperatures to form IF-MoS2 nanocages. TEM images at different reaction stages reveal the hollow structure spontaneously arising in the novel “close-edge” nanocages under the assistance of an ammonia cation bubble template. When evaluated as an anode material for lithium ion batteries, ex situ characterization indicates that these IF-MoS2 hollow nanocages can provide large expandable spaces for volume changes occurring during the cycles. Such a highly desired structure offers remarkably improved lithium storage performance including high reversible capacity and good cycling behavior and high rate capability.

Journal ArticleDOI
TL;DR: Modification of surface hydrophobicity of Pd/UiO-66, a composite comprising a metal-organic framework and stabilized palladium nanoparticles (NPs), using a simple polydimethylsiloxane (PDMS) coating demonstrated significantly improved catalytic efficiency.
Abstract: Surface wettability of active sites plays a crucial role in the activity and selectivity of catalysts. This report describes modification of surface hydrophobicity of Pd/UiO-66, a composite comprising a metal–organic framework (MOF) and stabilized palladium nanoparticles (NPs), using a simple polydimethylsiloxane (PDMS) coating. The modified catalyst demonstrated significantly improved catalytic efficiency. The approach can be extended to various Pd nanoparticulate catalysts for enhanced activity in reactions involving hydrophobic reactants, as the hydrophobic surface facilitates the enrichment of hydrophobic substrates around the catalytic site. PDMS encapsulation of Pd NPs prevents aggregation of NPs and thus results in superior catalytic recyclability. Additionally, PDMS coating is applicable to a diverse range of catalysts, endowing them with additional selectivity in sieving reactants with different wettability.

Journal ArticleDOI
TL;DR: In this article, a collection of short articles written by experts in thermal spray who were asked to present a snapshot of the current state of their specific field, give their views on current challenges faced by the field and provide some guidance as to the R&D required to meet these challenges.
Abstract: Considerable progress has been made over the last decades in thermal spray technologies, practices and applications. However, like other technologies, they have to continuously evolve to meet new problems and market requirements. This article aims to identify the current challenges limiting the evolution of these technologies and to propose research directions and priorities to meet these challenges. It was prepared on the basis of a collection of short articles written by experts in thermal spray who were asked to present a snapshot of the current state of their specific field, give their views on current challenges faced by the field and provide some guidance as to the R&D required to meet these challenges. The article is divided in three sections that deal with the emerging thermal spray processes, coating properties and function, and biomedical, electronic, aerospace and energy generation applications.

Journal ArticleDOI
TL;DR: The first draft genome sequence of a lithophytic orchid, Dendrobium catenatum, is reported, predicting 28,910 protein-coding genes, and finding evidence of a whole genome duplication shared with Phalaenopsis.
Abstract: Orchids make up about 10% of all seed plant species, have great economical value, and are of specific scientific interest because of their renowned flowers and ecological adaptations. Here, we report the first draft genome sequence of a lithophytic orchid, Dendrobium catenatum. We predict 28,910 protein-coding genes, and find evidence of a whole genome duplication shared with Phalaenopsis. We observed the expansion of many resistance-related genes, suggesting a powerful immune system responsible for adaptation to a wide range of ecological niches. We also discovered extensive duplication of genes involved in glucomannan synthase activities, likely related to the synthesis of medicinal polysaccharides. Expansion of MADS-box gene clades ANR1, StMADS11, and MIKC(*), involved in the regulation of development and growth, suggests that these expansions are associated with the astonishing diversity of plant architecture in the genus Dendrobium. On the contrary, members of the type I MADS box gene family are missing, which might explain the loss of the endospermous seed. The findings reported here will be important for future studies into polysaccharide synthesis, adaptations to diverse environments and flower architecture of Orchidaceae.

Journal ArticleDOI
TL;DR: The findings of the bioassays have demonstrated that ePAHs have the ability to affect the endocrine systems of humans and animals, and standardized assay protocols for pathway-based assessments are considered to be important to overcome these issues.

Journal ArticleDOI
TL;DR: AeA1144 is the first known structure of this type among not only Fe-based superconductors but also other materials, which can be regarded as hybrid phases between AeFe 2As2 (Ae = Ca, Sr) and AFe2As2.
Abstract: Fe-based superconductors have attracted research interest because of their rich structural variety, which is due to their layered crystal structures. Here we report the new-structure-type Fe-based superconductors CaAFe4As4 (A = K, Rb, Cs) and SrAFe4As4 (A = Rb, Cs), which can be regarded as hybrid phases between AeFe2As2 (Ae = Ca, Sr) and AFe2As2. Unlike solid solutions such as (Ba1–xKx)Fe2As2 and (Sr1–xNax)Fe2As2, Ae and A do not occupy crystallographically equivalent sites because of the large differences between their ionic radii. Rather, the Ae and A layers are inserted alternately between the Fe2As2 layers in the c-axis direction in AeAFe4As4 (AeA1144). The ordering of the Ae and A layers causes a change in the space group from I4/mmm to P4/mmm, which is clearly apparent in powder X-ray diffraction patterns. AeA1144 is the first known structure of this type among not only Fe-based superconductors but also other materials. AeA1144 is formed as a line compound, and therefore, each AeA1144 has its own s...