bluuebunny/crossref_metadata_2025 huggingface dataset:
A study on welding quality for the
automatic vertical-position welding
process based on Mahalanobis Distance
method
Authors: Jin B.-J. , Park M.-H. , Yun T.-J. , Shim J.-Y. , Kang B.-Y. , Kim I.-S.
Published: July 2018

Purpose: The welding quality and reducing production cost could be achieved by
developing the automatic on-line welding quality monitoring system. However, investigation
of welding fault to quantify the welding quality on the horizontal-position welding has
been concentrated. Therefore, MD (Mahalanobis Distance) method on the vertical-position
welding process by analysing the transform arc voltage and welding current gained from the
on-line monitoring system has been applied.
Design/methodology/approach: The transformed welding current and arc voltage data
were taken from the experiment whereby the data number was 2500 data/s. The prediction
of Contact Tip to Work Distance (CTWD) to gain best welding quality using the waveform
variations were then taken from the experimental results. MD was employed to quantify the
welding quality by analysing the transformed arc voltage and welding current. Finally, the
optimal CTWD setting has verified the developed algorithms through additional experiments.
Two kinds of experiments has been carried out by changing welding parameters artificially
to verify the sensitivity and feasibility of WQ (Welding Quality) based on the concepts of MD
and normal distribution.
Findings: The results represented that WQ was fully capable of quantifying and qualifying
the welding faults for automatic vertical-position welding process.
Research limitations/implications: The arc welding process on the vertical-position
compared to a horizontal-position welding is much more difficult because the metal transfer
is influenced by the gravity force. To solve the problem, a new algorithm to monitor and
control the welding fault during the arc welding process has been developed. Furthermore,
optimization of welding parameters for the vertical-position welding process was really
difficult to use the developed algorithms because they are only useful in selecting stored data
and not for evaluating the effect of the variation of welding parameters on the weld ability.
Practical implications: The developed algorithm could be achieved the highest welding
quality at 15mm CTWD setting which the welding quality is 99.50% for the start section and
99.68% at the middle section.
Originality/value: This paper proposed a new algorithm which employed the concepts
of MD (Mahalanobis Distance) and normal distribution to describe a good quality welding.
Słuch osób niewidomych - przegląd badań
Authors: Wiśniewska Milena
Published: July 2018

Niniejszy artykuł stanowi przegląd polskich i zagranicznych publikacji, poświęconych słuchowi osób niewidomych.
Zreferowane zostały badania dotyczące takich zagadnień, jak: ogólne własności słuchu osób niewidomych, predyspozycje muzycz...
Edukacja artystyczna jako budowanie kompetencji odbiorcy. Podejścia metodologiczne badań
Authors: Ferenz Krystyna
Published: July 2018

Edukacja artystyczna jako budowanie kompetencji odbiorcy. Podejścia metodologiczne badań
Mainstream Parties’ Issue Engagement and its Implications for the Performance of Populist Parties
Authors: Dalmus Caroline
Published: July 2018

In addition to other factors, the success of populist parties seems to be influenced by the strategic behavior of their competing opponents. Yet, it has not been clearly determined which form of behavior leads to populist success or failure. In order to gain insight into the effectiveness of strategic engagement with populist issues the present study compares an election campaign resulting in populist success with an election campaign resulting in populist failure. For this purpose, the elections in Great Britain in 2010 (low populist vote result) and 2015 (high populist vote result) were chosen. A content analysis of party statements in press releases (N = 734) and newspaper articles (N = 379) covering eight weeks prior to each Election Day was undertaken. The results suggest that the lack of engagement with a salient issue seems to open up opportunities for a populist party. Additionally, divergence and therefore the presence of conflict turns out to have a positive influence on populist success.
Dimensions of Politics in the Czech Republic
Authors: Hájek Lukáš
Published: July 2018

This article deals with the dimensions of politics in the Czech Republic since the state’s establishment in 1993 until 2017. It utilizes MPs’ votes by roll call in the Chamber of Deputies, which is the polity’s centre of gravity. The analysis suggests that two principal drivers shape Czech politics – an ideological (socio-economic left vs right) dimension and an institutional (government vs opposition) division. Due to the changing forms of the ruling cabinets, the dimensionality oscillates between unidimensional and two-dimensional (with a specific phase of as many as three relevant dimensions between 1998–2002). Periods of right-oriented majority cabinets result in a unidimensional competition composed of a merged ideological dimension and an institutional division. Stages of left-oriented majority cabinets ideologically split the opposition camp and highlight the unique role of the socio-economic dimension separated from the still dominant institutional division. During the rule of both left- and right-oriented minority cabinets, political competition is mainly driven by the ideological cleavage since the conventional institutional patterns diminish.
Blockchain, společenská smlouva digitálního věku?
Authors: Kasl František
Published: July 2018

Příspěvek nabízí stručné pojednání o nalézání legitimity definiční autority skrze teorii společenské smlouvy aplikovaném na prostředí technologie blockchain. Po úvodním shrnutí historického vývoje tohoto zásadního teoretického konceptu je pozornost zaměřena na limity, které mu jsou vystavovány v prostředí kyberprostoru. Následně je zmíněna role definičních autorit a jejich význam v tomto kontextu. Pozornost se pak již přesouvá na technologii blockchain, jakožto možný inovativní legitimační model vhodně kombinující požadavek na implicitní podporu většiny s potřebou výkonu autoritativní moci skrze mechanismus s reálným dosahem na dané prostředí. Po rozboru systému vytváření důvěry, změny definičních norem a organizaci podílu na autoritativním výkonu moci v rámci této platformy je však formulován názor, že tato nová technologie, sice přenáší problém legitimity na novou úroveň, ale v jeho vlastní podstatě jej neřeší.
Motley Crew: Collaboration across an Academic Library to Revive an Orphaned Collection
Authors: Jankowski Amy , Schultz Anne , Soito Laura
Published: July 2018

It can be difficult to find time and motivation to effectively address collection management for materials in specialized areas that fall outside the primary scope of one’s usual responsibilities. The pressure of crowded shelves in the authors’ largest library and the associated difficulties of helping users locate materials led a team of faculty librarians and staff to evaluate and consolidate an “orphaned collection” of books in health and medicine call numbers. The authors describe how a project team established a data-informed evaluation and weeding process that minimized affective decision-making and considered the nuances of collection management between disciplines.
Editorial
Authors: Weber Mary Beth
Published: July 2018

It is the time of year when the winners of the ALCTS annual awards are announced, and I am delighted to announce that the 2018 winners of the Edward Swanson Best of LRTS Award are Deborah M. Henry and Tina M. Neville for their paper, “Repositories at Master’s Institutions: A Census and Analysis” (LRTS volume 61, no. 3, July 2017). The authors studied a population of Carnegie-designated master’s institutions to quantify the existence of digital repositories at those institutions. They also conducted a content analysis of repositories containing some type of faculty content. The authors considered various ways that these collections might be discovered, including open web searching, inclusion in repository directories, and access through an institution’s website. The press release for this award notes “No other study has examined the IR’s of this group of academic institutions, nor so carefully analyzed their faculty, student, and other types of content while also gathering data on their platforms, or comparing discoverability using Google, OpenDOAR, ROAR and institutional websites.” I congratulate Tina and Deborah and am honored to be able to present the award at the 2018 ALA Annual Conference in New Orleans.
FITOSSOCIOLOGIA E ESTRUTURA DE UM FRAGMENTO FLORESTAL DA CAATINGA, CEARÁ, BRASIL
Authors: Lima Braulio Gomes de , Coelho Maria de Fatima Barbosa
Published: June 2018

O nordeste do Brasil tem a maior parte de seu território ocupado por caatinga que é caracterizada por vegetação xerófita com diferentes fitofisionomias e considerada o bioma mais sensível à interferência humana e climática. Esse estudo teve o objetivo de caracterizar a composição florística e estrutura de um fragmento de caatinga localizado na Chapada Moura na Fazenda Elmo Moreno em Iguatú, Ceará. Foram estabelecidas 45 parcelas de 10x20 m e foram medidos todos os indivíduos com diâmetro ao nível do solo > 3 cm e altura > 1 m. Foram observados 2256 indivíduos vivos ha-1 e 165 mortos, representando 36 espécies, 29 gêneros e 13 famílias. A diversidade de espécies foi baixa em relação a outras fitofisionomias com Índice de Shannon de 1,59. Croton sonderianus e Combretum leprosum foram as espécies com maior DoR, DR, F, IVC e IVI seguidas de Pityrocarpa moniliformis. O significativo número de espécies vegetais lenhosas exclusivas e raras demonstra que os trabalhos realizados até o momento ainda não amostraram considerável número de espécies presentes nas diferentes regiões do bioma caatinga. Com 70 anos de conservação, a área ainda se encontra em estágio inicial de sucessão ecológica evidenciada pela baixa riqueza florística e maior ocorrência de espécies do gênero Croton.
Homem após cirurgia mutiladora no sistema geniturinário: contribuições a partir de Heidegger e Orem
Authors: Souza Rafael Carlos Macedo , Salimena Anna Maria Oliveira , Paschoalin Heloisa Campos , Souza Ívis Emília Oliveira
Published: July 2018

Objetivo: desvelar sentidos do homem ao desenvolver autocuidado após cirurgia mutiladora no sistema geniturinário e articular reflexões com a Teoria de Orem. Método: pesquisa de natureza qualitativa com abordagem fenomenológica fundada no pensamento e método de Martin Heidegger. Participaram 13 homens que realizaram procedimento cirúrgico mutilador da próstata, testículo ou pênis em um Hospital Universitário da Zona da Mata Mineira. Os depoimentos, acessados durante os meses de junho e agosto de 2016, foram analisados à luz dos conceitos propostos por Heidegger e da Teoria de Orem. Resultados: significaram a necessidade de se cuidar e tomaram para si a responsabilidade de cuidado consigo. Da análise compreensiva emergiu a Unidade de Significação: entender que é necessário ter cuidado durante o tratamento e fazer acompanhamento. Considerações finais: os homens adquirem uma rotina de autocuidado, após serem lançados na facticidade de enfrentar uma cirurgia mutiladora no sistema geniturinário.
Las ramas de conocimiento en la formación del profesorado de la institución superior
Authors: Rodríguez Pulido Josefa , Artiles-Rodríguez Josué , Guerra Santana Mónica
Published: June 2018

La formación del docente universitario es un tema que preocupa a numerosas universidades, cuyo enfoque metodológico está cambiando desde una concepción tradicional de la enseñanza a una perspectiva más práctica. El objetivo del trabajo fue profundizar en los planes que tienen distintas universidades para formar su profesorado y conocer puntos en común y divergentes. La metodología se centra en el análisis de contenido de los planes de formación de 36 universidades españolas y europeas. Los resultados señalan que la formación del profesorado responde a diferentes perfiles y etapas profesionales del docente universitario. Se discuten las implicaciones para la práctica.
Aprendizaje basado en problemas (ABP) y habilidades de pensamiento crítico ¿una relación vinculante?
Authors: Morales Bueno Patricia
Published: June 2018

La propuesta metodológica Aprendizaje Basado en Problemas (ABP) se ha convertido en una alternativa atractiva para ejecutar los cambios en los modelos educativos de la educación superior, en particular porque su entorno de aprendizaje es propicio para el desarrollo de habilidades de pensamiento de orden superior, como el pensamiento crítico. Sin embargo, este proceso no ocurre de manera espontánea, es necesario tomar en consideración los aspectos del modelo que pueden influir en el nivel de logro cuando se tiene el objetivo de mejorar estas habilidades en la formación universitaria. En este trabajo se analiza los aspectos más importantes de la metodología ABP y de la enseñanza de habilidades de pensamiento crítico, buscando poner en evidencia los aspectos más sensibles que afectan la relación vinculante entre ellos. Se discute el caso de las modalidades híbridas ABP y se muestran algunos resultados de investigación que sustentan la discusión.
Comunicación política en el capitalismo tecnológico
Authors: Eguizábal Maza Raúl
Published: July 2018

Politics has become another part of the Society of the Spectacle. In addition, politicians, with their public behaviour and their declarations, contribute to the media spectacle, just as much as celebrities, sports people and pop singers. With the Obama campaign, a new political scenario has come into play, one dominated by new technologies and, most of all, by the Internet that has substituted the previous scenario dominated by television and conventional media. In the first part of this essay, two fetish terms in this new public space are analysed: “connection” and “transparency”. The second part of the essay is a review of the three basic parts of the political sphere: voters, the political system and leaders. Finally, details are given of the main characteristics of the current political leaders.
Estudio de la usabilidad web en marcas de moda españolas mediante la herramienta de análisis heurístico Sirius
Authors: Rodríguez Iria , de Haro Guillermo , Somalo Ignacio
Published: July 2018

These days it is not easy to find a company which does not have a website as part of its business strategy. The impact of the management of interaction between users and web technology (usability) is of vital importance and can be a starting point to improve brand management or make decisions about electronic commerce. The aim of this study is to carry out an evaluative analysis, without users and using the heuristic-based framework Sirius, on the website usability of the most important Spanish fashion companies. These companies were selected from the Interbrand report and websites belonging to brands such as Zara, Mango and Desigual are studied, analyzing different aspects of web usability.
El olfato como refuerzo experiencial: aproximación cualitativa en el ámbito del marketing turístico
Authors: Villanueva Sánchez Helena , García Montero Eva
Published: July 2018

The tourist industry, which is key to the economic development of a country such as Spain with its service-driven economy, has characteristically been an area in which customer satisfaction has been sought in order to encourage loyalty. The tourism product is fundamentally intangible as in most cases it is based on experiences and sensations. For this reason, the application of the latest techniques in experiential and sensory marketing are key when building loyalty in consumers who it has been proved react based on emotions rather than reasoning. Of all the senses which create experiences and memorable sensations, perhaps our sense of smell is the most important and the one which is least taken into account. The latest research in sensory marketing finds that our sense of smell is responsible for an increased sensory enjoyment and is a great help for our memory. The tourist industry is starting to appeal to this sense with more or less conscious and planned strategies. Qualitative research has been conducted, specifically an exploratory and descriptive study, based on in depth interviews with guest experience managers at 14 hotels in order to analyze the effects caused by using aromas with clients and the perception of the brand. This investigation attempts to shed some light on how the hotel industry is making use of scent marketing in order to fulfil its objectives of competitive differentiation and as a result, customer satisfaction and loyalty.
Bases teóricas para el análisis del proceso orgánico de la narrativa colectiva y del storytelling publicitario
Authors: Tapia López Alicia , Durán Gil-Casares Javier
Published: July 2018

Collective narrative or storytelling in advertising is a new form of narrative in which each fragment gives meaning to the whole story at the same time as conveying brand identity to the consumer. These modern collective stories build a narrative using bases which are similar to those used by our ancestors. This article presents a series of elements which constitute the beginnings of a standard methodology of study in the construction of a collective narrative as a sales communication tool. These distinctive components form a conclusive part of the similarities and differences observed in the processes of collective narrative throughout history and the possible applications of storytelling in advertising. In order to do this, we have revised the history of collective narrative from its most primitive form through to the present day. We have also analyzed the connection with current transmedia storytelling in order to look for similar features which allow us to identify basic patterns, as well as the interest in knowing about developments from the origins of group stories through to storytelling in advertising today. In the second part of the investigation, four examples of collective and transmedia narrative processes were examined: The Button Experiment, Twitch Plays, Pandemic and Decode Jay Z with Bing. As a result, we have defined three common stages in the building process of collective narrative, including storytelling in advertising, and we have generated application models which differentiate group stories for sales purposes from general collective narrative with the intention of building a useful guide for studying these systems from an academic perspective. The results may be presented in a simple form but their usefulness in confirmed and they provide a base on which to continue the investigation.
Comunicación interna, sufrimiento y gestión de personas. Una aportación desde la filosofía
Authors: Gismera Tierno Eduardo , Fernández Fernández José Luis , Labrador Fernández Jesús
Published: July 2018

The present research article tries to answer the question of whether the internal communication processes of companies are concerned with detecting, and if necessary, alleviating people’s suffering. In a second part, it tries to recover part of the thought and writing about human suffering in the History of Philosophy and apply it to the processes of internal communication that organizations give as part of their people management activities.
Division of labor in bacteria
Authors: Dal Co Alma , Brannon Charlotte , Ackermann Martin
Published: June 2018

The emergence of subpopulations that perform distinct metabolic roles has been observed in populations of genetically identical bacteria.
Homologous alignment cloning: a rapid, flexible and highly efficient general molecular cloning method
Authors: Tan Lendl , Strong Emily J. , Woods Kyra , West Nicholas P.
Published: June 2018

Homologous alignment cloning (HAC) is a rapid method of molecular cloning that facilitates low-cost, highly efficient cloning of polymerase chain reaction products into any plasmid vector in approximately 2 min. HAC facilitates insert integration due to a sequence alignment strategy, by way of short, vector-specific homology tails appended to insert during amplification. Simultaneous exposure of single-stranded fragment ends, utilising the 3′→5′ exonuclease activity of T4 DNA polymerase, creates overlapping homologous DNA on each molecule. The exonuclease activity of T4 polymerase is quenched simply by the addition of EDTA and a simple annealing step ensures high yield and high fidelity vector formation. The resultant recombinant plasmids are transformed into standardE. colicloning strains and screened via established methods as necessary. HAC exploits reagents commonly found in molecular research laboratories and achieves efficiencies that exceed conventional cloning methods, including another ligation-independent method we tested. HAC is also suitable for combining multiple fragments in a single reaction, thus extending its flexibility.
Wind relaxation and poleward flow events in the upwelling region off Baja California, Mexico
Authors: Vazquez Heriberto J , Gomez-Valdes Jose
Published: June 2018

Wind relaxation events are commonly observed in eastern boundary upwelling ecosystems. The wind fields over the southern part of the California Current System were separated into upwelling-favorable winds and wind relaxations by using a technique based on complex correlation analysis. Using vessel-mounted Acoustic Doppler Current Profiler and conductivity-temperature-depth observations from 4 consecutive Mexican Investigations of the California Current (IMECOCAL) cruises carried out during 2001–2002, a description of the ocean state associated with these stages of the wind field was elaborated for the northern Baja California (Mexico) upwelling region. Relaxation events occurred during each cruise. A coastal poleward flow event was conspicuous when a relaxation event followed a long upwelling favorable wind event. This pattern was also correlated with a negative or close to zero wind curl at the coast. A coastal equatorial jet and an upper-ocean offshore poleward flow were observed during spring, representing a typical upwelling pattern that is correlated with a large positive wind stress curl near the coast. In winter, a surface poleward flow was inhibited by a strong northwest wind event, which generated a shallow equatorward flow. The circulation patterns described here are consistent with theories that explain surface poleward flows through wind relaxation and negative wind curl.
Key words: winds, upwelling regions, poleward flows, wind relaxation events, IMECOCAL.
A stable association with PME‐1 may be dispensable for PP2A demethylation – implications for the detection of PP2A methylation and immunoprecipitation
Authors: Yabe Ryotaro , Tsuji Shunya , Mochida Satoru , Ikehara Tsuyoshi , Usui Tatsuya , Ohama Takashi , Sato Koichi
Published: June 2018

Reversible methyl‐esterification (methylation) of Leu309 in the protein phosphatase 2A catalytic subunit (PP2Ac) is essential for proper biogenesis of the PP2A holoenzyme. Accumulating evidence links PP2Ac methylation to diseases, including cancer and neurodegenerative disorders. Protein phosphatase methyl‐esterase (PME‐1) specifically catalyzes PP2Ac demethylation. We demonstrate that PP2Ac is demethylated in cell extracts even at 0 °C unless prevented by a PME‐1 methyl‐esterase inhibitor. This promotes dissociation of PP2A heterotrimers with B55 or PR72 subunits, but not those with B56 subunits. These results reveal differential sensitivity of ABC heterotrimers to methylation status of the C subunit. Our study advocates caution when interpreting earlier findings, offers an effective protocol for preserving PP2A complexes, and reveals key distinctions between B subunits and their interactions with the AC core dimer of PP2A.
A Transferrin Triggered Pathway for Highly Targeted Delivery of Graphene‐Based Nanodrugs to Treat Choroidal Melanoma
Authors: Zhao Bingxin , Dong Kalun , Lin Mimi , Dong Gongxian , Shan Suyan , Lawson Tom , Yan Lu , Zhang Wenjing , Shi Bingyang , Chou Shulei , Baker Mark S. , Liu Yong
Published: June 2018

The synthesis of transferrin (Tf)‐modified pegylated graphene (PG) and its application as a highly efficient drug delivery carrier for therapy of Ocular Choroidal Melanoma‐1 (OCM‐1) cells is presented. For the first reported time, nanoscaled PG is prepared using an environmentally friendly ball‐milling technique. The unique 2D nanostructure obtained using this PG synthesis approach offers considerable advantages in terms of drug loading and delivery, as well as the conjugation of Tf to PG providing a more targeted delivery vehicle. A highly efficient targeted pathway toward OCM‐1 cells triggered by an affinity between Tf and Tf receptors expressed on the surface of OCM‐1 cells is reported first here. PG‐Tf is observed to easily anchor anticancer drugs such as doxorubicin via π–π stacking. This work performs a Transwell two cells coculture experiment, a 3D in vitro tumor model, and an in vivo mouse model with OCM‐1 tumors to demonstrate the composite's therapeutic superiority over conventional systems for the targeted delivery and controlled release of antitumor drugs.
One Step Process for Infiltration of Magnetic Nanoparticles into CNT Arrays for Enhanced Field Emission
Authors: Sridhar Srividya , Tiwary Chandra Sekhar , Sirota Benjamin , Ozden Sehmus , Kalaga Kaushik , Choi Wongbong , Vajtai Robert , Kordas Krisztian , Ajayan Pulickel M.
Published: June 2018

The complexities and functionalities of carbon nanotube (CNT) architectures can be enhanced even further by the addition of nanoparticles of different kinds. Here, a simple and easily scalable energy efficient infiltration technique is demonstrated to incorporate iron oxide (Fe3O4) particles into aligned forests of CNTs grown by chemical vapor deposition. Scanning electron microscopy and in situ confocal microscopy confirm the presence of Fe3O4 and also explain the mechanism of infiltration and entrapment in the nanotube films. The obtained hybrid films are demonstrated to be excellent field emitters. The infiltration of nanoparticle results in an order of magnitude improvement in the turn‐on field, which can be attributed to several advantageous factors such as reduced screening effects, improved conductivity, and local electric field enhancement in the proximity of the particles. The present method is generic and thus can be applied to other magnetic particles and porous host materials aiming at innovative sensor, electrical and environmental applications.
Boolean and Sequential Logic in a One‐Memristor‐One‐Resistor (1M1R) Structure for In‐Memory Computing
Authors: Zhou Ya‐Xiong , Li Yi , Duan Nian , Wang Zhuo‐Rui , Lu Ke , Jin Miao‐Miao , Cheng Long , Hu Si‐Yu , Chang Ting‐Chang , Sun Hua‐Jun , Xue Kan‐Hao , Miao Xiang‐Shui
Published: June 2018

Memristive devices acting as high‐performance in‐memory computing fabrics have attracted much attention for nonvolatile parallel architectures to break the von Neumann bottleneck. Here, for the first time, a nonvolatile digital logic system with three‐terminal Pt/SiO2/Pt/Ag/GeTe/Ta one‐memristor‐one‐resistor (1M1R) structure is presented. Programmable nonvolatile Boolean logic gates and clocked sequential logic blocks including D latch and D flip‐flop are experimentally implemented, based on which a 4‐bit linear‐feedback shift register with timing design is functionally verified in simulation. With information generation, processing, transmission, and storage performing within the same 1M1R‐based logic blocks, these results consolidate the feasibility of building memristive digital computing system for future non‐von Neumann computing.
Enhanced Charge Transport and Stability Conferred by Iron(III)‐Coordination in a Conjugated Polymer Thin‐Film Transistors
Authors: Wu Hung‐Chin , Rondeau‐Gagné Simon , Chiu Yu‐Cheng , Lissel Franziska , To John W. F. , Tsao Yuchi , Oh Jin Young , Tang Bohan , Chen Wen‐Chang , Tok Jeffery B.‐H. , Bao Zhenan
Published: June 2018

A high performance diketopyrrolopyrrole (DPP)–based semiconducting polymer is modified with ligands to enable metal coordination, and its subsequent effect as field‐effect transistors is investigated. In specific, pyridine‐2,6‐dicarboxamide (PDCA) units are incorporated in a DPP–based polymer backbone with a content from 0 to 30 mol%, and the resulting polymers are then mixed with Fe(II) ions. The coordination and spontaneous oxidation converts Fe(II) to Fe(III) ions to result in Fe(III)‐containing metallopolymers. The resulting metallopolymers are observed to show good solubility in organic solvents and can be easily processed as thin films. The charge transport characteristics are subsequently investigated through the fabrication of field–effect transistor devices, in which an enhanced charge carrier mobility with the Fe(III)‐containing metallopolymers is observed. In specific, an almost twofold improvement in the charge carrier mobility is obtained for the 20% PDCA‐containing polymer after Fe coordination (from 0.96 to 1.84 cm2 V−1 s−1). Furthermore, the operation stability of the metallopolymer‐based devices is found to be significantly improved with low bias stress. Its superior electrical characteristics are attributed to the doping effect of the Fe ions. This study indicates that incorporation of appropriate metallic ions to polymer presents a viable approach to enhance the performance of polymer–based transistor devices.
Fine Tuning Electronic Structure of Catalysts through Atomic Engineering for Enhanced Hydrogen Evolution
Authors: Huang Yichao , Hu Jun , Xu Haoxiang , Bian Wei , Ge Jingxuan , Zang Dejin , Cheng Daojian , Lv Yaokang , Zhang Cheng , Gu Jing , Wei Yongge
Published: June 2018

An efficient, durable, and low‐cost hydrogen evolution reaction (HER) catalyst is an essential requirement for practical hydrogen production. Herein, an effective approach to facilitate the HER kinetics of molybdenum carbide (Mo2C) electrocatalysts is presented by tuning its electronic structure through atomic engineering of nitrogen implantation. Starting from the organoimido‐derivatized polyoxometalate nanoclusters with inherent MoN bonds, the formation of N‐implanted Mo2C (N@Mo2C) nanocrystals with perfectly adjustable amounts of N atoms is demonstrated. The optimized N@Mo2C electrocatalyst exhibits remarkable HER performance and good stability over 20 h in both acid and basic electrolytes. Further density functional theory calculations show that engineering suitable nitrogen atoms into Mo2C can regulate its electronic structure well and decrease MoH strength, leading to a great enhancement of the HER activity. It could be believed that this ligand‐controlled atomic engineering strategy might influence the overall catalyst design strategy for engineering the activation sites of nonprecious metal catalysts for energy conversions.
Fluorophosphates from Solid‐State Synthesis and Electrochemical Ion Exchange: NaVPO4F or Na3V2(PO4)2F3?
Authors: Li Long , Xu Youlong , Sun Xiaofei , Chang Rui , Zhang Yuan , Zhang Xiaona , Li Ju
Published: June 2018

Vanadium‐based fluorophosphates are promising sodium‐ion battery cathode materials. Different phases of NaVPO4F and Na3V2(PO4)2F3 are reported in the literature. However, experiments in this work suggest that there could be confusions about the single‐phase NaVPO4F in solid‐state synthesis. Here, systematic investigation of the mechanism underlying structural and compositional evolution of solid‐state synthesis (NaF:VPO4 = 1:1) is determined by in situ and ex situ X‐ray diffraction and electrochemical measurements. Three reactions—3NaF + 3VPO4 → Na3V2(PO4)2F3 + VPO4 (up to 500 °C), Na3V2(PO4)2F3 + VPO4 → Na3V2(PO4)3 + VF3↑ (600–800 °C), and 2Na3V2(PO4)3 → 2(VO)2P2O7 + Na4P2O7 + amorphous products (above 800 °C)—are validated by in situ XRD and thermogravimetric analysis/differential scanning calorimetry. None of the products reported in this work is consistent with single‐phase NaVPO4F at any temperature. It is speculated that the assignments of I4/mmm and C2/c NaVPO4F from solid‐state synthesis are incorrect, which are instead multiphase mixtures of Le Meins' Na3V2(PO4)2F3, unreacted VPO4, and hexagonal Na3V2(PO4)3. Liquid‐electrolyte‐based electrochemical ion exchange of LiVPO4F produces a tavorite NaVPO4F structure, which is very different from Le Meins' family of Na3Al2(PO4)2F3 polymorphs.
Bandgap Narrowing in Non‐Fullerene Acceptors: Single Atom Substitution Leads to High Optoelectronic Response Beyond 1000 nm
Authors: Lee Jaewon , Ko Seo‐Jin , Seifrid Martin , Lee Hansol , Luginbuhl Benjamin R. , Karki Akchheta , Ford Michael , Rosenthal Katie , Cho Kilwon , Nguyen Thuc‐Quyen , Bazan Guillermo C.
Published: June 2018

Two narrow bandgap non‐fullerene acceptors (NBG‐NFAs), namely, COTIC‐4F and SiOTIC‐4F, are designed and synthesized for the fabrication of efficient near‐infrared organic solar cells (OSCs). The chemical structures of the NBG‐NFAs contain a D′‐D‐D′ electron‐rich internal core based on a cyclopentadithiophene (or dithienosilole) (D) and alkoxythienyl (D′) core, end‐capped with the highly electron‐deficient unit 2‐(5,6‐difluoro‐3‐oxo‐2,3‐dihydro‐1H‐inden‐1‐ylidene)malononitrile (A), ultimately providing a A‐D′‐D‐D′‐A molecular configuration that enhances the intramolecular charge transfer characteristics of the excited states. One can thereby reduce the optical bandgap (Egopt) to as low as ≈1.10 eV, one of the smallest values for NFAs reported to date. In bulk‐heterojunction (BHJ) OSCs, NBG‐NFA blends with the polymer donor PTB7‐Th yield power conversion efficiencies (PCE) of up to 9.0%, which is particularly high when compared against a range of NBG BHJ blends. Most significantly, it is found that, despite the small energy loss (Egopt − eVOC) of 0.52 eV, the PTB7‐Th/NBG‐NFA bulk heterojunction blends can yield short‐circuit current densities of up to 22.8 mA cm−2, suggesting that the design and application of NBG‐NFA materials have substantial potential to further improve the PCE of OSCs.
Superflexible Multifunctional Polyvinylpolydimethylsiloxane‐Based Aerogels as Efficient Absorbents, Thermal Superinsulators, and Strain Sensors
Authors: Zu Guoqing , Kanamori Kazuyoshi , Maeno Ayaka , Kaji Hironori , Nakanishi Kazuki
Published: June 2018

Aerogels are porous materials but show poor mechanical properties and limited functionality, which significantly restrict their practical applications. Preparation of highly bendable and processable aerogels with multifunctionality remains a challenge. Herein we report unprecedented superflexible aerogels based on polyvinylpolydimethylsiloxane (PVPDMS) networks, PVPDMS/polyvinylpolymethylsiloxane (PVPMS) copolymer networks, and PVPDMS/PVPMS/graphene nanocomposites by a facile radical polymerization/hydrolytic polycondensation strategy and ambient pressure drying or freeze drying. The aerogels have a doubly cross‐linked organic–inorganic network structure consisting of flexible polydimethylsiloxanes and hydrocarbon chains with tunable cross‐linking density, tunable pore size and bulk density. They have a high hydrophobicity and superflexibility and combine selective absorption, efficient separation of oil and water, thermal superinsulation, and strain sensing.
Metal–Organic Framework Based Microcapsules
Authors: He Ting , Xu Xiaobin , Ni Bing , Lin Haifeng , Li Chaozhong , Hu Wenping , Wang Xun
Published: June 2018

MOFs are a type of ideal crystalline material with rigid reticular structures whereas microcapsules are usually prepared from soft mater, such as polymers or supramolecules. The synthesis of MOF‐based microcapsules with novel nanostructures at the molecular scale remains a great challenge. Herein, we develop a competitive coordination strategy to synthesize MOF‐based microcapsules with novel bowl‐like structures. During the competitive coordination process, the infinite structures of MOFs are partially broken by the competitive reagents, thus flexibility is introduced into the rigid skeletons and results in the formation of bowl‐like microcapsules. Owing to the unique structure and composition of these nano‐structures, the microcapsules exhibit excellent performance and stability in adsorbing and removing iodine for both vapor and solution. This work describes new opportunities in designing MOF‐based microcapsules with novel structures.
Modular One‐Step Three‐Component Synthesis of Tetrahydroisoquinolines Using a Catellani Strategy
Authors: Qian Guangyin , Bai Miao , Gao Shijun , Chen Han , Zhou Siwei , Cheng Hong‐Gang , Yan Wei , Zhou Qianghui
Published: June 2018

Reported is a modular one‐step three‐component synthesis of tetrahydroisoquinolines using a Catellani strategy. This process exploits aziridines as the alkylating reagents, through palladium/norbornene cooperative catalysis, to enable a Catellani/Heck/aza‐Michael addition cascade. This mild, chemoselective, and scalable protocol has broad substrate scope (43 examples, up to 90 % yield). The most striking feature of this protocol is the excellent regioselectivity and diastereoselectivity observed for 2‐alkyl‐ and 2‐aryl‐substituted aziridines to access 1,3‐cis‐substituted and 1,4‐cis‐substituted tetrahydroisoquinolines, respectively. Moreover, this is a versatile process with high step and atom economy.
Catalytic Enantioselective Synthesis of α‐Chiral Azaheteroaryl Ethylamines by Asymmetric Protonation
Authors: Xu Chao , Muir Calum W. , Leach Andrew G. , Kennedy Alan R. , Watson Allan J. B.
Published: June 2018

The direct enantioselective synthesis of chiral azaheteroaryl ethylamines from vinyl‐substituted N‐heterocycles and anilines is reported. A chiral phosphoric acid (CPA) catalyst promotes dearomatizing aza‐Michael addition to give a prochiral exocyclic aryl enamine, which undergoes asymmetric protonation upon rearomatization. The reaction accommodates a broad range of N‐heterocycles, nucleophiles, and substituents on the prochiral centre, generating the products in high enantioselectivity. DFT studies support a facile nucleophilic addition based on catalyst‐induced LUMO lowering, with site‐selective, rate‐limiting, intramolecular asymmetric proton transfer from the ion‐paired prochiral intermediate.
Embedding 1D Conducting Channels into 3D Isoporous Polymer Films for High‐Performance Humidity Sensing
Authors: Shevate Rahul , Haque Md Azimul , Akhtar Faheem Hassan , Villalobos Luis Francisco , Wu Tom , Peinemann Klaus‐Viktor
Published: June 2018

Isoporous block copolymer (BCP) films have received exponential interest as highly selective membranes, stemming from their unique morphological features, but their applications in functional devices remain to be realized. Now single‐walled carbon nanotubes (CNTs) were efficiently incorporated into isoporous block copolymer films for chemiresistive sensing at room temperature. Leveraging the efficient charge extraction ability of CNTs together with nanochannel arrays aligned perpendicular to the surface of the films, an ultrafast response time of 0.3 s was achieved for humidity detection with a sensor response of about 800 on changing humidity from 10 % to 95 %. Furthermore, the sensor also responds to various organic vapors, underscoring its promising detection capability.
Recognition of Complex Core‐Fucosylated N‐Glycans by a Mini Lectin
Authors: Cabanettes Aurore , Perkams Lukas , Spies Carolina , Unverzagt Carlo , Varrot Annabelle
Published: June 2018

The mini fungal lectin PhoSL was recombinantly produced and characterized. Despite a length of only 40 amino acids, PhoSL exclusively recognizes N‐glycans with α1,6‐linked fucose. Core fucosylation influences the intrinsic properties and bioactivities of mammalian N‐glycoproteins and its level is linked to various cancers. Thus, PhoSL serves as a promising tool for glycoprofiling. Without structural precedence, the crystal structure was solved using the zinc anomalous signal, and revealed an interlaced trimer creating a novel protein fold termed β‐prism III. Three biantennary core‐fucosylated N‐glycan azides of 8 to 12 sugars were cocrystallized with PhoSL. The resulting highly resolved structures gave a detailed view on how the exclusive recognition of α1,6‐fucosylated N‐glycans by such a small protein occurs. This work also provided a protein consensus motif for the observed specificity as well as a glimpse into N‐glycan flexibility upon binding.
Green synthesis of silver nanoparticles using Thymus kotschyanus extract and evaluation of their antioxidant, antibacterial and cytotoxic effects
Authors: Hamelian Mona , Zangeneh Mohammad Mahdi , Amisama Abbas , Varmira Kambiz , Veisi Hojat
Published: June 2018

Present study used ecofriendly, cost efficient and easy method for synthesis of silver nanoparticles (Ag NPs) at the room temperature by Thymus Kotschyanus extract as reducing and capping agent. Various analytical technique including UV–Vis absorption spectroscopy determined presence of Ag NPs in the solution, the functional groups of Thymus Kotschyanus extract in the reduction and capping process of Ag NPs are approved by FT‐IR, crystallinity with the fcc plane approved from the X‐ray diffraction (XRD) pattern, energy dispersive spectroscopy (EDS) determined existence of elements in the sample, surface morphology, diverse shapes and size of present Ag NPs were showed by using scanning electron microscopy (SEM), atomic force microscopy (AFM) and high resolution transmission electron microscopy (HRTEM). Beginning and end destroy temperature of present silver nanoparticles were determined by thermal gravimetric spectroscopy (TGA). In addition, antibacterial, antioxidant and cytotoxicity properties of Ag NPs were studied. Agar disk and agar well diffusion are the methods to determined antibacterial properties of synthesized Ag NPs. Also MIC (Minimum Inhibitory Concentration) and MBC (Minimum Bactericidal Concentration) were recognized by macro broth dilution assay. DPPH free radical scavenging assay was used for antioxidant property and compare to butylated hydroxytoluene (BHT) as standard antioxidant that showed high antioxidant activity more than BHT. Synthesized Ag NPs have great cell viability in a dose depended manner and demonstrate that this method for synthesis silver nanoparticles provided nontoxic. The average diameter of synthesized Ag NPs was about 50–60 nm.
Spinel copper ferrite nanoparticles: Preparation, characterization and catalytic activity
Authors: Amini Mojtaba , Kafshdouzsani Maryam Hosseinpour , Akbari Ali , Gautam Sanjeev , Shim Cheol‐Hwee , Chae Keun Hwa
Published: June 2018

The magnetic CuFe2O4 nanoparticles have been synthesized and characterized by various spectroscopic methods, including X‐ray diffraction (XRD), O K, Cu and Fe K ‐edge X‐ray absorption near edge structure (XANES), energy dispersive X‐ray analysis (EDX), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The azide‐alkyne cycloaddition by the reaction of various phenylacetylenes with a mixture of benzyl halides and NaN3 and also three component (A3) coupling reaction of aldehyde, alkyne and amine catalyzed by CuFe2O4 nanoparticles under aerobic conditions led to the formation of the 1,4‐disubstituted‐1,2,3‐triazoles and propargylamines in excellent yields. The catalyst can be recovered by applying an external magnetic field for the subsequent cycloaddition reactions and reused without any tangible loss in catalytic efficiency.
Hydrothermal leather waste by hydrothermal method for uranium (VI) removal from a Simulated Saline Solution
Authors: Deng Guohong , Zhang Yu , Luo Xuegang , Yang Jiayi
Published: June 2018

Hydrothermal leather waste was prepared by hydrothermal method, using leather waste as the precondition and applying the adsorption of uranium (VI) in solution. The effects of pH value, adsorption time and initial concentration of uranium (VI) on the adsorption efficiency were investigated. The adsorption process was in accordance with the pseudo‐second‐order kinetic model and Freundlich adsorption isotherm model. Kinetic and thermodynamic studies showed that the adsorption process was endothermic and spontaneous, and it reached adsorption equilibrium in 240 min. In the simulated high salinity environment, the adsorbent exhibited excellent adsorption rate on the trace of uranium (VI). The adsorbent was characterized by scanning electron microscopy, flourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy, and it was found that the adsorption mechanism was coordinated complex.
Brummer‐dependent lipid mobilization regulates starvation resistance in Nilaparvata lugens
Authors: Zhou Jinming , Chen Xia , Yan Jing , You Keke , Yuan Zhineng , Zhou Qiang , Lu Kai
Published: June 2018

Energy homeostasis is an essential characteristic of all organisms, requiring fluctuation in energy accumulation, mobilization, and exchange with the external environment. In insects, energy mobilization is under control of the lipase brummer (bmm), which regulates nutritional status by hydrolyzing the ester bonds in triacylglycerol (TAG). In the present study, we investigated the role of bmm in the lipid mobilization and starvation resistance in the brown planthopper (BPH; Nilaparvata lugens), which is economically one of the most important rice pests in Asia. A severe decrease in TAG and glyceride contents was observed in the starved BPHs, while there was a partial rescue after refeeding. The starvation condition caused a significant increase in the expression levels of Nlbmm, and supplement of food after starvation dramatically reduced the Nlbmm expression. Sucrose rescue after starvation significantly suppressed the expression of Nlbmm, while caused an accumulation of TAG and glyceride. Knockdown of Nlbmm by double‐stranded RNA treatment extended the lifespan to starvation, whereas it increased the level of TAG and glyceride in the BPHs. The decreased lipolysis rate by dsNlbmm‐treated BPHs eventually resulted in increase of starvation resistance. These data demonstrated that the regulation of energy homeostasis by Nlbmm affects starvation resistance, probably through lipid mobilization control in N. lugens.