bluuebunny/crossref_metadata_2025 huggingface dataset:
TOF-MRA is reliable to evaluate the degree of MCA obstruction in acute stroke: an inter- and intra- observer study
Authors: Pauline Renou , Thomas Tourdias , Julien Asselineau , Luc Bracoud , Alexandre Vivot , François Rouanet , Jean-Marc Orgogozo , Vincent Dousset , Igor Sibon
Published: March 2014

Introduction: Artery recanalization is one of the best predictors of good clinical outcome after acute ischemic stroke thrombolysis and it could be used as a surrogate marker for outcome if it can be graded reliably. The purpose of this study was to analyze the inter- and intra-observer reliability of the degree of MCA obstruction on TOF-MRA. Methods: 91 patients with a MCA stroke were prospectively included in a multicenter study. They underwent MRI including a TOF-MRA within the first 12 hours after symptoms onset. Two blinded observers quantified the degree of MCA obstruction on TOF-MRA according to a modified TIMI grading system. To assess intra-observer reliability, evaluations by the same investigators were repeated 15 days apart. Dichotomized (TIMI 0-1 versus 2-3) and ordinal TIMI score analyses were performed. Inter- and intra-observer reliability was categorized from poor to excellent based on kappa values. Results: The mean delay between symptom onset and MRI was 6.3 ± 3.3 hours. Analysis of TOF-MRA was impossible in 2.6 % for M1 segment and 6.9% for M2 segment due to technical limitations. The inter- and intra-observer reliability was good to excellent for the dichotomized TIMI score (kappa ranging from 0.77 to 0.91) as well as for the ordinal TIMI score (kappa ranging from 0.82 to 0.96). Conclusion: The substantial reproducibility of the dichotomized and the ordinal TIMI grading system makes the TOF-MRA sequence a reliable tool to evaluate the degree of MCA obstruction and thus recanalization in clinical practice as well as in clinical research.
Asymptotic behavior of solutions of nonlinear neutral delay differential equations
Authors: Wei Gengping
Published: March 2014

This paper is concerned with the nonlinear neutral delay differential equation with positive and negative coefficients $$ [x(t)-c(t)x(t-\tau)]'+p(t)f(x(t-\delta))-q(t)f(x(t-\sigma))=0,\,\ t\geq t_0, $$ where $\tau\in(0,\infty)$, $\delta$ and $\sigma \in[0,\infty)$, $c(t)\in C([t_0,\infty), R)$, $p(t$) and $q(t)\in C([t_0,\infty), [0,\infty))$, $f\in C(R,R)$. Sufficient conditions are obtained under which every solution of the above equation is bounded and tends to a constant as $t\to\infty$. Our results extend and improve some known results.
As emoções dos consumidores da terceira idade no processo de escolha de destinos de viagens
Authors: Esteves Priscila Silva , Slongo Luiz Antonio , Esteves Cristiane Silva , Barcelos Renato Hübner
Published: March 2014

Emotions have great importance in purchasing decisions, however, only recently, researchers started to study them by qualitative approaches. In this context, this study sought to examine them in a still unexplored segment: elderly consumers. For this purpose, this research concentrated in a service for which they have shown a lot of interest – tourism – in order to analyze the emotions present in the choice of travel destinations and their influence on future purchasing decisions. That was done with the use of in-depth interviews aided by the Photo Elicitation Technique (PET). It was then observed that emotions affect the choice for a particular travel destination because the sensations experienced during previous trips are stored in memory and have a strong influence on future decision-making processes. This work also brings interesting contributions for future research because it investigated the occurrence of emotions in 3 separate stages of the consumption process – before, during and after the trip – and not only as just one element in this decision, as normally occurs in most researches about emotions. By demonstrating that this was a favorable decision to better understand the emotions throughout the entire purchase decision process, new paths are opened for further research with different methodological approaches.
Processo de inovação em empresas brasileiras de capital aberto
Authors: Floriani Ricardo , Beuren Ilse Maria , Machado Denise Del Prá Netto
Published: March 2014

This study aims to identify the innovation process used by the open capital Brazilian companies and establish a ranking of the potentially innovative ones. For this, a questionnaire was sent to 484 companies with shares traded in Bovespa, receiving a response from 22. The innovation process is based on the model of Barrett and Sexton (2006). A summary of the results is presented below. (i) Organizational Capabilities – 95.5% answered that they have incentives for innovation activities and 68.2% reported having procedures for all services. The leadership has a facilitator role encouraging the initiative (86.4%) and promotes the maintenance of the group relationship (72.7%). Value risk taking, even through failures and prioritize the learning and experimenting new ideas. (ii) Background of the innovation – reveals aspects of the capacity (internal) or (external). Of the respondents, 59.1% developed internal activities of continuing P D. Training to innovate is present in a continuous or occasional basis in 81.8% of the companies. The respondents characterize the economic environment as dynamic and the majority purchased software and equipments. In only 12 opportunities was a reference to obtaining patents as innovation protection measure. (iii) Focus of innovation – the majority of the companies mentioned process or product innovation. Rewards are offered when the objectives are met and it is brought to attention when this does not occur. (iv) Highlighted performance – the innovations achieved the expectations and created effects. The relevant benefits noticed were: improvement in quality of goods and services, increase of market share, increase of goods and services, and increase of productive capacity.
Informal strategizing in a public organization
Authors: Vieira Marcelo Pedro , Correia Rion Brattig , Lavarda Rosalia Aldraci Barbosa
Published: March 2014

Strategy as Practice analyzes what people do in relation to the development of strategy in organizations, providing insights into current issues in strategy that require a more micro level of understanding (JOHNSON et al., 2007). Considering the perspective of strategy as practice arising from the emerging strategies, we noticed the lack of studies to understand how these activities occur in a daily basis of organization characterizing as informal strategies (WHITTINGTON, 2007). Therefore, this study proposes to address this issue, showing the occurrence of informal strategizing at a public organization under the strategy-as-practice perspective. For this we held a qualitative research through a single case study (EISENHARDT, 1989) in a municipality in southern Brazil. Data were collected through semi-structured interviews with officials of different levels of the organization; direct observation, with notebook guide and analysis of documents provided by the organization, encouraging the triangulation of data. Informal strategies were mainly identified on customer service activities when an applicant’s request is not strictly met under the law or the legislation is dubious and opens room for double-meaning surveying, interpretation and information communication.
Gestão Estratégica de Pessoas, Estratégia de Retenção de Profissionais e Comprometimento Organizacional em uma Estrutura Organizacional Remota
Authors: Leite Nildes Raimunda Pitombo , Albuquerque Lindolfo Galvão de
Published: March 2014

The main objective of this paper is to analyze the characteristics of the strategic people management, the strategy of retention of professional and of obtaining of organizational commitment, by taking up basis the case of Caulim da Amazônia S.A. – CADAM/Pará Pigmentos S.A. – PPSA and seeking to answer the question: what are the characteristics of the strategic management of people, focusing on retention strategy of professional and obtaining of organizational commitment in their peculiarities of remote organizational structure? The research subjects are directors, managers, HR professionals, supervisors and coordinators of units Ipixuna, Monte Dourado and Barcarena, located in northern region of Brazil, for a total of thirty-six respondents. The results show, at the interfaces of the three units, traits that unite people in all these places and around the same purpose: to retain talented professionals. One could say that, it becomes possible to identify the peculiarities that leads to commitment of people with the organizational objectives, these organizational structures, from the strategic approach of people management. The retention of professionals is conditioned on adaptive capacity of these professionals and their families in these regions.
Accelerated Wetland Losses in Coastal Watersheds
Authors: Diffenderfer Robert P.
Published: March 2014

In a study published in late 2013, the US Department of the Interior Fish and Wildlife Service and the National Oceanic and Atmospheric Administration's National Marine Fisheries Service updated and expanded earlier work documenting wetland trends in the coastal watersheds of the Atlantic Ocean, Gulf of Mexico, and Great Lakes. The current study, titled Status and Trends of Wetlands in the Coastal Watersheds of the Conterminous United States 2004‐2009, revisits the same watersheds included in the 2008 study but expands the study to include wetlands in the coastal watersheds along the Pacific Coast.
The dangerous liaison between a discount culture and cost control
Authors: Goetz Melanie K.
Published: March 2014

Could the predictability of fixed billing benefit both the customer and the water utility?
Water utility executive leadership, Part 2: What our CEOs think
Authors: Teodoro Manuel P. , Whisenant Travis E.
Published: March 2014

This article is the second of three that explores the findings of the Water Research Foundation Report, Water Utility Executive Leadership for the 21st Century.
Can We Better Protect Vulnerable Water Supplies?
Authors: Digiano Francis , Grayman Walter M.
Published: March 2014

Recent news stories about industrial spills, fracking, a disturbing lack of data about hazardous chemicals have made the public acutely aware that industrial wastes can indeed accidentally contaminate our surface waters. Such incidents keep water utility officials awake at night worrying about the vulnerability of our water supplies. The effects of industrial spills on drinking water sources are not a new concern to the water industry. A perusal of the Journal over the past half century reveals numerous articles that discuss major industrial spills, regulatory issues associated with spills, treatment options, early warning systems, and other related issues. The article continues with proposed next steps in the process.
California Drought Prompts Water‐Saving Practices
Authors: Seidel Andy
Published: March 2014

In the midst of one of the most severe droughts in centuries, resourceful operators at a North San Diego water reclamation plant manage increasingly precious effluent for community use.
Separation and Recovery of SiC Particles Discharged from Silicon Wafer Production Process
Authors: Shibata Junji , Murayama Norihiro
Published: March 2014

In the slicing process of silicon wafer from silicon single crystal, it has been the general way to cut silicon by wire saws with the lubricant mixture of silicon carbide, as SiC, particles and wrapping oil. After slicing the silicon single crystal, the waste liquor containing SiC and silicon powders is discharged from the process. The particle sizes of SiC and Si are about 10μm and 1μm, respectively and the weight ratio is about 9:1. The particles discharged from slicing waste liquor become the mixture of SiC and SiO2, when the waste liquor is burned after treating the lubricant oil by a filter press. In terms of the minimization of wastes and environment, it is preferable to separate and recover the valuable SiC from SiO2.
In order to solve the problem mentioned above, flotation method can be applied to accomplish the separation of SiC from SiO2. The cationic surfactants of dodecyl-tri-methyl-ammonium chloride (abbreviated as DTMAC hereafter) and tri-methyl-octyl-ammonium chloride (abbreviated as TMOAC hereafter) were used in this study. The adsorption amount of surfactants on SiC and SiO2 particles was measured. The flotation behaviors of SiC and SiO2 were investigated by changing pH, gas flow rate and flotation time in the presence of DTMAC. The purity and yield of SiC were also discussed in the flotation process comprising of roughing, cleaning and scavenging steps. A series of flotation process for SiC gave the purity and yield of 99.7% and 96.7%, respectively.
Ressorts et ressources d’une sociologie de l’expérience urbaine1
Authors: Devisme Laurent
Published: March 2014

La connaissance de l’expérience urbaine, si elle relève principalement d’une microsociologie, comporte des intérêts qui vont bien au-delà, interrogeant notamment la tonalité des espaces publics, les performances des équipements et des dispositifs urbains. Ce texte vise en quelque sorte son exhumation alors que d’une part le contexte académique a eu tendance à segmenter les savoirs urbains et que d’autre part la métropolisation contemporaine a mis à mal la figure (souvent fantasmée) de la ville centrée, délimitée, dense et diverse, expressive.

La première partie du texte revient sur les caractéristiques de la sociologie de l’expérience urbaine ; la deuxième montre l’enjeu de comprendre les équipements qui soutiennent cette expérience à partir des cas du banc public et du belvédère ; la troisième interroge les ressources dont nous pouvons disposer pour comprendre le contexte contemporain de la ville décentrée, sans reprendre les visions homogènes et dépréciatives que les spécialistes tendent souvent à construire à son égard ; enfin, c’est la question du regard sociologique qui est posée et de certaines méthodes que nous pouvons activer pour ne pas délaisser une fonction d’interpellation de la recherche urbaine à l’égard des pratiques de l’aménagement, du design jusqu’au paysage. Si l’enjeu du texte est d’abord théorique, il n’est donc pas sans poser des questions au champ de la production et de la transformation intentionnelles des espaces construits.
La sociologie urbaine à l’épreuve de l’immigration et de l’ethnicité : de Chicago à Montréal en passant par Amsterdam
Authors: Germain Annick
Published: March 2014

L’immigration et la ville sont depuis longtemps indissociables, dans la réalité des flux migratoires comme dans celle de la pensée sociologique. Mais aujourd’hui, les transformations des premiers imposent de nouveaux agendas de recherche à la seconde. On se propose donc de faire une lecture synthétique de ces changements en quatre temps, en commençant par rappeler le débat sur les villes paradigmatiques en Études urbaines et la place centrale qu’y occupe l’immigration. Ensuite, on examinera les nouvelles thématiques que mobilisent les chercheurs en sociologie urbaine en fonction des nouveaux paysages urbains de l’immigration. Ces paysages fortement contrastés selon qu’il s’agit de villes américaines, françaises ou néerlandaises, conditionnent en partie les agendas de recherche. Pour dresser celui de nos métropoles, que nous esquisserons en cinq propositions à partir des recherches sur Montréal, nous situerons les particularités des métropoles canadiennes. La fluidité des territoires de l’immigration invite en effet un recentrage de la sociologie urbaine sur les interactions réciproques à l’échelle de la vie quotidienne et sur les lieux où se négocie l’ethnicité.
Rester ou partir pour s’en sortir : du rôle des soutiens rapprochés dans les expériences résidentielles des jeunes de classes populaires
Authors: Faure-Rouesnel Laurence , Le Dantec Éliane
Published: March 2014

Dans nos sociétés contemporaines, la mobilité est élevée au rang de qualité cardinale et, à l’inverse, l’ancrage renvoie au lexique négatif du manque de dynamisme. Les parcours des jeunes de milieux populaires que nous avons enquêtés par entretiens laissent distinctement entrevoir que la mobilité n’est pas une posture individuelle et sociale plus positive que l’ancrage. Les jeunes mobiles, à la différence des ancrés, sont plutôt en situation de rupture familiale et ne disposant pas de soutiens rapprochés sur lesquels s’appuyer, leurs pratiques de mobilité procèdent bien plus de contraintes que d’un choix construit et anticipé. Inversement, les jeunes de milieux populaires qui ne sont pas mobiles et prolongent la cohabitation au domicile parental sont en situation de pouvoir bénéficier des solidarités familiales qui leur permettent, faute d’accéder à l’indépendance économique et résidentielle par l’entrée dans l’activité professionnelle stable, d’attendre en étant sécurisés matériellement et affectivement. L’article souligne par ailleurs les ambivalences attachées tant aux pratiques de mobilité qu’à l’ancrage territorial.
Ancrage et mobilité de familles d'origine africaine : regards croisés de deux générations
Authors: Aouici Sabrina , Gallou Rémi
Published: March 2014

L'article propose d’étudier l’évolution des relations au sein de familles d'origine subsaharienne vivant en France, à partir de l'interrogation de deux générations adultes (parents et enfants jeunes adultes). La double référence des pays d'attache en matière de pratiques, de valeurs, de normes ou de principes éducatifs est permanente. Enfants et parents apportent leurs regards croisés sur le parcours, l'histoire et le destin de chacun. La construction d’identités individuelles marquées par des références multiples diffère selon la génération d’appartenance. Les parents migrants restent attachés à leur identité africaine (ethnique, nationale, panafricaine, voire transnationale) tout en reconnaissant que leur identité a intégré une « part » française. Les jeunes en revanche déclarent se sentir citoyens français et souhaiteraient être reconnus comme tels. Les deux générations affirment se sentir à l’aise en France. Si les jeunes expriment un intérêt pour l’Afrique, preuve de leur attachement pour les terres d’origine, ils ne sont pas pour autant tentés d’y vivre. Quant aux parents, ils hésitent sur le lieu de leur « dernière demeure », entre reposer dans la terre des ancêtres ou être inhumés en France pour rester proches de la lignée qu’ils y ont fondée. La réflexion s’appuie sur une soixantaine d’entretiens réalisés auprès de parents migrants (socialisés en Afrique) et de leurs enfants (nés ou arrivés jeunes en France).
The Sense of Time in Anglo-Saxon England
Authors: Liuzza R.M.
Published: March 2014

Long before the invention of the mechanical clock, the monastic computes offered
a model of time that was visible, durable, portable and objectifiable. The
development of ‘temporal literacy’ among the Anglo-Saxons involved not only the
measurement of time but also the ways in which the technologies used to measure
and record time — from sundials and church bells to calendars and chronicles —
worked to create and reorder cultural capital, and add new scope and range to
the life of the imagination. Techniques of time measurement are deeply
implicated in historical consciousness and the assertion of identity; this paper
proposes some avenues of exploration for this topic among the Anglo-Saxons.
The Durham Mummy: Deformity and the Concept of Perfection in the Ancient World
Authors: Finch Jacqueline
Published: March 2014

In 1964 radiographs of an Egyptian mummy displayed by the, then, Gulbenkian
Museum of Art and Archaeology in Durham revealed an artificial upper limb
attached to a deformed lower forearm. The limb was removed for further study. It
concluded that the deformity was due to pre-mortem, amputation
above the wrist, the ancient embalmers applying a crude restoration. In 2005 the
author undertook a detailed reappraisal of this restored limb. These findings
now suggest that this individual exhibits a congenital deformity to the upper
limb. Such a proposal prompts a discourse on how deformity was perceived, not
only by ancient Egyptian society but by those across the ancient world. Textual
sources have been selected to highlight how perfection of the physical body was
prized by some cultures, contrasting this with how those who exhibited
‘otherness’,were either accepted or marginalized.
Analysis of printed silver electrode on amorphous indium gallium zinc oxide
Authors: Ueoka Yoshihiro , Nishibayashi Takahiro , Ishikawa Yasuaki , Yamazaki Haruka , Osada Yukihiro , Horita Masahiro , Uraoka Yukiharu
Published: March 2014

Silver (Ag) electrodes printed on amorphous indium gallium zinc oxide (a-InGaZnO) were investigated to analyze their effect on thin-film transistor (TFT) characteristics. The TFT characteristics of samples annealed at 250 °C deteriorated seriously owing to an aggregation of Ag. In addition, the TFT characteristics deteriorated even for 200 °C annealing with oxygen and nitrogen atmospheres. From measurements of secondary ion mass spectrometry and Fourier transform infrared spectroscopy, we found that carbon and hydrogen contained in printed Ag electrodes seriously affect the TFT characteristics. The reduction and protection against these impurities in Ag ink is the key point in the application of printed Ag electrodes to a-InGaZnO TFTs.
Wire diameter dependence in the catalytic decomposition of H2
Authors: Umemoto Hironobu
Published: March 2014

Jansen et al. have demonstrated that the dissociaiton rate of H2 molecules on hot wire surfaces, normalized per unit surface area, depends on the wire diameter based on the electrical power consumption measurements [J. Appl. Phys. 66, 5749 (1989)]. Mathematical modeling calculations have also been presented to support their experimental results. In the present paper, it is shown that such a wire diameter dependence cannot be observed and that the H-atom density normalized by the wire surface area depends little on the wire diameter. Modeling calculations also show that the wire diameter dependence of the dissociation rate cannot be expected under typical decomposition conditions.
Fabrication of ionic liquid ultrathin film by sequential deposition
Authors: Morino Yusuke , Kanai Yuta , Imanishi Akihito , Yokota Yasuyuki , Fukui Ken-ichi
Published: March 2014

A simple, mild, reproducible, and controllable nanodeposition method for ionic liquids (ILs) by ejection of IL solution through a high-speed electromagnetic valve (pulse valve) to a substrate under vacuum is proposed (pulse-valve method). Sequential deposition of an IL [1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (BMIM-TFSI)] on Au(111) substrates from its methanol solution was examined by adopting the pulse-valve method and the deposited IL films were analyzed by X-ray photoelectron spectroscopy (XPS) and tapping-mode atomic force microscopy (AFM). The amount of IL deposited per a pulse was successfully reduced to less than an equivalent thickness of 0.2 nm. The deposited IL was homogeneously distributed over a substrate area of 1 × 1 cm2 substrate area and the deposited amount was reproducible for independent depositions.
Block rotation: Tectonic response of the Sichuan basin to the southeastward growth of the Tibetan Plateau along the Xianshuihe‐Xiaojiang fault
Authors: Wang Erchie , Meng Kai , Su Zhe , Meng Qingren , Chu Jean J. , Chen Zhiliang , Wang Gang , Shi Xuhua. , Liang Xinquan
Published: March 2014

GPS field and seismic data show that the southeastern margin of the Tibetan Plateau is tectonically and seismically active. This activity is due to the southeastward extrusion of the Chuandian fragment, a large crustal block rotating clockwise around the northeastern syntaxis of the Himalayas. The eastern boundary fault of this fragment is defined by the left‐lateral Xianshuihe‐Xiaojiang fault, which abruptly truncates the Sichuan basin of the Yangtze block. Our paper presents evidence indicating that the Sichuan basin experienced right‐lateral shear along its margin, including the Longmen Shan fault belt, as shown by the presence of a large number of interference deformation features, including S‐shaped and Z‐shaped folds and faults, aligned in an en echelon pattern. This study hypothesizes that the Sichuan basin experienced counterclockwise rotation, dragged by the left‐lateral movement along the Xianshuihe fault, and it is this rotation that was the underlying cause of the 12 May 2008 Wenchuan Ms 7.9 earthquake. During the rotation, the Sichuan basin decoupled along a subhorizontal decollement fault zone that developed along Triassic gypsum‐ and coal‐bearing rocks, at a mean depth of ~5000 m, below which the Paleozoic rocks experienced much more intense deformation than the overlying Mesozoic rocks, suggesting that the lower part of the basin experienced a larger‐scale rotation relative to the uppermost part of the basin. Based on thermal data from the western margin of the Sichuan basin and from along the Xianshuihe fault, the counterclockwise bending/rotation of the Sichuan basin initiated in late Cenozoic time (~13 Ma).
A purely structural restoration of the NFP20‐East cross section and potential tectonic overpressure in the Adula nappe (central Alps)
Authors: Pleuger Jan , Podladchikov Yuri Y.
Published: March 2014

Common extrusion‐type models for the high‐ to ultrahigh‐pressure Adula nappe require a major normal fault along the top of this unit which is not conveyed in the structural record. This implies that such a normal fault existed but was completely erased during later deformational stages. However, there is evidence that decompression occurred during top‐to‐the‐foreland thrusting. We performed a new, purely structural kinematic restoration of the central part of the NFP20‐East cross section in order to estimate the burial depths of individual units without converting petrological pressure data into depth under the assumption that pressures were lithostatic. The results show that pressures within most of the units were close to but somewhat higher than lithostatic for several stages of the tectono‐metamorphic history. Only for the maximum burial stage of the Adula nappe, we estimate local tectonic overpressures of 40 to 80% of the lithostatic pressures. Accepting such an amount of overpressure, which is moderate compared to values theoretically possible, the Adula nappe was probably not subducted to subcrustal depth. We propose that the structural record of the Penninic nappe stack is quite complete and suggest that the decay of tectonic overpressure is a feasible explanation for decompression from eclogite‐ to amphibolite‐facies conditions during thrusting. Consequently, exhumation and convergence rates of the Eocene to Oligocene Alps may be smaller than previously assumed.
Silver Triflate‐Catalyzed Cyclization of 2‐Amino‐6‐propargyl‐ amineazines Leading to Iminoimidazoazines
Authors: Chioua Mourad , Samadi Abdelouahid , Soriano Elena , Infantes Lourdes , Marco‐Contelles José
Published: March 2014

We report here that the silver triflate‐catalyzed cyclization of 2‐amino‐6‐propargylamineazines affords new and highly functionalized iminoimidazoazines. We have investigated the scope and limitations of the present methodology, and some aspects of the reactivity of the resulting iminoimidazopyridines have been explored, and a DFT‐based mechanistic analysis of the silver triflate‐catalyzed cyclization has been undertaken.

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Rhodium‐Catalysed Tandem Hydroformylation/Arylation Reaction with Boronic Acids
Authors: Almeida Ana R. , Dias Roberto D. , Monteiro Carlos J. P. , Abreu Artur R. , Gois Pedro M. P. , Bayon J. Carles , Pereira Mariette M.
Published: March 2014

A new efficient multicatalytic process involving a single catalyst to promote tandem hydroformylation/arylation reactions is disclosed. The effect of the rhodium ligand was evaluated and the rhodium/triphenylphosphine catalytic system was selected to apply the methodology to different olefins and boronic acids. High yields (up to 89%) and good to excellent isomer ratios (up to 98:2) were achieved using aryl olefins as starting materials. This new methodology allows the preparation of secondary alcohols, from simple olefins, and paves the way for the synthesis of high‐value products, namely vinylindole and anethole derivatives.

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Tungsten and Molybdenum 2,4,6‐Trimethylbenzylidyne Complexes as Robust Pre‐Catalysts for Alkyne Metathesis
Authors: Haberlag Birte , Freytag Matthias , Jones Peter G. , Tamm Matthias
Published: March 2014

A series of 2,4,6‐trimethylbenzylidyne tungsten and molybdenum complexes was prepared from the tribromides mer‐[MesCMBr3(dme)] (9a, M=W; 9b, M=Mo, dme=1,2‐dimethoxyethane). Successive reaction of complexes 9 with lithium or potassium hexafluoro‐tert‐butoxide and lithium 1,3‐di‐tert‐butylimidazolin‐2‐imide, (Imt‐BuN)Li, afforded the imidazolin‐2‐iminato complexes [MesCM{OC(CF3)2Me}2(Imt‐BuN)] (10a, M=W; 10b, M=Mo), whereas the reactions of 9 with three equivalents of LiOSi(O‐t‐Bu)3 or KOC(CF3)3 gave [MesCM{OSi(O‐t‐Bu)3}3] (11a, M=W; 11b, M=Mo) and [MesCM{OC(CF3)3}3] (12a, M=W; 12b, M=Mo), respectively. For comparison, the benzylidyne complex [PhCMo{OSi(O‐t‐Bu)3}3] (7b) was also prepared, and its molecular structure together with those of 10a, 10b, 11b, 12a and 12b were established by X‐ray diffraction analysis. Complexes 10 and 11 were employed as pre‐catalysts for the alkyne metathesis of the test substrate 3‐pentynyl benzyl ether (13) at low catalyst loadings (1 mol%) in the presence of molecular sieve (5 Å). Comparative studies of these 2,4,6‐trimethylbenzylidyne species (MesCM) with their benzylidyne analogues (PhCM) revealed that the increased steric bulk renders the former more stable and manageable in air in solid form for shorter periods of time, but at the expense of a slower initiation, which requires higher temperatures or longer reaction times.

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Catalytic Asymmetric Alkylation of 3‐Aryl‐Substituted Oxindoles to give 3,3‐Disubstituted Oxindoles under Phase‐Transfer Conditions
Authors: Deng Fei , Moteki Shin A. , Maruoka Keiji
Published: March 2014

An efficient enantioselective method for the construction of all‐carbon quaternary stereocenters from 3‐aryl‐substituted oxindoles via asymmetric phase‐transfer alkylation has been developed. The products are obtained in high yields and optical purity of up to 93 % ee by using (S,S)‐3,4,5‐trifluorophenyl‐NAS bromide as a chiral phase‐transfer catalyst. The 3,3‐disubstituted oxindole products are valuable intermediates for the synthesis of bioactive indole‐containing natural products.
Synthesis of Cyclopropane Spirooxindoles by means of a Vinylogous Organocatalytic Cascade
Authors: César da Silva Rodrigo , Chatterjee Indranil , Escudero‐Adán Eduardo , Weber Paixão Marcio , Melchiorre Paolo
Published: March 2014

The stereoselective construction of spirooxindolic cyclopropane derivatives is achieved by means of a vinylogous cascade reaction that successfully integrates a vinylogous iminium ion/dienamine tandem sequence. The chemistry capitalizes upon a rare example of asymmetric 1,6‐addition to 2,4‐dienals, which proceeds with exclusive δ‐site selectivity.
Rein metallische Lewis‐Paare (MOLPs) durch reversible Insertion von Ruthenium‐ und Osmiumfragmenten in Metall‐Bor‐Doppelbindungen
Authors: Bertsch Stefanie , Bertermann Rüdiger , Braunschweig Holger , Damme Alexander , Dewhurst Rian D. , Phukan Ashwini K. , Saalfrank Christian , Vargas Alfredo , Wennemann Benedikt , Ye Qing
Published: March 2014

Neue rein metallische Lewis‐Paare (Metal‐Only Lewis Pairs, MOLPs; Ru→Cr und Os→Cr) wurden durch Insertion nullwertiger Ruthenium‐ oder Osmiumkomplexe in die Chrom‐Bor‐Doppelbindung von Borylenkomplexen erhalten. Diese Reaktion führt zu neuen Borylenkomplexen (unter anderem zum ersten Osmiumborylenkomplex) und ist kristallisationskontrolliert: Das Auflösen der Komplexe führt zur Rückbildung der Ausgangsverbindungen. Zusätzlich zu quantenchemischen Untersuchungen der ungewöhnlichen MOLPs wird auf Grundlage von DFT‐Rechnungen auch ein Mechanismus für diese Rückreaktion vorgeschlagen.
Gas‐Phase Structure Determination of Dihydroxycarbene, One of the Smallest Stable Singlet Carbenes
Authors: Womack Caroline C. , Crabtree Kyle N. , McCaslin Laura , Martinez Oscar , Field Robert W. , Stanton John F. , McCarthy Michael C.
Published: March 2014

Carbenes are reactive molecules of the form R1C̈R2 that play a role in topics ranging from organic synthesis to gas‐phase oxidation chemistry. We report the first experimental structure determination of dihydroxycarbene (HOC̈OH), one of the smallest stable singlet carbenes, using a combination of microwave rotational spectroscopy and high‐level coupled‐cluster calculations. The semi‐experimental equilibrium structure derived from five isotopic variants of HOC̈OH contains two very short CO single bonds (ca. 1.32 Å). Detection of HOC̈OH in the gas phase firmly establishes that it is stable to isomerization, yet it has been underrepresented in discussions of the CH2O2 chemical system and its atmospherically relevant isomers: formic acid and the Criegee intermediate CH2OO.
Visible‐Light Photochemical Activity of Nanoporous Carbons under Monochromatic Light
Authors: Velasco Leticia F. , Lima Joao C. , Ania Conchi
Published: March 2014

By using monochromatic light the ability of semiconductor‐free nanoporous carbons to convert the low‐energy photons from the visible spectrum into chemical reactions (i.e. phenol photooxidation) is demonstrated. Data shows that the onset wavelength of the photochemical activity can be tuned by surface functionalization, with enhanced visible‐light conversion upon introducing N‐containing groups.
C4 Cumulene and the Corresponding Air‐Stable Radical Cation and Dication
Authors: Li Yan , Mondal Kartik Chandra , Samuel Prinson P. , Zhu Hongping , Orben Claudia M. , Panneerselvam Saravanan , Dittrich Birger , Schwederski Brigitte , Kaim Wolfgang , Mondal Totan , Koley Debasis , Roesky Herbert W.
Published: March 2014

A neutral C4 cumulene 1 that includes a cyclic alkyl(amino) carbene (cAAC), its air‐stable radical cation 1.+, and dication 12+ have been synthesized. The redox property of 1.+ was studied by cyclic voltammetry. EPR and theoretical calculations show that the unpaired electron in 1.+ is mainly delocalized over the central C4 backbone. The commercially available CBr4 is utilized as a source of dicarbon in the cumulene synthesis.
Myths of Political Independence, or How Not to Solve the Corruption Problem: Lessons for Vietnam
Authors: Painter Martin
Published: March 2014

Corruption is widely identified as a critical problem for developing economies and is also viewed as a priority issue by international organisations and donors. Governments such as Vietnam place anti‐corruption high on their policy agenda. However, external observers regularly criticise them for not meeting their targets. The problem with the critique is that it mostly places the blame on implementation failures when the issue is as much a design failure. Templates for anti‐corruption success in fact misread the practical lessons. One element of the standard template, the need for an ‘independent’ anti‐corruption enforcement system, misreads the meaning and empirical reality of ‘independence’. Evidence is presented from Singapore, Hong Kong and Indonesia to show that their anti‐corruption agencies are ‘independent’ more in the sense that they are powerful, rather than in the sense that they are apolitical. The lesson for Vietnam is that misleading design principles such as ‘political independence’ are a distraction from the task of strengthening the anti‐corruption law enforcement system.
One‐Pot Template‐Free Synthesis of NaYF4 Upconversion Hollow Nanospheres for Bioimaging and Drug Delivery
Authors: Tian Gan , Duan Longsheng , Zhang Xiao , Yin Wenyan , Yan Liang , Zhou Liangjun , Liu Xiaodong , Zheng Xiaopeng , Li Jinxia , Gu Zhanjun , Zhao Yuliang
Published: March 2014

Hollow‐structured nanomaterials with fluorescent properties are extremely attractive for image‐guided cancer therapy. In this paper, sub‐100 nm and hydrophilic NaYF4 upconversion (UC) hollow nanospheres (HNSs) with multicolor UC luminescence and drug‐delivery properties were successfully prepared by a facile one‐pot template‐free hydrothermal route using polyetherimide (PEI) polymer as the stabilizing agent. XRD, SEM, TEM, and N2‐adsorption/desorption were used to characterize the as‐obtained products. The growth mechanism of the HNSs has been systematically investigated on the basis of the Ostwald ripening. Under 980 nm excitation, UC emissions of HNSs can be tuned by a simple change of the concentration or combination of various upconverters. As a result, the PEI‐coated HNSs could be used as efficient probes for in vitro upconversion luminescence (UCL) cell imaging. Furthermore, a doxorubicin storage/release behavior and cancer‐cell‐killing ability investigation reveal that the product has the potential to be a drug carrier for cancer therapy.
Trends and variability of monsoon and other rainfall seasons in Western Himalaya, India
Authors: Singh R. B. , Mal Suraj
Published: March 2014

The local hydrological, agricultural and economic activities heavily depend on micro‐level rainfall. Therefore, this study examines trends and variability of rainfall in Uttarakhand state of western Himalaya, India. The season and station‐wise results of this study differ from India level results. The annual rainfall declined in high altitudes. Similarly, the monsoon rains declined in high altitudes and increased in low altitudes, whereas winter rainfall show mixed trends. The variability of monsoon rainfall was lowest for all stations and seasons, while the winters show low variability. Inter‐seasonal variability is recorded highest in plains and lowest in high altitudes.
Die IR‐Spektren von 9‐Cyananthracen und 9, 10‐Dicyananthracen von 220–3100 cm−1
Authors: Bruhn W. , Mecke R. , Witt K.
Published: March 2014

Messungen des Dichroismus von 9‐Cyananthracen und 9, 10‐Dicyananthracen im polarisierten Licht und Vergleich mit der im wesentlichen bekannten Zuordnung des IR‐Schwingungsspektrums von Anthracen ermöglichen eine erste Deutung der IR‐Spektren der beiden Anthracenderivate. Einige Umstellungen in der Zuordnung des IR‐Schwingungsspektrums von Anthracen werden begründet.
IR‐ und 17O‐NMR‐Spektren und Struktur einiger isomerer o‐Arylazonaphthole. Nachweis einer Karbonylvalenzschwingung bei 1570 cm−1 mittels 18O‐Substitution
Authors: Lippert E. , Samuel D. , Fischer E.
Published: March 2014

In 1‐Phenylazo‐2‐naphthol und in 2‐Phenylazo‐1‐naphthol liegt die Karbonylvalenzschwingung der Hydrazonform (Ih bzw. II in Abb. 1) bei 1570 cm−1 und nicht, wie bisher angenommen wurde, bei 1625 cm−1. Wegen des hohen Anteils der Grenzstrukturen vom Typ Ih an der Elektronenstruktur der Hydrazonform ist der Doppelbindungscharakter der Karbonylgruppe (etwa auf 2/3) stark erniedrigt. Bei den beiden intensiven Banden bei 1625 und 1600 cm−1 handelt es sich um Ringschwingungen. Dies ist auch beim 2‐Hydroxy‐1‐naphthaldehydanil (V) der Fall, dessen C=N‐Valenzschwingung bei 1570 cm−1 liegt, wie mit Hilfe der 15N‐Substitution gezeigt wird. Der Nachweis der Karbonylvalenzschwingung ist der erste unmittelbare Beweis dafür, daß es sich bei der längerwellig absorbierenden Form des im UV‐Absorptionsspektrum beobachteten lösungsmittelabhängigen Gleichgewichtes tatsächlich um die Hydrazonform handelt. Bei 3‐Phenylazo‐2‐naphthol (III) liegt das Gleichgewicht stark auf der Seite der Azoform, was auch aus der geringen Neigung zum Sauerstoffaustausch mit D218O hervorgeht.
Konzentrations‐ und Temperaturabhängigkeit des Isotopieeffektes bei der Ionenwanderung des Lithiums in essigsaurer Lösung. V. Mitteilung über Gegenstromelektrolyse
Authors: Behne D. , Wagener K.
Published: March 2014

Es werden Meßergebnisse über die Konzentrations‐ und Temperaturabhängigkeit des Isotopieeffektes bei der Ionenwanderung des Lithiums in n/2‐Essigsäure mitgeteilt. Die Bestimmung der Isotopieeffekte erfolgt aus dem stationären Entmischungsgrad, der bei einer Gegenstromelektrolyse erreicht wird und beruht auf Relativmessungen, bei denen jeweils eine Rb‐Cs‐Trennung zur Eichung der Trennsäule dient. Zu diesem Zweck wurde die Beweglichkeitsdifferenz von Rb+ und Cs+ im Temperaturbereich von 5–55°C und im Konzentrationsbereich von 0–0,1 molal aus Messungen von Voisinet und nach eigenen Messungen direkt ermittelt.

Der Isotopieeffekt bei der Ionenwanderung des Lithiums zeigt nur eine sehr geringe Temperaturabhängigkeit, hingegen eine überraschend starke Abhängigkeit von der Konzentration des Lithiumacetats in der Lösung. In sehr verdünnten Lösungen beträgt der Isotopieeffekt etwa 3,8‰, in 0,056 normaler Lösung 18,6‰. Als Ursache für diese abnorm große Zunahme wird ein Isotopieeffekt im Dissoziationsgleichgewicht des Li‐Acetats vermutet. Danach wäre ein Maximum des Isotopieeffekts in etwa 0,5 normaler Acetatlösung zu erwarten.
Schwingungs‐ und Rotationsschwingungsbanden von Methyl‐ und N‐Deutero‐Methylamin. Grund‐ und Obertöne der NH‐ und ND‐Valenzschwingungen
Authors: Wolff H. , Wolff E.
Published: March 2014

Die Ultrarotbanden von gasförmigem Methyl‐ und N‐Deutero‐Methylamin in den Spektralgebieten, die den Grund‐ und Obertönen der NH‐ und ND‐Valenzschwingungen zukommen, werden bei einer Auflösung von etwa 0,5 cm−1 gemessen. Dabei wird es möglich, folgende Banden einer Rotationsanalyse zu unterwerfen: von CH3NH2 die Banden der NH‐Valenzschwingungen und des Kombinationstons aus NH‐Deformationsschwingung und antisymmetrischer NH‐Valenzschwingung, von CH3ND2 die Bande des ersten Obertons der antisymmetrischen ND‐Valenzschwingung.

Besonders bei CH3ND2 wird festgestellt, daß die K‐Niveaus der Parallelbanden im P‐Zweig bei kleineren Werten von J aufspalten als im R‐Zweig. Die Beobachtung wird daraus erklärt, daß die Molekel bei den betreffenden Schwingungen im angeregten Zustand eine geringere Asymmetrie als im Grundzustand besitzt. Im Gebiet der ersten Obertöne wird neben der eindeutig zuzuordnenden Bande des Obertons der antisymmetrischen Aminogruppenschwingung sowohl bei CH3NH2 als auch bei CH3ND2 eine Bande mit zentralem Minimum und ohne aufgelöste Rotationsstruktur wahrgenommen. Sie wird damit gedeutet, daß sich in ihr die Banden des Obertons der symmetrischen Schwingung und des Kombinationstons aus symmetrischer und antisymmetrischer Schwingung überlagern. Eine solche Deutung ist im Einklang mit den Ergebnissen einer Analyse der NH‐Valenzoberschwingungen von CH3NH2 bei der unter Auffassung der Aminmolekel als Drei‐Massen‐System die Wellenzahlen von Ober‐ und Kombinationston aus den Wellenzahlen der anderen Schwingungen berechnet werden.
Die Banden der NH‐Valenzschwingungen von CH3NH2 und die bei CH3ND2 allein mit hinreichender Auflösung beobachtete Bande der antisymmetrischen ND‐Valenzschwingung zeigen charakteristische Intensitätswechsel der Subbanden. Davon ausgehend, daß der Methylrest bei der Aminogruppe nur als Störfaktor wirkt, werden die Intensitätswechsel versuchsweise aus dem Einfluß des Kernspins der H‐ und D‐Atome erklärt.
Bestimmung anodischer Wasserstoff/Deuterium‐Trennfaktoren an Edelmetallelektroden
Authors: Lauer H. , Vielstich W.
Published: March 2014

In dieser Arbeit wird der Isotopieeffekt bei der anodischen Oxydation von Wasserstoff untersucht. Hierzu wurde die Änderung der Gaszusammensetzung eines im Kreislauf geführten Gasgemisches während der anodischen Oxydation bei verschiedenen Elektrodenpotentialen zeitlich verfolgt. Die erhaltenen Ergebnisse wurden mit den anodischen Strom/Spannungs‐Kurven für Wasserstoff und Deuterium verglichen.

An rasch rotierenden Elektroden aus Platin und Gold wurde gefunden, daβ der anodische Trennfaktor in der Nähe von eins liegt, d.h., daβ praktisch kein Trenneffekt auftritt. Aus den entsprechenden Strom/Spannungs‐Kurven (bei verschiedenen Rotationsgeschwindigkeiten) ist zu schließen, daβ Adsorption und/oder Dissoziation der H2‐ bzw. HD‐ bzw. D2‐Moleküle geschwindigkeitsbestimmend sind und für diese Moleküle etwa gleich rasch verlaufen. Durch Verwendung von wasserstoffdurchlässigen Membranelektroden (aus Palladium/Silber‐ und Palladium/Platin‐Legierungen) mit gasseitiger Palladinierung ist es gelungen, die vorgelagerten Reaktionen (Adsorption und Dissoziation) unabhängig von der Durchtrittsreaktion so zu beschleunigen, daR die anodische Oxydation zum langsamsten Teilschritt wurde. Die unterschiedliche Oxydationsgeschwindigkeit so wie die Verschiebung des Isotopenverhältnisses zwischen Gas‐ und Metallphase führen zu einem Trennfaktor zwischen 1,3 und 2.
Die elektromotorische Kraft der galvanischen Zelle Pt(H2)/HJ(m)[AgJ]/Ag im Temperaturbereich von 20 bis 200°C
Authors: Kortüm G. , Hävssermann W.
Published: March 2014

Aus EMK‐Messungen an der Zelle Pt(H2)/HJ(m) [AgJ]/Ag im Bereich von 20 bis 200°C werden das Standard‐ potential der Ag[AgJ]‐Elektrode und die Aktivitätskoeffizienten verdünnter HJ‐Lösungen ermittelt. Es zeigte sich, daß bei sorgfältigem Sauerstoffausschluß die Zelle auch mit ungepufferten Lösungen reproduzierbare EMK‐Werte liefert. Das Standardpotential der Ag[AgJ]‐Elektrode läßt sich in Abhängigkeit von der Temperatur durch die Beziehung

magnified image

im Bereich von t = 20°C bis t = 145°C wiedergeben. Oberhalb von 145°C beobachtet man Abweichungen von dieser Ausgleichsformel, die damit zusammenhängen, daß Silberjodid bei 144,6°C in eine andere Modifikation übergeht. Die Umwandlungswärme des Silberjodids läßt sich aus der T‐Abhängigkeit dieser Abweichungen zu 6 ± 0,5 [kJ] berechnen in Übereinstimmung mit kalorischen Daten.
Zur Bestimmung der Komplexbildungskonstanten der Thallium‐III‐azid‐komplexe
Authors: Vogt G. G.
Published: March 2014

Die Komplexbildung zwischen Tl(III)‐ und Azidionen wird in perchlorsaurem Medium durch potentiometrische Titration des Systems Tl(I)/Tl(III) näher untersucht. Für die Versuchsbedingungen ‐ [H+] = 1,0 mol/l und Ionenstärke μ = 2,0 ‐ werden Tl(III)‐komplexe mit maximal drei Azidliganden gefunden. Die Bruttobildungskonstanten dieser Komplexe sind für die Temperaturen 12,7, 20, 35 und 50°C angegeben.
Über auswählende Solvatation von Ionen in Lösungsmittelgemischen. III
Authors: Schneider Hermann , Strehlow Hans
Published: March 2014

Die auswählende Solvatation von Zink‐und Chlorionen in den Lösungsmittelmischungen Wasser‐Hydrazin und Wasser‐Acetonitril wurden mit der Überführungsmethode bestimmt. Das Zinkion wird im ersten System von Hydrazin, im zweiten von Wasser bevorzugt solvatisiert. Dies Ergebnis ist in Übereinstimmung mit Abschätzungen der freien Überführungsenthalpien des Zinkions in diesen Lösungsmittelpaaren.
Nuclear Magnetic Resonance Spectra of the [AXn]3 Spin System. Part II. 19F NMR Spectra of fac‐Trisubstituted Fluorophosphine Molybdenum Complexes
Authors: Harris R. K. , Woplin J. R. , Schmutzler R.
Published: March 2014

The theory for the X spectrum of an [AXn]3 C3v spin system is developed for the case |J AX |≥ JAA |≥JAX |≥ JXX = 0. The spectra of four molybdenum complexes with phosphorus‐containing ligands are analysed on this basis. The sign of 3JPF is found to be positive. The coupling constants are discussed. The magnitude of 2JPP increases as the electronegativity of the groups attached to the phosphorus atoms increases. The sign of 4JFF is opposite to that of 2JPP.
Die Messung von Ion‐Molekül‐Reaktionen in der Gasphase mittels Pulsradiolyse am Beispiel des N2+ (2Σg+)
Authors: Perner D. , Dreyer J. W.
Published: March 2014

Es wird eine Methode zur kinetischen Absorptionsspektrometrie von thermischen Ionen beschrieben mil einer Zeitauflösung von kleiner als 10ns. Damit wurden die folgenden Geschwindigkeitskonstanten für Reaktionen des N2+(2Σg+; v″ = 0) bestimmt: magnified image