Showing papers on "Valency published in 2017"

Mixed Valency as a Strategy for Achieving Charge Delocalization in Semiconducting and Conducting Framework Materials

Abstract: The fundamentally important phenomenon of mixed valency has been discussed in detail over the past 50 years, predominantly in the context of dinuclear complexes, which are used as model systems for understanding electron delocalization in more complex biological and physical systems. Very recently, mixed valency has been shown to be an important mechanism for charge transfer, leading to delocalization and conductivity in two- and three-dimensional framework materials such as metal–organic frameworks and related systems including covalent organic frameworks and semicrystalline semiconducting metal–organic graphenes. This Viewpoint provides a current perspective on the field of mixed-valence frameworks, where the property is either intrinsic or generated postsynthetically via an external stimulus. Aspects of the spectroscopy and applications of these materials are also discussed, highlighting the future potential for exploiting mixed valency in extended solid-state systems.

Effective Electrostatic Interactions Between Two Overall Neutral Surfaces with Quenched Charge Heterogeneity Over Atomic Length Scale

Abstract: Using Monte Carlo results as a reference, a classical density functional theory (CDFT) is shown to reliably predict the forces between two heterogeneously charged surfaces immersed in an electrolyte solution, whereas the Poisson–Boltzmann (PB) theory is demonstrated to deteriorate obviously for the same system even if the system parameters considered fall within the validity range of the PB theory in the homogeneously charged surfaces. By applying the tested CDFT, we study the effective electrostatic potential of mean force (EPMF) between two face–face planar and hard surfaces of zero net charge on which positive and negative charges are separated and considered to present as discontinuous spots on the inside edges of the two surfaces. Main conclusions are summarized as follows: (i) strength of the EPMF in the surface charge separation case is very sensitively and positively correlated with the surface charge separation level and valency of the salt ion. Particularly, the charge separation level and the salt ion valency have a synergistic effect, which makes high limit of the EPMF strength in the surface charge separation case significantly go beyond that of the ideal homogeneously charged surface counterpart at average surface charge density similar to the average surface positive or negative charge density in the charge separation case. (ii) The surface charge distribution patterns mainly influence sign of the EPMF: symmetrical and asymmetrical patterns induce repulsive and attractive (at small distances) EPMF, respectively; but with low valency salt ions and low charge separation level the opposite may be the case. With simultaneous presence of both higher valency cation and anion, the EPMF can be repulsive at intermediate distances for asymmetrical patterns. (iii) Salt ion size has a significant impact, which makes the EPMF tend to become more and more repulsive with the ion diameter regardless of the surface charge distribution patterns and the valency of the salt ion; whereas if the 1:1 type electrolyte and the symmetrical patterns are considered, then the opposite may be the case. All of these findings can be explained self-consistently from several perspectives: an excess adsorption of the salt ions (induced by the surface charge separation) serving to raise the osmotic pressure between the plates, configuration fine-tuning in the thinner ion adsorption layer driven by the energy decrease principle, direct Coulombic interactions operating between charged objects on the two face-to-face plates involved, and net charge strength in the ion adsorption layer responsible for the net electrostatic repulsion.

Valency effects of cation dopant on ultraphosphate glass electrolytes for intermediate temperature fuel cells

Abstract: Some solid phosphates show high protonic conductivity in the intermediate temperature range at 150­250°C. Although the conductivity of crystalline phosphate materials, such as CsH2PO4 and CsHSO3, is high at intermediate temperature, it decreases significantly below phase transition temperature. In order to quench the structure of the high temperature phase with high conductivity, non-crystalline ultraphosphate glasses without phase transition in the wide temperature range at 25­250°C were evaluated. In the present work, the valency effects of cation dopant on protonic conductivity and glass structure were investigated. The P­O bonding was strengthened by doping trivalent La, which decreased proton conductivity. On the other hand, orthophosphate and end phosphate structures were formed by doping univalent Cs. The conductivity of 30Cs2O­70P2O5 glass was 1.7 © 1013 S/cm at 200°C. However, the production of free orthophosphoric acid deteriorated the chemical stability for Cs-doped phosphate glasses. The 30ZnO­70P2O5 glass has a potential as an electrolyte of intermediate temperature fuel cells, since a maximum power density of 1.2mW/cm2 was obtained at 200°C.

The Main Features of the e-Glava Online Valency Dictionary

Abstract: E-Glava is an online valency dictionary of Croatian verbs. The theoretical approach to valency follows the German tradition, particular ly that of the VALBU dictionary, with some minor changes and adjustments. The main pri nciple of our valency approach is to link valency patterns to specific verb meanings. The verb list is compiled semi-automatically on the basis of the Croatian Frequency Dictionary and Croatian language textbooks. Currently, e-Glava contains descriptions of 57 psychologica l verbs with 187 meanings and 375 valency patterns. The lexicographic articles are written in Tschwanelex. A Document Type Definition editing module has been used, and the descriptio n of verbs follows a three-level linguistic schema prepared for lexicographers. Verbs are distributed throughout 34 semantic classes, and examples are extracted manually from Cr oatian corpora. Fully processed data for each semantic class will be publicly available in th e form of a browsable HTML dictionary. The paper also presents a comparison between e-Glava and other cognate resources, as well as a summary of its main advantages, disadv antages, and potential applied uses.

CzEngClass – Towards a Lexicon of Verb Synonyms with Valency Linked to Semantic Roles

Abstract: Abstract In this paper, we introduce our ongoing project about synonymy in bilingual context. This project aims at exploring semantic ‘equivalence’ of verb senses of generally different verbal lexemes in a bilingual (Czech-English) setting. Specifically, it focuses on their valency behavior within such equivalence groups. We believe that using bilingual context (translation) as an important factor in the delimitation of classes of synonymous lexical units (verbs, in our case) may help to specify the verb senses, also with regard to the (semantic) roles relation to other verb senses and roles of their arguments more precisely than when using monolingual corpora. In our project, we work “bottom-up”, i.e., from an evidence as recorded in our corpora and not “top-down”, from a predefined set of semantic classes.

Valency and expectation in Bantu applicatives

Abstract: Bantu applicatives are standardly analysed syntactically, as encoding a change in valency. However, in many cases applicatives do not change valency, but are rather related to a change in interpretation. In particular pragmatic functions of applicatives related to focus and emphasis are often noted in the description of individual languages, but are very rarely reflected in typological or theoretical work. To address this problem, this paper develops a pragmatic analysis of applicatives, in which applicatives signal that the action denoted by the base verb is being carried out in some way remarkably, and so differently from normal expectations about the action. Pragmatic effects are found with all uses of applicatives, and may lead to a change in valency, or not. Absence of a change in valency is found in particular with locative and instrument applicatives, while benefactive applicatives almost always entail a change in valency. This is related to the thematic hierarchy: Beneficiaries occupy a high position in the thematic hierarchy and have a strong effect on the expectedness of the action expressed. The advantage of our analysis is that it addresses both interpretational and structural aspects of applicative constructions and provides a unified explanation for them.

CP-recursion and the derivation of verb second in Germanic main and embedded clauses

Abstract: his paper will give an overview of the verb second (V2) phenomenon, as found in both main and embedded clauses in Germanic, and it will also explore a particular derivation of (embedded) V2, in terms of a cP/CP-distinction. All the Germanic languages except modern English (but including e. g. Old English) are V2, i. e. in all declarative main clauses and in all wh-questions, the inite verb is in the second position, regardless of whether the irst position is occupied by the subject or by some other constituent. his can be extended to yes/no-questions, provided it is assumed that the irst position in such questions is empty (and such an assumption is supported by the fact that it allows an account for Greenberg’s 1963: 83 “Universal 11”, cf. Vikner 2007). No particular type of embedded clause in Germanic ever requires V2, and although V2 is optionally possible in many embedded clauses, this is normally not the case for all types of embedded clauses, as e. g. embedded questions (almost) never allow V2 (Julien 2007, Vikner 2001, though see McCloskey 2006 and Biberauer 2015). As in Nyvad et al. (2016), I will explore a particular derivation of (embedded) V2, in terms of a cP/ CP-distinction, which may be seen as a version of the CP-recursion analysis (deHaan & Weerman 1986, Vikner 1995 and many others). he idea is that because embedded V2 clauses do not allow extraction, whereas other types of CP-recursion clauses do (Christensen et al. 2013a; Christensen et al. 2013b; Christensen & Nyvad 2014), CP-recursion in embedded V2 is assumed to be fundamentally diferent from other kinds of CP-recursion, in that main clause V2 and embedded V2 involve a CP (“big CP”), whereas other clausal projections above IP are instances of cP (“litle cP”).

Transitivity and valency in Northern Akhvakh

Abstract: This paper analyzes transitivity and valency in Northern Akhvakh, a language belonging to the Andic group of languages included in the Northeast Caucasian (or Nakh-Daghestanian) family. Northern Akhvakh clause structure is characterized by an extreme flexibility of constituent order, omissibility of arguments with an either anaphoric or unspecified reading, and fully consistent ergative coding of core NPs. Northern Akhvakh has a very low rate of transitivity prominence, and an extremely strong tendency to derive the causal member of noncausal / causal pairs from its noncausal counterpart. Ambitransitivity is very marginal, and the productivity of morphologically unmarked valency alternations is very limited. Causative derivation is the only valency changing mechanism involving verb morphology, and ingestion verbs are the only transitive verbs for which causative derivation is productive.

Syntaktická struktura komplexních predikátů v češtině

Abstract: In this paper, I describe the syntactic structure formation of Czech complex predicates with light verbs. I limit myself to a central type of Czech complex predicates, i.e. to the complex predicates composed of a light verb and a predicative noun expressed in the direct object. I demonstrate that in the deep syntactic structure, both the predicative noun and the light verb are characterized by their own valency complementations. In the deep structure, several nominal and verbal valency complementations are in coreference. I show that this coreference plays a crucial role in the distribution of valency complementations in the surface structure of complex predicates. Moreover, I introduce principles governing the surface structure formation of Czech complex predicates. On the basis of syntactically distinctive properties of complex predicates (the correspondence of the nominal ACTor with some of verbal complementations and the mapping of the semantic participant ‘Causator’ onto some of verbal complementations), I distinguish four types of complex predicates in Czech. Finally, I outline the open questions concerning the expression of the nominal ACTor and its coreference.

Pressure Induced Structural Phase Transition and Valence Change

Abstract: The application of hydrostatic pressure on a solid material has a direct effect on the extra-nuclear electronic states of the constituent atoms in the material. In this work, we have studied the effect of pressure on the various properties of the material, such as structural behavior, crystal lattice behavior, magnetic behaviors of magnetic material and transport behavior like electrical resistivity. We have calculated the Ce valency change in some compounds of cerium monochalcogenides CeX (X=O, S, Se and Te) and cerium monopnictides CeX (X=P, As, Sb and Bi). In doing this task, we have reproduced the reported experimental pressure-volume relationships of the compounds using the Birch equation of state. The corresponding pressure-volume relationships of these compounds for stable trivalent cerium have also been calculated using the same Birch equation. Clear effect of pressure on the cerium valency has been realized for each compound from the present calculation.

Deverbal Nouns in Czech Light Verb Constructions

Abstract: In this paper, we provide a well-founded description of Czech deverbal nouns in both nominal and verbal structures (light verb constructions), based on a complex interaction between the lexicon and the grammar. We show that light verb constructions result from a regular syntactic operation. We introduce two interlinked valency lexicons, NomVallex and VALLEX, demonstrating how to minimize the size of lexicon entries while allowing for the generation of well-formed nominal and verbal structures of deverbal nouns.

Classifications of Mundari Expressives and Other Reduplicated Structures Based on Phonological Patterns, Transitivity, and the Effects of Valency-Reducing Affixes

Abstract: Despite academic interest in the Munda languages of South Asia (Anderson 1999, Mohan 2008, Osada 1991, 2008) and their propensity for reduplication, previous work in this area does not address the resulting reduplicated structures' interactions with verbal morphology. I examine the valency of expressives, a class of ideophones in Mundari, comparing their behaviors as predicates to those of reduplicated verb forms. I further describe several valency-altering affixes indicating passive voice, reflexivity, and reciprocality, in conjunction with these reduplicated forms. I then propose a set of groupings for Mundari expressives based on valency and interaction with these affixes, complementing an existing classification by Toshiki Osada based on phonological patterns which I also expand upon. *1 would like to thank Professor Emily Gasser, my advisor, for her guidance, as well as my thesis readers Jordan Sciascia, Sal Little, Claire Benham-Chandler, and Professor K. David Harrison for their comments and critiques, my roommate Mollie Wild for her support and insistence that I obtain a reasonable number of hours of sleep per night, my mother for her encouragemen~ and my fellow inhabitants of Woolman dormitory for those many wonderful evenings spent surrounded by verbal morphology and tea. Glossing Abbreviations! 112/3 first/second/third person AM aspect marker COMPLE completive aspect DL dual plural EXCL exclusive plural INCL inclusive plural IND indefinite base ITR intransitive LaC locative OB) object agreement marker PL plural PRD predicator PV passIve RECIP reciprocal REFL reflexive SG singular SUB) subject agreement marker TR transitive IOf my three main sources, Hoffmann 1950, Osada 1991, and Osada 2008, only Osada's examples have glosses provided; all examples from Hoffmann have only a translation.

Possible but not probable :A quantitative analysis of valency behaviour of Czech nouns in the Prague Dependency Treebank

Abstract: Abstract In order to optimize corpus searches for valency lexicon production, we analyse the relative frequencies of different combinations of valency complementations of Czech deverbal nouns in the Prague Dependency Treebank, considering differences between productively and non-productively derived nouns and their semantic class. We also classify combinations of forms of participants according to their frequency.

Arc-transitive digraphs of given out-valency and with blocks of given size

Abstract: Given integers $k$ and $m$, we construct a $G$-arc-transitive graph of valency $k$ and an $L$-arc-transitive oriented digraph of out-valency $k$ such that $G$ and $L$ both admit blocks of imprimitivity of size $m$.