Search results for "Homogeneous"
showing 10 items of 718 documents
Current Problems in the Modelling of Photochemical Reactors
1985
Photochemical reactors are examined from the point of view of the main problems connected to their modelling. By distinguishing the diverse meanings of kinetic models and the varied objectives in establishing models, a particular attention is devoted to the following aspects of homogeneous photoreactors: steady state condition, effect of stirring and mixing, effect of the shape of the reactor and of the position of the light source, light emission models, scale up. For the heterogeneous systems only general considerations on kinetic models in heterogeneous photocatalysis and on the problems related to the use of fluidized bed photoreactors are done.
A Dichoptic Edge Effect Resulting from Binocular Contour Dominance
1980
If one eye sees a bright field on a dark surround while a homogeneous background is presented to the other eye, then a distinct dark zone appears at the outer borders of the field.If the surround is coloured, then the zone is of corresponding hue. The effect disappears if the edge of the field can be fused with a bar of appropriate contrast. The influence of parameters such as pattern contrast and size were studied quantitatively. A model is proposed relating the effect to receptive-field organisation and the fusion process.
Dictionnaire Bilingue, Syntaxe et Sémantique
1995
We have first shown that the conventional and theoretical lexicography has always had a semantic basis which does not permit homogeneous analysis of the items which constitute the entries. We present in this paper a model of bilingual dictionary whose fundamental principles are syntactical. This dictionary is an application of the methods of the Lexique-grammaire des langues romanes adapted to contrastive viewpoint. This contrastive aim implicates that we have to make specific analytic distinctions which we comment here. On the one hand, from a theoretical standpoint, this dictionary may help to establish suitable basis of systematic contrastive (French/Spanish) linguistics, and on the othe…
Simetries de mirall en l’ordre intern de les construccions absolutes: del català antic al català actual
2016
Resum: Se sol assumir que les construccions absolutes manifesten les mateixes propietats sintàctiques i interpretatives que les subordinades adverbials però, en contrast amb aquestes, no disposen d’un subordinant explícit. En aquest article argumentarem en contra d’aquesta idea. Partint de l’anàlisi de la dislocació del subjecte en el català primitiu i en l’actual, justificarem que les CA encapçalades per una vegada i un cop en català tenen un subordinant format composicionalment per dues porcions discontinues: d’una banda, una preposició incorporada en l’estructura sublèxica del participi, seguint la proposta de Gallego & Hernanz (2012) i, de l’altra, una expressió temporal (una vegada, un…
Encapsulació i estructura informativa en el debat parlamentari. Una anàlisi contrastiva (català – espanyol – anglès)
2016
Parliamentary debate (PD) as a specific genre of parliamentary discourse exhibits a hybrid nature: part oral and part written discourse. It is performed orally, but planned ahead and formal. From the point of view of lexical cohesion, encapsulation by means of abstract and unspecific nouns (e.g. factor reason) is an indicator of the informative density and the underlying written natureof PD.With the tools provided by Discourse Analysis and Cognitive Linguistics, this paper aims at describing and characterizing cross-linguistically lexical encapsulation’s potential to define the information struc-ture of PD. In this regard, encapsulation is analyzed in relation to the notions of topic and fo…
EFFECT OF A 48H DELAYED INSEMINATION WITH OR WITHOUT A 48H DOE-LITTER SEPARATION ON PERFORMANCE OF NON-RECEPTIVE RABBIT DOES
2010
[EN] The effectiveness of delayed artificial insemination (DAI) of non-receptive (R-) does, with or without oestrus synchronisation by doe-litter separation (MLS), was studied and compared with receptive (R+) does. During 10 months, 105 NZW does, in three homogeneous groups (A, B, C), were artificially inseminated (Al) according to a 42-day reproduction rhythm in two batches. Every 21 days, two Al were effected, the second 48 hours alter the first. The R+ does of ali groups were inseminated al the first Al, while the R- does were treated, in relation to theirgroup, as follows: inseminated at the first Al (A); 48-hour DAI (B); 48-hour MLS by closing the nestbox before Al, when lactating, and…
Surveillance Program for Diagnosis of HCC in Liver Cirrhosis: Role of Ultrasound Echo Patterns
2017
International guidelines suggest ultrasound surveillance for hepatocellular carcinoma (HCC) early diagnosis in liver cirrhosis (LC) patients, but 40% of nodules <2 cm escape detection. We investigated the existence of an ultrasound pattern indicating a higher risk of developing HCC in patients under surveillance. 359 patients with LC (Child-Pugh A-B8) underwent ultrasound screening (median follow-up 54 months, range 12–90 months), liver function tests, alpha-fetoprotein assay, and portal hypertension evaluation. Echo patterns were homogeneous, bright liver, coarse, coarse small nodular pattern, and coarse large nodular pattern. During follow-up 13.9% developed HCC. At multivariate analys…
The Bruce–Roberts Number of A Function on A Hypersurface with Isolated Singularity
2020
AbstractLet $(X,0)$ be an isolated hypersurface singularity defined by $\phi \colon ({\mathbb{C}}^n,0)\to ({\mathbb{C}},0)$ and $f\colon ({\mathbb{C}}^n,0)\to{\mathbb{C}}$ such that the Bruce–Roberts number $\mu _{BR}(f,X)$ is finite. We first prove that $\mu _{BR}(f,X)=\mu (f)+\mu (\phi ,f)+\mu (X,0)-\tau (X,0)$, where $\mu $ and $\tau $ are the Milnor and Tjurina numbers respectively of a function or an isolated complete intersection singularity. Second, we show that the logarithmic characteristic variety $LC(X,0)$ is Cohen–Macaulay. Both theorems generalize the results of a previous paper by some of the authors, in which the hypersurface $(X,0)$ was assumed to be weighted homogeneous.
Symmetries and Covariance of the Maxwell Equations
2012
Already within a given, fixed division of four-dimensional spacetime into the space where experiments are performed, and the laboratory time variable, Maxwell’s equations show interesting transformation properties under continuous and discrete space-time transformations. However, only the action of the whole Lorentz group on them reveals their full symmetry structure. A good example that illustrates the covariance of Maxwell’s equations is provided by the electromagnetic fields of a point charge uniformly moving along a straight line.
M-theory, graphene-branes and superconducting wormholes
2017
Exploiting an M-brane system whose structure and symmetries are inspired by those of graphene (what we call a graphene-brane), we propose here a similitude between two layers of graphene joined by a nanotube and wormholes scenarios in the brane world. By using the symmetries and mathematical properties of the M-brane system, we show here how to possibly increase its conductivity, to the point of making it as a superconductor. The questions of whether and under which condition this might point to the corresponding real graphene structures becoming superconducting are briefly outlined.