Relaxation of loose agglomerates of magnesium hydroxide in a polymer melt

International audienceThe study of agglomerates of magnesiumhydroxide badly dispersed in an olefinic polymer by means of oscillatory shear flow in the melt indicates that the agglomerates behave as a distinct phase. Optical and rheo-optical measurements carried out on these agglomerates also show that they are wetted by the melt and that they can be easily deformed under shear. However, the relaxation of shape in oscillatory shear is also the trace of the existence of an effective interfacial tension between the agglomerates containing high amounts of filler and the polymer matrix. The analogy with the behavior of polymer blends and the modeling by the Palierne model enables the calculation of such an interfacial tension. The surface free energy of magnesiumhydroxide that can be calculated from this result by a simple mixing law is 95 mN m−1. This value is compared with data from the literature on brucite and similar minerals

別居後の親権の共同行使

pp.29-28は、松川 正毅 教授による付

La violencia sexual como genocidio: memoria de las mujeres mayas sobrevivientes de violación sexual durante el conflicto armado en Guatemala

Este artículo es producto de la investigación/acción participativa llevada a cabo del 2005 al 2009 en el marco del proceso político y social impulsado por "Actoras de Cambio" junto con 54 mujeres mayas de cuatro grupos étnicos distintos -Q'eqchi', Mam, Chuj, y Kaqchikel- sobrevivientes de violación sexual durante el conflicto armado interno en Guatemala (1960-1996). En él analizamos el uso sistemático y masivo de la violación sexual contra las mujeres mayas dentro del marco de la política contrainsurgente en Guatemala, nombrándolo y denunciándolo como feminicidio y genocidio; evidenciamos cómo la violación sexual fue utilizada por el Estado para destruir la continuidad biológica, social y cultural del pueblo maya a través del cuerpo de las mujeres. Además, demostramos la centralidad e intencionalidad política de la violación sexual para someter y masacrar a las mujeres. El trabajo se estructuró con base en una epistemología feminista articulada con la de la cosmovisión maya. Ello implicó poner en el centro de la investigación voces y experiencias silenciadas por la visión androcéntrica y racista del mundo. Requirió, además, una voluntad colectiva de desvelar cómo se imbrican y sintetizan los diferentes sistemas de opresión en el cuerpo de mujeres mayas. Esta investigación da cuenta de una experiencia concreta y colectiva de memoria y sanación entre mujeres mayas, mestizas y europeas, que ha posibilitado rehabitar el cuerpo, la vida y la comunidad después de la violación sexual genocida desde un nuevo lugar justo, digno y libre para las mujeres.This paper is the outcome of a research/participatory action carried out from 2005 to 2009 in the context of the political and social process driven by "Women Agents of Change", along with 54 Mayan women from four different ethnic groups -Q'eqchi', Mam, Chuj, and Kaqchikel-, who survived sexual violation during the internal armed conflict in Guatemala (1960-1996). We survey the systematic and widespread use of rape against Mayan women within the framework of the Guatemalan counterinsurgency policy, labeling and denouncing it as feminicide and genocide. We demonstrate how rape was used by the State to annihilate the biological, social and cultural continuity of the Mayan people by way of the female body. In addition, we establish the political intention of using sexual violation to subdue and massacring women. The work was structured according to a feminist epistemology articulated with that of the Mayan worldview. Thus, the voices and experiences that had been silenced by an androcentric and racist stance were placed here as the focal point of the research. In addition, it required a collective will to expose how the different systems of oppression are interweaved and synthesized in the body of racialized women. This research accounts for a concrete and collective experience of memory and healing among Mayan, Mestizo and European women, which has made possible to inhabit again the body, the life, and the community after the genocidal sexual violation from a new dignified, just and free stance

La violencia sexual como genocidio: memoria de las mujeres mayas sobrevivientes de violación sexual durante el conflicto armado en Guatemala

Este artículo es producto de la investigación/acción participativa llevada a cabo del 2005 al 2009 en el marco del proceso político y social impulsado por "Actoras de Cambio" junto con 54 mujeres mayas de cuatro grupos étnicos distintos -Q'eqchi', Mam, Chuj, y Kaqchikel- sobrevivientes de violación sexual durante el conflicto armado interno en Guatemala (1960-1996). En él analizamos el uso sistemático y masivo de la violación sexual contra las mujeres mayas dentro del marco de la política contrainsurgente en Guatemala, nombrándolo y denunciándolo como feminicidio y genocidio; evidenciamos cómo la violación sexual fue utilizada por el Estado para destruir la continuidad biológica, social y cultural del pueblo maya a través del cuerpo de las mujeres. Además, demostramos la centralidad e intencionalidad política de la violación sexual para someter y masacrar a las mujeres. El trabajo se estructuró con base en una epistemología feminista articulada con la de la cosmovisión maya. Ello implicó poner en el centro de la investigación voces y experiencias silenciadas por la visión androcéntrica y racista del mundo. Requirió, además, una voluntad colectiva de desvelar cómo se imbrican y sintetizan los diferentes sistemas de opresión en el cuerpo de mujeres mayas. Esta investigación da cuenta de una experiencia concreta y colectiva de memoria y sanación entre mujeres mayas, mestizas y europeas, que ha posibilitado rehabitar el cuerpo, la vida y la comunidad después de la violación sexual genocida desde un nuevo lugar justo, digno y libre para las mujeres.This paper is the outcome of a research/participatory action carried out from 2005 to 2009 in the context of the political and social process driven by "Women Agents of Change", along with 54 Mayan women from four different ethnic groups -Q'eqchi', Mam, Chuj, and Kaqchikel-, who survived sexual violation during the internal armed conflict in Guatemala (1960-1996). We survey the systematic and widespread use of rape against Mayan women within the framework of the Guatemalan counterinsurgency policy, labeling and denouncing it as feminicide and genocide. We demonstrate how rape was used by the State to annihilate the biological, social and cultural continuity of the Mayan people by way of the female body. In addition, we establish the political intention of using sexual violation to subdue and massacring women. The work was structured according to a feminist epistemology articulated with that of the Mayan worldview. Thus, the voices and experiences that had been silenced by an androcentric and racist stance were placed here as the focal point of the research. In addition, it required a collective will to expose how the different systems of oppression are interweaved and synthesized in the body of racialized women. This research accounts for a concrete and collective experience of memory and healing among Mayan, Mestizo and European women, which has made possible to inhabit again the body, the life, and the community after the genocidal sexual violation from a new dignified, just and free stance

Kinetics of PE crystallization

A key issue in the understanding of the nascent polymerisation of ethylene, and on the development of the morphology of polyethylene (PE) particles is the competition between polymer growth and crystallization. In particular, in the case of production of PE in condensed mode cooling, the nascent polymer can be formed in conditions of extreme plastification – in other words, polymer can be formed under conditions where the nascent polymer is in a negligible concentration with respect to the alkanes present in the gas phase of the reactor. We have performed a series of thermal analyses to look at the rates of crystallization under isothermal conditions, and it has been observed that the time scale for the formation of crystals can actually be very long with respect to the times scale for the production of the individual polymer chains. This in turn can have a significant impact on mass transfer rates during the initial stages of polymerisation, as well as on the morphology of the particles as they are formed

Focus on some peculiar behaviors of polymers in the context of additive manufacturing processes

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Evaluate the nonlinear viscoelasticity of polyolefin melts using the Larson model

[[abstract]]Nonlinear rheological properties of polyolefins have long been studied and predicted by using the Larson model with the damping function generally obtained from the stress relaxation measurements. In this study, we investigate the nonlinear rheological properties of high density polyethylene (HDPE) and polypropylene (PP) using the Larson model with damping functions obtained from either the dynamic frequency sweep or the stress relaxation test. Experimental measurements and their corresponding model predictions for the rheological parameters were then compared to evaluate the applicability of the Larson model to the nonlinear rheology, and the following conclusions could be achieved. The steady shear viscosity could be satisfactorily described by the Larson model with the damping functions obtained from the two different methods, except at shear rates higher than 103 s-1. The predicted first normal stresses also account for the measured data, except for those using the stress relaxation data showing a little deviation for the PP sample. In addition, the predictions for elongation viscosity are also in good agreement with the experimental results within the short range of elongation rate achieved in this work.[[notice]]補正完畢[[incitationindex]]SCI[[incitationindex]]EI[[booktype]]紙本[[booktype]]電子

Experimentation and modeling for the apparent elongation viscosity of polymer melts with the White-Metzner model

[[abstract]]The measurement of the apparent elongation viscosity ( ) of several polyolefin melts was conducted in this study by using the isothermal fiber-spinning method. The White-Metzner (W-M) model was used to analyze the spinning flow of the polymer melts and, thus, the elongation viscosity was predicted at elongation strain rates ranging from 0 to approximately 5 s-1. The values of the model parameters required in the W-M model were obtained by curve-fitting the experimental data obtained from the shear measurements. The elongation viscosity predicted using the W-M model was in good agreement with the experimental results of fiber spinning. In addition, could also be estimated directly from the measured shear viscosity ( ) with a formulation using the W-M model; the subsequently obtained elongation viscosity and Trouton ratio ( ) were reasonable within a wide range of strain rates. Based on the experimental and theoretical results, the polyolefin with a high molecular weight was observed to have high elongation viscosity, and the polymer with a broad molecular weight distribution also possessed high . The TR value of the commercial polypropylene (PP-1040) began to increase from 3 at a deformation rate of 0.1 s-1 and grew up asymptotically to 10, whereas the TR of high-density polyethylene (HDPE-606) remained at 3 within the entire range of strain rates.[[notice]]補正完畢[[incitationindex]]SCI[[incitationindex]]EI[[booktype]]紙本[[booktype]]電子

“Ne répudiez point...” : Pour une interprétation raisonnée des arrêts du 17 février 2004

Fulchiron Hugues. “Ne répudiez point...” : Pour une interprétation raisonnée des arrêts du 17 février 2004. In: Revue internationale de droit comparé. Vol. 58 N°1,2006. pp. 7-26

Mariage et partenariats homosexuels en droit international privé français

Fulchiron Hugues. Mariage et partenariats homosexuels en droit international privé français. In: Revue internationale de droit comparé. Vol. 58 N°2,2006. pp. 409-438