al-Musnad [microform] /

Followed by al-Mujannad fī aḥwāl al-Musnad, by Muḥammad ʻAlī Akram al-Ārawī and Riḥlat al-Imām al-Shāfiʻī, by al-Suyūṭī.

Kitāb Manāhij al-albāb al-Miṣrīyah fī mabāhij al-ādāb al-ʻaṣrīyah /

Mode of access: Internet.

Kitāb Aḥkām al-awqāf [microform] /

Includes bibliographical references.

Kitāb al-kāmil [microform] /

Vol. 2 t.p.: The kāmil of El-Mubarrad / edited by W. Wright.

Leshon ha-zahav : ʻal masekhet Berakhot, Shabat, ʻEruvin...

Mode of access: Internet.

La no-identidad en T. W. Adorno : Entre la filosofía y la estética. Notas introductorias

En este trabajo busco introducir algunas problemáticas introductorias para entender la idea de no-identidad en Adorno. Teniendo en cuenta cómo Adorno plantea de modo materialista y dialéctico la preeminencia del objeto, trato de mostrar la problemática idea de naturaleza como un más allá del límite del concepto, una vez que el concepto calla frente al dolor y el vacío de una racionalidad cosificada. Para tal, se hace fundamental la noción de mímesis trabajada por Adorno en la Teoría estética, ya que es a través del arte como intervalo entre naturaleza y concepto que este tendrá la oportunidad de su redención, ya que, aunque Adorno afirme que sólo el concepto puede venir a conocer el concepto, el arte parece ser la instancia capaz de despertarlo para su condición misma

La no-identidad en T. W. Adorno : Entre la filosofía y la estética. Notas introductorias

En este trabajo busco introducir algunas problemáticas introductorias para entender la idea de no-identidad en Adorno. Teniendo en cuenta cómo Adorno plantea de modo materialista y dialéctico la preeminencia del objeto, trato de mostrar la problemática idea de naturaleza como un más allá del límite del concepto, una vez que el concepto calla frente al dolor y el vacío de una racionalidad cosificada. Para tal, se hace fundamental la noción de mímesis trabajada por Adorno en la Teoría estética, ya que es a través del arte como intervalo entre naturaleza y concepto que este tendrá la oportunidad de su redención, ya que, aunque Adorno afirme que sólo el concepto puede venir a conocer el concepto, el arte parece ser la instancia capaz de despertarlo para su condición misma

Method for determining reaction rate of mild steel containers during melting of magnesium-aluminium alloys and effect of aluminium content on directionally solidified microstructures

A magnesium alloy of eutectic composition (33 wt-'%Al) was directionally solidified in mild steel tubes at two growth rates, 32 and 580 mum s(-1,) in a temperature gradient between 10 and 20 K mm(-1). After directional solidification, the composition of each specimen varied dramatically, from 32'%Al in the region that had remained solid to 18%Al (32 mum s(-1) specimen) and 13%Al (580 mum s(-1) specimen) at the plane that had been quenched from the eutectic temperature. As the aluminium content decreased, the microstructure contained an increasing volume fraction of primary magnesium dendrites and the eutectic morphology gradually changed from lamellar to partially divorced. The reduction in aluminium content was caused by the growth of an Al-Fe phase ahead of the Mg-Al growth front. Most of the growth of the Al-Fe phase occurred during the remelting period before directional solidification. The thickness of the Al-Fe phase increased with increased temperature and time of contact with the molten Mg-Al alloy. (C) 2003 Maney Publishing.

Transmission electron microscopy sample preparation technique for sintered alloys

Powder metallurgy alloys are typically inhomogeneous with a significant amount of porosity. This complicates conventional transmission electron microscopy sample preparation. However, the use of focused ion beam milling allows site specific transmission electron microscopy samples to be prepared in a short amount of time. This paper presents a method that can be used to produce transmission electron microscopy samples from an Al-Cu-Mg PM alloy. (C) 2003 IoM Communications Ltd. Published by Maney for the Institute of Materials, Minerals and Mining.

The effect of iron on liquid film migration and sintering of an Al-Cu-Mg alloy

Analytical transmission electron microscopy indicates that liquid film migration occurs during sintering of an Al-Cu-Mg alloy, that intragranular liquid pools develop from migrating films and that iron segregates to these pools. It is suggested that a high localised iron concentration retards the liquid film migration rate by reducing the coherency strain in the retreating grain, causing a region of the film to detach from the boundary, thus forming an intragranular pool in the advancing grain. Alloys with low iron levels develop few intragranular pools and have high sintered densities. (C) 2003 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.

Microstructure and mechanical properties of high pressure die cast magnesium alloy AE42 with 1% strontium

The addition of 1 wt-%Sr to AE42 results in an improvement in the tensile strength of the alloy at elevated temperatures of 150 and 175degreesC and an improvement in the constant load creep properties at 175degreesC. The improved elevated temperature tensile and creep strength of the alloy can be attributed to the presence of a strontium-containing phase in the microstructure of the alloy along with an increase in the stability of the microstructure of the alloy at high temperatures. (C) 2004 W. S. Maney Son Ltd.

Grain size measurements in Mg-Al high pressure die castings using electron back-scattered diffraction (EBSD)

Optical metallographic techniques for grain-size measurement give unreliable results for high pressure diecast Mg-Al alloys and electron back-scattered diffraction mapping (EBSD) provides a good tool for improving the quality of these measurements. An application of EBSD mapping to this question is described, and data for some castings are presented. Ion-beam milling was needed to prepare suitable samples, and this technique is detailed. As is well-known for high pressure die castings, the grain size distribution comprises at least two populations. The mean grain size of the fine-grained population was similar in both AZ91 and AM60 and in two casting thicknesses (2 mm and 5 mm) and, contrary to previously published reports, it did not vary with depth below the surface.

Grain coarsening of magnesium alloys by beryllium

A trace of beryllium can lead to dramatic grain coarsening in Mg-Al alloys at normal cooling rates. It is, however, unclear whether this effect applies to aluminium-free magnesium alloys or not. This work shows that a trace of beryllium also causes considerable grain coarsening in Mg-Zn, Mg-Ca, Mg-Ce and Mg-Nd alloys and hinders grain refinement of magnesium alloys by zirconium as well. (C) 2004 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Segregation band formation in Al-Si die castings

Banded defects are often found in high-pressure die castings. These bands can contain segregation, porosity, and/or tears, and changing casting conditions and alloy are known to change the position and make-up of the bands. Due to the complex, dynamic nature of the high-pressure die-casting (HPDC) process, it is very difficult to study the effect of individual parameters on band formation. In the work presented here, bands of segregation similar to those found in cold-chamber HPDC aluminum alloys were found in laboratory gravity die castings. Samples were cast with a range of fraction solids from 0 to 0.3 and the effect of die temperature and external solid fraction on segregation bands was investigated. The results are considered with reference to the theological properties of the filling semisolid metal and a formation mechanism for bands is proposed by considering flow past a solidifying immobile wall layer.