SIMULATION AND DESIGN 0f HEATING PROFILSS IN HEAT CONTROLLED FREEZE-DRYING OF PHARMACKUTICALS IN VIALS BY THE APPLICATION OF A SUBLIMATION SEMISPHERICAL MODEL.

The freeze-drying of a certain pharmaceutical contained in vials in industrial like conditions has been described by a sublimation model under analogous semispherical configuration. Several operating strategies were proved on the basis of considering three different stages during freeze-drying in relation with the modification of heating and product temperacure evolutions. The model offers interesting perspectives to obtain orientative simulated results in heating strategies analysis in order to reduce drying time.     

Decay of pavement mortar due to thaumasite formation

BACKGROUND: This paper discusses the formation of thaumasite in the mortar sub‐flooring used as a base material for laying tiles, and the influence of this mineral in relation to deterioration of building materials. An investigation of a mortar sub‐flooring constructed with dolomitic limestone sand with high sulfate content used to settle a ceramic pavement was carried out. RESULTS: The mortar sub‐flooring underwent an important deterioration process due to the formation of expansive compounds in the environmental conditions of temperature and humidity of the installation area in Murcia (Spain). Expansion appeared essentially at the interface between the ceramic tiles and the mortar sub‐flooring, an area consisting primarily of cement paste. CONCLUSION: Materials present in the soft pulpy mass were examined by X‐ray diffraction and scanning electron microscopy with energy‐dispersive X‐rays. The presence of thaumasite was detected, which had been formed under conditions of temperature higher than temperatures reported in the literature and with a high degree of humidity. Copyright © 2008 Society of Chemical Industry     

Improving the Decompilation of Java Bytecode to Prolog by Partial Evaluation

The interpretative approach to compilation allows compiling programs by partially evaluating an interpreter w.r.t. a source program. This approach, though very attractive in principle, has not been widely applied in practice mainly because of the difficulty in finding a partial evaluation strategy which always obtain “quality” compiled programs. In spite of this, in recent work we have performed a proof of concept of that, at least for some examples, this approach can be applied to decompile Java bytecode into Prolog. This allows applying existing advanced tools for analysis of logic programs in order to verify Java bytecode. However, successful partial evaluation of an interpreter for (a realistic subset of) Java bytecode is a rather challenging problem. The aim of this work is to improve the performance of the decompilation process above in two respects. First, we would like to obtain quality decompiled programs, i.e., simple and small. We refer to this as the effectiveness of the decompilation. Second, we would like the decompilation process to be as efficient as possible, both in terms of time and memory usage, in order to scale up in practice. We refer to this as the efficiency of the decompilation. With this aim, we propose several techniques for improving the partial evaluation strategy. We argue that our experimental results show that we are able to improve significantly the efficiency and effectiveness of the decompilation process.     

The chemo-protector effects of tea and its components

Tea has been consumed worldwide since ancient times to maintain and improve health. Its main active components are a type of polyphenols known as flavonoids, which include catechins and theaflavins. Several epidemiological studies suggest that the consumption of green tea could prevent cancer development in humans. Likewise, animal studies have shown that green tea consumption may inhibit the development of prostate and breast cancer. It has been shown that, through several mechanisms, tea polyphenols present antioxidant and anticarcinogenic activities, thus affording several health benefits. It is important to better characterize tea components, to study their bio-availability and bio-transformation in vivo and to conduct clinical studies of its main active compounds.     

Supercritical fluid extraction of energetic nitroaromatic compounds and their degradation products in soil samples

This paper explores the use of supercritical fluid extraction (SFE), in combination with various analyte collection strategies, for extracting energetic nitroaromatic compounds and their degradation products from soil samples. The required selectivity has been achieved by a combination of an SFE program and active trapping. Several different collection strategies were tested, using a selection of liquids (methanol, toluene, methyl tert-butyl ether, acetonitrile), inert and solid-phase extraction materials (Nexus, Oasis, LiChrolut), and 1-cm liquid chromatography precolumns (porous graphitic carbon, PGC). The best results were obtained using SFE in combination with a PGC precolumn. This setup allows on-line cleanup of the extract, and comparable results were obtained using either GC-ECD or GC-chemical ionization-MS for confirmatory analysis. The time required for a complete analysis was less than 60 min, and only 1 mL of toluene was needed for a 0.5-g representative sample. In contrast, the EPA standard method 8330 required 18-h sonication and 20 mL of acetonitrile for a 4.0-g sample and further time for sample cleanup and HPLC analysis. The method presented here provides method detection limits in the low-nanogram range, with relative standard deviations lower than 7%. The optimized method has been compared and validated with EPA method 8330 in terms of efficiency parameters such as robustness, accuracy (trueness and precision), and capability of detection. The validation demonstrated that the two analytical methodologies give comparable performance for the determination of nitroaromatic compounds, but SFE is superior for analyzing amine degradation products.     

Effect of substitution of aspartame for sucrose on instrumental texture profile of hydrocolloids gelled systems

The effect of substituting aspartame (0.04–0.16% w/w) for sucrose (5–25% w/w) on the instrumental texture profile of three hydrocolloid gelled systems: -carrageenan, gellan gum and -carrageenan/locust bean gum at three different concentrations (0.3, 0.75 and 1.2% w/w) was studied. In gellan gels hardness and chewiness increased with sucrose concentration but not so in either -carrageenan or -carrageenan/LBG gels where no changes in these parameters were detected. Addition of sucrose also produced a small but significant increase in cohesiveness in gellan gels. The effect of sucrose concentration on all texture parameters of gellan gels was higher as gellan concentration increased. Aspartame addition did not affect TPA parameters. TPA results obtained for aspartame gels did not differ from those corresponding to the unsweetened gels considered here. Summarising the above information it can be said that substituting aspartame for sucrose in this type of sweetened gel changed the textural properties and that the changes produced depended on the hydrocolloid type and concentration and on the sucrose concentration replaced.     

Geographical discrimination of honeys through the employment of sugar patterns and common chemical quality parameters

 Sixty honey samples from six different production zones of the provinces of Salamanca, Zamora and Cáceres (west Spain) were analyzed for 13 common legal physico-chemical parameters and 17 sugars in order to test for their geographical classification. Application of linear stepwise discriminant analysis to a number of variables made of a selection of analytical results and simple mathematical functions of them allowed, firstly, discrimination between honeys from these six zones and, secondly, discrimination between honeys from the three zones of the province of Salamanca. The eight most discriminant variables selected for the six zones were a combination of nine physico-chemical parameters and sugars, with 85.00% of correctly classified samples; for the three zones of the province of Salamanca, regarded with special interest in our study, seven variables were selected (consisting of seven single physico-chemical parameters and sugars) with a result of 100.00% of correctly classified samples. Received: 3 May 1999 / Revised version: 30 July 1999     

The chemical mechanisms of outdoor weathering in polyvinyl chloride

Polyvinyl chloride weathering is a free radical mechanism started by absorption of energy sufficient to break chemical bonds. Absorption chromophores are often related to PVC heat history. Chemical bond energies are examined to indicate weak sites susceptible to initial degradation. Mechanisms of yellowing, oxidation, bleaching, and surface erosion are described. Some of the techniques for controlling the degradation of PVC are described. These techniques allow the PVC degradation to be controlled sufficiently so that PVC is accepted commercially as an excellent outdoor weathering material.     

Between the Sacred and Secular: The Role of Chinese Popular Deities in Creating Thirdspaces in Chinese Restaurants of Santiago de Chile

Abstract

Material manifestations of the Chinese popular deities, Guanyin and Guan Gong, are ubiquitous in Cantonese-Chinese restaurants globally. Yet studies of Chinese popular religion among overseas Chinese have seldom focused on the diverse significance of these deities to Chinese migrants, nor the use of restaurant-spaces to house these deities. This article examines the presence and powers of such deities in Chinese restaurants of Santiago de Chile. We seek to understand how the presence or absence of Guanyin and Guan Gong figures specifically shapes migrant Chinese restauranteurs and workers’ experience of the restaurants as particular kinds of protected, sacred/secular spaces, and how these deities might also affectively shape the restauranteurs’ ways of being and inhabiting the restaurants. Based on semi-structured interviews with Chinese shopkeepers and workers, observation and photography of the spatial organization of 26 restaurants and the aesthetics of their deities, we argue that these restaurants are more than just their primary sources of livelihood. We argue that they approximate Soja’s “thirdspaces” (1996), which on the one hand mediate their interactions with the city and its other residents, and on the other hand mediate relationships between humans in the earthly world and deities in the “other” parallel world.