Composition effects of thermal barrier coating ceramics on their interaction with molten Ca–Mg–Al–silicate (CMAS) glass

Systematic studies have been performed to investigate the composition effects of ZrO₂-based thermal barrier coating (TBC) ceramics on their interactions with molten Ca–Mg–Al–silicate (CMAS) glass. Porous ceramic pellets (～15% porosity), instead of actual TBCs, are used in these model studies, where the penetration of molten CMAS into the pellets is investigated. This study involves a total of six compositions of ZrO₂-based ceramics: two containing low solute (Y³⁺ or Gd³⁺) concentration, three with high concentration of solute (Y³⁺, Gd³⁺ or Yb³⁺), and one containing a combined intermediate concentration of Y³⁺+Al³⁺+Ti⁴⁺ solutes. While both the type of the solute and its concentration in the ZrO₂-based TBC ceramics have been found to influence the extent of molten CMAS penetration into the pellets, the solute concentration has the most dramatic effect. In particular, molten CMAS penetration is almost completely suppressed in porous TBC ceramic pellets containing a high concentration of Y³⁺ solute (Y₂Zr₂O₇). Possible mechanisms governing these effects are presented, together with a discussion of guidelines for the chemical design of CMAS-resistant zirconate TBC ceramics. Generally, for a TBC ceramic to be highly effective against CMAS attack it must interact vigorously with the molten CMAS, which must result in the rapid crystallization of the refractory oxide phase(s) that form a sealing layer, arresting further penetration of the molten CMAS. The porous ceramic pellets approach used here could be developed into rapid-screening methodologies for the discovery of CMAS-resistant TBC ceramic compositions, and to study the effect of composition of CMAS glasses on their interactions with TBC ceramics of specific compositions.     

The analytic network process for managing inter-enterprise collaboration: A case study in a collaborative enterprise network

In the last years, collaboration among enterprises has gained attention in the business environment as a means to remain competitive. Enterprises that are collaborating look for improving their performance but, in real assessments, they often do not establish efficient frameworks to structure and manage the enterprise association/inter-enterprise performance. In addition, there are many factors that act as barriers to effective collaboration and have to be also properly managed as they impact on the inter-enterprise performance. This paper provides a methodology based on the analytic network process (ANP) to identify and measure, under an integrated approach, both factors and inter-enterprise performance considering their reciprocal impact. With this innovative approach, enterprises will obtain significant information for the decision-making process regarding which are the factors and inter-enterprise performance elements that generate a higher impact and therefore have a high priority within the specific collaborative relationship. Thus, enterprises can focus their efforts on improving those most important factors and performance elements, and consequently, enhancing their competitiveness.     

Application of ergothioneine-rich extract from an edible mushroom Flammulina velutipes for melanosis prevention in shrimp,Penaeus monodon and Litopenaeus vannamei

This report investigated the melanosis-inhibiting properties of crude water soluble extract from the base and fruiting body waste of an edible mushroom (Flammulina velutipes) containing 9.13 ± 2.03 mg/mL 2-thiol-l-histidine-betaine (ergothioneine, ESH). Immersion of live full-grown black tiger shrimp (Penaeus monodon) and Pacific white shrimp (Litopenaeus vannamei) in a 0.5% w/v solution of mushroom extract for 1 h significantly decreased polyphenoloxidase (PPO) activity in shrimp hemolymph and expression of the prophenoloxidase (proPO) gene in hemocytes. Consequently, the development of melanosis in the treated shrimp during ice storage was prevented. Treatment with a 0.05% w/v solution of sodium sulfite and 4-hexyl-1,3-benzenediol had a similar effect. Enzyme assays showed that ESH is a non-competitive inhibitor. It is proposed that ESH possibly interacts directly with Cu²⁺ at the putative binding sites of PPO and proPO, based on copper-chelating activity analyses, thus preventing melanosis in the shrimp. This study indicated that application of ESH-rich F. velutipes mushroom extract from trimming waste is an effective natural alternative to synthetic melanosis-inhibiting agents to prevent postmortem melanosis in shrimp.     

Relating TQM,marketing and business performance: An exploratory study

Total Quality Management (TQM) is perhaps the leading management approach that companies employ to improve their product and service quality with the aim of improving typical measures of business performance (e.g. increased profits, increased market share, reduced costs). However, consumer perception of quality not only results from an evaluation of the intrinsic quality attributes of the product (e.g. performance, reliability, durability) but is also affected by the marketing mix (e.g. price, advertising, warranties) adopted by the company selling the product. This paper offers a first attempt at cross-functional fertilization by examining the relationships between TQM, some marketing mix variables and measures of company performance by exploring the diverse multidisciplinary literature and developing an explanatory framework, which is tested using non-parametric correlation and refined through an empirical study of Spanish manufacturing companies. The results show that the most important TQM dimensions are the system of employee relations and the use of quality management-related design tools. The results also indicate the existence of a relationship amongst price, advertising and warranties, but that these marketing variables were not related to TQM and that further research is required to include a wider definition of marketing strategy.     

Neural and Neural Gray-Box Modeling for Entry Temperature Prediction in a Hot Strip Mill

In hot strip mills, initial controller set points have to be calculated before the steel bar enters the mill. Calculations rely on the good knowledge of rolling variables. Measurements are available only after the bar has entered the mill, and therefore they have to be estimated. Estimation of process variables, particularly that of temperature, is of crucial importance for the bar front section to fulfill quality requirements, and the same must be performed in the shortest possible time to preserve heat. Currently, temperature estimation is performed by physical modeling; however, it is highly affected by measurement uncertainties, variations in the incoming bar conditions, and final product changes. In order to overcome these problems, artificial intelligence techniques such as artificial neural networks and fuzzy logic have been proposed. In this article, neural network-based systems, including neural-based Gray-Box models, are applied to estimate scale breaker entry temperature, given its importance, and their performance is compared to that of the physical model used in plant. Several neural systems and several neural-based Gray-Box models are designed and tested with real data. Taking advantage of the flexibility of neural networks for input incorporation, several factors which are believed to have influence on the process are also tested. The systems proposed in this study were proven to have better performance indexes and hence better prediction capabilities than the physical models currently used in plant.     

Occurrence of C16:1 isomers in milk fats from ewes fed with different dietary lipid supplements

The trans as well as the cis C16:1 isomer profiles were established in 43 ewe milk fats supplemented with different dietary lipid sources representative of the variety of unsaturated fatty acids found in nature such as olive, sunflower, linseed and fish oils. Fractionation by silver-ion solid phase extraction facilitated a rapid separation of the trans, cis and saturated FA before gas chromatography analysis took place. C16:1 isomers with a double bond in positions 7, 9 and 13 in the cis group and 8 and 9 in the trans fraction were the most abundant. Dietary lipid supplementation produced a noticeable increase in the total trans C16:1 content and elevated correlations were observed between trans-8 C16:1 and trans-10 C18:1 as well as trans-9 C16:1 and trans-11 C18:1. These results support the idea that altering the trans C18:1 profile affects trans C16:1 isomer composition consistent with the β-oxidation products from the trans C18:1 isomers.