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1.
Direct utilisation of biomass for energy application is less profound due to the problems of low calorific value, high water content, and low grindability of biomass. For this reason, pre-heating treatment, sometimes called torrefaction, is necessary to improve the physical properties of biomass similar to ‘coal-like’ material. Unfortunately, only few comprehensive but simple theoretical models focused on hard-wood biomass were available to describe the torrefaction process. In this discussion, a simple proposed torrefaction model was developed and reported. The model has ability to estimate the yield of product mass and energy after the torrefaction process and determine the optimum conditions.  相似文献   
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Inflammatory and immunogenic response to foreign bodies presents a challenge in the use of biomaterials as implants for tissue restoration. Therefore, there is a need to understand the interactions between such implants and the blood. One such material, currently in clinical use for bone replacement in humans, is the skeleton of corals, in the form of crystalline aragonite. This biomaterial has been shown to impart a protective and supportive influence on several types of cells ex vivo. The carbonate skeleton activates secretion in phagocytes in vitro, however its effects on these cells in the blood, and on the process of phagocytosis itself, remain unknown. Using 1–500 μm particles of coral skeleton, we show that these particles bind blood proteins and alter the leukocyte population, reducing the proportion of granulocytes by more than 3-fold with no effect on the proportion of monocytes. In addition, the presence of coral skeleton in the blood causes a reduction in phagocytosis. Specifically, we observed a decrease in the percentage of phagocytic cells by 27 % in the granulocytes and by 73 % in monocyte family, as well as a 41.6 % reduction in the MFI of granulocytes, but with no such effect on monocytes. Taken together, the results suggest that the coral skeleton biomaterial may act as a strong, promotive scaffold for tissue regeneration due to its ability to reduce its rejection by inflammatory reactions such as phagocytosis.  相似文献   
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Antimicrobial packaging can preserve and increase shelf life of free preservatives food products. Active materials present in the packaging material can migrate, in a controlled manner, to the food surface, avoiding bacterial and fungal proliferation and keeping the food product edible for longer periods of time. Essential oils (EO) are natural antimicrobial agents that can be released to the headspace with no direct contact between the package and the food. To minimize loses of EO during high heat melt processing, a three stages process was implemented and tested. Antimicrobial films were prepared by melt mixing a variety of polyethylene copolymers in the presence of organo‐modified montmorillonite nano clay (NC) and thymol, an EO present in oregano and thyme. A controlled EO desorption from films can be achieved by changing the polymer crystallinity and polarity. As the crystallinity increased, the thermal stability of the EO during the extrusion process improved. The addition of NC affects the structure and homogeneity of the crystals. The combination of high polymer crystallinity and chemical affinity between EO and NC increased the thermal stability of the EO during film processing, enabling to control the desorption rate. The effect of multilayer structure based on varied densities and polarities was also studied. Increasing the polarity of the outer layers in multilayered film reduced the EO desorption rate as a result of chemical interactions between the polymer and the EO. The final antimicrobial activity of the films was also found to be dependent on the EO partitioning. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40309.  相似文献   
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In the vegetable oil chemical industry, hydrogenation is one of the most important processes. An alternative method for vegetable oil hydrogenation is the use of catalytic transfer hydrogenation (CTH), which can utilize organic molecules as hydrogen donors at ambient pressure. These alternative processes should be optimized in relation to the variables required for a good conversion and impacts should also be known to be minimized. An assessment of the environmental impact of laboratory scale chemical processes is an important tool to improve the technological aspects of a process (increased yields, reduced production times, lower costs) and it can also lead to the creation of a cleaner technology. Using the Leopold Matrix, we have succeeded in developing a more efficient and cleaner process for the CTH of castor oil using Raney Ni as a catalyst and cyclohexene or isopropanol as a hydrogen donor solvent. The results of the technical and environmental assessments showed that the extent of conversion for the unsaturation reaction was high (>99 %), and the environmental impact of the process could be significantly reduced to create a cleaner technology. It was found, after process optimization, that the remaining environmental impacts were negative (67.48 %), local (78.95 %), temporary (95.33 %), direct (80.12 %), and reversible (95.32 %).  相似文献   
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The International Planning Competition is a biennial event organized in the context of the International Conference on Automated Planning and Scheduling. The 2008 competition included, for the first time, a learning track for comparing approaches for improving automated planners via learning. In this paper, we describe the structure of the learning track, the planning domains used for evaluation, the participating systems, the results, and our observations. Towards supporting the goal of domain-independent learning, one of the key features of the competition was to disallow any code changes or parameter tweaks after the training domains were revealed to the participants. The competition results show that at this stage no learning for planning system outperforms state-of-the-art planners in a domain independent manner across a wide range of domains. However, they appear to be close to providing such performance. Evaluating learning for planning systems in a blind competition raises important questions concerning criteria that should be taken into account in future competitions.  相似文献   
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Reviews the book, Creative leadership: Skills that drive change by Gerard J. Puccio, Mary C. Murdock, and Marie Mance (2007). The introduction and opening chapter provide the overarching theme of the book, which is to connect the constructs of creativity and leadership and to make a case why the two go hand-in-hand. Both constructs involve dealing with change. The main focus of the book is the creative problem solving (CPS) approach to generating optimal problem solutions. Much of the book is spent illustrating the benefits of applying divergent and convergent thinking skills to each of the six process steps in the CPS model. The book is an easy, enjoyable read with plenty of empirical support for many of the propositions and tenets put forth. Puccio, Murdock, and Mance do a good job of pointing out that creative leadership is not just for the chosen few, but rather can be practiced by anyone. Plenty of practical advice is offered with numerous real-world examples. The book is a good choice even for individuals without any formal education in creativity or leadership. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
Many cognitive process theories of creativity include an initial process of problem identification, definition, and construction. Previous research suggests that problem identification and construction is related to creativity, and that creative individuals and experts tend to engage in problem identification and construction. Finally, previous research suggests that inducing active engagement in problem identification and construction, through instructions or training, facilitates creativity. The authors offer views regarding important future direction for researchers in this area. Specifically, issues regarding methodology, the relationship between personality and values and how problems are constructed, and problem identification and construction in teams are suggested as important avenues for future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
This study addresses the issue of domain specificity within creativity by understanding the characteristics of creative tasks and how participants react to the task. Participants (N = 187) were given 1 of 3 realistic everyday problems to solve. The problems differed in terms of complexity, involvement, and problem-based efficacy. Problem solutions were evaluated on several measures of creativity. Results indicate that creativity was influenced by the type of problem solved and the measure of creativity used to evaluate the solution. Furthermore, these results were obtained after controlling for the effect of ability. Results imply that not all real-world problems are equivalent and that researchers need to investigate how reactions to different problems and the creativity index used may influence conclusions regarding creative problem solving. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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