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91.
This paper presents a simulation study of dryers. A two-dimensional deep-bed drying model, which incorporates modifications in existing one-dimensional models, has been developed and has the capability of handling both non-uniform velocity profiles and material properties dependence on temperature and moisture content. A corn drying system was simulated in order to analyze its temporal and spatial drying behavior. Both intermittent and continuous drying were simulated. The results showed that continuous drying is more efficient than intermittent drying with respect to drying time. However, intermittent drying led to more uniform temperature and moisture distributions, which improve grain quality. The model can be easily extended to three-dimensional drying analysis.  相似文献   
92.
Abstract The key research question in this small‐scale study focuses on the effects that an ICT (information and communications technologies)‐based concept mapping intervention has on creativity and writing achievement in 10–11‐year‐old primary age pupils. The data shows that pupils using a concept mapping intervention significantly improve their NFER non‐verbal reasoning age‐standardised scores over a control group with a higher baseline whose scores remain constant. Evidence linking this with using ICT‐based concept mapping remains inconclusive. Correlation studies show that writing achievement and creativity are linked and that writing achievement and concept mapping connectivity are linked. However, there is no conclusive evidence for linking concept mapping connectivity with creativity. Findings show that concept mapping components increase post‐test and that concept mapping ability can be evaluated using a connectivity index that may have some predictive value in assessing writing achievement. The findings suggest that ICT‐based concept mapping provides a reliable framework from which to structure writing and that ICT enhances learning and use of this representational technique and provides opportunities for developing innovative and educationally valid practices.  相似文献   
93.
Let C be the binary narrow-sense BCH code of length where m is the order of 2 modulo n. Using characters of finite fields and a theorem of Weil, and results of Vladut-Skorobogatov and Lang-Weil we prove that the code C is normal in the non-primitive case if and in the primitive case if where the constant depends only on t. Received January 4, 1994  相似文献   
94.
OBJECTIVE: To define the mechanisms of action of 2 novel drugs, cyclosporine and anti-tumor necrosis factor alpha (TNFalpha), in collagen-induced arthritis and to determine the effect of combination therapy. METHODS: Type II collagen-immunized DBA/1 mice with established arthritis were treated with cyclosporine alone, anti-TNFalpha alone, cyclosporine plus anti-TNFalpha, or saline. RESULTS: Cyclosporine was found to ameliorate arthritis, suppress interferon-gamma (IFNgamma) production by CD4+ T cells, and reduce TNFalpha expression in arthritic joints. However, cyclosporine did not directly inhibit TNFalpha production by macrophages, indicating that the decrease in TNFalpha expression observed in vivo was probably an indirect consequence of the reduction in type 1 T helper cell activity. Anti-TNFalpha also reduced IFNgamma production by T cells, indicating that TNFalpha is involved in the cellular immune response to collagen. Combined treatment with cyclosporine plus anti-TNFalpha had an additive therapeutic effect. CONCLUSION: Although cyclosporine and anti-TNFalpha target different points in the inflammatory pathway, there is an overlap in the consequences of their actions in vivo.  相似文献   
95.
The authors present the basic features of a specification language for concurrent distributed systems, developed at the Department of Information Sciences of the University of Milan, Italy. The language is based on a class of modular algebraic high-level nets, OBJSA nets, which result from the synthesis of superposed automata (SA) nets and of the algebraic specification language OBJ. It is supported by the OBJSA Net Environment (ONE). OBJSA nets stress the possibility of building the system model by composing its components and encourage the incremental development of the specification and its reusability. An OBJSA net consists of an SA net inscribed with terms of an OBJ module. The ONE environment supports the user in producing and executing a specification, hiding from her/him, as much as possible, the technical details of the algebraic part of the specification. The paper provides a complete presentation of OBJSA nets, including a user-oriented introduction, the definition of OBJSA nets (as subclass of SPEC-inscribed nets), of their occurrence rule (the semantics) and of the composition operation. In addition it presents the kernel of the support environment  相似文献   
96.
97.
The lacrimal film has attracted increasing interest in the last decades as a potential source of biomarkers of physiopathological states, due to its accessibility, moderate complexity, and responsiveness to ocular and systemic diseases. High-performance liquid chromatography-mass spectrometry (LC-MS) has led to effective approaches to tear proteomics, despite the intrinsic limitations in sample amounts. This review focuses on the recent progress in strategy and technology, with an emphasis on the potential for personalized medicine. After an introduction on lacrimal-film composition, examples of applications to biomarker discovery are discussed, comparing approaches based on pooled-sample and single-tear analysis. Then, the most critical steps of the experimental pipeline, that is, tear collection, sample fractionation, and LC-MS implementation, are discussed with reference to proteome-coverage optimization. Advantages and challenges of the alternative procedures are highlighted. Despite the still limited number of studies, tear quantitative proteomics, including single-tear investigation, could offer unique contributions to the identification of low-invasiveness, sustained-accessibility biomarkers, and to the development of personalized approaches to therapy and diagnosis.  相似文献   
98.
The usefulness of amaranth protein isolates, native and thermally treated, in edible films preparation was studied. Protein films were prepared by casting using glycerol as plasticizer. Films from amaranth native protein isolates showed low water vapor permeability (WVP) but poor mechanical properties. In order to improve this functionality, proteins were treated at 70 and 90 °C which corresponds to the denaturation temperature of the protein fractions present in the isolates. The unfolded conformation of these thermally treated proteins, when partially or totally denatured, favors the interactions between polypeptide chains during the film formation. These interactions lead to a greater cross-linking degree, which was reflected in the lower amount of water-soluble free peptides that were linked to the matrix. In these thermally treated protein films, a greatest contribution of disulfide and hydrogen bonds to the films stabilization was observed. These changes in the films structural properties would confer them a greater tensile strength and lower water solubility but higher thickness and WVP.  相似文献   
99.
In this work we study the behavior of the optical phonon modes in bilayer graphene devices by applying top gate voltage, using Raman scattering. We observe the splitting of the Raman G band as we tune the Fermi level of the sample, which is explained in terms of mixing of the Raman (Eg) and infrared (Eu) phonon modes, due to different doping in the two layers. We theoretically analyze our data in terms of the bilayer graphene phonon self-energy which includes non-homogeneous charge carrier doping between the graphene layers. We show that the comparison between the experiment and theoretical model not only gives information about the total charge concentration in the bilayer graphene device, but also allows to separately quantify the amount of unintentional charge coming from the top and the bottom of the system, and therefore to characterize the intrinsic charges of bilayer graphene with its surrounding environment.  相似文献   
100.
In this study, removal of suspended solids (SS) and turbidity from marble processing wastewaters by electrocoagulation (EC) process were investigated by using aluminium (Al) and iron (Fe) electrodes which were run in serial and parallel connection systems. To remove these pollutants from the marble processing wastewater, an EC reactor including monopolar electrodes (Al/Fe) in parallel and serial connection system, was utilized. Optimization of differential operation parameters such as pH, current density, and electrolysis time on SS and turbidity removal were determined in this way. EC process with monopolar Al electrodes in parallel and serial connections carried out at the optimum conditions where the pH value was 9, current density was approximately 15 A/m2, and electrolysis time was 2 min resulted in 100% SS removal. Removal efficiencies of EC process for SS with monopolar Fe electrodes in parallel and serial connection were found to be 99.86% and 99.94%, respectively. Optimum parameters for monopolar Fe electrodes in both of the connection types were found to be for pH value as 8, for electrolysis time as 2 min. The optimum current density value for Fe electrodes used in serial and parallel connections was also obtained at 10 and 20 A/m2, respectively. Based on the results obtained, it was found that EC process running with each type of the electrodes and the connections was highly effective for the removal of SS and turbidity from marble processing wastewaters, and that operating costs with monopolar Al electrodes in parallel connection were the cheapest than that of the serial connection and all the configurations for Fe electrode.  相似文献   
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