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1.
Summary Ready‐to‐eat breakfast cereals immersed in milk undergo undesirable changes in texture because of sudden moisture uptake. The textural changes are ascribable to a plasticizing effect of water, which modifies the mechanical strength of products by softening the starch/protein matrix. In this work, some textural parameters of different cereal flakes were derived from the force–displacement curves monitored during 300 s of immersion in milk. Hardness loss, deformability increment and changes in the force–displacement curve profile were calculated and plotted against soaking time. The application of a sugar coating process to a model cereal flake increased the initial product hardness and improved the preservation of the textural parameters during immersion. The Peleg model closely fitted the experimental data, with regression coefficients from 0.967 to 0.999.  相似文献   
2.
An application of Narrative Knowledge Representation Language (NKRL) techniques on (declassified) ‘terrorism in Southern Philippines’ documents has been carried out in the context of the IST Parmenides project. This paper describes some aspects of this work: it is our belief, in fact, that the Knowledge Representation techniques and the Intelligent Information Retrieval tools used in this experiment can be of some interest also in an ‘Ontological Modelling of Legal Events and Legal Reasoning’ context.  相似文献   
3.
Large eddy simulation of the free-shear flows has been performed using an algebraic subgrid stress model. The test cases considered are the temporal planar jet and mixing layer. The results are compared with that of the Smagorinsky, dynamic Smagorinsky, mixed models and the DNS data. For the mean flow quantities none of the models perform exceptionally better over the others. However, both the algebraic and mixed models predict better statistics for the turbulent quantities than the linear models. The results also demonstrate the capability of the algebraic model in depicting backscatter of energy explicitly, which is consistent in both the cases considered.  相似文献   
4.
The counter current heat exchanger theory with periodic inlet temperatures has been applied to analyze the thermal performance of a water heating system. The theoretical results obtained are in agreement with the experimental data reported in the literature.  相似文献   
5.
The definite trend towards the use of large-diameter rebars and the introduction of high-strength steels (f y=500 to 600 MPa) make it necessary to study the effects of longitudinal splitting on the steel-to-concrete bond. The study of splitting effects requires firstly basic tests to be performed in order to gather experimental information on bond and confinement stresses acting at the bar-to-concrete interface. For this purpose, three series of tests were recently carried out at the Politecnico di Milano. The results make it possible to ascertain a few basic properties of the bond after concrete splitting, and to formulate empirical constitutive laws regarding the stresses and the displacements (bar slip and opening of the splitting crack). All specimens consisted of a short deformed bar embedded in a concrete block, which had a preformed splitting crack in the plane passing through the bar axis: twelve specimens (Tests A and C) were fitted up with a round deformed bar having crescent-shaped lugs (Db=18 mm); seven specimens (Tests B) were fitted up with a specially machined deformed bar having a rectangular cross-section and straigth, lugs, so that concrete deterioration close to the bar could be investigated at the surface of the specimen, by means of the moiré technique. The tests were carried out at constant slip rate, up to very large slip values ( ); both the ascending and the descending branches of the stress-slip curves were measured, for four different values of the opening of the splitting crack. The agreement among the results of the three series is generally satisfactory and often very good: consequently, constitutive laws regarding the four main variables (crack opening and bar slip, shear and confinement stresses) can be worked out, as will be shown in a companion paper on constitutive relationships and on concrete deterioration at the bar-to-concrete interface.  相似文献   
6.
Interleukin (IL)-33 is a member of the interleukin (IL)-1 family of cytokines linked to the development of inflammatory conditions and cancer in the gastrointestinal tract. This study is designed to investigate whether IL-33 has a direct effect on human gastric epithelial cells (GES-1), the human gastric adenocarcinoma cell line (AGS), and the gastric carcinoma cell line (NCI-N87) by assessing its role in the regulation of cell proliferation, migration, cell cycle, and apoptosis. Cell cycle regulation was also determined in ex vivo gastric cancer samples obtained during endoscopy and surgical procedures. Cell lines and tissue samples underwent stimulation with rhIL-33. Proliferation was assessed by XTT and CFSE assays, migration by wound healing assay, and apoptosis by caspase 3/7 activity assay and annexin V assay. Cell cycle was analyzed by means of propidium iodine assay, and gene expression regulation was assessed by RT-PCR profiling. We found that IL-33 has an antiproliferative and proapoptotic effect on cancer cell lines, and it can stimulate proliferation and reduce apoptosis in normal epithelial cell lines. These effects were also confirmed by the analysis of cell cycle gene expression, which showed a reduced expression of pro-proliferative genes in cancer cells, particularly in genes involved in G0/G1 and G2/M checkpoints. These results were confirmed by gene expression analysis on bioptic and surgical specimens. The aforementioned results indicate that IL-33 may be involved in cell proliferation in an environment- and cell-type-dependent manner.  相似文献   
7.
Metallurgical and Materials Transactions A - A high $$\gamma ^{\prime }$$ volume fraction CoNi-base superalloy with roughly equal amounts of cobalt and nickel was successfully processed through...  相似文献   
8.
A theory has been proposed to evaluate the burning rate of a single carbon particle in a continuously operated coal-fired fluidized bed. Experimental verification was carried out in a laboratory scale 200 mm × 200 mm combustor. The burning rate increases with the increase of the fluidization velocity and the size of the bed material. The predicted data on burning rate agree fairly well with the experimental values. The gas concentration in the bed and freeboard has also been measured and it is seen that the consumption of oxygen mostly takes place in the bed.  相似文献   
9.
10.
Diatomite, a natural silicate-based sedimentary rock, was densified by cold sintering at room temperature and 150°C under various pressures (100, 200, and 300 MPa) and using different NaOH water solutions (0–3 M). The relative density of cold sintered diatomite can be as high as 90%, a condition that can be achieved by conventional firing only at 1200–1300°C. The cold sintered materials maintain the same mineralogical composition of the starting powder (quartz, glass, and illite) and are constituted by well-deformed and flattened grains oriented orthogonally to the applied pressure. Conversely, an evident phase evolution takes place upon conventional firing with the formation of cristobalite and mullite. The bending strength of cold sintered artifacts can exceed 40 MPa and increases to ≈80 MPa after post-annealing at 800°C, such mechanical strength is much larger than that of conventionally pressed samples sintered at 800°C, which is only ≈1 MPa.  相似文献   
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