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A mathematical model of kinetics of carbide layer formed on the surface of steel in fused system was set up with the theory of non-stable diffusion mass transfer and regular solution sub-lattice. This model was analyzed and testified by the experiments in which the VC layers were formed on four kinds of steels as steel 45, 4Cr5Mo-SiV1, T10, and Crl2MoV immersed in the V2O5-Na2O-B2O5 fused system with the reducing agent of silicon. The results showed that there was a good agreement between the model and the experimental results; the growth speed of carbide layer depended on the factors of carbon activity in substrate, treatment temperature, kinds of carbides and its structure
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TEM in situ tensile tests of 310 stainless steel show that a dislocation free zone (DFZ) forms if the displacement keeps constant after dislocations are emitted from a crack tip. The elastic DFZ is gradually thinned and the stress in the DFZ will reach the cohesive strength, resulting in nucleation of nanocracks in it and their bluntness into voids. If continuously tensioning, the inhomogeneously thinning ahead of the crack tip, initiat-ing and connecting of microcracks or microvoids will be observed rather than a DFZ, nanocracks' initiation and bluntness into voids. The inverse pile-up ahead of a loaded crack tip can move back to the crack tip when unloading
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The effects of different firing temperatures on the stability of perovskite phase, grain size, and dielectric properties were investigated by XRD, TEM, SEM and dielectric measurements. The dielectric ceramics of Pb(Mg1/3Nb2/3)O3-PbTiO3-BaTiO3 system were obtained by chemical coprecipitation in water. The ceramics have higher dielectric constant (7003-9714), lower firing temperature (950-1150℃), quite uniform microstructure with grain size less than 2.5μm, and lower temperature coefficients of capacitance. As a result, it was confirmed that the simple and low cost chemical route used namely coprecipitation in water is a desired meth-od for preparing high property dielectric materials applicable to multilayer capacitors
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During recent years there has been an explosive growth in the market for fresh prepared fruit and vegetable (i.e. produceproducts. The main driving force for this market growth is the increasing consumer demand for fresh, healthy, convenient and additive-free prepared product items. However, fresh prepared produce items are highly perishable and prone to the major spoilage mechanisms of enzymic discoloration, moisture loss and microbial growth. Good manufacturing and handling practices along with the appropriate use of modified atmosphere packaging(mp)are relatively effective at inhibiting
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After comparing the sensitizing effect of various mixed surfactants on the chromophoric reaction of gallium (Ⅱ) with orthochlorophenylf luorone, it has been found that the mixed micelle of cetyltrimethylammonium bromide and Tween-80 is most suitable. In the presence of this mixed micelle, not only both the sensitivity and stability improve markedly, but also a wider pH range is tolerable for the colour-development. From the study on the optimum conditions for the formation of the coloured coordination compoundin the system of 《Ga (Ⅱ)——o-Chlorophenyl fluorone-catyltrimethylammo-nium bromide——Tween-80》 and its main characters, a spectrophotometricmethod, by which sensitivity and reproducibility are higher than those of ternary systems of gallium(Ⅱ) has been developed. When it is combined with the dual-wavelength method, the molar absorptivity can be improved to 2.33×105 l·mol-1·cm-1,which is higher than that of most of other systems ever sh
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Interactions within a package system refer to the exchange of mass and energy between the packaged food, the packaging material and the external environment. Food-packaging interactions can be defined as an interplay between food, packaging, and the environment, which produces an effect on the food, and/or package (Hotchkiss, 1997). Mass transfer processes in packaging systems are normally referred to as permeation, migration and absorption(fig8.1). Permeation is the process resulting from two basic mechanisms
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The optimum conditions for extraction chromatography using 2ethyl-hexyl 2-ethylhexylphosphonate resin to separate thulium, yetterbium and luticium were studied. According to the proposed procedure, several grams of yetterbium oxide (purity = 99.95%) and luticium oxide (purity = 99.90%) were separated from the mixed heavy rare earth oxides on laboratory scale. Their relatively high recoveries (99% and 95% for Yb2O3 and Lu2O3 respectively) may be satisfactory
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SUPPLY CHAIN VISIONS LOGISTICS TERMS and GLOSSARY Updated October 2003 ABB: See Activity Based Budgeting ABC: See Activity Based Costing ABC Classification: Classification of a group of items in decreasing order of annual dollar volume or other criteria. This array is then split into three classes called A, B, and C. The A group represents 10-20% by number of items and 50-70% by projected dollar volume. The next grouping, B, represents about 20% of the items and about 20% of the dollar volume. The
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Equilibrium between slag and molten iron at 1600℃ was investigated for the direct alloying of steel with Nb2O6-bearing slag. The activity of niobium oxide in the slag was measured. The αNb2O5 is in the range of 10-2-10-4. TheδNb2O5 is ranged in 100-10-2.Niobium partition decreases with the increase of[Si]% and CaO/SiO2. When α[0] and ΣFeO decrease, niobium partition decreases too. The δNb2o5 and the ratio of γsiO2 to γNb2O5 decrease with the incre-ase of slag basicity. The suitable thermodynamic conditions in direct alloying of steel with Nb2O5-bearing slag have been found
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October 22, 2001 Personal IdentityⅢ . Review soul criterion and body criterion Soul criterion: x is the same person as y iff and y have the same soul. Problems: i)There is no way to establish body-soul correlations; and no way to establish personality correlations. So soul criterion doesn't make sense of our practices of recognizing and identifying people ii)We have no special access to souls, so even in our own case we can't be sure it's the same soul \inside\ us whenever we are conscious. ii) The problem of identity is \pushed back\: what is it for person-stage x to have the same soul as person-stage y? What makes for sameness of souls? Body criterion: x is the same person as y iff x and y have the same living human body
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