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1.
Chlorogenic acid at 5° published threshold concentration (100 mg/ L) in aqueous 0.2% potassium acid tartrate was not significantly more bitter than aqueous 0.2% potassium tartrate alone when evaluated by taste panel. 相似文献
2.
L. ALBERTO MOSQUERA CHARLES A. SIMS ROBERT P. BATES SEAN F. O'KEEFE 《Journal of food science》1996,61(4):856-861
Horchata is a sweetened water extract of chufa tubers (Cyperus esculentus) which is very popular in Spain, and has potential in the U.S. The objectives of this research were to characterize horchatas from different types of chufa, and to monitor flavor and stability of unheated and pasteurized horchatas during storage (2°C). Trained panelists rated the following attributes: color, chalkiness, sweetness, vanilla-like, nutty, earthiness, bitterness, and off-flavor. Horchatas made with chufa grown in Spain and chufa from Spain but grown in Florida showed higher vanilla and nutty levels than horchata from the Florida type. During storage (2°C), vanilla, nutty, and sweetness decreased, and other attributes increased. Heating to 70 and 95°C for 1 min did not alter sensory attributes initially, prevented off-flavor development, and slowed changes in desirable attributes for 35 days. 相似文献
3.
CHARLES A. SORRELL 《Journal of the American Ceramic Society》1977,60(5-6):217-220
Solutions of ZnCl2 were prepared from ZnCl2 · n H2 O and by reaction of zinc metal with HCl. Specific gravities and pH values were determined as a function of composition. A ternary phase, 4ZnO·ZnCl2 ·5H2 O, was precipitated when the ZnCl2 solutions were diluted to a pH of 5.48 ± 0.05. Mixtures of ZnO with ZnCl, and HCI solutions were equilibrated in sealed containers and analyzed by X-ray diffraction. The resulting phase diagram shows 2 ternary phases, 4ZnO·ZnCl2 ·5H2 O (4·1·5) and ZnO·ZnCl2 ·2H2 O (1.1.2), both of which are soluble to the extent of < 1 wt% in ZnCl2 solutions. Thermogravimetric data indicate that the 1.1.2 phase loses half the constituent H2 O at ∼230°C and the remainder, with ZnCl2 , at higher temperatures. The 4.1.5 phase dissociates to ZnO and 1.1.2 at ∼160°C. The system ZnCl2 -H2 O is not binary, but is a section through the ternary system ZnO-HCl-H2 O, with the solubility curve of the 4.1.5 phase intersecting the ZnCl2 -H2 O section in dilute solutions. 相似文献
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CHARLES A. SORRELL 《Journal of the American Ceramic Society》1971,54(10):501-503
Thermal expansion of Pb3 O4 was investigated by high-temperature X-ray diffraction. The coefficient in the a 0 direction is 14.6×10−6 /°C. Expansion in the c0 direction is 32% greater, with a coefficient of 19.3×10−6 /°C. Coefficients of expansion are linear from 25° to 490°C and are comparable with those of tetragonal and orthorhombic PbO. 相似文献
8.
The control design of systems with lightly damped high frequency oscillatory modes is treated. Systems exhibiting these lightly damped modes include turbine generators and large flexible structures. Frequently the dynamics of these high-frequency modes are not known very accurately. As a result, the design objective is to improve the slow dynamics without destabilizing the high-frequency modes. From a classical frequency domain design viewpoint, this is in part a filtering problem requiring some kind of high-frequency filter. The singular perturbation method is used to systematically develop a two-time-scale method to design these high-frequency filters and provides guidelines on the kind of high-frequency filter to be used. In addition, the method provides an asymptotic error analysis. The design is illustrated with an example representative of a power system model with a two-mass turbine-generator model. 相似文献
9.
CHARLES H. SMITH 《国际通用系统杂志》2013,42(4):385-400
The emphasis in this work is on the practical application of ideas set forth in Part I. Two studies involving spatial distribution are discussed: the distribution of human population in the Indianapolis, Indiana Region, and the world distribution of mammals. In the first, populations over the period 1890–1980 of Ihe 393 townships making up the study area are used to produce classifications involving various numbers of classes of township types. A test of the theoretical structure posed in Part I is then detailed. On the theory that the underlying relations involved cannot sustain a real world structure involving more than five functional classes, it is hypothesized that classifications involving more than five classes will be associated with township distribution patterns that conflict with Central Place Theory. This is shown to be clearly so. In the second study, the derivation of a five region partitioning of world mammalian distribution patterns is described. Discussion includes the introduction of a wholly new rationale for taxonomic revision based on biogeographic criteria (and ultimately the principles described in Part I). The study closes with a short argument regarding why the model described in Part I should not be labelled as either social physics or anti-humanistic. 相似文献
10.
The precepts behind the macroscopic and microscopic quantizations of the electromagnetic field in a dielectric are discussed. Using the correspondence principle, it is demonstrated that the macroscopic quantization procedure leads to incorrect equations of motion of embedded two-level atoms. The fundamental nature of the Lorentz viewpoint of electrodynamics is discussed. 相似文献