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121.
The dietary potential of the common nettle 总被引:1,自引:0,他引:1
R E Hughes P Ellery T Harry V Jenkins E Jones 《Journal of the science of food and agriculture》1980,31(12):1279-1286
A leaf protein concentrate prepared from the young leaves of the common nettle (Urtica dioica) failed to support normal growth in young rats; supplementation with methionine produced a protein efficiency ratio greater than that of casein. A nettle leaf wholemeal, providing 66% of the dietary protein, supported normal growth in young guinea-pigs, mice and rats. Chicks receiving the whole nettle meal as their sole dietary protein grew at only half the rate of chicks given a standard commercial diet. A nettle meal-induced hypercholesterolaemia in mature guinea-pigs and kidney hypertrophy in mice and guinea-pigs should perhaps be interpreted as a caution against the indiscriminate introduction of nettles into the human diet. 相似文献
122.
Larry J. Darlage Harry N. Finkbone Samuel J. King Jitendra Ghosal Maurice E. Bailey 《Fuel》1978,57(8):479-484
A series of 34 nitrogen-containing compounds with a wide range of basicities was examined under differential nonaqueous potentiometric conditions in acetophenone and nitrobenzene. These compounds could be resolved into five classes based on pKaand half-neutralization-potential (HNP) values. Asphaltenes isolated from the vacuum still overhead (VSO) and vacuum still bottoms (VSB) fractions of the H-coal process were titrated under similar conditions. The titration results of both asphaltenes indicated the presence of two classes of nitrogen-containing compounds, a titratable class of the pyridine-ring or aniline type and a nontitratable class. 相似文献
123.
Elasto-plastic wave propagation in a one dimensional rod is treated by utilizing finite element analysis. The time dependence is handled by means of a variable time step numerical integration method. Elasto-plastic reflections from a fixed boundary and interaction of plastic waves are discussed.
Theoretical expressions are presented for determining the stress response for a material exhibiting bilinear hardening behavior during elasto-plastic wave interaction and boundary reflection. These expressions are employed to evaluate predictions made by the numerical procedure.
In the computations, steep wave fronts are approximated by ramps. The steepness of these ramps may be increased by refining the finite element grid. Excellent agreement is obtained between numerical and theoretical elastic and inelastic stress response levels. 相似文献
124.
Schlosberg's dimensional theory of emotion, including the dimension of tension-sleep, is tested to compare results obtained previously with American college students with those obtained in this study using Greek Ss. 15 Greek villagers and 15 college students in Athens comprised the 2 experimental groups which differed from each other in educational level and in lifetime movie attendance. The data indicate that Schlosberg's conclusions are now valid for non-Western groups as well as Western. Furthermore an emotion solid can be plotted from data collected by making use of Schlosberg's procedure, but the shape of the solid is not the same as that previously presented by Schlosberg. 18 references. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
125.
The Likens-Nickerson concurrent steam distillation-solvent extraction apparatus was used to obtain an essence from malt extract. The essence was submitted to combined gas chromatography-mass spectrometry (g.c.-m.s.), to examination by sulphurspecific and nitrogen-specific detectors, and to sensory evaluation of the components eluted from gas chromatographic capillary columns. Some 33 compounds were identified by direct examination by g.c.-m.s., another 14 by trapping and re-injection, which provides an efficient method of concentration, and a further six, which had not been previously identified due to interference from the solvent peak, by the use of charcoal adsorption traps. Results indicate that several compounds need to be combined to simulate malt flavour. The odour contributions of several components are discussed. 相似文献
126.
X-ray photoelectron spectroscopy was used to measure binding energies of S 2p electrons of sulphur in S-trithiane, and in anisotropic carbon (heat-treatment temperature 873 K) formed from S-trithiane and from a humic acid derived from a Polish brown coal. A satisfactory technique is to prepare the specimens as a thin film on a gold plate. In all these materials, the sulphur atom environments are identical, corresponding to heterocyclic sulphur, 163.3 eV binding energy. Experimental binding energies are compared with those obtained using a charge-potential model from CNDO orbital calculations. 相似文献
127.
The construct validity and developmental structure of R. A. Hogan's (see record 1966-00843-001) model of counselor development and supervision were studied using a sample of 141 counseling psychology graduate student trainees, interns, and professional staff in 20 university counseling centers. Counselor development questionnaire items were developed into 2 arrangements: one based on Hogan's concepts as he organized them into levels, and another derived empirically using factor analysis. The 2 configurations were compared for their ability to predict experience level of Ss using discriminant function analysis. Each empirical factor was also examined for relationship with experience by means of 1-way ANOVA with preplanned comparisons. Results indicate that counselor development is best described by a complex rather than a simple model and that it involves factors of Anxiety/Doubt, Independence, Method/Skills Training, Work Validation, Commitment Ambivalence, and Respectful Confrontation. Developmental profiles of these issues are described, and implications for supervision and training programs are discussed. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
128.
129.
Tiersten HF 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2003,50(11):1436-1443
A modal representation of the thickness vibrations of rotated Y-cut quartz plates, which was used in the treatment of driven transversely varying thickness modes, is shown to be defective in certain respects. The differential equations and edge conditions for transversely varying thickness modes have been used in the accurate treatment of trapped energy resonators, monolithic crystal filters, and contoured quartz resonators, even though those defects were present. In this work those defects in the thickness solution are corrected along with the influence on the differential equations and edge conditions in the transversely varying case. The corrected modal representation shows that, because in practical applications to the above mentioned devices, the driving frequency is always near a thickness resonant frequency, essentially the same results will be obtained with the corrected representation as were obtained with the defective one, which explains why the results obtained with the defective equations were so accurate. 相似文献
130.
Loffler G Orbach HS 《Journal of the Optical Society of America. A, Optics, image science, and vision》2003,20(8):1461-1471
The perceived direction of motion of a featureless contour inside a circular aperture is always perpendicular to the contour's orientation, regardless of its true motion (the aperture problem). This study investigates the circumstances under which unambiguous feature motion (of line terminators, single dots, or truncations of a D6 pattern) in adjacent apertures can alter the perceived direction of such featureless contours. We find that integration mechanisms responsible for motion capture are fairly robust against misorientations and contrast manipulations of individual components, are sensitive to differences in spatial frequencies, and scale with pattern size. Motion capture is not diminished when a D6 profile is substituted for the square-pulse profile of a line and is independent of the visibility of the apertures, indicating that object interpretations and three-dimensional analyses of a scene are less important than has been postulated previously. These results have strong implications for the neuronal hardware underlying the integration of motion signals across space and provide a framework for global motion models. 相似文献