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921.
One reason for the limited attention to existential psychology in child treatment is the assumption that children are restricted in the amount of freedom and responsibility they can assume. However, current research on child development reveals that children actively influence their social and physical environment and hence begin from birth the process of self-determination. This article presents guidelines for implementing existential psychology with children derived from theoretical tenets and case study findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
922.
S A Brantmeier M E Bellin S K Boehm S M Bushmeyer C L Kubajak M R Dentine R R Grummer R L Ax 《Journal of dairy science》1987,70(10):2138-2144
Concentrations of estradiol-17 beta in follicular fluid were correlated to follicular size, stage of estrous cycle, location of corpus luteum, and presence of large follicles. Paired ovaries were obtained from 481 nonpregnant cows at slaughter and follicles were classified as ipsilateral or contralateral to the corpus luteum. Follicular fluid estradiol-17 beta concentrations from 2494 small, 1485 medium, and 396 large follicles were quantified by radioimmunoassay. Stage of estrous cycle was estimated by visual examination of the corpus luteum. Follicles in stage 1 of the estrous cycle (d 1 to 4) had the highest estradiol-17 beta concentration and the smallest mean follicular diameter. Location of follicles relative to the corpus luteum had no influence on estradiol-17 beta concentrations. As follicular size increased, concentration of estradiol-17 beta also increased. The presence of a single large follicle did not affect the concentration of estradiol-17 beta in medium or small follicles. In contrast, if multiple large follicles occurred in the same cow, concentrations of estradiol-17 beta were significantly lower in medium but not small follicles. 相似文献
923.
Alkali-metal carbonate salts meet the requirements for high-temperature solar central receiver systems, but because of their corrosiveness they present special problems in the design of storage tanks. In order to reduce corrosion and temperature sufficiently to retain strength in the storage containing wall, internal and thermal insulation is required. We present design options and operation criteria for sensible-heat, molten-salt storage with internal insulation. 相似文献
924.
V. G. Khoruzhaya K. E. Kornienko P. S. Martsenyuk T. Ya. Velikanova 《Powder Metallurgy and Metal Ceramics》2006,45(5-6):251-258
Methods of differential thermal analysis, x-ray diffraction, microstructural analysis and electron probe microanalysis are
used to study alloys of the Al-Rh system over the whole concentration range. It is established that the phase of equiatomic
composition AlRh melts congruently at 2060°C and it has an extended range of homogeneity (45.1–54.2 at.% Rh). The solubility
of aluminum in rhodium reaches 9 at.%, decreasing to 6 at.% at 850°C. Coordinates are determined for the eutectic point l
⇆ AlRh + 〈Rh〉 as 70 at.% Rh and 1715°C. The existence of intermediate phases, their crystal structure, and also the method
of forming phases in the field of composition rich in aluminum given in publications are confirmed.
__________
Translated from Poroshkovaya Metallurgiya, Nos. 5–6(449), pp. 48–56, May–June, 2006. 相似文献
925.
Rudolph M. Behtash R. Doerner R. Hirche K. Wurfl J. Heinrich W. Trankle G. 《Microwave Theory and Techniques》2007,55(1):37-43
This paper presents a detailed analysis of the stressing mechanisms for highly rugged low-noise GaN monolithic-microwave integrated-circuit amplifiers operated at extremely high input powers. As an example, a low-noise amplifier (LNA) operating in the 3-7-GHz frequency band is used. A noise figure (NF) below 2.3 dB is measured from 3.5 to 7 GHz with NF<1.8 dB between 5-7 GHz. This device survived 33 dBm of available RF input power for 16 h without any change in low-noise performance. The stress mechanisms at high input powers are identified by systematic measurements of an LNA and a single high electron-mobility transistor in the frequency and time domains. It is shown that the gate dc current, which occurs due to self-biasing, is the most critical factor regarding survivability. A series resistance in the gate dc feed can reduce this gate current by feedback, and may be used to improve LNA ruggedness 相似文献
926.
I. E. Gorbatkina L. D. Konoval'chikov B. K. Nefedov B. L. Khusid 《Chemistry and Technology of Fuels and Oils》1989,25(3):127-130
Translated from Khimiya i Tekhnoloyiya Topliv i Masel, No. 3, pp. 3–5, March, 1989. 相似文献
927.
Eight lactating Holstein dairy cows were fed corn silage-based diets with or without whole cottonseed at 18.5% of the dietary dry matter. At 42 days postpartum, a pulse injection of 100 mg glucose/kg body weight was given intravenously and plasma glucose concentration was monitored for 45 min. At 50 d postpartum, biopsies of adipose tissue and mammary tissue were taken and tissue slices were incubated in vitro with either uniform carbon-14 glucose or 1-carbon-14 palmitate. Basal concentration of plasma glucose was not affected by diet, although apparent distribution volume of glucose did seem to decrease due to feeding whole cottonseed. Feeding whole cottonseed decreased uptake of glucose and palmitate in both adipose tissue and mammary tissue and also decreased oxidation of glucose to carbon dioxide in both tissues. Palmitate oxidation was not affected by diet. Incorporation of carbon-14 from glucose into adipose tissue lipids was decreased in cows fed whole cottonseed. Results indicate that fat supplementation in the form of whole cottonseed may decrease palmitate incorporation and glucose utilization for glycerol and reducing equivalent synthesis in both adipose tissue and mammary tissue of lactating dairy cows. 相似文献
928.
Most of the UK nuclear power reactors are gas-cooled and graphite moderated. As well as acting as a moderator the graphite also acts as a structural component providing channels for the coolant gas and control rods. For this reason the structural integrity assessments of nuclear graphite components is an essential element of reactor design. In order to perform graphite component stress analysis, the definition of the constitutive equation relating stress and strain for irradiated graphite is required. Apart from the usual elastic and thermal strains, irradiated graphite components are subject to additional strains due to fast neutron irradiation and radiolytic oxidation. In this paper a material model for nuclear graphite is presented along with an example of a stress analysis of a nuclear graphite moderator brick subject to both fast neutron irradiation and radiolytic oxidation. 相似文献
929.
A. K. Komarov 《Optoelectronics, Instrumentation and Data Processing》2007,43(3):274-277
Passive mode-locking with equidistant ultrashort pulses in the laser cavity due to additional weak modulation of the losses
or the refractive index is analyzed. The velocity of the relative pulse motion and the time of establishing the harmonic passive
mode-locking mode are analytically estimated.
Original Russian Text ¢ A.K. Komarov, 2007, published in Avtometriya, 2007, Vol. 43, No. 3, pp. 100–104. 相似文献
930.
An expression is derived for the probability of error of an N th-order selection diversity system for the case where the receiver is forced to swell on one channel for several symbols before being allowed to make a decision regarding the best channel. It is found that the time-varying nature of a fading channel causes significant degradation of the probability of error when the dwell time becomes longer than about 10% of the inverse of the fading bandwidth of the channel. The onset of degradation is a function of the signal-to-noise ratio and of the order of diversity. Specific probabilities of error are calculated for differential phase-shift keyed modulation (DPSK). However, the calculations can be done for any other modulation technique 相似文献