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121.
In the assessment of family cohesion and adaptability, researchers typically overlook the possibility that different components of the family may be more cohesive or adaptable than others. This potential problem is often compounded by monomethodism, reliance on a single source of information. Using a multitrait-mutimethod approach, we obtained three measures of cohesion and adaptability in three component dyads of relatively healthy families. Mothers, fathers, and college students reported about cohesion and adaptability in the mother–student, father–student, and mother–father relationships. Using confirmatory factor analysis, we found significant differences in the convergent validities of mothers', fathers', and students' reports. Furthermore, significant differences emerged among the correlations between mother–father, mother–student, and father–student cohesion (and adaptability), which suggests that noteworthy differences exist between family subsystems on these constructs. Implications for assessment strategies in marital and family counseling are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
122.
The IUPAC Thermodynamic Tables Project Centre in London has at its disposal considerable expertise on the production and utilization of high-accuracy equations of state which represent the thermodynamic properties of substances. For some years they have been content to propagate this information by the traditional method of book production, but the increasing use of the computer in industry for process design has shown that an additional method was needed. The setting up of the IUPAC Transport Properties Project Centre, also at Imperial College, whose products would also be in demand by industry, afforded the occasion for a new look at the problem. The solution has been to set up the Imperial College Thermophysical Properties Data Centre, which embraces the two IUPAC Project Centres, and for it to establish a link with the existing Physical Properties Data Service of the Institution of Chemical Engineers, thus providing for the dissemination of the available information without involving the Centres in problems such as those of marketing and advertising. This paper outlines the activities of the Centres and discusses the problems in bringing their products to the attention of industry in suitable form.Paper presented at the Ninth Symposium on Thermophysical Properties, June 24–27, 1985, Boulder, Colorado, U.S.A.  相似文献   
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A H Cole  I O Udekwe 《Die Nahrung》1989,33(8):703-708
100 apparently healthy female nursing students (aged 20-30 years) were studied. A 24 hours dietary recall was recorded. Additionally a questionnaire was elaborated to collect dietary parameters for 3 days. From the mean daily food intake the energy, protein and iron intake was calculated. A series of anthropometric measurements, i.e. body weight, body height and skinfold thickness (triceps, breast, scapula, abdomen) were used to determine total body fat, lean body mass, optimum weight, and relation weight. The mean total body fat of the 100 subjects was (21.3 +/- 5.1) % and (12.7 +/- 4.4) kg, respectively, the optimum weight (56.6 +/- 6.3) kg and the mean relative weight (101 +/- 12.4) %. 11% of the 100 subjects studied was underweight, 73% showed normal weight, 10% was overweight and 6% obese. All the age groups met their energy and protein requirements as well as the iron intake.  相似文献   
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We derive the shape of the interface between vapor and a physisorbed film on a substrate composed of two media. This represents a simple example of adsorption on a heterogeneous surface. The results are explained in terms of competition between the surface energy and potential energy due to the substrate. Applications to superfluid onset and third sound attenuation are considered.  相似文献   
128.
Cone calorimetry studies showed that various metal‐exchanged clays and zeolites containing only 3–4% of Cu(II), Cu(I), Zn(II), or Al(III) were effective smoke suppressants and fire retardants for plasticized poly(vinyl chloride). Copper(II)‐Zn(II) and Cu(II)‐Al(III) synergism for smoke and heat reduction was observed with binary blends of the clays, and the effectiveness of the additives was usually improved considerably by heating plasticizer‐additive mixtures under very high shear before combining them with the polymer. Possible mechanisms of action of the additives are described. J. VINYL ADDIT. TECHNOL., 2009. © 2009 Society of Plastics Engineers  相似文献   
129.
MEMS-tunable vertical-cavity SOAs   总被引:1,自引:0,他引:1  
We present the signal gain, wavelength tuning characteristics, saturation properties, and noise figure (NF) of MEMS-based widely tunable vertical-cavity semiconductor optical amplifiers (VCSOAs) for various optical cavity designs, and we compare the theoretical results to data generated from a number of experimental devices. Using general Fabry-Pe/spl acute/rot relationships, it is possible to model both the wavelength tuning characteristics and the peak signal gain of tunable vertical-cavity amplifiers, while a rate-equation analysis is used to describe the saturation output power and NF as a function of the VCSOA resonant wavelength. Additionally, the basic design principles for an integrated electrostatic actuator are outlined. It is found that MEMS-tunable VCSOAs follow many of the same design trends as fixed-wavelength devices. However, with tunable devices, the effects of varying mirror reflectance and varying single-pass gain associated with the MEMS-based tuning mechanism lead to changing amplifier properties over the wavelength span of the device.  相似文献   
130.
Direct measurements of total reaction cross sections (sigma R) have been performed in the energy range of 10-300 MeV/nucleon for heavy ion collisions. A decrease of sigma R with increasing energy was observed for a wide range of masses of the colliding systems. The data suggest that sigma R reaches a minimum located around 300 MeV/nucleon independently of the projectile target combination. A dependence of sigma R on mass asymmetry of the svstem is also demonstrated. Trends of sigma R in this energy range are well reproduced by the predictions of a simple microscopic model based on individual nucleon-nucleon collisions. Our data have been employed in this framework to derive a new semi-empirical parametrization of sigma R. Most of the experimental results in the intermediate and high energy range have been reproduced by this parametrization using a single energy-dependent parameter.  相似文献   
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