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排序方式: 共有153条查询结果,搜索用时 15 毫秒
1.
Presents results of 3 studies on the psychometric properties of the LP-ABC (M. Loranger and M. Pépin, 1993), a French-language instrument for assessing general functioning in adults with mental retardation. The studies involved a total of 299 male and female Canadian adults with mental retardation. Results confirm the internal consistency, construct validity, criterion validity, discriminant validity, interrater reliability, and test–retest reliability of the LP-ABC. (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
A new crystalline structure of poly 4-methylpentene-1 (P4MP1), modiification named modification V, is obtained from cyclopentane solutions and gels, for polymer volume fractions between 0.01 and 0.10. The effect of the thermal history imparted to the solution is analyzed. The relation between gelation, polymorphism and existence of helical conformations of P4MP1 in solution is discussed. Modification V is tentatively indexed on the basis of an hexagonal unit cell with dimensions a = 22.17 ± 0.14 Å and c = 6.69 ±0.02 Å. The crystal transforms into modification I at 130 ± 5°C, the heat of transition being + 15 ±2 J.g?1.  相似文献   
3.
This paper proposes a model of a three phase electrical inverter with a LC output filter in delta connection used in a renewable energy supply system. The concept of inverse bond graph via bicausality is used for the control law design. The control law robustness is tested by connecting passive and active (induction machine) loads.  相似文献   
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Four mesocosms were exposed to circumneutral and aluminum (Al)-rich wastewater during two successive summers (2000, 2001). The goals of the study were to measure the bioaccumulation of dissolved Al by the aquatic plants Typha latifolia, Lemna minor, Nuphar variegatum and Potamogeton epihydrus, and to evaluate their importance in the retention of Al by the mesocosms. In 2000, inlet concentrations of total monomeric Al were reduced by 56% and 29% at the Arvida and Laterrière mesocosms, respectively, whereas in 2001 inlet dissolved Al concentrations in the inlet decreased by 40% and 33%. L. minor had the highest Al uptake rate (0.8--17 mg Al g(-1)d(-1)). However, because T. latifolia (cattails) yielded the highest biomass, it was responsible for 99% of the Al uptake, largely in its root tissue. In 2001, Al uptake by macrophytes accounted for 2--4% and 15--54% of the total Al retained by the Laterrière and Arvida mesocosms, respectively. In the Laterrière mesocosms, Al uptake by cattails could account for 12% and 18% of the dissolved Al retained by both mesocosms. In contrast, dissolved Al was not significantly reduced in the Arvida enclosures, yet cattails did accumulate Al in their roots. Further research is needed to identify the species community composition that would optimize dissolved Al retention.  相似文献   
6.
This longitudinal study investigated the presence of a moderating effect of pregnancy planning on the relationship between marital status and parenting satisfaction of couples experiencing the transition to parenthood and verified whether this moderating effect is mediated by role overload. Data were collected from 150 Canadian couples during the 3rd trimester of pregnancy and at 9 months postpartum. Findings reveal that when the pregnancy is planned, the poorer parenting satisfaction reported by cohabiting fathers in comparison with their married counterparts can be explained by cohabiting men’s higher levels of role overload. Women’s levels of parenting satisfaction are also influenced by their own and their partner’s experiences of role overload. Results are discussed in terms of the respective values and lifestyles of cohabiting and married couples and specifically in terms of their different attitudes toward egalitarianism. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
Hadjur C  Daty G  Madry G  Corcuff P 《Scanning》2002,24(2):59-64
The optical sectioning property of the confocal microscope offers a breakthrough from the classic observation of the hair in a scanning electron microscope (SEM). Confocal microscopy requires minimal sampling preparation, and the hair can be observed in its natural environment with less damage than by other microscopic methods such as SEM. While used in the reflection mode, the true morphology of the cuticle and the various exogenous deposits at the surface can be identified and quantified. This relatively noninvasive, nondestructive technique is routinely used by us to monitor the efficiency of cleansing shampoos, to assess the homogeneity of layering polymers, and to evaluate the changes they induce in the optical properties of the hair surface in terms of opacity, transparency, and brilliancy. A second important field of investigation uses the fluorescence channel which reveals the internal structure of the hair. Fluorescent probes (rhodamine and its derivatives) demonstrate the routes of penetration and outline the geometry of cortical cells and of the medulla according to their lipophilic or hydrophilic properties. A volume rendering of a hair cylinder provides a better understanding of the interrelationships between cuticle cells, cortical cells, and the medullar channel. This recent technology is becoming an invaluable tool for the cosmetic assessment of the hair.  相似文献   
8.
We report on systematic low-field NMR measurements on room temperature 3 He gas imbibed into a 98% porous silica aerogel. Laser polarised helium is used to obtain large NMR signals at 0.1 T even for small amounts of gas. We use a multi-echo technique in a controlled magnetic field gradient to characterize spin diffusion. Measurements are carried out for pressures P ranging from 10 mbar to 1 bar (mean free path of free 3 He ranging from 19 to 0.19 m respectively). In a free gas, the damping rate 1/T 2 of the amplitude of the echoes is checked to be proportional to the known diffusion coefficient (T 2 P). Damping rates 2–5 times smaller than those in a free gas are measured within the aerogel. This reduction is quite significant at 1 bar, suggesting that 3 He- 3 He and 3 He-silica collisions occur with comparable frequencies at this density. However, a stong dependence of T 2 on P is still observed at low pressure, revealing a significant reduction of diffusion due to binary atomic collisions even for the lowest gas density. Measurements over such a large range of gas densities indirectely probe collisional effects over a wide range of sizes up to tens of m. In our sample, results are not consistent with a single geometrical mean free path for 3 He-silica collisions.  相似文献   
9.
Studied the psychometric properties and the theoretical validity of the French translation of the Inventory of Personality Organization (IPO; O. F. Kernberg and J. F. Clarkin, 1995). The IPO was administered to 845 males and females from a Quebec university and from the general Quebec population. Separate exploratory and 1st-level confirmatory factor analyses were performed. The results indicate a good level of conformity between IPO items and the tridimensional primary constructs of O. F. Kernberg's theoretical model of personality organization. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
Examined the relationships between adolescents' attachment, cognitive organization, and their perceptions of control and support in an academic mentoring relationship. 98 students involved in a volunteer mentoring program were interviewed using the Adult Attachment Interview (AAI). Perceptions of security and control in the mentor-student relationship and perceptions of the program effectiveness were also assessed at the end of the program and 4 mo later. Results show that both adolescents' dismissing and preoccupied strategies in the AAI were negatively associated with their interpersonal perceptions of the mentoring experience. Some of these relationships were moderated by the sex of the dyad (same-sex vs opposite-sex). These findings are discussed in light of theoretical postulates of attachment theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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