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51.
Isabel Vega Emiliano Fernández Carmen Mijangos Norma D'Accorso Daniel López 《应用聚合物科学杂志》2008,110(2):695-700
The authors report on the viscoelastic characterization of guar hydrogels obtained through complexation reactions with borax ions. These gels are compared with hydrogels obtained from poly(vinyl alcohol) of different degree of hydrolysis through complexation reactions with congo red. The effect of the degree of hydrolysis and both, the concentration of PVA and the concentration of congo red, on the viscoelastic properties of the hydrogels is analyzed. The potential use of the PVA‐based hydrogels as hydraulic fracturing liquids is discussed in relation to the commonly used fracturing liquid based on the guar–borax system. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
52.
It's no longer just black hats or white hats in computer security. The more someone has to lose, the less likely they should be to trust the computer. It means that all people, all programs, all transactions are shades of grey. Black and white are just a memory. 相似文献
53.
OBJECTIVE: The objective of this review was to evaluate the clinical and research literature on professionally-led support groups for cancer patients and to propose an approach that would address patients' needs from diagnosis through survivorship. METHOD: Computerized and manual searches, including Medline and Psychlit searches, were completed for reviews of the literature. Twelve research studies were identified that met our criteria for in-depth review. A clinical model emerged from discussions of an oncology study group based on theoretical formulations and clinical experience with oncology patients. RESULTS: We found that recent research suggests that professionally-led support groups are increasing in number and that participation in such groups seems to enhance patients' quality, and possibly even quantity, of survival. Despite this, little effort has been made to determine what type of group may be appropriate for which patients and when in their course of care. CONCLUSIONS: If psychosocial intervention, in the form of professionally-led support groups for cancer patients, is to be more effective, it should be guided by a model which takes into consideration the changing needs and concerns of patients over the course of illness and, in many cases, recovery. The authors present an outline delineating what such a model might entail. 相似文献
54.
McIntosh Daniel N.; Silver Roxane Cohen; Wortman Camille B. 《Canadian Metallurgical Quarterly》1993,65(4):812
Parents (N?=?124) who had lost an infant to sudden infant death syndrome were interviewed 3 wks and 18 mo postloss. Two components of religion (religious participation and religious importance) were assessed, and their relations with 3 coping-process variables (perceived social support, cognitive processing of the loss, and finding meaning in the death) were examined. Greater religious participation was related to increased perception of social support and greater meaning found in the loss. Importance of religion was positively related to cognitive processing and finding meaning in the death. Furthermore, through these coping-process variables, religious participation and importance were indirectly related to greater well-being and less distress among parents 18 mo after their infants' deaths. Results suggest that further study of the social and cognitive aspects of religion would be profitable. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
Daniel Bethge 《真空研究与实践》1996,8(2):84-87
The distillation in the fine and high vacuum range requires not only appropriate vacuum pumps but also special apparatus and machines. The principle and the design of laboratory and industrial plants are explained. New mathematical methods are supporting laboratory and pilot testing required for process development and plant layout. An example was chosen for demonstration purposes. 相似文献
56.
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58.
Prem Kalra Angelo Mangili Nadia Magnenat Thalmann Daniel Thalmann 《Computer Graphics Forum》1992,11(3):59-69
This paper describes interactive facilities for simulating abstract muscle actions using Rational Free Form Deformations (RFFD). The particular muscle action is simulated as the displacement of the control points of the control-unit for an RFFD defined on a region of interest. One or several simulated muscle actions constitute a Minimum Perceptible Action (MPA), which is defined as the atomic action unit, similar to Action Unit (AU) of the Facial Action Coding System (FACS), to build an expression. 相似文献
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60.
Given integers m and n, we study the probability that structures of size n have all components of size at most m. The results
are given in term of a generalized Dickman function of n/m. 相似文献