ANALYSIS OF NONISOTHERMAL EXTRUDATE SWELL

Nonisothermal extrudate swell through capillary and annular dies was studied numerically using a control volume finite difference method. In order to examine the effect of the relevant dimensionless parameters on the swelling behavior of the extrudate, Newtonian liquids having a temperature dependent viscosity have been chosen and computations have been performed for various process conditions. Four dimensionless groups, i.e., the Peclet number (Pe), the Brinkman number (Br), the Biot number (Bi), and an exponential parameter β expressing the temperature dependence of viscosity, were examined respectively, and the sensitivity of each group on the swelling ratio was determined. The parameter β was found to be the most sensitive factor.     

Iron oxide colloids and their heterogenization by silica sol–gel entrapment: Catalytic and magnetic properties

Fe₃O₄ colloids modified by the chiral ligand cinchonidine were prepared with the goal of obtaining a magnetic and catalytic nano-material and were subsequently embedded in silica to form a heterogeneous catalyst. The systems were characterized by TEM and XRD measurements, while the Mössbauer technique was applied for measuring the magnetic properties of the Fe₃O₄ colloids. The hyperfine magnetic field distribution was consistent with one type of Fe oxide, namely, the magnetite (Fe₃O₄). These colloids, both as ‘quasi-homogenous catalysts’ (or soluble heterogeneous catalysts) and embedded in silica (heterogeneous catalysts) were employed in the selective hydrogenolysis of complex bicyclo[2.2.2]oct-7-enes (bicyclo[2.2.2]oct-2-enes when unsubstituted).     

Through Air Drying

Process of through-air-drying is becoming increasingly popular in the manufacture of textiles, non-wovens, tissue, and towel. Very high drying rates, enhanced product properties, i.e., softness, bulk, absorbency, unique 3D structure are the driving forces behind its increasing popularity. In this article, experimental results on convective heat and mass transfer and fluid flow characteristics of tissue and towel products using commercially realistic structures are presented. Comparison with literature data using wet pressed, dried, rewetted sheets indicate significant differences in drying and permeability characteristics confirming that the internal structure of the material does indeed play a significant role in through-air-drying and should be taken into account in modeling, optimization, and control of commercial systems.     

Freud, religion, and the presence of projective identification.

This article contends that Freud's discourses on religion--particularly toward the end of his life--have the earmarks of projective identification. Evidence for projective identification is gleaned from these works and from Freud's letters to friends and colleagues. The author argues that the sources of Freud's projective identification lay in 2 distinct childhood traumas: the relative absence of emotional consolation from his mother and the failure of his father to protect him. Old age and approaching death threatened to evoke feelings of helplessness and anxiety, which Freud handled, in part, by attacking the foundations of religious experience. This enabled Freud to acknowledge disappointment and hostility toward religious believers, while disclaiming the loss of and need for emotional consolation and protection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Using self-assembly for the fabrication of nano-scale electronic and photonic devices

Challenges facing the scaling of microelectronics to sub-50 nm dimensions and the demanding material and structural requirements of integrated photonic and microelectromechanical systems suggest that alternative fabrication technologies are needed to produce nano-scale devices. Inspired by complex, functional, self-assembled structures and systems found in Nature we suggest that self-assembly can be employed as an effective tool for nanofabrication. We define a self-assembling system as one in which the elements of the system interact in pre-defined ways to spontaneously generate a higher order structure. Self-assembly is a parallel fabrication process that, at the molecular level, can generate three-dimensional structures with sub-nanometer precision. Guiding the process of self-assembly by external forces and geometrical constraints can reconfigure a system dynamically on demand. We survey some of the recent applications of self-assembly for nanofabrication of electronic and photonic devices. Five self-assembling systems are discussed: 1) self-assembled molecular monolayers; 2) self-assembly in supramolecular chemistry; 3) self-assembly of nanocrystals and nanowires; 4) self-assembly of phase-separated block copolymers; 5) colloidal self-assembly. These techniques can generate features ranging in size from a few angstroms to a few microns. We conclude with a discussion of the limitations and challenges facing self-assembly and some potential directions along which the development of self-assembly as a nanofabrication technology may proceed.     

Allocentric-heading recall and its relation to self-reported sense-of-direction.

A sense of direction (SOD) computes the body's facing direction relative to a reference frame grounded in the environment. The authors report on three experiments in which they used a heading-recall task to tap the functioning of a SOD system and then correlated task performance with self-reported SOD as a convergent test of the task's construct validity. On each heading-recall trial, the participant judged the photographer's allocentric heading when photographing a pictured outdoor scene. Participants were tested over the full range of SOD ratings in Experiment 1, and in Experiments 2 and 3 heading-recall at the SOD extremes was tested. In all experiments, there was wide variability in heading-recall accuracy that covaried with self-rated SOD. Parametric manipulation of various task parameters revealed some likely functional properties of the SOD system. The results support the psychological reality of a SOD system and further indicate that there are large individual differences in the efficacy with which the system functions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Computation of estimates in segmented regression and a liquidity effect model

Weighted least squares (WLS) estimation in segmented regression with multiple change points is considered. A computationally efficient algorithm for calculating the WLS estimate of a single change point is derived. Then, iterative methods of approximating the global solution of the multiple change-point problem based on estimating change points one-at-a-time are discussed. It is shown that these results can also be applied to a liquidity effect model in finance with multiple change points. The liquidity effect model we consider is a generalization of one proposed by Çetin et al. [2006. Pricing options in an extended Black Scholes economy with illiquidity: theory and empirical evidence. Rev. Financial Stud. 19, 493-529], allowing that the magnitude of liquidity effect depends on the size of a trade. Two data sets are used to illustrate these methods.     

Task control and cognitive abilities of self and spouse in collaboration in middle-aged and older couples.

[Correction Notice: An erratum for this article was reported in Vol 22(4) of Psychology and Aging (see record 2007-18670-006). Due to an editing mistake, the order of authorship was incorrect. The correct order is as follows: Berg, Smith, Ko, Beveridge, Story, Henry, Florsheim, Pearce, Uchino, Skinner, & Glazer.] Collaborative problem solving may be used by older couples to optimize cognitive functioning, with some suggestion that older couples exhibit greater collaborative expertise. The study explored age differences in 2 aspects of collaborative expertise: spouses' knowledge of their own and their spouse's cognitive abilities and the ability to fit task control to these cognitive abilities. The participants were 300 middle-aged and older couples who completed a hypothetical errand task. The interactions were coded for control asserted by husbands and wives. Fluid intelligence was assessed, and spouses rated their own and their spouse's cognitive abilities. The results revealed no age differences in couple expertise, either in the ability to predict their own and their spouse's cognitive abilities or in the ability to fit task control to abilities. However, gender differences were found. Women fit task control to their own and their spouse's cognitive abilities; men only fit task control to their spouse's cognitive abilities. For women only, the fit between control and abilities was associated with better performance. The results indicate no age differences in couple expertise but point to gender as a factor in optimal collaboration. (PsycINFO Database Record (c) 2010 APA, all rights reserved)