Stability and stabilization of polyacetylene,polyphenylacetylene, and acetylene/phenylacetylene copolymers

Polyacetylene, polyphenylacetylene, and acetylene/phenylacetylene copolymers were prepared. Both the physical and electrical properties of the copolymers were shown to vary with copolymer content. The conductivities of the iodine doped materials were measured as a function of time exposed to dynamic vacuum, constant current, and the atmosphere. Polyacetylene was found to be the most stable of the materials examined with the conductivity decreasing at a steady rate of approximately one order of magnitude per 1060 h in air. Polyphenylacetylene, on the other hand, decreased in conductivity much more rapidly with a catastrophic decrease after less than 250 h. Acetylene/phenylacetylene copolymers were found to exhibit intermediate behavior. Encapsulation by materials such as glass, silicone rubber, polyethylene, and epoxy resin was found to significantly reduce the rate at which iodine doped polyacetylene decreased in conductivity; however, with the exception of the glass encapsulants, the effect was temporary with the rate of decrease returning to its initial value within 200 h. The degradation process itself was found to be a two-stage phenomenon involving a preliminary loss of iodine followed by an oxidation of the polyene backbone.     

Tritium-Labeled Compounds V. Radioassay of Both Carbon–14 and Tritium in Films,With a Proportional Counter

A convenient procedure is described for the radioassay of both carbon-14 and tritium in water-soluble, nonvolatile compounds by means of a windowless, gas-flow, proportional counter. The materials are counted in uniform films of sodium O-(carboxymethyl) cellulose that are “infinitely thick” to the radiation of tritium but not to the radiation of carbon-14. Films of uniform thickness are obtained by new techniques which are described in detail.If only carbon-14 is present, its absolute activity can be calculated conveniently by means of an empirically established curve for the counting-efficiency. If both carbon-14 and tritium are present, the films are counted in the proportional counter and are then recounted in the presence of a screen that stops all radiation from tritium but only a portion of that from carbon-14. From a film with a thickness of 0.8 mg/cm², approximately 43 percent of the radiation of carbon-14 is counted. Of this emerging radiation, approximately 50 percent passes through a screen of ¼-mil double-aluminized “Mylar.” By use of suitable calibration curves for counting-efficiency, carbon-14 and tritium in the same sample can be calculated from the counts with, and without, the screen.Satisfactory analyses can be made with samples containing less than 0.001 microcurie of carbon-14 and 0.005 microcurie of tritium. The method is suitable for the radioassay of a wide variety of labeled materials.     

Relative effects of various word synthesis strategies on the phonics achievement of learning disabled youngsters.

Over a 2-day period, 105 children (84–216 mo old, WISC scores 67–231) were given lessons that provided direct instruction on a medial vowel sound, practice on monosyllabic words containing the sound, and specific transfer training on nonsense syllables. Word attack strategy was varied for the 5 treatment groups. Practice consisted of synthesis using initial bigrams and final consonants (co-g), initial consonants and final bigrams (c-og), a combination of initial and final bigram training, or letter-by-letter analysis and synthesis (c-o-g). The initial bigram strategy yielded significantly better performance on transfer words. This finding challenges popular approaches that emphasize rhyming patterns or letter-by-letter decoding. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Physical,chemical, and electrical properties of various preparations of polyacetylene

Polyacetylene samples were prepared using a number of different synthetic procedures. The products obtained differed in morphology, in microstructure and in cis/trans isomer content. Although all of the polymer samples could be doped with large amounts of iodine, their room temperature d.c. conductivities upon doping, varied widely. The conductivities were found to be most closely related to crystallinity; the highest conductivity was associated with the most crystalline materials. Conversely, low levels of conductivity coincided with the appearance of a broad peak in the x-ray diffraction pattern (2θ=16°) which has been attributed to the presence of amorphous regions.     

Ethanol preloads increase ethanol preference under concurrent random-ratio schedules in social drinkers.

Ethanol (ETOH) preference was measured following ETOH preload doses in normal social drinkers. 11 Ss participated in a 5-session, double-blind choice study. In Session 1, Ss sampled an ETOH beverage (0.8 g/kg). In Sessions 2–5, they consumed a preload beverage containing placebo or ETOH (0.25 or 0.5 g/kg). One hour later, they responded on 2 concurrent random-ratio (RR) schedules. One schedule was associated with ETOH as the reinforcer and the other with money. When the probability of earning money was low, Ss responded more on the ETOH schedule following both ETOH preloads compared with placebo. Consistent with the increased responding for ETOH, Ss reported increased desire for ETOH. These data demonstrate a priming effect of ETOH preloads in normal social drinkers. They also illustrate the use of concurrent RR schedules to quantify ETOH preference. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Orientation variance discrimination in amblyopia

Our previous results showed that while amblyopes can efficiently integrate visual signals, they are poor at segregating signals in noise. This could be either because integration detectors have broader bandwidths or because of a selective extrastriate segregation anomaly. One consequence of the former would be poorer variance discrimination. Using a two-alternative forced-choice paradigm, observers were asked to judge the orientational variance for arrays of 16 Gabors. All observers, be they normal or amblyopic, could perform the task similarly, although at high spatial frequencies, amblyopic eyes needed slightly more incremental variance than the normal eyes. We conclude that normals and amblyopes integrate signals in a similar way.     

Fostering active network management through SMEs’ practises

Managing the electricity network through ‘smart grid’ systems is a key strategy to address challenges of energy security, low carbon transitions and the replacement of ageing infrastructure networks in the UK. Small and medium enterprises (SMEs) have a significant role in shaping patterns of energy consumption. Understanding how their activities interrelate with changes in electricity systems is critical for active network management. A significant challenge for the transformation of electricity systems involves comprehending the complexity that stems from the variety of commercial activities and diversity of social and organizational practises among SMEs that interact with material infrastructures. We engage with SMEs to consider how smart grid interventions ‘fit’ into everyday operational activities. Drawing on analysis of empirical data on electricity use, smart metre data, surveys, interviews and ‘energy tours’ with SMEs to understand lighting, space heating and cooling, refrigeration and IT use, this paper argues for experimenting with the use of practise theory as a framework for bringing together technical and social aspects of energy use in SMEs. This approach reveals that material circumstances and temporal factors shape current energy demand among SMEs, with ‘connectedness’ an emergent factor.     

Charles R. (Bob) Schuster (1930–2011).

Charles R. (Bob) Schuster, an internationally recognized researcher on the psychopharmacology of drugs of abuse, passed away on February 21, 2011. Bob Schuster was a pioneer in the scientific study of addiction and one of the founders of a specialized research field called behavioral pharmacology. Bob mentored many young scientists, including 15 doctoral students, 9 postdoctoral fellows, and many visiting scientists from around the world, as well as junior faculty members at the academic institutions where he had faculty appointments. Bob was active in numerous professional organizations and was the recipient of many national and international awards. Personally, Bob Schuster touched the lives of a great many people: his students, colleagues, extended family, and many friends. Bob is survived by his wife and colleague Chris-Ellyn Johanson; four children, Lyzbett, Rebecca, Robert, and Alyson; and seven grandchildren. He is also survived by his sister Bette Quemore. He was a man of many talents, a loving husband and father, and a great friend. (PsycINFO Database Record (c) 2011 APA, all rights reserved)