The emission properties of poly(N-vinylcarbazole) (PVK), poly(N-ethyl-2-vinylcarbazole), and poly(N-ethyl-3-vinylcarbazole) have been investigated. Dilute fluid solutions all three vinylcarbazole polymers are observed to exhibit a structureless band at energies approximately 5400 cm−1 the red (0,0) normal molecular fluorescence isolated monomer compounds. On basis earlier work appropriate model compounds, this is assigned as that from an intrachain excimer state in which two interacting...

Abstract The phase transition in a copolymer of 55% vinylidene fluoride and 45% trifluoroethylene near 70°C has been investigated by measuring the temperature dependence fundamental properties. remanent polarization disappeared 70°C. dielectric relaxation strength showed peak indicating an anomaly time critical slowing down phenomenon. A change crystal lattice spacing associated with strain anomalous specific heat were observed. These results are consistent ferroelectric transition....

Abstract The present paper uses a social selection and adaptation framework to investigate whether problematic substance use normally precedes or follows homelessness. Clarifying temporal order is important for policy program design. information from large dataset (n=4,291) gathered at two services in Melbourne, supplemented by 65 indepth interviews. We found that 43% of the sample had abuse problems. Of these people, one-third problems before they became homeless two-thirds developed after...

This article uses information from a large administrative database ( N = 3941) to outline five ideal typical pathways into adult homelessness. The are called ‘housing crisis’, ‘family breakdown’, ‘substance abuse’, ‘mental health’ and ‘youth adult’. Then we explain why people on some remain homeless for longer than others. People housing crisis or family breakdown pathway do not form strong friendships in the subculture accept homelessness as way of life. Their is shorter. In contrast,...

The ferroelectric switching characteristics of polyvinylidene fluoride have been investigated by the time domain measurement electric displacement under a step-function field up to 200 MV/m at temperatures between −100 and 20 °C. Almost complete reversal polarization is found occur in fairly short if applied sufficiently high. 4 μsec °C increases significantly as either or temperature decreases. rate change greater than associated with single relaxation process. This an indication...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSpectroscopic study of carbazole by photoselectionG. E. JohnsonCite this: J. Phys. Chem. 1974, 78, 15, 1512–1521Publication Date (Print):July 1, 1974Publication History Published online1 May 2002Published inissue 1 July 1974https://pubs.acs.org/doi/10.1021/j100608a014https://doi.org/10.1021/j100608a014research-articleACS PublicationsRequest reuse permissionsArticle Views750Altmetric-Citations123LEARN ABOUT THESE METRICSArticle Views are the...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCompatibility in Blends of Poly(methyl methacrylate) and Poly(styrene-co-acrylonitrile). 1. Physical PropertiesK. Naito, G. E. Johnson, D. L. Allara, T. K. KweiCite this: Macromolecules 1978, 11, 6, 1260–1265Publication Date (Print):November 1, 1978Publication History Published online1 May 2002Published inissue 1 November 1978https://pubs.acs.org/doi/10.1021/ma60066a037https://doi.org/10.1021/ma60066a037research-articleACS PublicationsRequest reuse...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSolubility and diffusion of water in low-density polyethyleneD. W. McCall, Dean C. Douglass, L. Blyler Jr., G. E. Johnson, Lynn Jelinski, H. BairCite this: Macromolecules 1984, 17, 9, 1644–1649Publication Date (Print):September 1, 1984Publication History Published online1 May 2002Published inissue 1 September 1984https://pubs.acs.org/doi/10.1021/ma00139a001https://doi.org/10.1021/ma00139a001research-articleACS PublicationsRequest reuse...

To confirm and extend further our previous prediction of a Curie transition in PVF2, we examined copolymer it with tetrafluoroethylene (81 mol % VF2). The units serve to render this equivalent PVF2 slightly increased head-to-head content. Contrary other reports, have detected material using x-ray diffraction, dielectric, calorimetric techniques. ferroelectric-to-paraelectric transformation is barely perceptible because begins at ∼122 °C (which only below the main melting point) rapidly...

The emission properties of various carbazole ``double'' molecules in solution have been investigated. One compound particular, namely 1,3-bis(N-carbazolyl) propane, a useful model coumpound for poly(N-vinylcarbazole), has studied detail. Both steady state and transient measurements are utilized to determine rate thermodynamic parameters the formation intramolecular excimers. Results on other coumpounds which groups symmetrically or unsymmetrically attached 1,3 positions propane chain used...

In Australia, it is widely believed that most homeless people have mental health issues and illness a primary cause of homelessness. This paper uses information from study 4,291 in Melbourne to investigate these propositions. The research found 15 per cent the had prior becoming homeless. challenges community perception also 16 sample developed after Homelessness causes for some people, particularly anxiety depression. claim are mentally ill sends wrong message policy makers about services...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPhotoinduced Doping and Photolithography of Methyl-Substituted PolyanilineG. Venugopal, X. Quan, G. E. Johnson, F. M. Houlihan, Chin, O. NalamasuCite this: Chem. Mater. 1995, 7, 2, 271–276Publication Date (Print):February 1, 1995Publication History Published online1 May 2002Published inissue 1 February 1995https://pubs.acs.org/doi/10.1021/cm00050a007https://doi.org/10.1021/cm00050a007research-articleACS PublicationsRequest reuse permissionsArticle...

Abstract

Governments have shown an interest in early intervention strategies to reduce youth homelessness, but critics say that programs lack clear outcomes. This paper investigates what happens when are not place and young people progress adult homelessness. The assesses the ‘social adaptation’ hypothesis longer homeless more they adapt homelessness as a way of life. uses information on 1,677 individuals who first became were 18 or younger. Three‐quarters sample had progressed (defined 25 older)...

The time dependence of polarization reversal in β-phase polyvinylidene fluoride has been measured under a step-function field up to 200 MV/m below room temperature. Fairly fast switching found occur which might be accomplished by 180° rotation individual chains around their chain axes the crystalline lamellae. is strong as indicated very high activation 1–2 GV/m or large power law index 8.0–10.5. shape transient investigated phenomenologically and computer simulation on basis nucleation...

Dynamic dielectric measurements were carried out for a copolymer of vinylidene fluoride (55 mol %) and trifluoroethylene (45 over the frequency range 50 Hz–50 MHz at temperatures between −15 130 °C. Observed relaxations associated with crystalline phase transition 70 °C found to fit Cole-Cole arc distribution relaxation times. The equilibrium constant e(0) shows anomaly in that it rapidly increases just below then decreases. logarithm observed time t vs 1/T (K−1) shoulder near which is...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPhenomenological relationship between dielectric relaxation and thermodynamic recovery processes near the glass transitionS. Matsuoka, G. Williams, E. Johnson, W. Anderson, T. FurukawaCite this: Macromolecules 1985, 18, 12, 2652–2663Publication Date (Print):December 1, 1985Publication History Published online1 May 2002Published inissue 1 December 1985https://pubs.acs.org/doi/10.1021/ma00154a048https://doi.org/10.1021/ma00154a048research-articleACS...

Abstract This article explores narratives of homeownership by middle‐class Australians in the context an increasingly complex and volatile housing market. Our analysis focuses on people's perceptions feelings security anxiety at different stages their careers. We use concepts ontological risk society to frame analysis. The participants' were mainly positive, tune with a well established idea as fulfilment 'great Australian dream', view that influences status, identity sense belonging...

Abstract Elevated temperatures and high humidity decrease the molecular weight impact strength of polycarbonate. Hydrolysis injection molded polycarbonate (PC) bars stored in glass containers at 85°C 96% relative (RH) produced brown surface crystals within 30 days. Aging PC RH 70°C lower for longer periods time formed a liquid coating on PC. X‐ray, DSC, GPC measurements indicated that about 70 wt% were bisphenol A (BPA). The remaining portion hydrolysis products appeared to be higher...

A semi-empirical molecular orbital calculation, using the CNDO/S spectral parameterization of Del Bene and Jaffe, has been carried out for carbazole. The ground state occupied eigenvalues are used to provide an assignment photoelectron spectrum limited configuration interaction procedure, utilizing lowest 60 singly excited configurations, is subsequently determine energies singlet triplet states Agreement between theoretical calculations experimental results lower lying electronic...

Polycarbonate absorbs water in two stages: the initial period of absorption at an elevated temperature all was found unassociated state when cooled to room temperature; and, second stage, most additional absorbed by polymer identified a separate liquid phase (clustered water). From sorption studies on polycarbonate bars, we advance following model for formation clusters. After is saturated with and cooled, its solubility lowered condenses form microscopic water-filled cavities, providing...

Rate constants for intramolecular excimer formation and dissociation in 1,3-bis(N-carbozolyl)propane have been measured a number of different solvents using time resolved fluorescence decay techniques. It is found that within homologous series both rate decrease progressively with increasing viscosity obey relationship originating the concept free volume requirements conformational change. Among group chemically structurally are observed to vary randomly macroscopic solvent indicating other...

The apparent elimination half‐lifes were determined for 4 drugs that undergo hydroxylation in men. Glutethimide (500 mg), amobarbital sodium (130 antipyrine (1.0 gm), and sulfinpyrazone (400 mg) each taken orally by 10 healthy men at weekly intervals. When the these individuals compared, positive correlations found among 3 out of drugs: glutethimide‐amobarbital (r 0.69, p < 0.05), glutethimide‐sulfinpyrazone 0.64, amobarbital‐sulfinpyrazone 0.87, 0.01). If data are generally valid, it...