Search results for "Solid"
showing 10 items of 3575 documents
Ordering the amorphous – Structures in PBD LED materials
2012
Abstract The class of 2,5 disubstituted-1,3,4-oxadiazoles containing a biphenyl unit on one side is intensively used as electron transport materials to enhance the performance of organic light emitting diodes (OLEDs). In contrast to the ongoing research on these materials insights in their structure-property relationships are still incomplete. To overcome the structural tentativeness and ambiguities the crystal structures of 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole, that of the related compound 2-(4-biphenylyl)-5-phenyl-1,3,4-oxadiazole and of 2-(4-biphenylyl)-5-(2,6-dimethylphenyl)-1,3,4-oxadiazole are determined. A comparison with the results of GAUSSIAN03 calculations and…
EFFECT OF DRAWING ON THE STRUCTURE AND THE DYNAMIC-MECHANICAL BEHAVIOR OF SALTED POLYCAPROAMIDE.
1982
Abstract Structural determinations, obtained through density, birefringence, and WAXS measurements, are reported for nylon 6/inorganic salt fiber samples as a function of draw ratio. They confirm the possibility of achieving very high amorphous orientation in these systems. Dynamic-mechanical data have also been collected which allow determination of glass transition temperatures. These are also discussed in terms of structural parameters.
Study of the Curing Process of DGEBA Epoxy Resin Through Structural Investigation
2015
In this work, a multi-scale approach with different analytical methods is applied to study the curing process and the structural properties of a diglycidyl ether of bisphenol A (DGEBA) epoxy resin. This monomer, thermally cured using 4,4′-diaminodiphenilsulfone (DDS) as hardener, is analyzed after 10, 45, 90, and 120 min of reaction time at 180 °C to obtain information on samples with different cross-linking densities. Samples are also characterized after extraction in acetone in order to obtain structural information on the insoluble parts. For this purpose, differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), solid-state nuclear magnetic resonance (ss-NMR),…
An automatic flow-through system for exploration of the human bioaccessibility of endocrine disrupting compounds from microplastics
2021
This article reports on the first attempt towards investigating the leaching rates in the human gastrointestinal (GI) tract of plastic-borne contaminants that can be ingested accidentally using physiologically relevant body fluids. Oral bioaccessibility under fasted and fed states was determined in dynamic mode exploiting an automatic flow setup. The flow system is able to mimic the fast uptake of the released species from the polymeric matrix by absorption in the human digestive system by the in-line removal of the leached species. Complex GI extractants based on the Unified Bioaccessibility Method (UBM, fasted state) and Versantvoort test (fed-state) were brought through a microplastic-lo…
Konsolidācija Aktīvu pārvaldīšanas nozarē un ietekme uz darbības procesiem
2018
Finanšu pakalpojumu vide neapšaubāmi ir ļoti mainīga un tuvākajos gados Aktīvu Pārvaldes nozarē būs nopietnas radikālās izmaiņas. Regulatori un tehnoloģijas attīstība veicina finansiālu sistēmu uz lielajām pārmaiņām. Pēdējos gados palielinājās ieguldījumu plūsma kompānijām, kas izmanto vienīgu apstrādes programmu, ar apkopoto datu analīzi. Tajā mākslīgais intelekts palīdz interpretēt finansiālo informāciju. Ar minētajām izmaiņām aktīvu pārvaldes dalībniekiem būs jāveido virkne jaunu analītisko rīku, jo cilvēki nebūs spējīgi apstrādāt visus datus patstāvīgi. Esošais cilvēka un mašīnas līdzsvars, turpinās noliekties vairāk un vairāk uz mašīnas pusēs, kamēr cilvēks gandrīz pilnīgi būs aizvieto…
Manger (et boire) dans les usines occupées du printemps 1936
2016
International audience; Avec celles de 1968, les grèves du Front populaire constituent l’un des épisodes les plus marquants et les plus étudiés de l’histoire du mouvement ouvrier français, élevé au rang de « mythes sociaux » . Si la chronologie des évènements est aujourd’hui bien connue, nos connaissances sur l’organisation pratique et technique de ces grèves demeurent néanmoins limitées. Et quand il s’agit d’aborder la question du ravitaillement, nous entrons cette fois dans une sorte de « no man’s land » de la recherche. Aussi s’intéresser à la nourriture dans les usines occupées de 1936 présente un double intérêt, scientifique d’abord au vu de l’état de l’art, et historique ensuite quand…
La Constitución y Porto-Davos
2005
One changing and challenging scenario: the treatment of cancer patients with bone metastases by bisphosphonates and denosumab, the cost-benefit evalu…
2022
Antiresorptive drugs (bisphosphonates and denosumab) have become the cornerstone of medical supportive treatment of bone metastases in solid cancer patients. In the beginning, the choice of available antiresorptive agents was limited to bisphosphonates and the treatment options restricted principally to monthly pamidronate and monthly zoledronic acid. Introduction of new antiresorptive therapies (monthly denosumab) and schedules (zoledronic acid every 3 months, upfront or after initial period of monthly infusion) in the last decade increased the range of available options, thus challenging treatment decision making. Direct and indirect costs of very different treatment options are difficult…
Improvement of solid state Er:YAG pulse laser performance for use in medicine
1999
The large quadratic electro-optic effect of PLZT ceramics allows to design small size modulators for the solid state infrared Er:YAG laser (lasing at (lambda) equals 2.94 micrometers - the most pronounced absorption band of water), which has found application in medicine for efficient ablation of hard and soft tissues. In the free-running mode, the Er:YAG laser emits spikes that form the pulse envelope with duration of 150 - 800 microsecond(s) . An extracavity PLZT 8.5/65/35 ceramics modulator (aperture of 4 X 6 mm2 and length of 18 mm) was used to obtain (Pi) -shaped segments with the rise and decay times less than 5 microsecond(s) . That allows to reduce considerably the fraction of the p…
Uses of weeds as an economical alternative to processed wood biomass and fossil fuels
2016
Abstract The use of fossil fuels as a main source of energy is directly linked to global climate change (due to CO2 emission), so there is a necessity to find new, cheap and easily available energy sources for the earth’s inhabitants. Nowadays renewable energy sources are forced also for the mitigation of the effects of climate change as a result of greenhouse gases emission control. Decentralized sources of low-cost renewable fuels that may be used, in particular, in those households where there is no possibility of using gas or heat delivered from other sources should be of special interest. This paper describes the possibility of using untreated plants such as Canadian goldenrod (Solidag…