Mutual effect of plasma oxygen and oxidative degradation of a polyethylene film

ABSTRACTIn this paper we report a method for tuning the extent of hole injection into the active light emitting tris- (8-hydroxyquinoline) aluminum (Alq3) layer in organic light emitting diodes (OLEDs). This is made possible by modifying the indium tin oxide (ITO) anode with an oxidized transport layer (OTL) comprising a hole transporting polycarbonate of N,N'-bis(3-hydroxymethyl)-N,N'-bis(phenyl) benzidine and diethylene glycol (PC-TPB-DEG) doped with varying concentrations of antimonium hexafluoride salt of N,N,N',N'-tetra-p-tolyl-4,4'-biphenyldiamine (TMTPD+ SbF6-). The conductivity of the OTL can be changed over three orders of magnitude depending on salt loading. The analysis of hole and electron current variations in these devices indicates that optimizing the conductivity of the OTL enables the modulation of hole injection into the Alq3 layer. The bipolar charge transport properties for OLEDs in which the interfacial carrier injection barriers have been minimized, are governed by the conductivities of the respective layers and in this case it is shown that the variable conductivity of the OTL does allow for better control of the same. Accordingly, varying the concentration of holes in the device indicates that beyond an optimum concentration of holes, further hole injection results in the formation of light quenching cationic species and the initiation of oxidative degradation processes in the Alq3 layer, thus accelerating the intrinsic degradation of these devices. The variable conductivity of the OTL can hence be used to minimize the occurrence of these processes.

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Simple Modification Measurement of Photodegradability of Polymers by using Photo-induced Chemiluminescence Technique

Scientific Research Journal ◽

10.24191/srj.v10i2.5414 ◽

2013 ◽

Vol 10 (2) ◽

pp. 51

Author(s):

Siti Farhana Zakaria ◽

Keith R Millington

Keyword(s):

Free Radicals ◽

Organic Materials ◽

Oxidative Degradation ◽

Working Life ◽

Bimolecular Reaction ◽

Synthetic Polymers ◽

Accelerated Weathering ◽

Simple Modification ◽

Uv Absorbers ◽

Irradiation Period

Polymers and organic materials that are exposed to sunlight undergo photooxidation, which leads to deterioration of their physical properties. To allow adequate performance under outdoor conditions, synthetic polymers require additives such as antioxidants and UV absorbers. A major problem with optimising polymer formulations to maximise their working life span is that accelerated weathering tests are empirical. The conditions differ significantly from real weathering situations, and samples require lengthy irradiation period. Degradation may not be apparent in the early stages of exposure, although this is when products such as hydroperoxides are formed which later cause acceleration of oxidation. A simple way of quantifying the number of free radicals presents in organic materials following exposure to light or heat is by measuring chemiluminescence (CL) emission. Most polymers emit CL when they undergo oxidative degradation, and it originates from the bimolecular reaction of macroperoxy radicals which creates an excited carbonyl.

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Effect of planting date and density on calendula and peppermint herbs

JOURNAL OF ADVANCES IN AGRICULTURE ◽

10.24297/jaa.v1i1.4241 ◽

2014 ◽

Vol 1 (1) ◽

pp. 25-29

Author(s):

Rahim Mohammadian ◽

Behnam Tahmasebpour ◽

Peyvand Samimifar

Keyword(s):

Mutual Effect ◽

Dry Weight ◽

Planting Date ◽

Mass Reduction ◽

Flower Number ◽

Planting Dates ◽

Randomized Design ◽

Significant Difference ◽

Completely Randomized Design ◽

Total Maximum

A factorial experiment was conducted with a completely randomized design to evaluate the effects of planting date and density on calendula herbs and peppermint. It had 3 replicates and was done in Khosroshahr research farm, Tabriz in 2006. Under studied factors were: 3 planting dates (10 May, 25 May and 10 June) in 4 densities (25, 35, 45, 55) of the plant in square meters. The results of variance a nalysis showed that there was 1% probability significant difference between the effects of planting date and bush density on the leave number, bush height and the bush dry weight. But the mutual effect of the plant date in mentioned traits density was insignificant. Regarding the traits mean comparison, the total maximum dry weight was about the 55 bush density in mm. Also, the bush high density in mm causes the bush growth and its mass reduction. When there is the density grain, the flower number will increase due to bush grain in surface unit. Overall, we can conclude that 10 June planting and 45 bush density in mm is the most suitable items and results in favored production with high essence for these crops.

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KINETICS CONSIDERATIONS CONCERNING THE OXIDATIVE DEGRADATION BY PHOTO-FENTON PROCESS OF SOME ANTIBIOTICS

Environmental Engineering and Management Journal ◽

10.30638/eemj.2010.001 ◽

2010 ◽

Vol 9 (1) ◽

pp. 1-5 ◽

Cited By ~ 1

Author(s):

Ion Untea ◽

Cristina Orbeci ◽

Madelene Dancila ◽

Daniela Simina Stefan

Keyword(s):

Oxidative Degradation ◽

Fenton Process

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A NEW PHOTO-FENTON PROCEDURE APPLIED IN OXIDATIVE DEGRADATION OF ORGANIC COMPOUNDS FROM WASTEWATER

Environmental Engineering and Management Journal ◽

10.30638/eemj.2012.019 ◽

2012 ◽

Vol 11 (1) ◽

pp. 141-146

Author(s):

Ion Untea ◽

Cristina Orbeci ◽

Rodica Stanescu ◽

Adina Elena Segneanu ◽

Mihaela Emanuela Craciun

Keyword(s):

Organic Compounds ◽

Oxidative Degradation

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DYNAMIC AND THERMAL INTERFERENCE EFFECTS ON TWO NEIGHBOURING BUILDING MODELS

Vestnik Tomskogo gosudarstvennogo arkhitekturno-stroitel nogo universiteta JOURNAL of Construction and Architecture ◽

10.31675/1607-1859-2019-21-5-138-150 ◽

2019 ◽

Vol 21 (5) ◽

pp. 138-150

Author(s):

S. V. Korobkov ◽

A. I. Gnyrya ◽

V. I. Terekhov

Keyword(s):

Heat Exchange ◽

Mutual Effect ◽

Convective Heat Exchange ◽

Physical Models ◽

Interference Effects ◽

Total Contribution ◽

Heat Flows ◽

Building Models ◽

Number Of Factors ◽

Thermal Interference

The paper considers the dynamic and thermal interference effects on two neighbouring building models in the form of square prisms arranged at a short distance from each other. It is shown how relative positions of the models affect the specific phenomena caused by the airflow interactions.The aim of this paper is to experimentally study the dynamic and thermal interference of a tandem of two building models in the form of square prisms depending on their relative position.The phenomenon of wind loads on buildings and structures has always attracted great interest among engineers and researchers. With the accumulation of knowledge and technical capabilities, the potential for likely ways to study wind flows and their impact on different objects increased. In recent years, the world science has accumulated an extensive knowledge base on wind impacts on objects of various shapes, such as prisms, pyramids, cylinders, etc. Studies are carried out for their mutual impact of several objects on changes in both the wind load and heat exchange. Their mutual effect on the air motion and turbulence is considered.There are two main areas in the field of the wind impact. The first impact is the force load on building, the second is the wind as a source of convective heat exchange. The object of this study is the interference parameters allowing to assess the influence on the field of pressure and heat recoil of disturbances evoked in front of the barriers.At the first stage, physical models help to study the pressure field on different facets and ratios of the local and medium heat exchange under the forced convection conditions. The next step is to jointly consider the wind (dynamic) load and heat flows, attempting to detect the total contribution to changes depending on the reciprocal model arrangement. All experiments are performed in the aerodynamic tube, at the TSUAB department. It is shown that the dynamic and thermal interference ratios vary greatly in two building models. At the same time, the thermal interference is very conservative compared to the dynamic. Using the interference parameters, it is easy to analyze the extreme pressure and the heat flow on the model surface depending on a large number of factors, including their arrangement.

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CHEMICAL PULPING. Oxidative degradation of AOX in softwood-based kraft mill effluents from E C F bleachin g

Nordic Pulp & Paper Research Journal ◽

10.3183/npprj-2012-27-04-p707-713 ◽

2012 ◽

Vol 27 (4) ◽

pp. 707-713 ◽

Cited By ~ 1

Author(s):

Jukka Pekka lsoaho ◽

Suvi Tarkkanen ◽

Raimo Alen ◽

Juha Fiskari

Keyword(s):

Reaction Time ◽

Oxidative Degradation ◽

Cost Effective ◽

Process Conditions ◽

Main Process ◽

Chemical Pulping ◽

Kraft Mill ◽

Organic Halogens ◽

Aox Removal ◽

Adsorbable Organic Halogens

Abstract Softwood-based kraft mill bleaching effluents from the initial bleaching stages D0 and E1 (the bleaching sequence being D0E 1D 1 E2D2) were treated by the oxidative Fenton method (H20rFeS04) to decompose organic pollutants contammg adsorbable organic halogens (AOX). Experiments designed using the Taguchi method were applied to predict the process conditions that would result in a cost-effective and adequate removal of AOX. In addition to the composition and concentration of the reagents (H202 and Fe2+), the main process parameters selected were temperature and reaction time, while pH was adj usted to an approximate value of 4 (the volumetric ratio of the mixed effluents D0:E 1 was 3 :2). The results indicated that an AOX removal of about 70% for this mixture ( corresponding to about 50% for the mill) was achieved when the eftluent samples were treated for 60 min at 70°C with H202 and Fe2+ at a concentration of 1 600 mg/1 and 28 mg/1, respectively.

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