152 research outputs found
Психолого-педагогічні умови формування просоціальної поведінки у дітей молодшого шкільного віку
(uk) У статті формування просоціальної поведінки розглядається як керована соціалізація особистості, проаналізовані передумови розгляду питання щодо стадіальності становлення просоціальної поведінки в онтогенезі. Обґрунтовані та систематизовані психолого-педагогічні умови, що прискорюють процес формування суспільно корисної поведінки в молодшому шкільному віці.(ru) В статье формирования просоциального поведения рассматривается как управляемая социализация личности, проанализированы предпосылки рассмотрения вопроса о стадиальности становления просоциального поведения в онтогенезе. Обоснованы и систематизированы психолого-педагогические условия, которые могут ускорить процес формирования общественно полезного поведения в младшем школьном возрасте
Charge Carrier Extraction by Linearly Increasing Voltage:Analytic framework and ambipolar transients
Up to now the basic theoretical description of charge extraction by linearly
increasing voltage (CELIV) is solved for a low conductivity approximation only.
Here we present the full analytical solution, thus generalize the theoretical
framework for this method. We compare the analytical solution and the
approximated theory, showing that especially for typical organic solar cell
materials the latter approach has a very limited validity. Photo-CELIV
measurements on poly(3-hexyl thiophene-2,5-diyl):[6,6]-phenyl-C61 butyric acid
methyl ester based solar cells were then evaluated by fitting the current
transients to the analytical solution. We found that the fit results are in a
very good agreement with the experimental observations, if ambipolar transport
is taken into account, the origin of which we will discuss. Furthermore we
present parametric equations for the mobility and the charge carrier density,
which can be applied over the entire experimental range of parameters.Comment: 8 pages, 5 figure
Charge Transport in Pure and Mixed Phases in Organic Solar Cells
In organic solar cells continuous donor and acceptor networks are consid-
ered necessary for charge extraction, whereas discontinuous neat phases
and molecularly mixed donor–acceptor phases are generally regarded as detrimental. However, the impact of different levels of domain continuity, purity, and donor–acceptor mixing on charge transport remains only semi- quantitatively described. Here, cosublimed donor–acceptor mixtures, where the distance between the donor sites is varied in a controlled manner from homogeneously diluted donor sites to a continuous donor network are studied. Using transient measurements, spanning from sub-picoseconds to micro- seconds photogenerated charge motion is measured in complete photovoltaic devices, to show that even highly diluted donor sites (5.7%–10% molar) in a buckminsterfullerene matrix enable hole transport. Hopping between isolated donor sites can occur by long-range hole tunneling through several buckmin- sterfullerene molecules, over distances of up to ≈4 nm. Hence, these results question the relevance of “pristine” phases and whether a continuous interpen- etrating donor–acceptor network is the ideal morphology for charge transport
Photovoltaic devices based on photo induced charge transfer in polythiophene: CN-PPV blends
White light from an electroluminescent diode made from poly[3(4‐octylphenyl)‐2,2’‐bithiophene] and an oxadiazole derivative
Prognostic value of p53 gene mutations in a large series of node- negative breast cancer patients
The most important subgroup of breast cancer patients for which reliable prognostic factors are needed are women without axillary lymph node involvement. Although overall, these patients have a good prognosis, it is known that 20-30% will experience a recurrence of the disease. To determine the prognostic significance of P53 tumor suppressor gene mutation, specimens from 113 primary breast cancers were evaluated for the presence of P53 alterations, as detected by cDNA sequencing of the entire coding sequence of the gene. The median follow-up for patients was 105 months. P53 gene mutation was an independent prognostic marker of early relapse and death. Our results suggest that P53 gene mutations could be an important factor to identify node-negative patients who have a poor prognosis in the absence of adjuvant therapy. Prospective studies should be designed to determine which therapy should be performed in this subgroup of patients
Competition between the Charge Transfer State and the Singlet States of Donor or Acceptor Limiting the Efficiency in Polymer:Fullerene Solar Cells
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