排序方式: 共有136条查询结果,搜索用时 18 毫秒
51.
The electron paramagnetic resonance (EPR) of γ-irradiated powders of l-(+)-tartaric acid, N-acetyl-l-alanine and 1-methyl-l-histidine were investigated at room temperature. Radiation damage centers are attributed to HOOCCH(OH)?(OH)COOH, CH3?HCOOH and ?CH2?HCOOH radicals. The spectra were computer-simulated. Hyperfine structure constants and g-values were determined for these three radicals. The unirradiated samples showed no EPR signal. Some spectroscopic properties and suggestions concerning the possible structure of the radicals are discussed in this paper. 相似文献
52.
M. Ayd?n B. Esat Ç. K?l?ç M.E. Köse A. Ata F. Y?lmaz 《European Polymer Journal》2011,47(12):2283-2294
A polythiophene derivative bearing TEMPO radical was synthesized by oxidative chemical polymerization of its monomer. The polymer had a high spin density (2.05 × 1021 spins/g of polymer). CV studies of the polymer showed that the electrochemical redox reaction of the TEMPO radicals were completely reversible. We demonstrated, for the first time, construction and charge/discharge characteristics of an organic radical battery utilizing a TEMPO bearing polythiophene based cathode material. The battery had an initial specific discharge capacity of 79 A h/kg (87% of the theoretical capacity) and an average output voltage of 3.6 V. The specific energy capacity initially discharged was 268 W h/kg. 相似文献
53.
Duygu Ayd?n Tekda?Ufuk Kumru Ay?e Gül GürekMahmut Durmu? Vefa Ahsen Fabienne Dumoulin 《Tetrahedron letters》2012,53(39):5227-5230
A Zn(II) phthalocyanine substituted with eight hydroxylated sulfanyl moieties in non-peripheral positions was designed to exhibit properties desired for photodynamic therapy: hydrophilicity, isomeric purity and near-infrared absorption in addition to high singlet oxygen generation. Photophysical and photochemical studies proved to be promising. 相似文献
54.
The effects of W doping on the characteristical properties of SnO2 thin films prepared by sol–gel spin coating method were investigated. The SnO2 thin films were deposited at various W doping ratios and characterized by various measurements. XRD studies indicated that the undoped and W doped SnO2 films had cubic and tetragonal phases. The SEM images of WTO thin films showed cubic shaped nanocubes corresponding to cubic phase and the smaller particles corresponding to tetragonal phase were formed on the film surfaces, and their distributions and sizes were dependent on the W doping ratio. EDX spectroscopy analyses showed that the calculated and participated atomic ratios of W/(W + Sn) (at.%) in the starting solution and in the WTO thin films were almost close. It was found that the sheet resistance depended on W doping ratio and 2.0 at.% W doped SnO2 (WTO) exhibited lowest value of sheet resistance (7.11 × 103 Ω/cm2). 相似文献
55.
In this paper we obtain new conditions for the global existence and boundedness of solutions for nonlinear second-order equations of the form where is a real constant. The results are applicable to well-known Emden–Fowler and Lienard type equations. An illustrative example is also provided. 相似文献
56.
Dominant sets based movie scene detection 总被引:1,自引:0,他引:1
Multimedia indexing and retrieval has become a challenging topic in organizing huge amount of multimedia data. This problem is not a trivial task for large visual databases; hence, segmentation into low- and high-level temporal video segments might improve the realization of this task. In this paper, we introduce a weighted undirected graph-based movie scene detection approach to detect semantically meaningful temporal video segments. The method is based on the idea of finding the dominant scene of the video according to the selected low-level feature. The proposed method starts from obtaining the most reliable solution first and exploit each solution in the subsequent steps recursively. The dominant movie scene boundary, which can be the highest probability to be the correct one, is determined and this scene boundary information is also exploited in the subsequent steps. We handle two partitioning strategies to determine the boundaries of the remaining scenes. One is a tree-based strategy and the other is an order-based strategy. The proposed dominant sets based movie scene detection method is compared with the graph-based video scene detection methods presented in literature. 相似文献
57.
Sezgin Bakırdere Selin Bora E. Gülhan Bakırdere Fırat Aydın Yasin Arslan O. Tarık Komesli Işıl Aydın Emrah Yıldırım 《Central European Journal of Chemistry》2012,10(3):675-685
Carcinogenic and mutagenic properties of aflatoxin species are known in literature. Their intake over a long time period might
be health-dangerous for human even at trace levels. It is well known that different foodstuffs can be contaminated by aflatoxin
species through growing and storage. Due to the serious health effects, sensitive determination of aflatoxin species in any
matrices related with the human being is very crucial at trace levels. In literature, there are sensitive techniques to analyze
the different samples for the contents of their aflatoxin species. Each technique has some advantages and disadvantages over
the other techniques. This review aims to summarize the different health effects of aflatoxin species, development of analytical
techniques and applications of developed techniques in a variety of matrices.
相似文献
58.
Al-Jibori Subhi A. Ulghafoor Mustafa A. Karadağ Ahmet Aydın Ali Akbaş Hüseyin Ruiz Santiago G. 《Transition Metal Chemistry》2019,44(6):575-583
Transition Metal Chemistry - Reaction of Na2[PdCl4] with two equivalents of 4,5-benzo-3H-1,2-dithiole-3-thione (btt) affords cis-[PdCl2(κ1-btt)2] (1), which provides a convenient entry into... 相似文献
59.
The Gross-Pitaevskii equation, which is the governor equation of Bose-Einstein condensates, is solved by first order perturbation expansion under various q-deformed potentials. Stationary probability distributions reveal one and two soliton behavior depending on the type of the q-deformed potential. Additionally a spatial shift of the probability distribution is found for the dark soliton solution, when the q parameter is changed. 相似文献
60.