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41.
42.
Petr Zimcik Miroslav Miletin Veronika Novakova Kamil Kopecky Zuzana Dvorakova 《Dyes and Pigments》2009,81(1):35-39
Zinc tetrapyrazinoporphyrazines comprising different numbers of pyridin-2-yl and tert-butylsulfanyl substituents were prepared by the statistical condensation of two precursors – 5,6-bis(tert-butylsulfanyl)pyrazine-2,3-dicarbonitrile (A) and 5,6-dipyridin-2-yl-pyrazine-2,3-dicarbonitrile (B). The ensuing zinc tetrapyrazinoporphyrazines were chromatographically separated on silica column and characterized. Adjacent (AABB) and opposite (ABAB) isomers were not separated. The prepared zinc tetrapyrazinoporphyrazines did not differ in their Q-band position but the B-band position was shifted hypsochromically for compounds bearing more pyridyl units; in addition, a weak band at 450–520 nm decreased with increasing number of pyridyl substituents. Singlet oxygen quantum yields (ΦΔ in the range 0.69–0.53) decreased with increasing number of pyridyl units on the macrocyclic core, while fluorescence quantum yields showed the reverse tendency (ΦF in the range 0.22–0.26). 相似文献
43.
Michal Hoznedl Ladislav Tajc Jaroslav Krejcik Lukas Bednar Kamil Sedlak Jiri Linhart 《Frontiers of Energy and Power Engineering in China》2009,3(3):321-329
In the past, increased attention was given to the development of an optimal shape for the inlet part of LP turbine casings
in SKODA POWER. A double-flow design is typically used for high power output turbines. An optimized shape for the internal
diffuser has been found, which transforms the kinetic energy of steam into increased pressure, thus effectively increasing
the thermodynamic efficiency of the stage. Some conclusions have been drawn from laboratory experiments, others derived directly
from on-site measurements at power plants. The conclusions from the development of double-flow turbines form the basis for
the design of the single-flow turbine arrangement. Single-flow design is typically used for lower output turbines. There are
still some limitations in applying this arrangement. The designer needs to resolve the bearing position and how to ensure
access to them. Reinforcing the ribs and supports are used, therefore, to ensure the rigidity of the entire casing. The optimization
of the single-flow diffuser shape is therefore the subject of the study presented below. 相似文献
44.
In these experiments, the authors examined the nature of the spatial information that Clark's nutcrackers. (Nucifraga columbiana) use during navigation and whether this information is represented in the form of a cognitive map. In Experiment 1, nutcrackers were able to use distal cues to locate a small hidden goal. In Experiments 2 and 3, nutcrackers were given the opportunity to develop a map of a room by viewing local subsets of the landmarks in the room at a goal during training. During transfer tests, nutcrackers were presented with a landmark panorama that was not previously seen at the goal. Of 3 nutcrackers that had learned the relationship between distal cues and the goal, 3 were able to locate the goal during transfer, indicating they may have developed a cognitive map. Experiments 4 and 5 suggest that the simpler mechanism of vector integration may have been used by some nutcrackers during the transfer tests. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
Zdeněk Sobalík Kamil Jíša Dalibor Kaucký Alena Vondrová Zdeňka Tvarůžková Jana Nováková 《Catalysis Letters》2007,113(3-4):124-129
The decomposition of nitrous oxide was studied over Fe-ferrierite, Me-ferrierites and Fe/Me-ferrierites (Me: Pt, Rh and Ru).
Flow as well as batch experiments were carried out and showed a synergy between Fe and Me ions. Ions of noble metals in Fe-ferrierite
increased the catalytic activity in the sequence Pt < Rh ≅ Ru. Addition of NO substantially decreased the decomposition of
N2O over Rh/ferrierite and Ru/ferrierite, but not over bimetallic ferrierites. NO
x
species created during the decomposition of nitrous oxide alone as well as with addition of NO, and employment of nitrous
oxide labeled with 18O allowed us to assume a changing decomposition mechanism in the presence of Me ions in Fe-ferrierites. 相似文献
46.
47.
Hyoung Eun Bae Prof. Kamil Gotfryd Jennifer Thomas Hazrat Hussain Muhammad Ehsan Juyeon Go Prof. Claus J. Loland Dr. Bernadette Byrne Prof. Pil Seok Chae 《Chembiochem : a European journal of chemical biology》2015,16(10):1454-1459
Detergents are an absolute requirement for studying the structure of membrane proteins. However, many conventional detergents fail to stabilise denaturation‐sensitive membrane proteins, such as eukaryotic proteins and membrane protein complexes. New amphipathic agents with enhanced efficacy in stabilising membrane proteins will be helpful in overcoming the barriers to studying membrane protein structures. We have prepared a number of deoxycholate‐based amphiphiles with carbohydrate head groups, designated deoxycholate‐based glycosides (DCGs). These DCGs are the hydrophilic variants of previously reported deoxycholate‐based N‐oxides (DCAOs). Membrane proteins in these agents, particularly the branched diglucoside‐bearing amphiphiles DCG‐1 and DCG‐2, displayed favourable behaviour compared to previously reported parent compounds (DCAOs) and conventional detergents (LDAO and DDM). Given their excellent properties, these agents should have significant potential for membrane protein studies. 相似文献
48.
The dielectric properties of corn seeds were determined in the ranges of 9.71-21.51% wet basis (w.b.) for moisture content, 772.5-902.2 kg/m3 for bulk density and 1-100 MHz for frequency of applied electric field using a coaxial capacitor sample holder. Effects of the parameters such as moisture content, bulk density and frequency on the dielectric properties were investigated. The dielectric constant, loss factor and loss tangent were greatly affected by the moisture content, frequency and bulk density. The moisture content was the most significant factor affecting the dielectric properties of corn seeds. The dielectric constant, loss factor and loss tangent increased with increasing moisture content and bulk density. The second and third-order polynomial equations were proposed to describe the existing relationship between dielectric properties and moisture content. Dielectric measurements provided new information concerning moisture content and bulk density dependent behaviour of dielectric properties of corn seeds that may be useful in sensing of the moisture content. 相似文献
49.
Firouz FADAEIFARD Khamirul Amin MATORI Meysam TOOZANDEHJANI Abdul Razak DAUD Mohd Khairol Anuar Mohd ARIFFIN Norinsan Kamil OTHMAN Farhad GHARAVI Abdul Hadi RAMZANI Farhad OSTOVAN 《中国有色金属学会会刊》2014,24(4):1004-1011
采用场发射扫描电子显微镜(FE-SEM),研究转速对厚度为5 mm的6061-T6铝合金搅拌摩擦搭接焊接头的宏观和微观组织、硬度、搭接头剪切性能和失效模式的影响。结果表明:在最低的转速度下,上模板和下模板具有十分相似的硬度分布。采用EDX分析发现,焊核区的断裂面中含有Fe的化合物。 相似文献
50.
Aneta Wgierek-Ciuk Micha Arabski Karol Ciepluch Kamil Brzska Halina Lisowska Malwina Czerwiska Tomasz Stpkowski Krzysztof Lis Anna Lankoff 《International journal of molecular sciences》2021,22(11)
Coralyne is a synthetic analog of berberine related to protoberberine-isoquinoline alkaloids. Isoquinoline derivatives and analogs are renowned as potent radiosensitizers with potential medical application. In the present study, we investigated the effect of coralyne on the cell death, cytoskeletal changes and cell cycle progression of irradiated A549 cells. A clonogenic assay revealed that coralyne pretreatment decreased the viability of A549 cells in a time- and dose-dependent manner. Moreover, exposure to coralyne and ionizing radiation (IR) markedly altered the filamentous actin cytoskeletal architecture and integrin-β binding sites of A549 cells. Treatment with 1–25 µM coralyne in combination with 2 Gy of IR significantly reduced the percentage of cells in G2/M phase compared with 2 Gy IR alone. These results indicate that coralyne is a potent radiosensitizing agent that may find an application in medicine. 相似文献