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91.
Arne Kolberg Sabine Kirrbach Dagmar Selke Brbel Schulze Svetlana Morozkina 《Advanced Synthesis \u0026amp; Catalysis》2000,342(3):291-296
The oxidation of isothiazolium 2‐imines 3,5 and their salts 4 to stable 3‐hydroperoxy‐2,3,4,5,6,7‐hexahydro‐1,2‐benzisothiazole 1‐oxides 7 and 1,1‐dioxides 8 and 9 as a new class of cyclic sultims and sultams is described. The formation of 3‐hydroxysultams 10 and isothiazol‐3(2H)one 1,1‐dioxides 11 is presented. 相似文献
92.
Petr Svoboda Rajesh Theravalappil Sameepa Poongavalappil Jarmila Vilcakova Dagmar Svobodova Pavel Mokrejs Antonin Blaha 《Polymer Engineering and Science》2012,52(6):1241-1249
A series of ethylene–octene copolymer (EOC) composites have been prepared by melt‐mixing with different weight ratios of expandable graphite filler (0–50% by weight). Electrical conductivity [both alternating current (AC) and direct current (DC)] and thermal conductivity studies were carried out. Effect of filler loading and frequency on electrical conductivity was studied. DC conductivity has increased from 1.51 × 10?13 S cm?1 to 1.17 × 10?1 S cm?1. Percolation threshold by DC and also AC methods was observed at about 16 vol% of the filler. Real part of permittivity was found to be decreasing with increase in frequency while conductivity was increasing. Thermal conductivity was also found to be increasing gradually from 0.196 to 0.676 Wm?1 K?1 which is about 245% increase. Graphite not only increases the electrical and thermal conductivities but at and above 40 wt%, also acts as a halogen‐free, environmental friendly flame retardant. Shore‐A hardness of EOC/graphite composites shows that even with high graphite loading, the hardness is increased from about 50–68 only so that the rubbery nature of the composite is not affected very much. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers 相似文献
93.
Martaus J Cambel V Gregusová D Kúdela R Fedor J 《Journal of nanoscience and nanotechnology》2010,10(7):4448-4453
A novel approach to local anodic oxidation technique, which leads to approximately equal 50 nm wide line patterns, is described. The technique is utilized to prepare quantum point contact on a low-mobility semiconductor heterostructure. Transport measurements show quantized conductance in zero magnetic field at 4.2 K thanks to very short one-dimensional constriction. The technique is also used for the definition of low-to-room temperature sub-micrometer Hall probes to show its applicability for the room temperature applications. The magnetic-field resolution and the sensitivity of the probes are evaluated in dependence of the probe dimensions, bias current, and temperature. The 200-nm probe shows magnetic-field resolution of 47 microT/(Hz)(1/2) at 140 Hz and at 4.2 K, when it is driven by 5 microA bias current. The novel approach is promising for the development of the future nano-devices operated both at low and room temperatures. To our knowledge, local anodic oxidation technique applied directly to shallow semiconductor heterostructure has been successfully used for the room temperature application for the first time. 相似文献
94.
Exemplar sequencing effects in incidental and intentional unsupervised category learning were investigated to illuminate how people form categories without an external teacher. Stimuli were perfectly separable into 2 categories based on 1 of 2 dimensions of variation. Sequencing of the first 20 training stimuli was manipulated. In the blocked condition, 10 Category A stimuli were followed by 10 Category B stimuli. In the intermixed condition, these 20 stimuli were ordered randomly. Experiment 1 revealed an interaction between learning mode and sequence, with better intentional learning for intermixed sequences but better incidental learning for blocked sequences. Experiment 2 showed that manipulating trial-to-trial variability along each dimension can impact intentional learning. Training sequences that emphasized variation along the category-relevant dimension resulted in better performance than sequences that emphasized variation along the category-irrelevant dimension. The results suggest that unsupervised category learning is influenced by the mode of learning and the order and nature of encountered exemplars. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
The role of phase-transfer catalysts (PTC) (ammonium and phosphonium salts) with various anions on the biphasic oxidative cleavage of long chain olefins with aqueous hydrogen peroxide catalyzed by Na2WO4/H3PO4/PTC system has been investigated. It was shown that the nature of PTC widely affects the catalytic activity of the above system in the conversion of alkenes, cycloalkenes and unsaturated fatty acids into carboxylic acids. 相似文献
96.
The role of phase-transfer catalysts (PTC) (ammonium and phosphonium salts) with various anions on the biphasic oxidative cleavage of long chain olefins with aqueous hydrogen peroxide catalyzed by Na2WO4/H3PO4/PTC system has been investigated. It was shown that the nature of PTC widely affects the catalytic activity of the above system in the conversion of alkenes, cycloalkenes and unsaturated fatty acids into carboxylic acids.
相似文献97.
Maass Anne; Milesi Angela; Zabbini Silvia; Stahlberg Dagmar 《Canadian Metallurgical Quarterly》1995,68(1):116
The linguistic intergroup bias describes the tendency to communicate positive in-group and negative out-group behaviors more abstractly than negative in-group and positive out-group behaviors. This article investigated whether this bias is driven by differential expectancies or by in-group protective motives. In Exp 1, northern and southern Italian participants (N?=?151) described positive and negative behaviors of northern or southern protagonists that were either congruent or incongruent with stereotypic expectancies. Regardless of valence, expectancy-congruent behaviors were described more abstractly than incongruent ones. Exp 2 (N?=?40) showed that language is used in an equally biased fashion for individuals as previously demonstrated for groups. Exp 3 (N?=?192) induced expectancies experimentally and found greater abstraction for expectancy-congruent behaviors regardless of valence. All experiments confirmed the differential expectancy approach. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
Alena Nprstkov Kateina Malínsk Lenka Zvesk Drbkov Elodie Billey Dagmar Nprstkov Eva Sýkorov Ccile Bousquet-Antonelli David Honys 《International journal of molecular sciences》2021,22(4)
ALBA DNA/RNA-binding proteins form an ancient family, which in eukaryotes diversified into two Rpp25-like and Rpp20-like subfamilies. In most studied model organisms, their function remains unclear, but they are usually associated with RNA metabolism, mRNA translatability and stress response. In plants, the enriched number of ALBA family members remains poorly understood. Here, we studied ALBA dynamics during reproductive development in Arabidopsis at the levels of gene expression and protein localization, both under standard conditions and following heat stress. In generative tissues, ALBA proteins showed the strongest signal in mature pollen where they localized predominantly in cytoplasmic foci, particularly in regions surrounding the vegetative nucleus and sperm cells. Finally, we demonstrated the involvement of two Rpp25-like subfamily members ALBA4 and ALBA6 in RNA metabolism in mature pollen supported by their co-localization with poly(A)-binding protein 3 (PABP3). Collectively, we demonstrated the engagement of ALBA proteins in male reproductive development and the heat stress response, highlighting the involvement of ALBA4 and ALBA6 in RNA metabolism, storage and/or translational control in pollen upon heat stress. Such dynamic re-localization of ALBA proteins in a controlled, developmentally and environmentally regulated manner, likely reflects not only their redundancy but also their possible functional diversification in plants. 相似文献
99.
100.
Babčanová Dagmar Šujanová Jana Cagáňová Dagmar Horňáková Natália Hrablik Chovanová Henrieta 《Wireless Networks》2021,27(3):1693-1700
Wireless Networks - The purpose of the paper is to point out the importance of analysing data obtained from social media through the qualitative data analysis software. The main goal of conducted... 相似文献