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Plasma-Chemical Synthesis of Nanosized Powders-Nitrides,Carbides,Oxides,Carbon Nanotubes and Fullerenes

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Plasma Science and Technology 2012年第11期14卷 980-995页

作者： katerina ZAHARIEVA Gheorghi VISSOKOV Janis GRABIS Slavcho RAKOVSKY Institute of Catalysis Bulgarian Academy of Sciences Institute of Inorganic Chemistry Riga Technical University

In this article the plasma-chemical synthesis of nanosized powders （nitrides, car- bides, oxides, carbon nanotubes and fullerenes） is reviewed. Nanosized powders - nitrides, carbides, oxides, carbon nanotubes and fullerenes have been successfully produced using different techniques, technological apparatuses and conditions for their plasma-chemical synthesis.

关键词： plasma nanosized powders nitrides carbides oxides carbon nanotubes,fullerenes

Bright trions in direct-bandgap silicon nanocrystals revealed by low-temperature single-nanocrystal spectroscopy

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Light(Science & Applications) 2015年第1期4卷 179-186页

作者： katerina Kusova Ivan Pelant Jan Valenta Institute of Physics of the ASCR v.v.i.Cukrovarnicka 1016200 Prague 6Czech Republic Faculty of Mathematics and Physics Charles UniversityKe Karlovu 512116 Prague 2Czech Republic

Strain-engineered silicon nanocrystals(SiNCs)have recently been shown to possess direct ***,we report the observation of a rich structure in the single-nanocrystal photoluminescence spectra of strain-engineered direct-bandgap SiNCs in the temperature range of 9–300 *** relationship between individual types of spectra is discussed,and the numerical modeling of spectral diffusion of the experimentally acquired spectra reveals a common origin for most *** intrinsic spectral shape is shown to be a structure that contains three peaks,approximately 150 meV apart,each of which possesses a Si phonon *** spectral lines,reaching ≤ meV at 20 K,are *** observed temperature dependence of the spectral structure can be assigned to the radiative recombination of positively charged trions,in contrast to several previous reports linking a very similar shape to phonons in the surface capping *** result serves as strong additional support for the direct-bandgap nature of the investigated SiNCs.

关键词： direct bandgap low-temperature single-nanocrystal spectroscopy silicon nanocrystals trions

Fiber-Optic Sensor Applications in Civil and Geotechnical Engineering

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Photonic Sensors 2011年第3期1卷 268-280页

作者： Wolfgang R. HABEL and katerina KREBBER Federal Institute for Materials Research and Testing Division VIII. 1: Measurement and Testing Technology Sensors D-12205 Berlin Germany

Different types of fiber-optic sensors based on glass or polymeric fibers are used to evaluate material behavior or to monitor the integrity and long-term stability of load-bearing structure components. Fiber-optic sensors have been established as a new and innovative measurement technology in very different fields, such as material science, civil engineering, light-weight structures, geotechnical areas as well as chemical and high-voltage substations. Very often, mechanical quantities such as deformation, strain or vibration are requested. However, measurement of chemical quantities in materials and structure components, such as pH value in steel reinforced concrete members also provides information about the integrity of concrete structures. A special fiber-optic chemical sensor for monitoring the alkaline state （pH value） of the cementitious matrix in steel-reinforced concrete structures with the purpose of early detection of corrosion-initiating factors is described. The paper presents the use of several fiber-optic sensor technologies in engineering. One example concerns the use of highly resolving concrete-embeddable fiber Fabry-Perot acoustic emission （AE） sensors for the assessment of the bearing behaviour of large concrete piles in existing foundations or during and after its installation. Another example concerns fiber Bragg grating （FBG） sensors attached to anchor steels （micro piles） to measure the strain distribution in loaded soil anchors. Polymer optical fibers （POF） can be -- because of their high elasticity and high ultimate strain - well integrated into textiles to monitor their deformation behaviour. Such ＂intelligent＂ textiles are capable of monitoring displacement of soil or slopes, critical mechanical deformation in geotechnical structures （dikes, dams, and embankments） as well as in masonry structures during and after earthquakes.

关键词： Fiber-optic sensor monitoring earthquake damage assessment steel-reinforced structures pH sensor geotextiles distributed sensor

NORMA:The Network Makeup Artist—A Web Tool for Network Annotation Visualization

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Genomics, Proteomics & Bioinformatics 2022年第3期20卷 578-586页

作者： Mikaela Koutrouli Evangelos Karatzas katerina Papanikolopoulou Georgios A.Pavlopoulos Institute for Fundamental Biomedical Research BSRC“Alexander Fleming”Vari 16672Greece Department of Informatics and Telecommunications University of AthensAthens 15703Greece

The Network Makeup Artist(NORMA) is a web tool for interactive network annotation visualization and topological analysis, able to handle multiple networks and annotations simultaneously. Precalculated annotations(e.g., Gene Ontology, Pathway enrichment, community detection,or clustering results) can be uploaded and visualized in a network, either as colored pie-chart nodes or as color-filled areas in a 2D/3D Venn-diagram-like style. In the case where no annotation exists,algorithms for automated community detection are offered. Users can adjust the network views using standard layout algorithms or allow NORMA to slightly modify them for visually better group separation. Once a network view is set, users can interactively select and highlight any group of interest in order to generate publication-ready figures. Briefy, with NORMA, users can encode three types of information simultaneously. These are 1) the network, 2) the communities or annotations of interest, and 3) node categories or expression values. Finally, NORMA offers basic topological analysis and direct topological comparison across any of the selected networks. NORMA service is available at http://***, whereas the code is available at https://***/Pavlopoulos Lab/NORMA.

关键词： Network annotation Visualization Topological analysis Community detection Functional enrichment visualization

Investigating the coagulation of non-proteinaceous algal organic matter: Optimizing coagulation performance and identification of removal mechanisms

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Journal of Environmental Sciences 2019年第5期31卷 25-34页

作者： Jana Naceradska katerina Novotna Lenka Cermakova Tomas Cajthaml Martin Pivokonsky Institute of Hydrodynamics of the Czech Academy of Sciences Institute of Microbiology of the Czech Academy of Sciences

The removal of algal organic matter(AOM) is a growing concern for the water treatment industry worldwide. The current study investigates coagulation of non-proteinaceous AOM(AOM after protein separation), which has been minimally explored compared with proteinaceous fractions. Jar tests with either aluminum sulphate(alum) or polyaluminium chloride(PACl) were performed at doses of 0.2–3.0 mg Al per 1 mg of dissolved organic carbon in the p H range 3.0–10.5. Additionally, non-proteinaceous matter was characterized in terms of charge, molecular weight and carbohydrate content to assess the treatability of its different fractions. Results showed that only up to 25% of non-proteinaceous AOM can be removed by coagulation under optimized conditions. The optimal coagulation p H(6.6–8.0 for alum and 7.5–9.0 for PACl) and low surface charge of the removed fraction indicated that the prevailing coagulation mechanism was adsorption of non-proteinaceous matter onto aluminum hydroxide precipitates. The lowest residual Al concentrations were achieved in very narrow p H ranges, especially in the case of PACl. High-molecular weight saccharidelike organics were amenable to coagulation compared to low-molecular weight(< 3 k Da)substances. Their high content in non-proteinaceous matter(about 67%) was the reason for its low removal. Comparison with our previous studies implies that proteinaceous and nonproteinaceous matter is coagulated under different conditions due to the employment of diverse coagulation mechanisms. The study suggests that further research should focus on the removal of low-molecular weight AOM, reluctant to coagulate, with other treatment processes to minimize its detrimental effect on water safety.

关键词： Algal organic matter Chlorella vulgaris Coagulation Flocculation Non-proteinaceous matter Water treatment

The Effect of Family Background and Parental Expectations on Eighth Graders’Academic Achievement in Rural and Urban China

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Frontiers of Education in China 2020年第4期15卷 647-677页

作者： Jiehui ZHAO katerina BODOVSKI College of Education University of MarylandCollege ParkMD 20742USA Department of Education Policy Studies The Pennsylvania State UniversityUniversity ParkPA 16802USA

Extensive research has suggested that there is a large rural-urban student achievement gap in ***,less is known about the effects of family background and parental expectations on student *** a large representative sample of Chinese eighth graders,this study examines these *** find that:(1)Rather than a rural/urban hukou(household registration system)type,it is variation in family background,especially family socioeconomic status(SES),which plays a significant role in student achievement;(2)although factors of family background show different patterns of influence on Chinese,mathematics,and English achievement,maternal education and home educational resources are significantly positive predictors consistently across three subjects;(3)parental expectations are significantly and positively associated with Chinese,mathematics,and English achievement.

关键词： middle school students achievement gap socioeconomic status hukou parental expectations rural-urban China

Evaluating grant proposals:lessons from using metrics as screening device

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数据与情报科学学报:英文版 2023年第2期8卷 66-92页

作者： katerina Guba Alexey Zheleznov Elena Chechik Center for Institutional Analysis of Science and Education European University at Saint PetersburgGagarinskaya 6/1A Saint Petersburg 191178Russian Federation

Purpose:This study examines the effects of using publication-based metrics for the initial screening in the application process for a project *** key questions are whether formal policy affects the allocation of funds to researchers with a better publication record and how the previous academic performance of principal investigators is related to future project ***/methodology/approach:We compared two competitions,before and after the policy raised the publication threshold for the principal *** analyzed 9,167 papers published by 332 winners in physics and the social sciences and humanities(SSH),and 11,253 publications resulting from each funded ***:We found that among physicists,even in the first period,grants tended to be allocated to prolific authors publishing in high-quality *** contrast,the SSH project grantees had been less prolific in publishing internationally in both periods;however,in the second period,the selection of grant recipients yielded better results regarding awarding grants to more productive authors in terms of the quantity and quality of *** was no evidence that this better selection of grant recipients resulted in better publication records during grant ***:This study contributes to the discussion of formal policies that rely on metrics for the evaluation of grant *** Russian case shows that such policy may have a profound effect on changing the supply side of applicants,especially in disciplines that are less suitable for metric-based *** spite of the criticism given to metrics,they might be a useful additional instrument in academic systems where professional expertise is corrupted and prevents allocation of funds to prolific researchers.

关键词： Grant funding Research evaluation Publication-based metrics Funding allocation

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JIC总部设计

现代装饰 2024年第3期 78-85页

作者： Tomas Kozelsky(设计) Viktor Odstrcilik(设计) Alexandra Georgescu(设计) katerina Batkova(设计) Tana Kantor(设计) Marketa Fiserova(设计) Josef Rehak(设计) Natalie Hradilikova(设计) BoysPlayNice(摄影) 舒禹(编译) 不详

捷克建筑工作室KOGAA与南摩拉维亚创新中心(JIC)共同完成了其位于布尔诺的第二个改造项目,JIC作为支持该地区企业的重要开放创新生态系统,为学生、初创企业、规模化企业和老牌企业提供空间和支持服务。疫情期间和之后,工作模式发生变化... 详细信息

捷克建筑工作室KOGAA与南摩拉维亚创新中心(JIC)共同完成了其位于布尔诺的第二个改造项目,JIC作为支持该地区企业的重要开放创新生态系统,为学生、初创企业、规模化企业和老牌企业提供空间和支持服务。疫情期间和之后,工作模式发生变化,更趋向开放和协作。因此,原先的固定结构布局已过时,作为另类改造工作空间的专家,KOGAA被要求为办公室提出一个新的愿景,以促进协作,激活创造力,为新的公司结构寻找可持续的解决方案。

关键词：创新生态系统初创企业改造项目摩拉维亚布尔诺建筑工作室结构布局可持续的

Arsenic speciation in fish from Greek coastal areas

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Journal of Environmental Sciences 2017年第6期29卷 300-312页

作者： Ioanna Kalantzi Kyriaki Mylona katerina Sofoulaki Manolis Tsapakis Spiros A.Pergantis Institute of Oceanography Hellenic Centre for Marine Science(HCMR)PO Box 2214Heraklion 71003CreteGreece Environmental Chemical Processes Laboratory Department of ChemistryUniuersity of CreteHeraklion 71003CreteGreece

Arsenic speciation analysis was conducted on fish samples （sardine and anchovy） collected from six areas along the Greek coastline, i.e. Artemisium Straits, Thermaikos Gulf, Amvrakikos Gulf, Strymonian Gulf, Thracian Sea, and Elefsina Gulf. Total arsenic levels ranging from 11.8 to 62.6 mg As/kg dry weight were determined. Arsenobetaine, a non-toxic form of arsenic, was found to be the main arsenic species, present at 8.6 to 58.8 mg As/kg dry weight, accounting for 67--95% of the total arsenic. Also detected in all fish samples was dimethylarsinic acid, although at considerably lower concentrations, ranging from 0.072-3.956 mg As/kg dry weight. Monomethylarsonic acid was detected at low levels in all anchovy samples, and only in sardines from one area. Finally, inorganic arsenic in the form of arsenate was detected only in fish at one area, indicating the possible effect of an environmental parameter on its presence at detectable amounts. Statistical analysis revealed the environmental variables, such as salinity, total organic carbon and nitrogen, ammonium, phosphate, total phosphorus, dissolved oxygen and pressure index, are potentially correlated to As species concentrations. Furthermore, based on factor analysis, the biological parameters, such as fish weight, lipids, protein and ash content, that are correlated to As species concentrations of fish were also identified. The interrelationship of arsenobetaine and dimethylarsinic acid concentrations within each fish species was evaluated.

关键词： Arsenic speciationArsenobetaineDimethylarsinic acidArsenateFishEnvironmental and biologicalparameters