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Chinese Chemical Letters 2015年第6期26卷 779-784页

作者： Gholamhossein Grivani Abbase Ghavami vclav Eigner Michal Duek Aliakbar Dehno khalaji School of Chemistry Damghan University Department of Solid State Chemistry Institute of Chemical TechnologyTechnick Institute of Physics ASCR Department of Chemistry Faculty of ScienceGolestan University

After synthesis of an asymmetric tetradentate ONN＇O＇ Schiff base ligand （H2L） followed by reaction of the synthesized H2L with an equimolar mixture of methanolic solutions of the vO（acac）2, a new oxidovanadium（Iv） Schiff base complex （vOL） was synthesized. The Schiff base ligand and its complex were characterized by FT-IR and Uv-vis spectra and C, H, N analysis, The crystal structure of vOL was also determined by single crystal X-ray analysis. The vOL complex crystallizes in monoclinic space group Cc. The Schiffbase ligand acts as a tetradentate ligand through its two＇iminic nitrogens and two phenolic and acetylacetonate oxygens. Thermogravimetric analysis of the vOL showed that it decomposes in two steps and converts to mixed vanadium oxides at 477℃. In addition, thermal decomposition of the vOL complex in air at 660 ℃ leads to formation of v2O5 nanoparticles with the average size estimated from XRD 49 nm. The catalytic activity of the vOL complex was investigated in the epoxidation reaction and different reaction parameters were optimized. The results showed that the cyclic alkenes were efficiently converted to the corresponding epoxides, whereas the vOL did not appreciably convert the linear alkenes.

关键词： Oxidovanadium(Iv) Scbiff base Crystal structure Nanopartide Epoxidation

To an Axiomatic Model of Rate of Growth

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Applied Mathematics 2013年第9期4卷 1326-1332页

作者： václav Studeny Ivan Mezník Department of Applied Mathematics Faculty of Economics and Administration Masaryk University Brno Czech Republic Institute of Informatics Faculty of Business and Management Brno University of Technology Brno Czech Republic

In the paper an axiomatic approach to express rates of growth is presented. The formula is given of rate of growth at a point as the limit case of rate of growth on an interval and the inverse formula is derived to compute present and future value of capital for an integrable rate of growth. Incidentally some inconsistencies in currently used formulas are pointed out.

关键词： Interest Rate Inflation Rate Rate of Growth

Comparative LIDT measurements of optical components for high-energy HiLASE lasers

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High Power Laser Science and Engineering 2016年第1期4卷 75-83页

作者： Jan vanda Jan evcík Egidijus Pupka Mindaugas ciuka Andrius Melninkaitis Martin Divoky venkatesan Jambunathan Stefano Bonora václav koda Antonio Lucianetti Danijela Rostohar Tomas Mocek valdas Sirutkaitis Hilase Institute of Physics AS CR LIDARIS Ltd. Laser Research Center Vilnius University LUXOR Laboratory CNR IFN Crytur Ltd.

Further advancement of high-energy pulsed lasers requires a parallel development of appropriate optical *** different optical components, such as mirrors and antireflection-coated windows, which are essential for the design of Hi LASE high average power lasers were tested. The following paper summarizes results on the measurements of laser-induced damage threshold of such components, and clearly shows their capabilities and limitations for such a demanding application.

关键词： diode-pumped solid-state laser and applications laser-induced damage

A Part as an Object of Assembly

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World Journal of Engineering and Technology 2021年第4期9卷 904-915页

作者： Štefan václav Peter Pokorný Adriana kamenszká Institute of Production Technologies Faculty of Materials Science and Technology in Trnava Slovak University of Technology Slovakia

Assembly is currently a very important element in the production process. We can also define it as the last stage in the production process. It greatly affects the quality of the product and especially the time needed to make the final product. The presented article is a contribution to the improvement of methods in the field of technological design of the product in terms of assembly, resp. in the field of methodologies known as DFA, which in its entirety means Design of Assembly. The general objective of improving the assembly process is in most cases reducing the cost of the product. With the gradual development of the technologies coming into practice, companies are focusing mainly on improving the elements of assembled products of the assembly system. This state can be achieved, for example, by reducing the number of components, so the complexity and laboriousness of the assembly will be radically reduced. This in turn leads to a decrease in unit assembly costs. Proper assembly settings can help a company succeed in the competition and thus contribute to a stable position of the company in the market. The aim of the article is to find the other objective indicators of assembly quality evaluation.

关键词： Design for Assembly Material Properties Theory of Orientation

不同作物上有害生物类群的物种多样性是否与其科研投入相称

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中国植保导刊 2016年第2期36卷 81-83,80页

作者： václav STEJSkAL Alois HONEk 赵守歧全国农业技术推广服务中心北京100125

在自然科学领域,对不同学科的研究强度不一样,也是有据可查的。但在作物保护、杂草和植物病理等方面,不同学科研究强度的相关数据较少。因此,假设在捷克共和国,有记载不同有害生物类群数量及其经济重要性与在作物保护、杂草和植物病理... 详细信息

在自然科学领域,对不同学科的研究强度不一样,也是有据可查的。但在作物保护、杂草和植物病理等方面,不同学科研究强度的相关数据较少。因此,假设在捷克共和国,有记载不同有害生物类群数量及其经济重要性与在作物保护、杂草和植物病理领域从事该类群研究的科研人员数量呈正相关。基于上述假设研究发现,在人力分配和害虫物种数量之间并不平衡,科学家数量与特定类群的平均经济重要性之间呈现出弱的负相关。

关键词：科学计量学有害生物病原杂草分类学物种多样性科研人员数量

Design of Polymorphic Operators for Efficient Synthesis of Multifunctional Circuits

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Journal of Computer and Communications 2016年第15期4卷 151-159页

作者： Radek Tesař václav Šimek Richard Růžička Adam Crha Faculty of Information Technology Brno University of Technology Brno Czech Republic

Systematic effort dedicated to the exploration of feasible ways how to permanently come up with even more space-efficient implementation of digital circuits based on conventional CMOS technology node may soon reach the ultimate point, which is mostly given by the constraints associated with physical scaling of fundamental electronic components. One of the possible ways of how to mitigate this problem can be recognized in deployment of multifunctional circuit elements. In addition, the polymorphic electronics paradigm, with its considerable independence on a parti- cular technology, opens a way how to fulfil this objective through the adoption of emerging semiconductor materials and advanced synthesis methods. In this paper, main attention is focused on the introduction of polymorphic operators (i.e. digital logic gates) that would allow to further increase the efficiency of multifunctional circuit synthesis techniques. key aspect depicting the novelty of the proposed approach is primarily based on the intrinsic exploitation of components with ambi- polar conduction property. Finally, relevant models of the polymorphic operators are presented in conjunction with the experimental results.

关键词： Digital Circuits Reconfiguration Multifunctional Logic Ambipolarity Polymorphic Electronics Synthesis Methods

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墓葬壁画胶结材料的探讨分析

考古与文物 2021年第5期 123-128页

作者：马珍珍严静赵西晨 václav Pitthard 黄晓娟陕西省考古研究院考古发掘现场文物保护国家文物局重点科研基地维也纳艺术史博物馆

胶结材料不仅对稳定墓葬壁画结构、形成颜色起着关键作用,而且是壁画制作材料、工艺研究的重要组成部分。因其成分复杂、降解明显、含量极低,一直是国内外壁画分析保护的热点和难点。本文以我国几处不同时代、地域的典型墓葬壁画作为研... 详细信息

胶结材料不仅对稳定墓葬壁画结构、形成颜色起着关键作用,而且是壁画制作材料、工艺研究的重要组成部分。因其成分复杂、降解明显、含量极低,一直是国内外壁画分析保护的热点和难点。本文以我国几处不同时代、地域的典型墓葬壁画作为研究对象,运用成熟的GC-MS分析技术发现杨桥畔东汉墓、韩休唐墓壁画的颜料层均采用了桐油作胶结材料,湖南明墓壁画地仗层不仅添加有桐油,还存在有淀粉。基于上述实验结果,探讨了桐油、淀粉作为墓葬壁画胶结物的科学合理性。本研究丰富、扩宽了研究者对我国墓葬壁画胶结材料的认知,为壁画制作工艺、劣化机理、保护修复材料选择等研究奠定了科学基础。

关键词：墓葬壁画胶结材料 GC-MS

Silver flr tree-ring fluctuations decrease from north to south latitude—total solar irradiance and NAO are indicated as the main influencing factors

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Forest Ecosystems 2023年第6期 717-731页

作者： václav ?im?nek Anna Prok?pková Zdeněk vacek Stanislav vacek Jan Cukor Jirí Reme? vojtěch Hájek Giuseppe D'Andrea Martin ?álek Paola Nola Osvaldo Pericolo ?árka Holzbachová Francesco Ripullone Faculty of Forestry and Wood Sciences Czech University of Life Sciences Prague Forestry and Game Management Research Institute 3. Czech Academy of Sciences Institute of Vertebrate Biology Faculty of Environmental Sciences Czech University of Life Sciences Prague Department of Earth and Environmental Sciences University of Pavia Forests of the Czech Republic SOE School of Agricultural Forestry and Environmental Sciences University of Basilicata

Silver flr(Abies alba Mill.) is a flexible European tree species, mainly vegetating within the mountainous regions of Europe, but its growth responses across its latitudinal and longitudinal range have not yet been satisfactorily verifled under changing environmental conditions. This study describes the tree-ring increment of silver flr in research plots across a latitudinal gradient from the northern range in Czechia(CZ), through Croatia(HR) to the southernmost range in Italy(IT). The research aims to analyze in detail the dynamics and cyclicity of the ringwidth index(RWI) and how it relates to climatic factors(temperature and precipitation), the North Atlantic Oscillation(NAO), and total solar irradiance(TSI), including the determination of latitude. The results show that the main drivers affecting flr growth are the seasonal NAO index and TSI. Monthly temperatures affect RWI early in the vegetation season, while lack of precipitation during the summer is a limiting factor for flr growth,especially in July. Seasonal temperatures and temperatures in June and July negatively impact, while seasonal precipitation totals in the same months positively influence the RWI in all research plots across meridian. The longest growth cycles in flr RWI were recorded in the northernmost studied plots in CZ. These cyclical fluctuations recede approaching the south. The cyclic increase in RWI is related to the TSI, which decreases its effect from north to south. The TSI?s effects vary, positively impacting CZ but negatively influencing HR while remaining relatively neutral in IT. On the other hand, seasonal NAO tends to negatively affect silver flr growth in HR and CZ but has a mildly positive effect in IT. In conclusion, the TSI and the influence of the seasonal NAO index are prevalent in the flr RWI and are accompanied by a greater cyclicity of RWI in Central Europe(temperature optimum) than in the Italian Mediterranean region, where this tree species is limited by climatic condi

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悲哀永远不要同他们的名字连在一起

青年视觉 2018年第2期 148-157页

作者：李怡 václav Jirásek(photo) 不详

自从人类堕落以来,就把劳动视为一种苦修,指望它具有赎罪的力量。而工业文明则追逐生产效率,与之呼应的是商业规则所指向的人性的自私自利。道德的沦丧和工业的碾压令精神和自然的场域均备受考验。

关键词：商业规则自私自利赎罪

Diporphyrin tweezer for multichannel spectroscopic analysis of enantiomeric excess

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Frontiers of Chemical Science and Engineering 2020年第1期14卷 28-40页

作者： Daniel T.Payne Mandeep kChahal vaclav Brezina Whitney A.Webre katsuhiko Ariga Francis D’Souza Jan Labuta Jonathan P.Hill WPI Center for Materials Nanoarchitectonics National Institute for Materials ScienceIbaraki 305-0044Japan Department of Macromolecular Physics Faculty of Mathematics and PhysicsCharles University18000 PragueCzech Republic Department of Chemistry University of North TexasDentonTX 76203USA Department of Advanced Materials Science Graduate School of Frontier SciencesThe University of TokyoChiba 277-8561Japan

Chiral 1,1’-binaphthyl-linked diporphyrin‘tweezers’(R)-1/(S)-1 and the corresponding zinc(II)complexes(R)-2/(S)-2 were prepared as chiral host molecules,and their utility for chiral analyses(especially enantiomeric excess(ee)determinations)were ***(1-n-dodecyl)porphyrins were used for the first time as the interacting *** capabilities of the diporphyrin tweezers were investigated by titrations with(R,R)-and(S,S)-cyclohexane-1,2-diamine(CHDA).The host molecules could be used as multichannel probes of ee by using Uvvis,circular dichroism(CD),fluorescence emission and 1H nuclear magnetic resonance(1 H-NMR)*** configurations could also be differentiated using CD or 1HNMR *** three optical techniques give good resolution of ee with reasonable sensitivity considering the low concentrations used(ca.10^-6 mol·L^-1).The ee determination of CHDA enantiomers using NMR spectroscopy is also possible because of the reasonably well separated resonances in the case of(R,R)-and(S,S)-***-metallated(R)-1/(S)-1 hosts could not be used to detect chiral information in a strongly acidic chiral *** work demonstrates the utility of 1,1’-binapthyllinked chiral hosts for chiral analysis of ditopically interacting enantiomers.

关键词： porphyrin dimer chirality enantiomeric excess CD fluorescence