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Diagnostics of laser-induced plasma on carbon-based polymer material using atomic and molecular emission spectra

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Plasma Science and Technology 2023年第4期25卷 175-183页

作者： Jelena PETROVIC Dragan RANkovIC Miroslav KUZMAnovIC Jelena SAVOVIC Vasili KIRIS alena NEVAR Mikhail NEDELKO Nikolai TARASENKO University of Belgrade Institute of Nuclear Sciences VincaMike Petrovica Alasa 12-14Belgrade 11001Serbia University of Belgrade Faculty of Physical ChemistryStudentski trg 12-16Belgrade 11000Serbia Institute of Physics National Academy of Sciences of BelarusNezalezhnasci Ave.68-2Minsk 220072Belarus

Time-integrated optical emission analysis of laser-induced plasma on Teflon is *** was induced under atmospheric pressure air using transversely excited atmospheric CO_(2) laser *** is a C-based polymer that is,among other things,interesting as a substrate for laser-induced breakdown spectroscopy analysis of liquid *** study aimed to determine the optimal experimental conditions for obtaining neutral and ionized C spectral lines and C2 and CN molecular band emission suitable for spectrochemical *** of plasma parameters was done using several spectroscopic *** profiles of appropriate C ionic lines were used to determine electron number *** ratio of the integral intensity of ionic-to-atomic C spectral lines was used to determine the ionization temperature.A spectral emission of C2 Swan and CN violet bands system was used to determine the temperature of the colder,peripheral parts of *** critically analyzed the use of molecular emission bands as a tool for plasma diagnostics and suggested methods for possible improvements.

关键词： spectroscopy of laser-induced plasma laser-induced breakdown spectroscopy transversely excited atmospheric CO_(2)laser plasma diagnostics atomic and molecular emission spectra Teflon

Impact of Natural Oil-Based Recycled Polyols on Properties of Cast Polyurethanes

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Journal of Renewable Materials 2018年第7期6卷 697-706页

作者： Hynek Beneš Aleksandra Paruzel JiříHodan Olga Trhlíková Institute of Macromolecular Chemistry AS CR v.v.i.Heyrovsky Sq.216206 Prague 6Czech Republic

In this study, castor oil, rapeseed oil and medium chain triglycerides of coconut oil, were transesterified bymeans of 2-ethyl-2-hydroxymethyl-1,3-propanediol (trimethylolpropane) and consequently used to convertpolycarbonate waste from end-of-life vehicles into liquid polyols. The prepared recycled polyols, composeduniquely of renewable and recycled components, had a hydroxyl number of ca. 250 mg KOH·g−1. They weresuccessfully applied as 100% replacement of a virgin polyol for preparation of solid crosslinked polyurethanes(PU) by solvent-free casting. The produced rigid cast PU exhibited the main transition temperature rangingfrom 44°C to 53°C, the hardness value from 46 to 61 Shore D and the beneficial low water absorption (0.4-0.5wt.%). The PU network structure was highly influenced by the presence of aromatic structures ofpolycarbonate-units and fatty acid compositions. A suitable selection of natural oil thus enabled to adjustthermo-mechanical properties and promote excellent optical transparency of the produced PU.

关键词： Natural oil cast polyurethane bio-based polycarbonate waste recycling

On Non-normal Arc-Transitive 4-Valent Dihedrants

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Acta Mathematica Sinica,English Series 2010年第8期26卷 1485-1498页

作者： István kovCS Botjan KUZMAN Aleksander MALNI FAMNIT University of Primorska PeF University of Ljubljana IMFM University of Ljubljana

Let X be a connected non-normal 4-valent arc-transitive Cayley graph on a dihedral group Dn such that X is bipartite, with the two bipartition sets being the two orbits of the cyclic subgroup within Dn. It is shown that X is isomorphic either to the lexicographic product Cn[2K1] with n 〉 4 even, or to one of the five sporadic graphs on 10, 14, 26, 28 and 30 vertices, respectively.

关键词： Cayley graph arc transitivity dihedral group

Research of Mechanical and Thermal Properties of Composite Material Based on Gypsum and Straw

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Journal of Renewable Materials 2022年第7期10卷 1859-1873页

作者： Nikola Vavřínová Kateřina Stejskalová JiříTeslík Kateřina Kubenková JiříMajer Faculty of Civil Engineering VSB-Technical University of OstravaOstrava70800Czech Republic

This article is focused on the investigation of the mechanical and thermal properties of composite material that could be used for the production of plaster or *** composite material is made of gypsum and reinforcing natural *** article verifies whether this natural reinforcement can improve the investigated properties compared to conventional plasters and gypsum plasterboards made of pure *** this composite material,high-strength plasterboards could then be produced,which meet the higher demands of users than conventional gypsum *** their production,natural waste materials would be used *** part of the development of new building materials,it is necessary to specify essential characteristics for their later use in civil *** wheat straw and three gypsum classes with strengths G2(2 MPa)—gypsum Class I.,G5(5 MPa)—gypsum Class *** G16(16 MPa)—gypsum Class *** used to create the test *** were made with different ratios of the two ingredients,with the percentages of straw being 0%,2.5%,and 5%for each gypsum *** first part of the article describes how the increasing proportion of straw affects the composite’s mechanical properties(flexural strength and compressive strength).The second part of the article focuses on the change of thermal properties(thermal conductivity and specific heat capacity).The last part of the article mentions the verification of the fire properties(single-flame source fire test and gross heat of combustion)of this composite *** research has shown that the increasing proportion of straw reinforcement caused a deterioration in the flexural strength(up to 56.49%in the *** of gypsum Class II.)and compressive strength(up to 80.27%in the *** of gypsum Class III.)and an improvement in the specific heat capacity and thermal conductivity(up to 31.40%in the ***).This composite material is thus not suitable for the production of high-streng

关键词： Composite material gypsum plasterboard crushed straw flexural strength compressive strength thermal conductivity specific heat capacity ignitability gross heat of combustion

Change of photosensitizer fluorescence at its diffusion in viscous liquid flow

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Journal of Innovative Optical Health Sciences 2016年第2期9卷 25-30页

作者： Valeriya S.Maryakhina Vyacheslav V.Gun'kov Orenburg State University 13 Pobedy st. Orenburg 460018Russia

In this paper,the mathematical model of distribution of the injected compound in biological liquid flow has been *** is considered that biological liquid contains a few phases such as water,peptides and *** injected compound(for example,photosensitizer)can interact with peptides and *** the time,viscosity of the biological liquid depends on pathology present in *** obtained distribution of the compound connects on changes of its fluorescence spectra which are registered during fluorescent diagnostics of *** is obtained that the curves do not have monotonic *** is a sharp curves decline in the first few seconds after *** of curves rises after *** is especially pronounced for wavelength 590 nm and 580 nm(near the"transparency window"of biological tissues).Time of inflection point shifts from 8.4 s to 6.9 s for longer ***,difference between curves is little for di®erent viscosity means of the biological ***,additional pathology present in organism does not impact to the results of in vivo biomedical investigations.

关键词： Fluorescence diffusion biomedical diagnostics photosensitizer viscosity

In situ high-pressure nuclear magnetic resonance crystallography in one and two dimensions

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Matter and Radiation at Extremes 2021年第6期6卷 94-103页

作者： Thomas Meier alena Aslandukova Florian Trybel Dominique Laniel Takayuki Ishii Saiana Khandarkhaeva Natalia Dubrovinskaia Leonid Dubrovinsky Center for High Pressure Science and Technology Advanced Research BeijingChina Bayerisches Geoinstitut University of BayreuthBayreuthGermany Department of Physics Chemistry and Biology(IFM)Linkoping UniversitySE-58183 LinkopingSweden Material Physics and Technology at Extreme Conditions Laboratory of CrystallographyUniversity of BayreuthBayreuthGermany

Recent developments in in situ nuclear magnetic resonance(NMR)spectroscopy under extreme conditions have led to the observation of a wide variety of physical phenomena that are not accessible with standard high-pressure experimental ***,inherent di-or quadrupolar line broadening in diamond anvil cell(DAC)-based NMR experiments often limits detailed investigation of local atomic structures,especially if different phases or local environments ***,we describe our progress in the development of high-resolutionNMRexperiments in DACs using one-and two-dimensional homonuclear decoupling experiments at pressures up to the megabar *** this technique,spectral resolutions of the order of 1 ppm and below have been achieved,enabling high-pressure structural *** examples are presented that demonstrate the wide applicability of this method for extreme conditions research.

关键词： NMR extreme dimensions

Comparison of anti-vascular endothelial growth factors, laser treatments and a combination of the both for treatment of central retinal vein occlusion

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International Journal of Ophthalmology(English edition) 2016年第3期9卷 431-433页

作者： Yoav Y.Pikkel Adi Sharabi-nov Itzchak Beiran Joseph Pikkel Tzameret Medical Track Hebrew University Jerusalem 91120 Israel Research Wing Ziv Medical Center Safed Israel and Tel-Hal Academic College Kiryat Shmona 12208 Israel Department of Ophthalmology Rambam Medical Center Haifa 3525408 Israel The B. Rappaport Faculty of Medicine Israel Institute of Technology Haifa 3525427 Israel Departrnent of Ophthalmology Ziv Medical Center Safed 13100 Israel Bar Ilan University Faculty of Medicine Safed 13101 Israel

AIM：To compare changes in visual acuity and macular edema in patients with central retinal vein occlusion（CRVO）treated with intravitreal injections of bevacizumab,macular grid photocoagulation combined with pan retinal photocoagulation（PRP）,or both（bevacizumab＋grid＋PRP）.· METHODS：Our study is a retrospective cohort clinical study that examined patients that suffered from ischemic CRVO with macular *** inclusion criteria were ischemic CRVO with macula edema and the availability of complete medical records for at least 12 mo after *** were patients with diabetes or any other retinal *** reviewed the medical records of patients treated in one ophthalmology departmentcomparing changes in visual acuity and macular edema in patients treated with intravitreal injections of bevacizumab vs those that were treated with macular grid photocoagulation and PRP or *** main outcome measures were the differences in best corrected visual acuity（BCVA） and in macular thickness,as assessed by optical coherence tomography,between the enrollment and the final follow up visits.· RESULTS：Sixty-five patients met inclusion *** were no statistically significant differences among the three groups in the mean changes in macular thickness as measured by ocular coherence tomography（131.5±41.2,108.6±29.2,and 121.1±121.1,P=0.110）,or in visual acuity（0.128±0.077,0.088±0.057,and 0.095±0.065）,for intravitreal injections,macular grid photocoagulation＋PRP and a combination of the treatments,respectively,P =*** proportions of patients with macular edema after treatment were：26.1%,28.6%,and 14.3%,respectively,P=0.499.· CONCLUSION：Similar benefit was observed for intravitreal injections,laser photocoagulation,or a combined regimen in the treatment of CRVO.A nonstatistically significant trend for reduction in macular edema was observed following combined treatment.

关键词： bevacizumab grid laser photocoagulation macular edema optical coherence tomography retinal veinocclusion

Species traits and shoot-root biomass allocation in 20 dry-grassland species

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Journal of Plant Ecology 2018年第2期11卷 273-285页

作者： Iveta Husáková Jacob Weiner Zuzana Münzbergová Department of Botany Faculty of ScienceCharles UniversityBenátská2CZ-12801 PragueCzech Republic Institute of Botany Academy of Sciences of the Czech RepublicZámek 1CZ-25243 PrůhoniceCzech Republic Department of Plant and Environmental Sciences University of CopenhagenThorvaldsensvej 40DK-1871 FrederiksbergDenmark

Aims A plant has a limited amount of resources at any time and it allo-cates them to different *** spite of the large number of previous studies on allocation patterns within single species,knowledge of general patterns in species allocation is still very *** is because each study was done in different condi-tions using different methodology,making generalization *** investigate intraspecific above-versus below-ground biomass allocation among individuals across a spectrum of dry-grassland plant species at two different developmental stages and ask whether allocation is age-and species specific,and whether differences among species can be explained by their life-history traits and *** We collected data on above-and below-ground biomass of seedlings and adult plants of 20 species from a common garden *** analysed data on shoot-root biomass allocation allometrically and studied the relationship between the allometric exponents(slopes on log-log scale),species life-history traits and phylogenetic *** Findings We found isometric as well as allometric patterns of biomass alloca-tion in the studied *** and adult individuals of more than half of the species differed in their above-versus below-ground biomass allometric *** and adult individuals of the remaining species differed in their allometric coefficients(inter-cepts).Annual species generally allocated proportionally more to above-than below-ground biomass as seedlings than as adults,whereas perennial species showed the opposite *** life-history traits,such as plant life span,age of first flowering,month in which the species begin flowering and specific leaf area were much more important in explaining differences in shoot-root allometry among species than were phylogenetic *** suggests that allocation patterns vary greatly among closely related species but can be predicted based on species life-hi

关键词： above-ground biomass below-ground biomass allometry isometry seedling adult plant life-history traits phylogenetic relatedness root-shoot ratio

Determination of dithiocarbamate fungicide using copper solid amalgam electrode

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Determination of dithiocarbamate fungicide using copper soli...