325 research outputs found

    Влияние состава водной бронировки заряда из сплава тротила с гексогеном на выход и качество детонационного наноалмаза и алмазной шихты при детонационном синтезе

    No full text
    Приведены факторы детонационного синтеза, определяющие выход детонационных наноалмазов, алмазной шихты и их качество. Описано влияние такого важного фактора, как состав бронировки (оболочки) заряда взрывчатого вещества. Рассмотрены три различных варианта подрыва заряда взрывчатого вещества – газовый, водный, ледяной, их преимущества и недостатки. Показано влияние состава смесей водных растворов различных веществ (органических и неорганических) на результат детонационного синтеза.Наведено фактори детонаційного синтезу, що визначають вихід детонаційних наноалмазів, алмазної шихти та їх якість. Описано вплив такого важливого чинника, як склад бронювання (оболонки) заряду вибухової речовини. Розглянуто три різні варіанти підриву заряду вибухової речовини – газовий, водний, крижаний, їх переваги і недоліки. Показано вплив складу сумішей водних розчинів різних речовин (органічних і неорганічних) на результат детонаційного синтезу.This paper presents the factors of detonation synthesis, determining detonation nanodiamonds and the diamond blend yield and their quality We describe the effect of such an important factor as the composition of armor protection (shell) of the explosive charge. We consider three different ways of undermining an explosive charge – gas, water, ice, their advantages and disadvantages. We also shows the influence of the aqueous solutions composition of various mixtures of substances (organic and inorganic) on detonation synthesis result in details

    Влияние состава бронировки стандартного заряда тротил–гексоген (50/50) на содержание примесей в детонационных наноалмазах

    No full text
    Рассмотрена возможность влияния на выход детонационных наноалмазов (ДНА), алмазосодержащей шихты (АШ), содержание и состав несгораемых примесей в АШ и ДНА изменения состава водной бронировки классического заряда тротил-гексоген (50/50). В качестве соединений, влияющих на указанные параметры, использовали гидразин, уротропин, аммиак, мочевину, Трилон Б, аминотетразол и борную кислоту. Оптимальным по комплексу параметров оказался уротропин; в результате получен максимальный выход ДНА (6,9%) и АШ (13,4%); близкий выход АШ и ДНА получен при использовании в бронировке гидразина и мочевины. При использовании в бронировке борной кислоты существенно сократилась номенклатура элементов примесей в АШ и ДНА при приемлемом выходе АШ (11,1%) и ДНА (6,13%).Розглянуто можливість впливу на вихід детонаційних наноалмазів (ДНА), алмазовмістної шихти (АШ), вміст і склад неспалених домішок в АШ і ДНА зміни складу водного бронювання класичного заряду тротил-гексоген (50/50). В якості з'єднань, що впливають на зазначені параметри, використовували гідразин, уротропін, аміак, сечовину, Трилон Б, амінотетразол і борну кислоту. Оптимальним за комплексом параметрів виявився уротропін; в результаті отримано максимальний вихід ДНА (6,9%) і АШ (13,4%); близький вихід АШ і ДНА отриманий при використанні в бронюванні гідразину і сечовини. При використанні в бронюванні борної кислоти істотно скоротилася номенклатура елементів домішок в АШ і ДНА при прийнятному виході АШ (11,1%) і ДНА (6,13%).The paper considers the possibility to influence the yield of detonation nanodiamonds (DND), diamond blend (DB), the content and composition of incombustible impurities in DB and DND by changing the aqueous armoring composition of the classical charge TNT-RDX (50/50 As the compounds influencing the above parameters were used: hydrazine, urotropin, ammonia, urea, Trilon B, aminotetrazole and boric acid. Optimal for the complex of parameters was the use of urotropine, the maximum yield of DND (6.9%) and DB (13.4%) was obtained, a close yield of DB and DND was obtained when hydrazine and urea were used in the armoring. The use of boric acid in armor protection can significantly reduce the nomenclature of impurity elements in the DB and DND with an acceptable yield of DB (11.1%) and DND (6.13%). Using clean water for booking is not effective

    Data driven Xpath generation

    Get PDF
    The XPath query language offers a standard for information extraction from HTML documents. Therefore, the DOM tree represen- tation is typically used, which models the hierarchical structure of the document. One of the key aspects of HTML is the separation of data and the structure that is used to represent it. A consequence thereof is that data extraction algorithms usually fail to identify data if the structure of a document is changed. In this paper, it is investigated how a set of tab- ular oriented XPath queries can be adapted in such a way it deals with modifications in the DOM tree of an HTML document. The basic idea is hereby that if data has already been extracted in the past, it could be used to reconstruct XPath queries that retrieve the data from a different DOM tree. Experimental results show the accuracy of our method

    Exploring effects of remote ischemic preconditioning in a pig model of hypothermic circulatory arrest

    Get PDF
    Objectives. During aortic and cardiac surgery, risks for mortality and morbidity are inevitable. Surgical setups involving deep hypothermic circulatory arrest (DHCA) are effective to achieve organ protection against ischemic injury. The aim of this study was to identify humoural factors mediating additive protective effects of remote ischemic preconditioning (RIPC) in a porcine model of DHCA. Design. Twenty-two pigs were randomized into the RIPC group (n=11) and the control group (n=11). The RIPC group underwent four 5-minute hind limb ischemia-reperfusion cycles prior to cardiopulmonary bypass and DHCA. All animals underwent identical surgical procedures including 60min DHCA at 18 degrees C. Blood samples were collected from vena cava and sagittal sinus at several time points. After the 8-hour follow-up period, the brain, heart, and kidney tissue samples were collected for tissue analyses. Results. Serum levels of brain damage marker S100B recovered faster in the RIPC group, after 4hours of the arrest, (pPeer reviewe

    How predation and landscape fragmentation affect vole population dynamics

    Get PDF
    Background: Microtine species in Fennoscandia display a distinct north-south gradient from regular cycles to stable populations. The gradient has often been attributed to changes in the interactions between microtines and their predators. Although the spatial structure of the environment is known to influence predator-prey dynamics of a wide range of species, it has scarcely been considered in relation to the Fennoscandian gradient. Furthermore, the length of microtine breeding season also displays a north-south gradient. However, little consideration has been given to its role in shaping or generating population cycles. Because these factors covary along the gradient it is difficult to distinguish their effects experimentally in the field. The distinction is here attempted using realistic agent-based modelling. Methodology/Principal Findings: By using a spatially explicit computer simulation model based on behavioural and ecological data from the field vole (Microtus agrestis), we generated a number of repeated time series of vole densities whose mean population size and amplitude were measured. Subsequently, these time series were subjected to statistical autoregressive modelling, to investigate the effects on vole population dynamics of making predators more specialised, of altering the breeding season, and increasing the level of habitat fragmentation. We found that fragmentation as well as the presence of specialist predators are necessary for the occurrence of population cycles. Habitat fragmentation and predator assembly jointly determined cycle length and amplitude. Length of vole breeding season had little impact on the oscillations. Significance: There is good agreement between our results and the experimental work from Fennoscandia, but our results allow distinction of causation that is hard to unravel in field experiments. We hope our results will help understand the reasons for cycle gradients observed in other areas. Our results clearly demonstrate the importance of landscape fragmentation for population cycling and we recommend that the degree of fragmentation be more fully considered in future analyses of vole dynamics

    Measurement of the inclusive and differential t(t)over-bar gamma cross sections in the single-lepton channel and EFT interpretation at root s=13 TeV

    Get PDF
    Peer reviewe

    Measurement of the Higgs boson width and evidence of its off-shell contributions to ZZ production

    Get PDF
    Since the discovery of the Higgs boson in 2012, detailed studies of its properties have been ongoing. Besides its mass, its width—related to its lifetime—is an important parameter. One way to determine this quantity is to measure its off-shell production, where the Higgs boson mass is far away from its nominal value, and relating it to its on-shell production, where the mass is close to the nominal value. Here we report evidence for such off-shell contributions to the production cross-section of two Z bosons with data from the CMS experiment at the CERN Large Hadron Collider. We constrain the total rate of the off-shell Higgs boson contribution beyond the Z boson pair production threshold, relative to its standard model expectation, to the interval [0.0061, 2.0] at the 95% confidence level. The scenario with no off-shell contribution is excluded at a p-value of 0.0003 (3.6 standard deviations). We measure the width of the Higgs boson as Γ\GammaH_H=3.21.7+2.4^{+2.4}_{−1.7}MeV, in agreement with the standard model expectation of 4.1 MeV. In addition, we set constraints on anomalous Higgs boson couplings to W and Z boson pairs
    corecore