bluuebunny/crossref_metadata_2025 huggingface dataset:
Multidisciplinary challenge in the design of a MWCNTs-based polymer smart structure
Authors: Arena Maurizio , Viscardi Massimo , Guadagno Liberata , Vertuccio Luigi , Barra Giuseppina
Published: November 2018

Smart structures represent of course a current challenge for the application on the aircrafts. Dealing for example with morphing and variable-shape structures, the skin needs to face extremely high strains, while withstanding the operational loads in order to ensure a smooth profile to the complete system. In this context, the authors led the design and manufacturing of carbon fiber-reinforced composite panels, including different filler infusions based on multi-walled carbon nanotubes (MWCNTs) technology. The vibro-acoustic tests have been carried out on an innovative formulation for the characterization of the damping properties related to such micro-handling treatments. The percentage of nano-filler has been chosen so as to be close to the percolation threshold of the material (about 5wt%). As a result of synergic collaboration between Smart Structures Lab of University of Naples “Federico II” and University of Salerno within H2020-MASTRO (Intelligent bulk MAterials for Smart TRanspOrt industries) research project, a multi-functional composite concept has been idealized and developed. The main purpose is to develop intelligent bulk materials for the transport field based on the novel concepts like self-sensing, self-deicing, self-curing, self-healing and selfprotection methodologies to enhance consumer safety, component life-span and performance while reducing maintenance and manufacturing costs. The functionality of the developed components will be demonstrated under relevant conditions at prototype level with special attention to the aerospace structures.
Numerical simulation and performances evaluation of the pulse detonation engine
Authors: Prisacariu Vasile , Rotaru Constantin , Cîrciu Ionică , Niculescu Mihai
Published: November 2018

A pulse detonation engine (PDE) is a type of propulsion system that uses detonation waves to combust the fuel and oxidizer mixture. The engine is pulsed because the mixture must be renewed in the combustor between each detonation wave. Theoretically, a PDE can operate from subsonic up to hypersonic flight speed. Pulsed detonation engines offer many advantages over conventional propulsion systems and are regarded as potential replacements for air breathing and rocket propulsion systems, for platforms ranging from subsonic unmanned vehicles, long range transports, high-speed vehicles, space launchers to space vehicles. The article highlights elements of the current state of the art, but also theoretical and numerical aspects of these types of unconventional engines. This paper presents a numerical simulation of a PDE at h=10000 m with methane as working fluid for stoichiometric combustion, in order to find out the detonation conditions.
Identification of BDS Registers
Authors: Topková Tereza , Pleninger Stanislav
Published: November 2018

The SSR Mode S technology is currently one of the major means of surveillance in ATM. Addressed surveillance enables the elicitation of replies from Mode S transponder on board of an aircraft containing different flight information in the so-called BDS registers. The type of BDS register as well as its content is characterised by a number of the BDS registers which is determined according to SSR interrogation by default. The study deals with the development of a heuristic algorithm for identification of a particular BDS register with the assumption that the radar query is unknown. A BDS number is assigned to the appropriate message on the basis of the unique bit sequences and other criteria. The algorithm provides the opportunity to obtain various flight data from the aircraft by only receiving addressed surveillance replies on 1090 MHz frequency.
Optimal designs of electric vehicles for long-range mobility
Authors: Dimitrova Zlatina
Published: November 2018

This paper introduces the major priorities of the automotive industry of reducing energy consumption and emissions of the passenger cars of the future and of delivering an efficient mobility service for customers. The number of electric vehicles and hybrid electric vehicles is increasing in the mobility market. The problems of the range and the energy storage of the vehicle on board are important. This paper studies the energy system of electric vehicles for different ranges and mobility usages. A multi-objective optimization method is applied to estimate the optimal vehicle energy system designs for urban mobility and for long way electric mobility (> 500 km). Optimal designs considering technical, economic and environmental criteria are presented. The relations between the vehicle ranges and the energy densities of high voltage batteries are illustrated. The boundary of the system is extended to the vehicles and the grid system, including the charging infrastructure. The vehicle energy systems and recharging needs are analysed for a range of 500 km on electric drive.
Life cycle assessment of electric and conventional cars energy consumption and CO2 emissions
Authors: Evtimov Ivan , Ivanov Rosen , Kadikyanov Georgi , Staneva Gergana
Published: November 2018

This paper presents an analysis concerning the effectiveness of electric traction in comparison with conventional cars. The Life Cycle Assessment method is used. It estimates the energy spent for the extraction of the raw materials/sources, manufacturing and transportation of the components and the vehicle, motion, maintenance and repair during exploitation period and the recycling process. The impact of the production technology of the electric energy, needed for charging the battery, is taken into account. The energy consumption and CO2 emissions for the life cycle of electric and conventional cars are presented on graphs. Examples for Bulgaria and EU countries are given. The exploitation conditions in which the electric car is more effective regarding CO2 equivalent emissions are shown. The main influence on the effectiveness of electric cars has the structure of the energy mix of the country where the electric car is produced and is used in exploitation.
HCCI combustion control using advanced gasoline direct injection techniques
Authors: Hunicz Jacek , Mikulski Maciej , Komsta Henryk
Published: November 2018

Homogeneous Charge Compression Ignition (HCCI) is a promising low temperature combustion technology for reciprocating engines that offers high fuel efficiency and extremely low exhaust emissions. However, combustion control should be improved and operating range should be widened for the technology to achieve production level. In this study an overview of different direct gasoline injection control approaches, applied to improve stability at low engine loads and to reduce pressure rise rates at high load regime, is presented. The tests are performed on a single-cylinder research engine operated in a negative valve overlap (NVO) mode for residual gasses trapping. The investigated direct injection schemes included: (i) fuel injection during the NVO period to improve mixture reactivity and take an advantage of exhaust-fuel reactions thermal effects, (ii) fuel injection during intake stroke to create homogeneous charge and (iii) late fuel injection during compression stroke to create stratified charge. The results showed that application of early NVO injection enables active control of combustion timing at nearly idle conditions. The late fuel injection, during the compression stroke, enabled mitigation of excessive pressure rise rates at high engine load regime.
A Fuzzy Group Decision Making for a Rail-Road Transshipment Yard Micro Locaton Problem
Authors: Belošević Ivan , Milinković Sanjin , Marton Peter , Vesković Slavko , Ivić Miloš
Published: November 2018

Rail-road transhipment yards serve as interchange points between rail and road providing transhipment of loading units. These yards are of great importance for smooth functioning not only of railways but also of the whole intermodal transportation chains. The problem of choosing location of railway facilities, such as yards and depots, has great practical importance and is widely considered in the literature. In this paper, we present a multi criteria decision making (MCMD) model for selecting the most suitable micro location of a rail-road transhipment yard. The developed MCMD model is based on combining a compromise programming technique with the theory of fuzzy numbers. This approach was chosen to solve the considered location problem due to the specific decision-making environment that reflects in the presence of non-commensurable and conflicting criteria. As a case study we analysed several alternatives for locating rail-road transhipment facilities in the area of the rail freight yard in Vršac. The results confirm validity and usefulness of this approach.
Practical application of city logistics in the city of Trenčín
Authors: Dedík Milan , Čechovič Tomáš , Gašparík Jozef
Published: November 2018

At present, mobility is an important part of everyday activities in cities. The increasing number of passenger and freight vehicles on the widening transport infrastructure raises several problems. The range of use of public passenger transport does satisfy enough the citizens needs and its use is constantly decreasing, especially in the new EU countries. One of the reasons is also the growing sale and production of new passenger cars in the EU, resulting in congestion in the road infrastructure of cities. These issues are dealt with the modern City Logistics concept. The paper is aimed to the basic principles of city logistics, the reasons for its development and, in particular, the possibilities of practical use. An example is the city of Trenčín in Slovakia, where a regional rail passenger transport is proposed for city traffic service including Park and Ride system.
Computer simulation of railway wagon brake disc casting
Authors: Futáš Peter , Pribulová Alena , Fedorko Gabriel , Molnár Vieroslav , Mikušová Nikoleta
Published: November 2018

CAD systems serving as the model for real industrial processes are almost an inseparable part of manufacturing in many industry branches. The use of simulation programs in the foundry industry is perceived as a tool for the visualization of the processes involved in the production of castings. They are also used to resolve possible issues and imperfections before the production begins. Consequently, it enhances the quality and reduces product-manufacturing-related financial costs. The paper tackles the issue of how to resolve the occurrence of defects – shrinkages in the railway wagon disc casting while using a simulation program. The 3D model of the casting and of the system of gates was constructed in the CATIA CAD system. The mere simulation of the casting and solidification process was done in the NovaFlow&Solid program. After evaluating the results of the simulation, the correction of the casting and gates was made in order at once to enhance the quality of the casting and reduce the production costs in the manufacturing of this casting. In the production of the brake disk casting, the main issues are little usage of molten metal during casting and the considerable occurrence of shrinkages, which causes the increased economic costs of its production.
Simulation options for the airport terminal People Mover AGV system with ExtendSim 8
Authors: Fedorko Gabriel , Molnár Vieroslav , Ščavnický Patrik
Published: November 2018

The use of AGV vehicles is expanding to an ever-wider range of diverse areas. In addition to securing effective logistics processes in the industry, AGV systems have been deployed in quite non-traditional areas, for example in health or transportation of persons. Although AGV systems intended for passenger transport do not belong to AGV systems according to the definition of VGA standards, they can still be regarded as a regular member of this category of vehicles. In order to ensure their reliable operation, the same tools as for conventional AGV systems can be used. Such tools include a computer simulation method. The paper presents the model of People Mover AGV in order to analyse passenger transport between airport terminals.
The specificity of crossing air borders by civil and state aircraft
Authors: Helnarska Karolina Julia , Krawczyk Jacek , Korytek Łukasz
Published: November 2018

The article presents issues related to the legal regulations regarding the crossing of airspace boundaries by civil and state aircraft. Additionally, there are also described differences in the formal requirements for the conduct of civil and state aircraft operations. In addition, there have been described difficulties in the implementation of tasks for state aviation, which may have a negative impact on the protection of military contingents abroad, outflows outside the country, security of visits by state representatives and international cooperation. The process of acquiring permission to cross the air border by a state aircraft is also presented, which is much more complicated than the requirements for civil aircraft, the limitations of which are related only to the weight of the aircraft, the purpose of the flight and the technical and operational capabilities of the machine. The following article will bring the process of obtaining diplomatic approvals for state aircraft flights. The rules and formal as well as legal principles that must be met to obtain diplomatic approval for the conduct of an aircraft operation by a state aircraft will be described.
Geographic structure and regional socio-economic impact of low-cost airlines in selected cities of Central and Eastern Europe: the role model for Belarus.
Authors: Bezruchonak Andrei
Published: November 2018

The goal of this article is to analyse the structure of geographic presence and the socio-economic impact of low-cost carriers (LCCs) in the selected countries of Central and Eastern Europe (neighbouring the Republic of Belarus – Poland, Lithuania, Latvia, Ukraine and Russia). The model of the current geographic configuration of the LCCs network from the cities and airports with the closest proximity to Belarus was designed. The current market trends show that the major LCCs on the market are Wizz Air and Ryanair, and they are increasing their share at the markets of the countries analysed (particularly after Ryanair entered Ukrainian market in 2018). The overview of socio-economic impact of LCCs is discussed with accent on the possible benefits and outcomes of LCCs entry to the Republic of Belarus.
Regional transportation development for development at fertilizer plants in North Sumatra (case study)
Authors: Siregar Ikhsan , Tambunan Mangara M.
Published: November 2018

Supply chain activity has an opportunity for the occurrence of risk. Therefore, risk management is needed in the handling of risk with the aim to minimize the risk level and impact of those risks. PT. XYZ of PT Pupuk Indonesia (Persero) engaged in the fertilizer industry. The main product produced is urea fertilizer. In the production process, the factory is supported by adequate production facilities and international standard technology. Currently, PT XYZ does not yet have risk management which explicitly discusses the proposed risk management along with the handling strategies required by the company. By looking at the current condition of the company, in order to achieve the goals to be achieved the company needs a good supply chain planning such as by identifying the risks that exist in the supply chain and preventive measures. Performed risk analysis and evaluation of potential supply chain companies using HOR (House Of Risk) tools. After the research there were 42 risk events and 42 risk agents. With the 80/20 pareto approach, 9 risk agents are planned for mitigation action. There are 11 recommended risk mitigation actions recommended to the company in the hope of addressing the risk of urea fertilizer supply chain.
Digitalization of intellectualization of logistics of intermodal and multimodal transport
Authors: Bubnova Galina V. , Efimova Olga V. , Karapetyants Irina V. , Kurenkov Petr V.
Published: November 2018

In this paper, the problem of managing various types of transportation under digitalization conditions is considered. Possible schemes of interaction between the subjects of the transport services market and various modes of transport under foreign trade are presented. It is recommended to take into account all types of interaction and coordination of activities of different modes of transport, as well as transport and other markets, when choosing a route for transport and freight flows.
Zur Frage der klinischen Signifikanz in deutschen rehabilitationswissenschaftlichen Interventionsstudien – eine Bestandsaufnahme der gängigen Praxis
Authors: Höder Jürgen , Hüppe Angelika
Published: November 2018

Ziel Es wird untersucht, ob und wie „klinische Signifikanz“ in deutschen rehabilitationswissenschaftlichen Interventionsstudien behandelt wird.

Methode Analyse von 64 zwischen 2012 und 2016 publizierten Studien, die Daten zu mindestens 2 Messzeitpunkten berichteten und an denen deutsche Wissenschaftler und Rehaeinrichtungen beteiligt waren.

Ergebnisse In 28% der Studien wird klinische Signifikanz erwähnt, 19% definieren, was sie darunter verstehen, 13% begründen die Definition. 70% berichten Maßzahlen, die etwas über klinische Signifikanz aussagen könnten, aber nur 28% nutzen die Zahlen tatsächlich dafür. Die am häufigsten verwendeten Statistiken sind Effektstärkemaße (45%). Sie werden ohne weitere Reflexion schematisch im Sinne der Cohen‘schen Kategorien interpretiert.

Fazit Die klinische Relevanz der Befunde zu bestimmen und zu diskutieren, findet sich in der Mehrzahl der Studien nur in Ansätzen oder gar nicht.
Die bewährte Indikation in der Zahnheilkunde
Authors: Schule Roland
Published: November 2018

Grundsätzlich bestehen der Wunsch und der therapeutische Wille, bei akuten Erkrankungen eine rasche und zielführende Arzneimittelauswahl zu treffen, ohne in jedem einzelnen Krankheitsfall das komplette Programm für die Behandlung von akuten Krankheiten zu bemühen. Was nach der Erfahrung im Umgang mit Epidemien erkannt wurde und in der Ausführung im „Organon“ studiert werden kann, lässt sich auch auf wiederkehrende und akute Beschwerden in der Zahnheilkunde übertragen. Ein großes Patientenklientel mit gleichlautender Diagnose und damit verbunden einer vereinheitlichten Symptomatik erlaubt die Zuordnung zu einer „bewährten Indikation“. Das Spektrum für den Notfallbereich innerhalb der Zahnmedizin deckt Entzündungen, Verletzungen, vielschichtige Schmerzzustände und psychisch-vegetative Belastungen ab. Für den erfahrenen Kliniker bedeutet diese Sonderform der homöopathischen Verordnung eine große Hilfestellung im Praxisalltag. Sie erlaubt rasche Sofortmaßnahmen im Rahmen der Ersten Hilfe und schafft Raum für weitere, tiefgreifende Fallaufnahme und Arzneimittelbestimmung. Alleine für sich betrachtet erfüllt die „bewährte Indikation“ nie das individualisierende Krankheitsverständnis im Rahmen der klassischen Homöopathie. Die therapeutische Kunst besteht in der richtigen Wahl zur richtigen Zeit.
Ein vermuteter Schlangenbiss und die Irrwege der Medikamentenwahl
Authors: Trebin Ernst
Published: November 2018

Die Fallbeschreibung verdeutlicht den manchmal komplizierten Weg der Mittelsuche und die bei der jeweiligen Verdachtsdiagnose indizierten Arzneien bis hin zur Mittelwahl Ledum.
Homarus (gammarus) – zwei Kasuistiken
Authors: Mühlbauer Beatrix
Published: November 2018

Vorgestellt werden 2 Fälle, die durch Gabe des Mittels Homarus gammarus Linderung erfahren.
Cucurbitacin B Induces Hypermethylation of Oncogenes in Breast Cancer Cells
Authors: Dittharot Kanthanadon , Dakeng Sumana , Suebsakwong Parichat , Suksamrarn Apichart , Patmasiriwat Pimpicha , Promkan Moltira
Published: November 2018

Breast cancer is a complex disease driven by multiple factors including both genetic and epigenetic alterations. Recent studies revealed that abnormal gene expression induced by epigenetic changes including aberrant promoter methylation plays a critical role in human breast carcinogenesis. Cucurbitacin B has antiproliferative activity against various human breast cancer cells, but the molecular mechanism is not completely understood. In this study, we explore the influence of cucurbitacin B from Trichosanthes cucumerina on the methylation status at the promoter of oncogenes c-Myc, cyclin D1, and survivin in breast cancer cell lines. Growth inhibitory effect of cucurbitacin B on breast cancer cells was assessed by MTT assay and colony formation assay. Methylation status of genomic DNA was determined by methylation-specific PCR. Gene and protein expression levels of all genes studied were analyzed by real-time RT-PCR and western blot. The results indicated that cucurbitacin B could inhibit cell growth in breast cancer cells. The oncogene promoters are usually hypomethylated in cancer cells. Upon cucurbitacin B treatment, upregulation of DNMT1 and obvious heavy methylation in the promoters of c-Myc, cyclin D1, and survivin, which consequently downregulated the expression of all these oncogenes, were observed. Hence, cucurbitacin B proved to be a potential cancer therapeutic agent, in part by inducing hypermethylation and silences the oncogenic activation.
Selective Semi-Hydrogenation of Terminal Alkynes Promoted by Bimetallic Cu-Pd Nanoparticles
Authors: Radivoy Gabriel , Buxaderas Eduardo , Volpe María
Published: November 2018

The selective semi-hydrogenation of terminal alkynes was efficiently performed, under mild reaction conditions (H2 balloon, 110 °C), promoted by a bimetallic nanocatalyst composed of copper and palladium nanoparticles (5:1 weight ratio) supported on mesostructured silica (MCM-48). The Cu-PdNPS@MCM-48 catalyst, which demonstrated to be highly chemoselective towards the alkyne functionality, is readily prepared from commercial materials and can be recovered and reused after thermal treatment followed by reduction under H2 atmosphere.
Synthesis of 1,4-Disubstituted 1H-1,2,3-Triazoles from 4-(1-Adamantyl)benzyl Azide through a 1,3-Dipolar Cycloaddition Reaction
Authors: Tebbani Dahmane , Silva Artur , Hocine Oussama
Published: November 2018

A series of new 1,4-disubstituted 1H-1,2,3-triazole derivatives were synthesized by an efficient copper-catalyzed 1,3-dipolar cyclo­addition reaction of 4-(1-adamantyl)benzyl azide with several terminal alkynes. The copper catalyst was used to provide 1,4-disubstituted 1,2,3-triazoles regioselectively in good yields.
In Vivo Biocompatibility of a Novel Expanded Polytetrafluoroethylene Suture for Annuloplasty
Authors: Dudenhöffer Daniel W. , Laschke Matthias W. , Giebels Christian , Karliova Irem , Schneider Ulrich , Menger Michael D. , Schäfers Hans-Joachim
Published: November 2018

Background Expanded polytetrafluoroethylene (ePTFE) is a suture material for annuloplasty in aortic valve repair. For this particular application, it should induce minimal local stress and promote rapid tissue incorporation. To achieve this, a novel ePTFE suture with a larger diameter and high porosity in its midsection has been developed. Herein, we analyzed the acute and chronic tissue reaction to this suture material compared with a commercially available control ePTFE suture.

Methods Novel and control suture samples were implanted into dorsal skinfold chambers of BALB/c mice to analyze the early inflammatory response using intravital fluorescence microscopy over 14 days. Additional suture samples were implanted for 4 and 12 weeks in the flank musculature of mice and analyzed by histology and immunohistochemistry.

Results The implantation of novel and control ePTFE suture into the dorsal skinfold chamber did not induce an acute inflammation, as indicated by physiological numbers of rolling and adherent leukocytes in all analyzed venules. Chronic implantation into the flank musculature showed a better tissue incorporation of the novel ePTFE suture with more infiltrating cells and a higher content of Sirius red+ collagen fibers when compared with controls. Cell proliferation and viability as well as numbers of recruited CD68+ macrophages, myeloperoxidase+ neutrophilic granulocytes and CD3+ lymphocytes did not significantly differ between the groups.

Conclusion The novel ePTFE suture exhibits a good in vivo biocompatibility which is comparable to that of the control suture. Due to its improved tissue incorporation, it may provide a better long-term stability during annuloplasty.
Implementation of a Standardized Patient Safety Checklist in Ophthalmic Surgery
Authors: Boese Erin , Lee Paul , Greenberg Grant , Harrison Richard , Weizer Jennifer
Published: November 2018

Objective To develop and institute a standardized ophthalmology-specific operating room checklist, and to test adherence to the surgical checklist components after implementation.

Design An ophthalmology-specific operative room checklist was developed using recommendations from surgical preoperative checklists from other subspecialties and checklists specific to cataract surgery. This standardized checklist was then implemented into the operating rooms. Operative room staff was trained on its use. Adherence to the checklist was measured prospectively.

Setting Surgical centers at Kellogg Eye Center in Ann Arbor and Livonia, Michigan.

Participants Patients undergoing ophthalmic surgery at the Livonia and Ann Arbor surgical centers.

Main Outcome(s) and Measure(s) The primary outcome measures were surgical team adherence to each category of the operative checklist (preop, prebrief, preanesthesia verification, time-out, intraocular lens measurement/confirmation for cataract cases, debrief). Adherence to the subsections of the operative checklist was measured during three periods over the course of 1 year: baseline, postintervention (after introduction of the checklist in all operating rooms), and postadjustment (after additional training was provided to operating room staff and incentives to collect data were provided to personnel responsible for collecting it).

Results A total of 2,532 surgical cases were included in the analysis. Baseline adherence ranged from 87 to 90% across preop, prebrief, preanesthesia, and time-out verification sections of the operative checklist. After the institution of the intervention and adjustments, adherence to the surgical checklist improved significantly across all areas of the checklist to 97–98% (p < 0.01).

Conclusions and Relevance The development and implementation of an ophthalmology-specific operative room checklist increase adherence to recommended safety checks prior to the start of surgery. To maximize patient safety, the same or similar checklist is recommended for use in all ophthalmology operating rooms.
A monitoring device made of an anodic aluminum oxide template for plasma-induced charging potential measurements in the high-aspect-ratio trench structure
Authors: Park Ji-Hwan , Chung Chin-Wook
Published: November 2018

A monitoring device is proposed to investigate the charge accumulation effects in a high-aspect-ratio trench structure. This monitoring device is made of an anodic aluminum oxide (AAO) template, which is a self-organized material with parallel pores, to demonstrate a high aspect ratio trench structure. A top electrode and bottom electrode were formed in the AAO contact structure for measuring electric potentials. These electrodes can be assumed to be electrically floating due to the very high input resistance of the measurement circuit. Therefore, the electric potentials resulting from the charge accumulation can be measured. In this paper, the fabrication process of the proposed device and experimental demonstrations are presented.
Folding a small protein using harmonic linear discriminant analysis
Authors: Mendels Dan , Piccini Giovannimaria , Brotzakis Z. Faidon , Yang Yi I. , Parrinello Michele
Published: November 2018

Many processes of scientific importance are characterized by time scales that extend far beyond the reach of standard simulation techniques. To circumvent this impediment, a plethora of enhanced sampling methods has been developed. One important class of such methods relies on the application of a bias that is a function of a set of collective variables specially designed for the problem under consideration. The design of good collective variables can be challenging and thereby constitutes the main bottle neck in the application of these methods. To address this problem, recently we have introduced Harmonic Linear Discriminant Analysis, a method to systematically construct collective variables as linear combinations of a set of descriptors. The method uses input information that can be gathered in short unbiased molecular dynamics simulations in which the system is trapped in the metastable states. Here, to scale up our examination of the method’s efficiency, we applied it to the folding of chignolin in water. Interestingly, already before any biased simulations were run, the constructed one-dimensional collective variable revealed much of the physics that underlies the folding process. In addition, using it in metadynamics, we were able to run simulations in which the system goes from the folded state to the unfolded one and back, where to get fully converged results, we combined metadynamics with parallel tempering. Finally, we examined how the collective variable performs when different sets of descriptors are used in its construction.
The large helical device vertical neutron camera operating in the MHz counting rate range
Authors: Ogawa K. , Isobe M. , Nishitani T. , Kobuchi T.
Published: November 2018

In the currently performed neutral beam (NB) -heated deuterium plasma experiments, neutrons are mainly produced by a beam-plasma reaction. Therefore, time-resolved measurement of the neutron emission profile can enhance the understanding of the classical and/or anomalous transport of beam ions. To measure radial neutron emission profiles as a function of time, the vertical neutron camera (VNC) capable of operation with a counting rate in the MHz range was newly installed on the Large Helical Device (LHD). This is the world’s first neutron camera for stellarator/heliotron devices. The VNC consists of a multichannel collimator, eleven fast-neutron detectors, and the digital-signal-processing-based data acquisition system (DAQ). The multichannel collimator having little cross talk was made from hematite-doped heavy concrete, which has a high shielding performance against both neutrons and gamma-rays. A stilbene crystal coupled with a photomultiplier having high-gain-stability in the high-count rate regime was utilized as a fast-neutron scintillation detector because it has a high neutron-gamma discrimination capability at high count rates. The DAQ system equipped with a field programmable logic controller was developed to obtain the waveform acquired with a 1 GHz sampling rate and the shaping parameter of each pulse simultaneously at up to 106 cps (counts per second). Neutron emission profiles were successfully obtained in the first deuterium campaign of LHD in 2017. The neutron emission profile was measured in tangentially co-injected NB-heated plasma with different magnetic axes (Rax). The neutron counts became larger in the inward-shifted configuration, which was consistent with the total neutron rate measured by the neutron flux monitor. The radial peak position of the line-integrated neutron profile which changed according to Rax showed that the VNC worked successfully as designed. The VNC demonstrated the expected performance conducive to extending energetic-particle physics studies in LHD.
Effect of boundary layer thickness on transverse sonic jet mixing in a supersonic turbulent crossflow
Authors: Pizzaia A. , Rossmann T.
Published: November 2018

The surface boundary through which a sonic jet in supersonic cross flow is injected is shown to have a significant effect on the size, penetration, and mixing characteristics of the jet plume. A circular, high-pressure, sonic jet is injected into a M = 3.4 supersonic crossflow through a well-characterized turbulent boundary layer of two different thicknesses (δ/d = 0.6 and 6.1), with variable momentum ratios (J = 1.2, 2.6, and 5). Planar laser Mie scattering of condensed ethanol droplets is used to quantitatively image the injected fluid concentration in both side and end-views at multiple downstream locations. Jet penetration, plume area, and characteristic size and location of regions of intense mixing are compared. The jets injected through the thicker boundary layer are shown to have significantly enhanced jet penetration (∼50%), spread (∼100%), and mixing intensity (∼100%, especially in the near-field) over a wider area of the jet plume. Additionally, characterization of mixing is examined using the variance in the concentration field as well as probability density functions of concentration determined along contours of constant jet fluid concentration. From these results, the jet injections associated with the thicker boundary layer transition from shear dominated mixing zones on the windward side to more distributed mixing zones throughout the plume at earlier downstream locations and show influence of interactions between boundary layer vorticity and vortical structures within the jet leading to larger lateral expansion.
Random sequential adsorption of cuboids
Authors: Cieśla Michał , Kubala Piotr
Published: November 2018

The subject of this study was random sequential adsorption of cuboids of axes length ratio of a : 1 : b for a ∈ [0.3, 1.0] and b ∈ [1.0, 2.0], and the aim of this study was to find a shape that provides the highest packing fraction. The obtained results show that the densest packing fraction is 0.401 87 ± 0.000 97 and is reached for axes ratios near cuboids of 0.75:1:1.30. Kinetics of packing growth was also studied, and it was observed that its power-law character seems not to be governed by the number of cuboid degrees of freedom. The microstructural properties of obtained packings were studied in terms of density correlation function and propagation of orientational ordering.
Estimation of Cell Birth Rate in the Wool Follicle Bulb using Colchicine Metaphase Arrest or DNA Labelling with Bromodeoxyuridine
Authors: Hynd PI , Everett BK
Published: November 2018

The birth rate of cells in the wool follicle cells (CBR) was measured in two experiments on sheep
differing widely in wool growth rate as a consequence of differences in nutritional regime. In Experiment
1, CBR was determined in one sheep on a high and one on a low plane of nutrition by two
methods: the colchicine-metaphase arrest method, or from the product of total cell number and cell
cycle time (the latter determined by DNA labelling with 5-bromo-2'-deoxyuridine (BrdU) and analysis
of the fraction of mitoses labelled curve). CBR by colchicine was 0.73 and 0.56 of that determined
using BrdU for the low- and high-plane sheep respectively. Cell cycle times were 26.5 h (low nutrition)
to 18.6 h (high nutrition). In Experiment 2, CBR was again measured by the colchicine method, and
from the rate of increase in labelled cells following a pulse dose of BrdU, in sheep on two levels of
nutrition (n = 4llevel) and with a 3.7-fold difference in wool growth rate. Again, CBR by colchicine was
only 0.41 (high nutrition) to 0.74 (low nutrition) of estimates made using the BrdU method, this
difference being statistically significant only for sheep on the high plane of nutrition. Nutrition significantly
altered CBR determined by colchicine (Pc0.001) and by BrdU (Pc0.034). The rate of
fibre growth per follicle measured on two separate occasions was closely related to CBR measured
using colchicine (r= 0.83, P< 0.01 and 0.8 1, P c 0.02) or BrdU (r= 0.73, P c 0.04 and 0.64, P< 0.08).
It is concluded that CBR is a major determinant of fibre growth, but that colchicine depresses CBR.
Previous estimates of mitotic activity in wool follicle bulbs have been made using colchicine and are
thus probably underestimated. The technique using BrdU labelling and the subsequent rate of increase
in labelled cells appears to be a useful one for estimating follicle cell kinetics.
Oxidative Damage of Pyrimidine Nucleosides by the Environmental Free Radical Oxidant NO3• in the Absence and Presence of NO2• and Other Radical and Non-Radical Oxidants
Authors: Goeschen Catrin , White Jonathan M. , Gable Robert W. , Wille Uta
Published: November 2018

Analysis of the products formed in the reaction of the environmental free radical oxidant NO3• with permethylated uridine 1 and thymidine 2 in solution revealed highly complex reaction pathways following initial NO3• induced oxidative electron transfer at the pyrimidine ring. Product formation was found to depend not only on the nature of the nucleobase, but also on the presence of other free radical oxidants, namely NO2•. In the reaction of 1 with NO3•, which was generated through CAN photolysis, apart from formation of the highly oxidized nucleoside derivative 4 as the major product, cleavage of the C–N glycosidic bond did also occur, resulting in formation of ribolactone 5 and the free nucleobase 6. The suggested mechanism involves in situ generation of NO2• during the course of the reaction, which promotes conversion of the initially formed radical cation 7 to 4 in an autocatalytic fashion.When the reaction of NO2• with O3 was used to generate NO3•, the initially formed radical cation 7 in the reaction with permethylated uridine 1 is rapidly trapped by NO2• to give 5-nitrouridine 18 in a radical mediated vinylic substitution reaction. In contrast to this, under similar conditions in the reaction involving thymidine 2 the highly oxidized products 20 and 21 are obtained as major compounds, which result from addition to the C5–C6 double bond. No direct reaction between NO3• and the carbohydrate moiety in 1 and 2 was found. Also, no reaction occurred between the nucleosides and mixtures of NO2•/N2O4 and O3/O2, respectively.
The acid-catalysed hydrolysis of α-methylallyl acetate in aqueous solution
Authors: Fredlein RA , Lauder I
Published: November 2018

The kinetics of the
acid-catalysed hydrolysis of a-methylallyl acetate in
aqueous solution have been studied over the range 30-100�. Oxygen-18 tracer
experiments reveal the mechanism to be solely Aac2
and the Arrhenius parameters are consistent with this
conclusion. Crotyl alcohol is observed in the
reaction products. The formation of rearranged
alcohol is explained by allylic isomerization of the α-methylallyl alcohol produced by the hydrolysis.
Phosphato complexes of cobalt(III). IV. Hydrolysis in basic solution
Authors: Lincoln SF , Stranks DR
Published: November 2018

The rates of hydrolysis of phosphato complexes of cobalt(111) in sodium hydroxide concentrations
ranging from 0.02M to 0.37M, and at several ionic strengths, have been measured
with a tracer technique. Bidentate phosphato
complexes exhibit the same rates of hydrolysis as the corresponding monodentate
complexes, due to a rapid conversion of the bidentate into the monodentate
form. The general rate law for
base hydrolysis of all the phosphato complexes is:

d[PO34]/dt = {kH2O
+ kOH[OH-]}[complex]

At 60� and at unit ionic
strength, the rate constants for the complexes cis-[Co(NH3)4OH.PO4]-, cis-[Co en2OH.PO4]-,
and [Co(NH3)5PO4] respectively are: 103kH2O
(min-l) 85.0, 2.0, <1; and 103kOH (1. mole-1
min-l) 42.7, 12.0, 69.5. Mechanistic
conclusions have been based on the measured enthalpies and entropies of
activation and deuterium solvent isotope effects. For all complexes, kH2O is identified with an aquation
mechanism involving synchronous interchange of the phosphate and solvent water
between the first and second coordination spheres of the complexes. In the case of the tetrammine and bis(ethylenediamine)
complexes, kOH is identified with a process involving
synchronous interchange of phosphate and hydroxide ion between the first and
second coordination spheres of the complexes. In the case of the pentammine complex, an SN2CB mechanism is
considered to be more probable. A comparison with the base
hydrolysis of halogen complexes of cobalt(111) is presented.
Near infrared spectra of some cobalt(II) compounds
Authors: Graddon DP , Mockler GM
Published: November 2018

Absorption spectra of
compounds CoX2B2 and CoX2B4 (X = Cl, Br, I, or NCS; B = a heterocyclic
base) have been obtained by reflectance and in solution in the near infrared
region between 1000 and 2000 mμ. The spectra are
characteristic of the stereochemistry of the metal atom: octahedral compounds
have a single absorption band near 1100 mμ, e
< 10; tetrahedral compounds have three overlapping absorption bands near
1100,1400, and 1700 mp, 30 < < 150. Comparisons are made with previously
observed spectra of octahedral and tetrahedral species of the types CoL2+6 and CoX2-4.
Thio derivatives of β-diketones and their metal chelates. IX. Nickel and copper complexes of some new fluorinated monothio-β-diketones
Authors: Ho RKY , Livingstone SE
Published: November 2018

Four new fluorinated monothio-β-diketones of general formula RC(SH)=CH-
COCF3 have been prepared; they are: l,l,l-trifluoro-4-mercapto-4-(4-methylphenyl)but-3-en-2-one (R = p-methylphenyl),
1,1,1-trifluoro-4-mercapto-4- (4-methoxyphenyl)but-3-en-2-one
(R = p-methoxyphenyl), 4-(4-bromophenyl)-l,l,l- trifluoro-4-mercaptobut-3-en-2-one (R = p-bromophenyl), and l,l,l-trifluoro-4-
(2-furyl)-4-mercaptobut-3-en-2-one
(R = 2-furyl). Their nickel complexes, which are
brown and diamagnetic, yield stable high-spin bis-pyridine adducts. When R = p-MeC6H4, p-MeOC6H4,
or p-BrC6H4 the ligand yields
both copper(1) and copper(11) complexes but when R = 2-furyl
only a copper(11) complex is obtained. Infrared data indicate that in the
copper(1) complexes the ligand is coordinated through the sulphur
atom only.
The synthesis of model block copolymers of Poly(cis-1,4-isoprene : styrene)
Authors: Cramond DN , Urwin JR
Published: November 2018

The synthesis of model
block copolymers of poly(cis-1,4-isoprene
: styrene)initiated by butyllithium in the solvent
benzene is described in detail, and the analysis of the microstructure of the polyisoprene sequence discussed. The copolymers were found
to be of narrow distribution in molecular size and composition and the
microstructure was close to that expected from previously published results on
the synthesis of polyisoprenes.
Some tertiary arsine complexes of platinum and palladium
Authors: Nanje Gowda NM , Reddy GKN
Published: November 2018

A series of square-planar
complexes of platinum and palladium of the general formula MX2L2,
where M is Pt or Pd, X is Cl, Br or I, and L is EtPh2As
or PrPh2As, have been made. The platinum complexes (X = Cl or Br) react with the corresponding halogens to give
octahedral complexes of the type PtX4L2. The dichloro
complexes of platinum(II) react with carbon monoxide to give carbonyl complexes
of the type trans- [PtCl(CO)L2]+.
Structures have been assigned to all the compounds.
Synthesis of Cyclododecane-r-1,c-5,c-9-triyl Tris(2,3-dihydroxybenzoate), a carbocyclic analogue of enterochelin
Authors: Collins DJ , Lewis C , Swan JM
Published: November 2018

Reaction of
cyclododecane-r-1,c-5,c-9-triol with 2,3-dimethoxybenzoyl chloride in pyridine
gave cyclododecane-r-1,c-5,c-9-triyl tris(2,3- dimethoxybenzoate),
which upon treatment with 3 mol of boron tribromide at low temperature gave 83%
yield of cyclododecane-r-1,c-5,c-9-triyl tris(2-hydroxy-3-methoxybenzoate).
When 6.5 mol of boron tribromide was used under similar conditions cyclo-dodecane-r-1,c-5,c-9-triyl
tris(2,3-dihydroxybenzoate) was obtained in 77% yield. Some model reactions of
isopropyl 2,3-dimethoxybenzoate with boron tribromide are described.
Synthetic plant growth regulators. II. The preparation of tricyclic helminthosporic acid analogues with gibberellin-like properties
Authors: Mander LN , Prager RH , Turner JV
Published: November 2018

Cyclopropyl ketone (13),
prepared by the copper-catalysed decomposition of diazoketone (12), underwent
specific cyclopropyl bond fission on reduction with lithium in liquid ammonia.
Oxidation of the reaction product mixture followed by catalytic hydrogenation
gave ketone (7) whose stereo-chemistry was established by degradation to trans-decalyl- 9-acetic acid (18), an authentic sample of which
was prepared from trans-decalin-9-carboxylic acid. Ketone (7) was converted via
its methylene derivative (21) to the pyrrolidinium
salt (24) which underwent base induced [2,3]sigmatropic rearrangement, followed
by hydrolysis, to give aldehyde (26). Acid (5) was formed by simple oxidation
and converted by base catalysed isomerization of its methyl ester, then
hydrolysis, into acid (6).
Temperature dependence of the formation of Tris[2,3-bis(2-pyridyl)pyrazine]-iron(II)
Authors: Guerney PJ , Knight RJ , Sylva RN
Published: November 2018

The overall formation
constant, β3, of tris[2,3-bis(2- pyridyl)pyrazine]iron(II) was
determined spectrophotometrically at 25, 40, 60 and 80�C as 8.9 x 107,
2.9 x 107, 1.0 x 107 and 1.8 x 106 (mol l-1)-3
respectively at pH > 5.5. The pKa of the ligand is 3.1 at 25�C
and decreases to about 2.0 at 80�C. The variation of β3 with
temperature is attributed to differences in the temperature dependence of the
rate constants of the complex formation process and of dissociation. The
overall energy of activation for complex formation is -870 J mol-1.
The complex dissociates according to first order kinetics with rate constants
of 4.3 x 10-3 s-1 and 6.8 x 10-2 s-1
at 25 and 35�C respectively, and the activation energy of the dissociation
reaction is about 3000 J mol-1. The molar absorptivity of the
complex, 11000 1. mol-1 cm-1 at the absorption maximum
(λmax 535 nm), is independent of temperature from 25 to 80�C.
Chemical Studies on Pentacyclic Triterpenes. IV. Determination of the Configuration of the 2-Acetyl Group in Methyl 2ξ-Acetoxy-20β-hydroxyursonate
Authors: El-Garby  Younes M
Published: November 2018

The acetoxyl
group at position 2 in methyl 2ξ-acetoxy-20β- hydroxyursonate
isolated from the ether extract of defatted apple peels was shown by chemical
reactions to possess the α (equatorial) configuration.
Steric Modification of M-P Bond Lengths: Crystal and Molecular-Structures of the Platinum(II) Complexes trans-(PPrI3)2ClnH2-nPtII (N = 0-2)
Authors: Robertson GB , Tucker PA , Wickramasinghe WA
Published: November 2018

Crystal structure analyses of the square-planar platinum complexes trans-(PPri3)2ClnH2-nPtII(n = 0-2) (C), (B), (A) are described. Diffraction data were recorded at room temperature with a Picker FACS-1 diffractometer. Convergence R values, for reflection numbers given in parentheses, are 0.020 (2373), (A), 0.021 (5771), (B) and 0.018 (1982), (C). The ligand conformation about the Pt-P bonds is perpendicular for (A) and (B) and eclipsed for (C). The Pt-P distances decrease systematically with increasing hydride content [2.339(1)Ǻ, (A); 2.286(1)Ǻ, (B); 2.252(1)Ǻ, (C)]. The decrease reflects the low steric requirement of hydride vis a vis chloride ligands and concomitant changes in anionic ligand/phosphine substituent non-bonding interactions. The trans-bond lengthening of the Pt- Cl bond in (B)(due to trans hydride) is 0.092(1)Ǻ.
Terpenoid Constituents of Morphologically Similar Sponges in the Family Aplysillidae
Authors: Karuso P , Bergquist PR , Cambie RC , Buckleton JS , Clark GR , Rickard CEF
Published: November 2018

The sponge Darwinella sp, contains the known compounds ambliofuran (4) and aplysulphurin (3), and the new compound tetrahydroaplysulphurin-1 (5). Darwinella oxeata collected from various locations around New Zealand, contains aplysulphurin (3) and the new compounds tetrahydroaplysulphurins-1 (5), -2 (6), and -3 (7). Dendrilla rosea which is morphologically similar to the Darwinella sp. above, contains the known compounds ambliofuran (4), aplyroseols-1 (8),-2 (9),-3 (10),-5(11),-6 (12), and -7(15), as well as the new compounds dendrillol-1 (13), dendrillol-2 (14), dendrillol-3 (17) and dendrillol-4 (18). The structure of dendrillol-1 (13) has been confirmed by a single-crystal X-ray determination.