bluuebunny/crossref_metadata_2025 huggingface dataset:
Construction and tests of the research stand with built-in correctors for the detection of gas outflow from long pipelines
Authors: Golak Karol , Lindstedt Paweł , Bartoszewicz Błażej
Published: July 2018

The localization and identification of small gas leaks from a damaged gas pipeline is a very important but at the same time problematic and difficult process to carry out. Quick identification, estimation and precise localization of the leak leads to minimizing the financial and equipment losses resulting from damage. The most commonly used continuous internal methods of leak identification are based on pressure and mass intensity measurements flow at various places in the pipeline. The article presents a description of the construction of a test stand characterized by the correctors built in it and the examples of the signals obtained from its tests for different values of simulated leaks. The results obtained will be used to develop a new method for identifying and locating leakages from long pipelines. This method is based on the cross power spectral density of measured pipeline standard signals (pressure and mass flow) and the membrane displacement signals delivered from the test equipment (correctors) connected to the system.
The impact of a vehicle braking system state on safe driving – part one
Authors: Aleksandrowicz Piotr
Published: July 2018

The state of a vehicle braking system is one of the key factors determining the safety of the driver, passengers and other road users. During operation of a vehicle, the elements of its braking system undergo the process of wear and they are exposed to damage. Deterioration of the braking system efficiency has a direct impact on the collision speed. Thus, diagnosing a braking system during a vehicle operation is of key importance. Therefore, the authors of this article have undertaken the task to identify the influence of the state of a braking system particular element on the collision speed and kinetic energy of the impact. The obtained results of simulation calculations have proven a significant role of a braking system diagnosing in elimination of vehicles whose braking systems do not function properly as using inefficient brakes poses a significant threat to road traffic users and vehicles.
The assessment of the impact of the chosen exploational conditions of hydraulic arrangement on the working liquid condition
Authors: Wilczarska Joanna , Kuliś Ewa , Łukasiewicz Marcin , Fornal Łukasz , Dluhunovych Natalia
Published: July 2018

Hydraulic systems in modern vehicles and agricultural machines have many components. In order to achieve high efficiency of the system, the system requires an accurate filtration system that allows you to reduce the amount of contaminants. Therefore, an important aspect is to determine the content of impurities in the working liquid, so we can diagnose and then predict the durability of the entire hydraulic system. This paper presents selected methods and means of state assessment, as well as the methodology for testing the working fluid. The results of experimental studies conducted in accordance with the developed methodology have been presented, which made it possible to obtain an appropriate analysis of results and draw appropriate conclusions. The results of the research confirmed the validity of the research activities undertaken using the passive experiment.
The use of thermography in the diagnosis of ship piston internal combustion engines
Authors: Monieta Jan
Published: July 2018

The intensity of infrared radiation emitted by objects depends mainly on their temperature. One of the diagnostic signals may be the temperature field. In infrared thermography, this quantity is used as an indicator of the technical condition of marine objects. The article presents an overview of the use of infrared thermography for the diagnosis mainly of marine piston floating objects and various types of reciprocating internal combustion engines as well as examples of own research results. A general introduction to infrared thermography and common procedures for temperature measurement and non-destructive testing are presented. Experimental research was carried out both in laboratory conditions and in the operating conditions of sea-going vessels. Experimental studies consisted of the presentation of photographs of the same objects made in visible light and the use of infrared thermography. The same objects were also compared, but for different cylinders of the tested internal combustion engines as well as for the up state and fault state. The characteristics of the temperature values at selected points were taken depending on the engine load along with the approximation mathematical models of these dependencies.
Mathematical models of changes in the surface layer of frictional pairs as a tool to optimize the wear process
Authors: Matuszewski Maciej , Słomion Małgorzata , Mazurkiewicz Adam , Pimenov Danil Yu.
Published: July 2018

The paper presents mathematical models developed on the experimental studies whose purpose to determine the relationship between studied factors and changes occurring in the surface layer. Developed polynomials allowed to determine expected changes appearing under the influence of external forces in the surface layer of working elements as a kinematic pair with a conformal contact. Therefore, it is possible to control the operation process to minimize changes in the surface layer, so the structural features of kinematic pair stay unchanged in the entire period of work.
Usability Techniques Possible to Use in Diagnostic Tools Interface Improvement
Authors: Bielski Ryszard , Kufel Karol , Bielski Marcin , Jantanata Hendra , Graul Cezary
Published: July 2018

The development of diagnostic tools has caused a rapid increase in the amount of information generated and presented, necessitating the use of computer displays as an interface to data presentation and the use of modern diagnostic tools. The paper presents methods for testing usability that can be used in designing and improving the quality of interfaces of modern diagnostic tools that use communication through graphical user interfaces.
The decision making process of a state technical facilities based on rough set and vibroacoustic estimates
Authors: Boniecki Rafał , Miciak Mirosław
Published: July 2018

The article presents idea and develops of an algorithm to support decision-making process for assessment a technical object state, based on vibroacoustic signals and rough set theory. The article discusses how to implement the main elements of the proposed system using Java technology, with Swing graphics library and JFreeChart component. FirebirdSQL engine was used to be a data base for the objects of diagnosis. JDBC technology will be used for generating queries and communication between the application and database.
Measures of the vibration function pass in the wall element diagnostic test
Authors: Lubos Daniel , Żółtowski Mariusz
Published: July 2018

Building constructions as well as their constituent structural elements must meet the strength requirements, which will not jeopardize the safety of their use. As part of the research experiment, the focus was on the issue related to strength testing properties of masonry elements using a non-invasive test method involving the measurement of vibrations. 40 samples of bricks. Half of them were deliberately damaged so that it would be possible to assess the suitability of the measurement method used and its variability resulting from damage to the masonry element.
Application of harmonic balance method for solving non-linear equations of motion
Authors: Kostek Robert
Published: July 2018

This article presents the advantages and limitations of a harmonic balance method applied for solving non-linear equations of monition. This method provides an opportunity to find stable and unstable periodic solutions, which was demonstrated for a few equations. An error of solution decreases rapidly with increase of number of harmonics for smooth time history of acceleration, which shows convergence; whereas, for discontinuous time histories, this method is not effective.
Laktatazidose – Update 2018
Authors: Kluge Stefan , de Heer Geraldine , Jarczak Dominik , Nierhaus Axel , Fuhrmann Valentin
Published: July 2018

Was ist neu?

Schwere Hyperlaktatämie bei Intensivpatienten Die Ursachen dafür sind vielfältig, am häufigsten liegen eine Sepsis bzw. ein septischer, kardiogener oder hämorrhagischer Schock vor. Eine Hyperlaktatämie ist ein unabhängiger Prädiktor für Versterben bei verschiedenen Gruppen kritisch kranker Patienten. Bei Serum-Laktatwerten > 10 mmol/l sterben 80 % der Patienten auf der Intensivstation. Persistiert die schwere Laktatazidose über 48 Stunden, so sterben alle Patienten. Erhöhte Laktatwerte erfordern eine umgehende diagnostische Abklärung und Einordnung.

Sepsis und septischer Schock Die neue Definition der Sepsis erfordert für den septischen Schock ein Serum-Laktat von > 2 mmol/l bei adäquater Volumensubstitution sowie eine Vasopressoren-Gabe, um bei persistierender Hypotonie einen mittleren arteriellen Druck ≥ 65 mmHg zu erzielen. Das 2018 publizierte „1-Stunden-Bündel“ der Surviving-Sepsis-Campaign empfiehlt als erste Maßnahme die Bestimmung des Laktatwertes – erhöhte Laktatwerte müssen engmaschig kontrolliert werden. Zudem werden die Abnahme von Blutkulturen, die Gabe eines Breitspektrum-Antibiotikums sowie die Gabe von Flüssigkeit und Vasopressoren in der ersten Stunde empfohlen. Die Gabe von Kristalloiden wird bei einem erhöhten Laktatwert (Laktat ≥ 4 mmol/l) oder bestehender Hypotension empfohlen, die Flüssigkeitsgabe kann anhand der Laktat-Clearance ausgerichtet werden.

Laktat bei Lebererkrankungen Bei Patienten mit einer Leberfunktionseinschränkung ist der Laktatmetabolismus verzögert. Der Laktatwert bei Aufnahme auf die Intensivstation ist bei Leberzirrhose signifikant mit der Anzahl an versagenden Organen sowie der Mortalität assoziiert. Die 12-Stunden-Laktat-Clearance hat bei Ausgangslaktatwerten von über 5 mmol/l eine starke prädiktive Aussage für das Überleben, welche auch nach Korrektur für die Schwere der zugrunde liegenden Erkrankung ein unabhängiger Prädiktor bleibt. Je stärker der Abfall des Laktats innerhalb der initialen Therapie war, desto besser ist das Outcome.
Die therapeutische Beziehung im forensischen und allgemeinpsychiatrischen Setting
Authors: Otte Stefanie , Streb Judith , Rasche Katharina , Franke Irina , Nigel Stefanie , Segmiller Felix , Sosic-Vasic Zrinka , Vasic Nenad , Dudeck Manuela
Published: July 2018

Einleitung Da die therapeutische Beziehung im Maßregelvollzug bzw. in der Forensischen Psychiatrie aufgrund des Zwangscharakters sowie der Doppelrolle des Therapeuten als Behandler und als Sachverständiger besonders belastet ist, wurde die therapeutische Beziehung im Maßregelvollzug mit der therapeutischen Beziehung in der Allgemeinpsychiatrie verglichen.

Material & Methoden 52 Patienten des Maßregelvollzugs und 65 Patienten der Allgemeinpsychiatrie beantworteten das Psychopathy Personality Inventory – Revised (PPI-R), das Inventar zur Erfassung interpersonaler Probleme - Deutsche Version (IIP-D), den Fragebogen zur Erfassung der Psychotherapiemotivation (FPTM) sowie das Working Alliance Inventory – Short Revised (WAI-SR). Statistisch wurden deskriptive Analysen durchgeführt, univariate t-Tests, multivariate T-Tests sowie verallgemeinerte lineare Modelle gerechnet.

Ergebnisse Die Qualität der therapeutischen Beziehung wird von den Patienten des Maßregelvollzugs genauso positiv wahrgenommen wie von den Patienten der Allgemeinpsychiatrie. Patienten des Maßregelvollzugs sind tendenziell sogar eher davon überzeugt, dass die in der Therapie angewandten Techniken der Erreichung ihrer Therapieziele dienen.

Diskussion Die therapeutische Beziehung im Maßregelvollzug ist genauso tragfähig wie in der Allgemeinpsychiatrie. Dies könnte auf die längeren, zumeist mehrjährigen Unterbringungszeiten im Maßregelvollzug zurückgeführt werden, in deren Rahmen deutlich mehr Zeit auf den Beziehungsaufbau verwendet werden kann als im Rahmen einer zeitlich auf wenige Wochen begrenzten Therapie in der Allgemeinpsychiatrie.
Komplizierte Zeckenstich-Rickettsiose nach Safari-Tour in Südafrika
Authors: Lang Susanne , Bergmann Tobias , Kuschel Diana-Maria , Schiffl Helmut
Published: July 2018

Anamnese und klinischer Befund Ein 41-jähriger, bis dato gesunder Mann zog sich während einer Safaritour im Krüger Nationalpark einen Zeckenstich zu. 5 Tage später bekam er hohes Fieber mit schwerem Krankheitsgefühl. An der Zeckenstichstelle entwickelte sich ein charakteristisches Ulkus mit schwärzlichem Grund, Schorfbildung und rotem Hof (Eschar, Tache noir). Reise -und Zeckenstichanamnese legten den Verdacht einer Rickettsiose nahe.

Untersuchungen und Diagnose Die Diagnose einer Rickettsiose aus der Zeckenstichfiebergruppe (spotted-fever-group) wurde serologisch bestätigt. Der klinische Verlauf der Rickettsiose wurde durch eine Myokarditis kompliziert, die zunächst nur durch ein erhöhtes Troponin-I auffiel und später mittels Kardio-MRT bestätigt wurde. Der komplizierte Verlauf und der singuläre Eschar sprechen für eine Infektion mit Rickettsia conorii.

Therapie und Verlauf Es kam es zu einer raschen Rückbildung der Symptome der febrilen Infektionserkrankung unter der Therapie mit Doxycyclin. Die Rekonvaleszenz der importierten Reisekrankheit war durch die Myokarditis verzögert.

Folgerung Rickettsiosen sollten bei Afrikareisenden differenzialdiagnostisch in Erwägung gezogen werden. Sie verlaufen in der Regel mild; komplizierte Verläufe können auch bei gesunden jungen Menschen auftreten.
Centella asiatica – Indischer Wassernabel, Tigergras, Gotu Kola, Bua Bok
Authors: Burri Josef , Uehleke Bernhard
Published: July 2018

Centella asiatica (L.) Urb.
Abb. 1
gehört zur Familie der Doldenblütler. Die Pflanze ist u. a. in der indischen, nepalesischen, indonesischen, thailändischen und chinesischen Medizin in Gebrauch. Sie findet sich auch auf der nationalen Liste der wichtigen Arzneimittel Thailands wegen ihren antipyretischen und wundheilenden Eigenschaften. Die Abteilung für die Entwicklung von thailändischer traditioneller und alternativer Medizin nennt Centella asiatica als eines von 5 pflanzlichen Ausgangsprodukten, die sich für die kommerzielle Nutzung eignen.
Fibrin Detected in Plasma of Patients with Disseminated intravascuiar Coagulation by Fibrin-specific Antibodies Consists Primarily of High Molecular Weight Factor XIIIa-crosslinked and Plasmin-modified Complexes Partially Containing Fibrinopeptide A
Authors: Pfitzner Susanne A , Dempfle Carl-Erik , Matsuda Michio , Heene Dieter L
Published: July 2018

Pooled plasma from 40 patients with severe disseminated intravascuiar coagulation (DIC) secondary to septic conditions was subjected to gel permeation chromatography on Sephacryl S-500 HR after sample pretreatment with KSCN for dissociation of non-covalent fibrin complexes. Fibrin antigen in eluates was detected by an array of ELISA tests, using two monoclonal antibodies against fibrin degradation product D-dimer, a monoclonal antibody against an epitope generated by plasmin cleavage of the D-domain, and an antibody against the neo-N- terminus of the α-chain of fibrin exposed by cleavage of fibrinopeptide A. Tag antibodies were a polyclonal antibody against the fibrinogen/ fibrin D-domain, a POD-conjugated version of the monoclonal antibody against fibrin α-chain neo-N-terminus, and a polyclonal antibody against fibrinopeptide A. Most fibrin-related material present in the pooled DIC plasma was of higher molecular mass than fibrinogen. Fibrin polymers were reactive with antibodies against D-dimer, plasmin cleaved D-domain, and fibrin α-chain neo-N-terminus. Part of the polymers reacted with antibodies against fibrinopeptide A, indicating presence of fibrinogen or desA-fibrin monomer within the covalently linked complex. In conclusion, the primary analytes detected by monoclonal antibodies for D-dimer, plasmin-specific epitopes of fibrin degradation products, as well as sites exposed by fibrinopeptide cleavage in plasma from patients with disseminated intravascuiar coagulation are high molecular weight factor XIIIa-crosslinked fibrin complexes, containing plasmin-cleaved D-domains, intact fibrin monomer units, and fibrinogen or desA-fibrin monomer.
Arg506 to Gin Mutation in the Factor V Gene Causes Poor Fibrinolytic Response in Children after Venous Occlusion
Authors: Nowak-Göttl Ulrike , Binder Martha , Dübbers Angelika , Kehrel Beate , Koch Hans-Georg , Veltmann Hildegard , Vielhaber Heinrich
Published: July 2018

To determine to what extent the Arg506 to Gin mutation in the factor V gene influences the fibrinolytic response after 20 min venous occlusion (VO) we investigated a population of APC resistant children (n = 60) and a group of age-matched healthy controls (n = 25). After 20 min VO, symptomatic (n = 30) carriers of the common factor V mutation showed significantly reduced t-PA activities compared with asymptomatic (n = 30) carriers (p <0.0001) and healthy controls (p <0.0001). In contrast, PAI1 activity was significantly (p <0.0001) higher before and after VO in children with the factor V mutation compared with healthy children. No difference was found between symptomatic and asymptomatic probands. A significantly lower PAI 1 antigen decrease along with a lower t-PA antigen release was found in the APC resistant children compared with the controls. No significant difference was seen between individuals with and without previous vascular insults. As the lack of t-PA activity after VO in symptomatic carriers is the most conspicuous result, we suggest that the factor V gene mutation itself might induce the fibrinolytic impairment by increasing the thrombin levels and thus increasing the recently described thrombin-activable fibrinolysis inhibitor (TAFI).
Bilateral Extensive Ossification of the Posterior Petroclinoid Ligament: An Anatomical Case Report and Literature Review
Authors: Haładaj Robert , Polguj Michał , Żytkowski Andrzej , Topol Mirosław , Wysiadecki Grzegorz
Published: July 2018

Background The posterior petroclinoid dural fold (commonly referred to as a ligament) forms the roof of the trigeminal porus and the roof of the petroclival venous confluence. It lies in close proximity to the oculomotor nerve that crosses it. Due to the low availability of research material, only a few cadaveric studies have been conducted on the microsurgical anatomy of the petroclinoid ligament in cases of its ossification. Thus our report complements earlier studies and provides detailed data on the spatial relationships between the ossified posterior petroclinoid ligament and the trigeminal, oculomotor, and abducens nerves, with special attention to the topographical relationships within the petroclival venous confluence and Dorello's canal.

Case Description Bilateral massive ossification of the posterior petroclinoid ligament was observed during the dissection of a 76-year-old female cadaver. The presence of an osseous bridge over the trigeminal notch was also detected on the left side. No narrowing of the space occupied by the petroclival venous confluence was observed. However, the dural sheath of the oculomotor nerve was fixed much more than usual.

Conclusions Because the ossification of the posterior petroclinoid ligament may be considered a factor influencing diagnostic and surgical procedures, neurosurgeons and neuroradiologists should be aware of this variation. Ossification of the posterior petroclinoid ligament may also potentially result in greater susceptibility of the oculomotor nerve to injury.
Investigation and Evaluation of Potential Aerosol Release by Maquet/Getinge Heater–Cooler Units Used during Cardiac Surgery
Authors: Schwandtner Sebastian , Reichel Herwig , Jatzwauk Lutz , Matschke Klaus
Published: July 2018

Background Heater–Cooler units (HCUs) supply tempered water through blood heat exchangers and through warming/cooling blankets to control the body temperature of heart surgery patients. Bacteria which potentially colonize the stored water may escape from the tank into the environment and are carried by the device's cooling air exhaust into the sterile field and finally may infect open chest heart surgery patients. Reports from several countries are connecting the infection of open chest heart surgery patients to airborne transmitted Mycobacteria chimaera which were found in the water of heater–cooler devices. As a consequence of the vigilance system for medical products, we investigated the potential release and the possible transmission of bacteria from the tank water into the sterile operating field.

Materials and Methods In the absence of an evaluation standard for this problem, measurable acceptance criteria for particle releases and a qualitative method for bacteria transmission assessment have been deployed. To assess potential bacteria transmission into the sterile field, tank water of the test devices was inoculated with high concentrations of Pseudomonas aeruginosa (reference strain ATCC15442) and operated in an operating room with simulated use.

Results The particle release at the tank lids of the Maquet/Getinge HCU 30 and HCU 40 during the filling of the tubes with water (deaeration) and during the removal of water from the tubes (emptying) increased slightly, but close to the blank readings for the larger particles. As expected, the particle release at the cooling air grids was higher than around the tank openings. Consistent with the particle measurements, no bacteria from the tank water were found in the sterile field during simulated use of all highly inoculated machines in an operating room.

Conclusion In summary, we assess the risk of infecting open chest heart surgery patients with aerosol-transmitted bacteria from water inside the Maquet/Getinge HCU 40, HCU 30 to be negligible, if handled in accordance with common clinical hygienic precautions.
A Report of Five Child Tetanus Cases
Authors: Boyarchuk Oksana , Volyanska Lubov , Synytska Vira , Korytsky Grygoriy , Burbela Emilia
Published: July 2018

We present five cases of generalized tetanus in children 5 to 13 years old, who were admitted to the intensive care unit of Ternopil Regional Children's Hospital (Western Ukraine) during the past 6 years (2012–2017). In our study, four children were unvaccinated and one received the full series of vaccinations. Proper vaccination in cases of infected wound may not prevent the development of the disease but improves the prognosis for recovery. Treatment of tetanus in Ukraine requires standardization of treatment protocols according to the World Health Organization recommendations, including making human tetanus immune globulin available, as specified by evidence-based medicine. Vaccines availability and education of physicians and parents about the benefits of immunization should be priority national health measures to prevent tetanus.
Zwangsbehandlung in der Psychiatrie und Selbstbestimmungsfähigkeit: Anthropologie einer Grenzbegegnung
Authors: Valdes-Stauber Juan
Published: July 2018

Hintergrund Selbstbestimmungsfähigkeit wird in der Psychiatrie relevant, wenn eine Behandlung aus medizinischer Sicht geboten wäre, aber gleichzeitig gegen den natürlichen Willen des Patienten erfolgen müsste. Eine substitutive Entscheidung bedarf sodann einer normativen Begründung.

Fragestellung Kann die Dialektik zwischen der vom Patienten subjektiv erlebten Entscheidungsgewissheit und der medizinisch gebotenen fürsorglichen Zwangsbehandlung als substitutive Entscheidung, bei angenommener Selbstbestimmungsunfähigkeit seitens des Patienten und zugleich geltendem Gebot der Behandlung bei vorausgesetztem mutmaßlichen Willen, in medizinanthropologischer Sicht reformuliert werden?

Methode Nach Abgrenzung juristischer Begriffe werden Annahmen, die der kanonischen Auffassung von individueller Autonomie zugrunde liegen, herausgearbeitet. Anschließend wird eine Anthropologie des Begegnungsraumes bei Anwendung unfreiwilliger, aber medizinisch gebotener Maßnahmen, ausgehend von der gegebenen Behandlungs(a)symmetrie und der potentiellen Resonanzfähigkeit, entworfen. Auf dieser Basis wird eine Kritik der rein monistischen Auffassung des psychisch Kranken, ohne Berücksichtigung von sozialer Verwobenheit, begründet. Die Argumentation führt zu einer Pragmatik der umsichtigen Entscheidungen unter Unsicherheit.

Ergebnisse Selbstbestimmungsfähigkeit als normatives Konzept meint die Sicherstellung der Entscheidungsautonomie als Fähigkeit der umsichtigen Selbstfürsorge. Sie ist als Ergebnis einer ausgewogenen Urteilsfähigkeit der eigenen Intentionen aufzufassen, die eine kontextuelle Erwägung der Kontingenzen und eine Vorausschau der Handlungskonsequenzen berücksichtigt. Die kanonische Dialektik zwischen Souveränität (entsprechend Selbstbestimmungsfähigkeit) und Subsidiarität (entsprechend substitutiver Entscheidung) basiert im hier vorgeschlagenen Modell auf der Annahme von Behandlungsasymmetrie und personaler Resonanzfähigkeit. Bei der Erwägung von substitutiven Entscheidungen sollten die haltgebenden sozialen Mikrosysteme des Patienten Berücksichtigung finden.

Diskussion Die anthropologische Auseinandersetzung mit der Dialektik zwischen Selbstbestimmung und substitutiver Entscheidung führt eher zu einer Besinnung auf individuelle Lösungen mit ungewissem Ausgang als zu kategorischen Entscheidungen. Alle an der substitutiven Entscheidung Beteiligten und relevante Dritte sollten im Prozess der Entscheidungsfindung Berücksichtigung finden.
Two dimensional numerical modelling and analysis of a novel electromagnetic inductive valve
Authors: Guo Dawei , Cheng Mousen , Yang Xiong , Li Xiaokang , Wang Moge
Published: July 2018

A novel type of electromagnetic inductive valve has been developed for the gas injector of the planar pulsed inductive plasma thruster. However, due to the complex operation process of the valve, the design work and the performance prediction can only be accomplished by experimentation. This paper explains a two dimensional model applied to predict the valve performance. The electromagnetic and mechanical aspects which dominate the valve operation process are treated as two weakly coupled problems. The equivalent circuit method is applied to analyze the electromagnetic problem where the valve is represented by a series of sub-conductors. The Lorentz force is calculated and introduced into the mechanical problem as an analytical load. Simulation and experimental validations are implemented in a prototype valve. Compared results from experiments convince that the present model can be used to predict the valve dynamic performances with satisfying accuracy. Moreover, the detailed insight with respect to the development of magnetic flux density, induced current, Lorentz force and velocity of the diaphragm is presented to better understand the valve operation process. The results indicate that the effective acceleration of the diaphragm occurs in the initial phase of valve opening. Only the diaphragm obtains enough kinetic energy during the first half cycle of the coil current, can the valve be fully opened.
Development and modeling of a polar-direct-drive exploding pusher platform at the National Ignition Facility
Authors: Ellison C. Leland , Whitley Heather D. , Brown Colin R. D. , Copeland Sean R. , Garbett Warren J. , Le Hai P. , Schneider Marilyn B. , Walters Zachary B. , Chen Hui , Castor John I. , Craxton R. Stephen , Gatu Johnson Maria , Garcia Emma M. , Graziani Frank R. , Kemp G. Elijah , Krauland Christine M. , McKenty Patrick W. , Lahmann Brandon , Pino Jesse E. , Rubery Michael S. , Scott Howard A. , Shepherd Ronnie , Sio Hong
Published: July 2018

High-intensity laser facilities, such as the National Ignition Facility (NIF), enable the experimental investigation of plasmas under extreme, high-energy-density conditions. Motivated by validating models for collisional heat-transfer processes in high-energy-density plasmas, we have developed an exploding pusher platform for use at the NIF in the polar-direct-drive configuration. The baseline design employs a 3 mm-diameter capsule, an 18 μm-thick CH ablator, and Ar-doped D2 gas to achieve several keV electron-ion temperature separations with relatively low convergence ratios. In an initial series of shots at the NIF—N160920–003, -005, and N160921–001—the ratio of the laser intensity at different polar angles was varied to optimize the symmetry of the implosion. Here we summarize experimental results from the shot series and present pre- and post-shot analysis. Although the polar-direct-drive configuration is inherently asymmetric, we successfully tuned a post-shot 1D model to a set of key implosion performance metrics. The post-shot model has proven effective for extrapolating capsule performance to higher incident laser drive. Overall, the simplicity of the platform and the efficacy of the post-shot 1D model make the polar-direct-drive exploding pusher platform attractive for a variety of applications beyond the originally targeted study of collisional processes in high-energy-density plasmas.
High resolution, high efficiency liquid scintillator capillary array for gamma imaging
Authors: Zhang Mei , Hu Huasi , Li Kuinian , Peng Bodong , Sheng Liang , Hei Dongwei , Li Yang
Published: July 2018

We fabricated a liquid scintillator capillary array (LSCA) for gamma imaging with the aim of developing a one-dimensional detector system utilizing a streak camera for high temporal and spatial resolution pulsed gamma radiation detection. The detector’s performance was studied in a simulation and via an experiment. The maximum efficiency of the LSCA’s emission was at a wavelength of 420 nm. To establish a high fidelity representation of the detector’s edge spread function and modulation transfer function (MTF), a slanted edge algorithm was introduced to calculate the edge spread function of the discrete sampling array’s image screen. The simulation results showed that the spatial resolution of the LSCA was better for 14 MeV neutrons than for 1.25 MeV gamma radiation. The experimental results show that in comparison with a 6-mm-thick LaBr3 image plate, the LSCA had a higher temporal and spatial resolution when used as a gamma detector. The spatial resolution was 1.1 lp/mm (MTF = 0.1) for the LSCA. In addition, when an ultra-violet streak camera was coupled with the LSCA, it had a comparable sensitivity to that of a 6-mm-thick LaBr3 image plate.
Solutions of nonplanar KP-equations for dusty plasma system with GE-method
Authors: Reyad S. , Selim M. M. , EL-Depsy A. , El-Labany S. K.
Published: July 2018

The propagation of three-dimensional nonlinear dust acoustic waves in a dusty plasma consisting of positive and negative dust grains as well as Boltzmann distributed electrons and ions is investigated. Using a reductive perturbation method, Cylindrical Kadomtsev-Petviashvili and Spherical Kadomtsev-Petviashvili equations, appropriate for describing the evolution of the system, are derived. The Generalized Expansion method is used to find the various solutions of the obtained nonlinear Kadomtsev-Petviashvili equations. New classes of triangular, hyperbolic solitary, rational, and Jacobi elliptical type solutions are obtained and graphically presented. It is found that the proposed dusty plasma model can support solitary waves with compressive and rarefactive potential pulses. Moreover, the effects of plasma parameters on this solitary wave structure are investigated. The current findings are applied to a cosmic-type plasma in different regions of space, viz. cometary tails, mesosphere, and Jupiter's magnetosphere as well as laboratory-type plasma such as low temperature experiments, where a dusty plasma with opposite polarity is dominant.
Numerical simulation and analysis of passive intermodulation caused by multipaction
Authors: Zhang Lei , Li Yongdong , Lin Shu , Wang Hongguang , Liu Chunliang , Li Jun , Xu Zhuo
Published: July 2018

In this paper, emphasis is put on passive intermodulation (PIM) caused by multipaction. The results are calculated by particle-in-cell simulation under the conditions of 2-tone and 4-tone carriers. A temporal evolution of the number of particles with different carrier powers is presented. The input and output signals in the time domain and the power spectrum densities of these signals in the frequency domain under different conditions are compared. The relationship between multipaction and PIM interference is discussed. It shows that the appearance of the PIM phenomenon follows the occurrence of saturation of multipactor discharge and the powers of PIM products basically increase as the carrier powers grow. In addition, to suppress the occurrence of PIM interference, an external magnetic field is added in the direction perpendicular to the electric field, which is a practical way to inhibit multipaction, and the effectiveness and the reliability of this method are also verified by simulation.
Finite element analysis of effects of Joule heating, electro-osmosis and slip conditions on the performance of magnetohydrodynamic (MHD) micropumps
Authors: Li Qiang , Yu Ming-Fu , Li Jie , Zhang Xiao-Chen , Sun Hong
Published: July 2018

Magnetohydrodynamic (MHD) micropump which is energy saving and less pollution has been widely investigated by researchers in recent years. Based on the finite element analysis (FEA) of numerical model of 3D MHD micropump, we investigated the comprehensive effects of Joule heating, electro-osmosis and slip condition at walls on flow performance. This paper presents a new method for solving the full 3D MHD equations by coupling multi-physics fields, and gives a more comprehensive analysis of fundamental principles of MHD micropump. The temperature distribution under different flow channel geometries, the electro-osmotic velocity in MHD micropump, and the influence of slip condition at walls on flow velocity are analyzed in detail. The flow velocity slightly increases when taking the effect of Joule heating into account. In addition, the flow velocity is hardly affected by electron-osmosis in this work. It should be pointed out that the mean temperature of MHD micropump decreases with driven voltage increasing. With the advantage of fast and accurate analysis of MHD micropump performance, this study holds promising potential for the optimal design and fundamental research of MHD micropump.
Seesaw type actuator using balancing between electrostatic force, elasticity, and gravity
Authors: Song Kahye , Cha Youngsu
Published: July 2018

Actuators are becoming more diverse in shape and have diverse applications. New techniques and materials have been adapted to numerous actuators with novel structures. In this study, a new actuator with a seesaw structure was proposed and fabricated. This actuator has a relatively simple design utilizing electrostatic attraction, and it can be easily controlled by an external electrical input. Interestingly, the actuator is operated by force balancing between electrostatic attraction, elasticity, and gravity. We present a physics-based model describing the operation of the actuator. We validated the theoretical model through comparison with experiments. The theoretical expectations and experimental results agree well with some discrepancy at particular frequencies under one hertz.
Experimental study and analytical modelling of the effect of the driving frequencies on dual frequency capacitively coupled plasmas
Authors: Saikia P. , Bora B. , Schulze J. , Bhuyan H.
Published: July 2018

A capacitively coupled radio frequency discharge driven by two harmonics substantially different from each other allows some degrees of independent control of the ion energy and ion flux. The low frequency (ωLF) source controls the ion energy, while the ion flux is controlled by the high frequency (ωHF) source. The choices of the driving frequencies can influence the properties of the dual frequency capacitively coupled plasmas (2f CCP). Here, we study the effect of the driving frequencies on the properties of the 2f CCPs, i.e., on the generation of a DC self-bias, the excitation of the non-linear Plasma Series Resonance (PSR) effect as well as the independent control over the mean ion energy and the flux in three different 2f CCP experiments: namely (2.26 + 13.56) MHz, (2.26 + 27.12) MHz, and (13.56 + 27.12) MHz. We also use a non-liner global model that consists of a description of the plasma bulk based on a fluid dynamic approach coupled to a separate model of the sheath. We use argon and cover a wide range of operating conditions. We find the choices of different ωLF and ωHF's result in substantial changes of the decoupling of the mean ion energy from the ion flux. We also observe that increasing ωHF decreases the DC self-bias at a fixed value of ωLF. The PSR effect and, therefore, the electron power deposition strongly depend on the high frequency source. The experimental results are consistent with the predictions of the non-linear global model which proves the usefulness of such a rather simplistic model to study of 2f CCP discharges.
Simulation of the beamline thermal measurements to derive particle beam parameters in the ITER neutral beam test facility
Authors: Dalla Palma M. , Sartori E. , Zaupa M. , Pasqualotto R.
Published: July 2018

Injection of high energy neutral beam particles will be used in the ITER experiment for plasma heating and current drive. In a ITER heating beam injector, a 40 MW electrostatically accelerated negative beam will be neutralised and filtered along the beamline, obtaining a nominal 16.5 MW neutral beam power to be injected in the tokamak plasma or intercepted during conditioning and commissioning. The beam will heat the actively cooled panels of the beamline components with up to 13 MW/m2 surface power density and 18 MW power. These extreme conditions require testing in a ITER full scale neutral beam test facility under construction in Padova where the temperature of the beamline components will be monitored by 610 embedded thermocouples for protection against critical conditions, for recognising beam conditioning, and for deriving beam parameters. Power density maps of the expected beam-component interactions are applied on a parametric non-linear finite element model to simulate fields of expected temperatures. Such thermal maps are analyzed to derive the beam parameters during operation: divergence of 3-7 mrad and misalignment of 0-3 mrad. The sensibility of the temperature measurements is discussed considering a minimum 10% fraction of the nominal beam power.
Reorientation kinetics of hydroxyl groups in anatase TiO2
Authors: Chaplygin I. , Herklotz F. , Lavrov E. V.
Published: July 2018

The reorientation kinetics of hydrogen in a variety of complexes in the anatase polymorph of TiO2 was investigated by means of stress-induced dichroism. For the hydrogen-defect resulting in an O-H vibrational mode with a frequency of 3389 cm−1, the energy barrier separating adjacent equivalent in-plane sites of hydrogen was determined to be independent of the isotope and equal to 0.74 ± 0.02 eV, whereas the attempt frequency was found to be (1.10 ± 0.20) × 1012 and (0.75 ± 0.15) × 1012 s−1 for hydrogen and deuterium, respectively. The defect with vibrational modes at 3412 and 3417 cm−1 previously assigned to isolated hydrogen did not reveal alignment under the stress up to room temperature, which indicates that the barrier of hydrogen motion is above 0.9 eV.
Continuous roll-to-roll fabrication of organic photovoltaic cells via interconnected high-vacuum and low-pressure organic vapor phase deposition systems
Authors: Qu Boning , Forrest Stephen R.
Published: July 2018

We demonstrate continuous roll-to-roll (R2R) fabrication of single junction and tandem organic photovoltaic (OPV) cells on flexible plastic substrates employing a system that integrates organic deposition by high vacuum thermal evaporation (VTE) and low pressure organic vapor phase deposition (OVPD). By moving the substrate from chamber to chamber and then depositing films on stationary substrates, we achieve power conversion efficiencies of PCE = 8.6 ± 0.3% and 8.9 ± 0.2% for the single junction and tandem cells, respectively. Single junction OPVs are also fabricated on a continuously translating substrate at 0.3 cm/s, to achieve PCE = 8.5 ± 0.2%. Thin films grown on translating substrates by OVPD show <3% thickness non-uniformity and 0.66 nm root mean square surface roughness, similar to that obtained by VTE. Our results suggest that R2R film deposition comprising multiple vapor deposition technologies is a promising method for rapid speed and continuous manufacturing of high quality, small molecular weight organic electronic materials.
Probing directionality of local electronic structure by momentum-selected STEM-EELS
Authors: Yamaguchi A. , Haruta M. , Nemoto T. , Kurata H.
Published: July 2018

Electron energy-loss spectroscopy (EELS) using a scanning transmission electron microscope (STEM) provides information on the local electronic structure around an atomic column irradiated by the incident electron probe. In this study, we present a method for detecting the directionality of chemical bonds with atomic resolution by selecting a specific atomic column and the direction of momentum transfer with an off-axis collection aperture in the STEM-EELS measurement. It is shown that the oxygen K-edge fine structures in SrTiO3 measured from the crystallographically equivalent oxygen sites, which are in TiO-planes perpendicular to the electron probe direction, show different structures depending on the directionality of the σ-bond between the oxygen and titanium atoms. This method opens up a way to explore the electronic states in anisotropic materials and interfaces with atomic resolution.
Peptide model systems: Correlation between thermophilicity and hydrophilicity
Authors: Niether Doreen , Kriegs Hartmut , Dhont Jan K. G. , Wiegand Simone
Published: July 2018

In recent years, the response of biomolecules to a temperature gradient has been utilized to monitor reactions of biomolecules, but the underlying mechanism is not well understood due to the complexity of the multicomponent system. To identify some underlying principles, we investigate the thermal diffusion of small amide molecules in water systematically. We re-analyze previous measurements of urea and formamide and compare the results with acetamide, N-methylformamide, and N,N-dimethylformamide, amides with a lower hydrophilicity. It turns out that less hydrophilic substances do not show the typical temperature dependence of water soluble macromolecules. Analyzing temperature and concentration dependent measurements using an empirical expression originally derived for nonpolar mixtures, we find that the so-called isotope contribution depends strongly on the hydrophilicity of the solute. This can be qualitatively understood by comparing with molecular dynamic simulations of Lennard-Jones fluids. The hydrophobic/hydrophilic balance also influences the structure in the fluid and with that the thermal expansion coefficient, which correlates with the thermal diffusion coefficient. Furthermore, we observe a clear correlation of the temperature and concentration dependence of the Soret coefficient with the hydrophilicity, which can be quantitatively described by the partition coefficient log P.
Comparison of the spin-transfer torque mechanisms in a three-terminal spin-torque oscillator
Authors: Jué Emilie , Rippard William H. , Pufall Matthew R.
Published: July 2018

We have studied magnetization dynamics in three-terminal spin-torque oscillators (STOs) and present a direct method to compare the efficiencies of exciting oscillations in STOs through two mechanisms of spin transfer torque: the spin filtering torque (SFT) and the spin-orbit torque (SOT). The devices are composed of spin-valves patterned on a Pt wire that can be excited by a SFT and/or a SOT, depending on the pathway of the DC current. By varying the device and wire size, we tune and compare the efficiencies of both mechanisms in terms of current and current density. To a first approximation, for sufficiently narrow Pt wires (compared to the dimension of the spin-valve), significantly more current is required to excite the devices with SFT than with SOT, whereas in terms of current density, the SFT is up to three times more efficient than the SOT in the system studied. We investigate the limits of this comparison using control samples where the spin-valve is replaced by a magnetic tunnel junction (MTJ) or where the Pt wire is replaced by a Cu wire. A three terminal STO made with a MTJ is the most appropriate device to compare the efficiencies of both spin transfer mechanisms in order to avoid additional spin transfer torque induced by current shunted through the magnetic pillar.
Compensation and hydrogen passivation of magnesium acceptors in β-Ga2O3
Authors: Ritter Jacob R. , Huso Jesse , Dickens Peter T. , Varley Joel B. , Lynn Kelvin G. , McCluskey Matthew D.
Published: July 2018

Magnesium-doped gallium oxide may be utilized as a semi-insulating material for future generations of power devices. Spectroscopy and hybrid functional calculations were used to investigate defect levels in Czochralski-grown β-Ga2O3. Substitutional Mg dopants act as deep acceptors, while substitutional Ir impurities are deep donors. Hydrogen-annealed Ga2O3:Mg shows an IR peak at 3492 cm−1, assigned to an O-H bond-stretching mode of a neutral MgH complex. Despite compensation by Ir and Si and hydrogen passivation, high concentrations of Mg (1019 cm−3) can push the Fermi level to mid-gap or lower.
Canonical scattering coefficients upward recursion algorithm for multilayered sphere or long cylinder with large size parameters
Authors: Shiloah Nir
Published: July 2018

Calculation of the scattering coefficients appearing in Mie theory involves recursive relations for Bessel or Riccati-Bessel functions. Canonical recommendations prescribe using both upward and downward recursions for different types of functions. This makes the computational algorithm rather cumbersome. We have justified here the procedure using the upward recursions only, whose results are as stable as the canonical recommendations.
Numerical investigation on the interaction of planar shock wave with an initial ellipsoidal bubble in liquid medium
Authors: Xiang Gaoming , Wang Bing
Published: July 2018

This paper performs numerical investigations on the interaction of shock wave with an ellipsoidal bubble in liquid medium. The governing equations, including the conservative Euler equations and the non-conservative transport equation of the liquid volume fraction, are discretized based on the finite volume method. A tangent of hyperbola for interface capturing (THINC) interface reconstruction scheme is employed for the phasic densities and the liquid volume fraction to maintain the interface sharpness. The major-axis (z-axis) of the bubble is parallel to the incident planar shock wave. Different collapse behaviors are observed for two ellipsoidal geometries, named as the disk-like bubble and rugby-like one. Different collapse patterns of an initial ellipsoidal bubble are presented and the manifestation is that the transverse jets pierce the bubble differently, classified as along the centerline, off-centerline along the circumferential direction or along the meridian line if the aspect ratio is varied. For the disk-like bubble, it presents the strongest collapsing process under certain eccentricity, characterized by the highest water hammer pressure under the same incident shock strength. The second sheeting jet is an important factor that leads to the collapse of the remaining bubbles pierced by the first transverse jet.
Roll-to-roll processing system for transparent organic solar cells designed and verified
Authors: DeJarnette Drew
Published: July 2018

Combination of two fabrication processes into continuous roll-to-roll manufacturing for organic solar cells is developed for both single junction and tandem cells compatible with a variety of molecules.