Setting up a PDPA system for measurements in a Diesel spray

Abstract. A PDPA system was set up, optimised and used to measure the time resolved characteristics of the droplets inside a spray produced by a common-rail diesel fuel injection system. Some preliminary tests are performed with gas flows to optimise the optical set-up. Parametric studies are performed to gain an understanding of the particle density limits of the system, and their dependence on PDPA system parameters. Then the diesel spray produced by a single-hole injector is measured, with the fuel pressure ranging from 500 to 1300 bar, gas density in the test chamber ranging from ambient conditions to 40 kg/m3. Fuel and gas temperature were 25ºC. Beam waist size is reduced to the minimum value allowed by the optical stand-off of the spray enclosure. Receiver lens focal length is similarly reduced. Receiver slit width, which is found to have a dramatic effect on the detection of droplets during the injection period, was tested in the range from 100um to 25um. Tests performed with two different slit heights are tested, respectively 1mm and 50 μm, show that this parameter has minimal effect on performance. PMT voltage (gain) is held to a moderately low value between 400 and 500 volt and the laser power between 400 and 800 mW in the green line. Optimum burst threshold is found to obtain the best quality data regardless of background level, which varies greatly in high-density pulsed sprays

Study of the Mg-Nd alloy obtained by electrolysis in molten oxifluoride media

Mg-Nd alloys have been produced by electrolysis of the molten mixture LiF-NdF3-MgF2 using Nd2(CO3)3 and MgF2 as raw materials. An electrolysis cell was designed having the anode made of super dense graphite and the cathode made of molybdenum metal. The quasi-binary system (NdF3-LiF)eutectic-MgF2 was investigated and the liquidus line was determined using thermo-differential analysis. The solubility of Nd2(CO3)3 in the LiF-NdF3-MgF2 system was investigated by the carbothermal technique

Elektrokemijski postupak za proizvodnju titanovih kompozitnih slitina

The paper presents a new method for precursors’ synthesis of titanium alloys matrix composites through an electrochemical process in molten calcium chloride. The cathode of the cell was made from metallic oxides powders and reinforcement ceramic particles, which were pressed and sintered into disk form and the anode from graphite. The process occurred at 850 °C, in two stages, at 2,7 / 3,2 V: the ionization of the oxygen in oxides and the reduction with calcium formed by electrolysis of calcium oxide fed in the electrolyte. The obtained composite precursors, in a form of metallic sponge, were consolidated by pressing and sintering. Chemical and structural analyses on composites samples were performed.Članak prikazuje novu metodu prethodne sinteze titanovih kompozitnih slitina s elektrokemijskim postupkom u rastaljenom kalcijevom kloridu. Katoda ćelije ustrojena je od praškastog metalnog oksida ojačan keramičkim česticama, koji je stlačen u obliku diska, a anoda je od grafita. Postupak se odvijao na 850 °C u dva stupnja, 2,7/3,2 V: ionizacija kisika u oksidima i redukcija kalcijem nastajala je elektrolizom kalcijevih oksida u elektrolitu. Dobiveni prethodno kompozit u obliku metalne spužve je očvrsnut tlačenjem i sinteriranjem. Provedena je kemijska i strukturna analiza uzoraka kompozita

Supervolcanoes Within an Ancient Volcanic Province in Arabia Terra, Mars

Several irregularly shaped craters located within Arabia Terra, Mars represent a new type of highland volcanic construct and together constitute a previously unrecognized martian igneous province. Similar to terrestrial supervolcanoes, these low-relief paterae display a range of geomorphic features related to structural collapse, effusive volcanism, and explosive eruptions. Extruded lavas contributed to the formation of enigmatic highland ridged plains in Arabia Terra. Outgassed sulfur and erupted fine-grained pyroclastics from these calderas likely fed the formation of altered, layered sedimentary rocks and fretted terrain found throughout the equatorial region. Discovery of a new type of volcanic construct in the Arabia volcanic province fundamentally changes the picture of ancient volcanism and climate evolution on Mars. Other eroded topographic basins in the ancient Martian highlands that have been dismissed as degraded impact craters should be reconsidered as possible volcanic constructs formed in an early phase of widespread, disseminated magmatism on Mars

Complex type 4 structure changing dynamics of digital agents: Nash equilibria of a game with arms race in innovations

The new digital economy has renewed interest in how digital agents can innovate. This follows the legacy of John von Neumann dynamical systems theory on complex biological systems as computation. The Gödel-Turing-Post (GTP) logic is shown to be necessary to generate innovation based structure changing Type 4 dynamics of the Wolfram-Chomsky schema. Two syntactic procedures of GTP logic permit digital agents to exit from listable sets of digital technologies to produce novelty and surprises. The first is meta-analyses or offline simulations. The second is a fixed point with a two place encoding of negation or opposition, referred to as the Gödel sentence. It is postulated that in phenomena ranging from the genome to human proteanism, the Gödel sentence is a ubiquitous syntactic construction without which escape from hostile agents qua the Liar is impossible and digital agents become entrained within fixed repertoires. The only recursive best response function of a 2-person adversarial game that can implement strategic innovation in lock-step formation of an arms race is the productive function of the Emil Post [58] set theoretic proof of the Gödel incompleteness result. This overturns the view of game theorists that surprise and innovation cannot be a Nash equilibrium of a game

Velocity-space sensitivity of the time-of-flight neutron spectrometer at JET

The velocity-space sensitivities of fast-ion diagnostics are often described by so-called weight functions. Recently, we formulated weight functions showing the velocity-space sensitivity of the often dominant beam-target part of neutron energy spectra. These weight functions for neutron emission spectrometry (NES) are independent of the particular NES diagnostic. Here we apply these NES weight functions to the time-of-flight spectrometer TOFOR at JET. By taking the instrumental response function of TOFOR into account, we calculate time-of-flight NES weight functions that enable us to directly determine the velocity-space sensitivity of a given part of a measured time-of-flight spectrum from TOFOR

On the mechanisms governing gas penetration into a tokamak plasma during a massive gas injection

A new 1D radial fluid code, IMAGINE, is used to simulate the penetration of gas into a tokamak plasma during a massive gas injection (MGI). The main result is that the gas is in general strongly braked as it reaches the plasma, due to mechanisms related to charge exchange and (to a smaller extent) recombination. As a result, only a fraction of the gas penetrates into the plasma. Also, a shock wave is created in the gas which propagates away from the plasma, braking and compressing the incoming gas. Simulation results are quantitatively consistent, at least in terms of orders of magnitude, with experimental data for a D 2 MGI into a JET Ohmic plasma. Simulations of MGI into the background plasma surrounding a runaway electron beam show that if the background electron density is too high, the gas may not penetrate, suggesting a possible explanation for the recent results of Reux et al in JET (2015 Nucl. Fusion 55 093013)

Modelling of the effect of ELMs on fuel retention at the bulk W divertor of JET

Effect of ELMs on fuel retention at the bulk W target of JET ITER-Like Wall was studied with multi-scale calculations. Plasma input parameters were taken from ELMy H-mode plasma experiment. The energetic intra-ELM fuel particles get implanted and create near-surface defects up to depths of few tens of nm, which act as the main fuel trapping sites during ELMs. Clustering of implantation-induced vacancies were found to take place. The incoming flux of inter-ELM plasma particles increases the different filling levels of trapped fuel in defects. The temperature increase of the W target during the pulse increases the fuel detrapping rate. The inter-ELM fuel particle flux refills the partially emptied trapping sites and fills new sites. This leads to a competing effect on the retention and release rates of the implanted particles. At high temperatures the main retention appeared in larger vacancy clusters due to increased clustering rate

Синдром хронической сердечной недостаточности вторичной Тетраде Фалло: клинические и диагностические аспекты на основе одного случая

Department of Pediatrics, Nicolae Testemitanu State Medical and Pharmaceutical University, Congresul III al Medicilor de Familie din Republica Moldova, 17–18 mai, 2012, Chişinău, Republica Moldova, Conferinţa Naţională „Maladii bronhoobstructive la copii”, consacrată profesorului universitar, doctor habilitat Victor Gheţeul, 27 aprilie, Chişinău, Republica MoldovaThe authors present a clinical case of a 17 year old boy, which in his clinical and paraclinical data highlighted the following diagnostic: Congenital heart failure; Tetralogy of Fallot; AV Block gr. III; Mitral valve insufficiency gr. IV; Tricuspid valve insufficiency gr. IV; Heart failure NYHA functional class gr. III-IV. The case focuses on complications that may occur in late cardio surgeries and the development of AV block gr. III disorders. If complications arose during the evolution of the disease, there would have been performed multiple pacemaker reimplantations. The article insists on the way how cardiovascular complications start as much as on the importance of prompt medical supervision to ensure the patient’s quality of life.В данной статье описан клинический случай ребёнка в возрасте 17 лет, у которого по клинико-инструментальным данным был установлен клинический диагноз – врожденный порок сердца, Tетрада Фалло, aтриовентрикулярная блокада III-ей степени. Имплантация исскуственного кардиостимулятора ритма сердца (1998, 2002, 2007). Недостаточность митрального клапана IV-ой степени. Недостаточность трикуспидального клапана IV-ой степени. НК IV NYHA

Escaping alpha-particle monitor for burning plasmas

This paper presents a diagnostic system, gamma-ray alpha-particle monitor (GRAM), for continuous monitoring of deuterium-tritium fusion alpha-particles in the MeV energy range escaped from the plasma to the first wall. The diagnostic is based on the detection of gamma-rays produced in nuclear reactions. The reactions Be-9(alpha,eta,gamma)C-12 and B-10(alpha,p,gamma)C-13 have been selected. For that purpose, Be- or B-10-target is placed on the first wall, where the alphas are expected to be mostly lost. Striking the target, the lost alphas generate specific gamma-rays, if their energy E-alpha > 1.5 MeV. To measure this gamma-ray emission, the target should be in the field of view of a collimated detector, which is protected from neutrons and background gammas. The calibrated detector could deliver absolute values of the lost alpha-particle flux with a temporal resolution depending on intensity of losses. A high-performance gamma-ray spectrometer with a novel architecture, GRITER, is proposed to be used in GRAM. It consists of a stack of the optically isolated high-Z fast scintillators with independent signal readout. GRITER is supposed to be operated at count-rates substantially exceeding the capability of a single crystal detector of the same size. The GRAM diagnostic system consists of two identical spectrometers, which measure both gamma-rays due to alpha-particle loss and gamma-ray background ensuring reliable data in a harsh reactor environment. GRAM could be tested during the non-DT plasma operation monitoring lost DD fusion products, neutral beam heating D-ions (E-D > 0.5 MeV) and ICRF accelerated H- and He-3-ions through the detection of gamma-rays resulting from nuclear reactions. The use of GRAM on JET and ITER, including events with extremely high loss rates, is discussed