bluuebunny/crossref_metadata_2025 huggingface dataset:
Sowing maize as a rotation crop in irrigated cotton cropping systems in a Vertosol: effects on soil properties, greenhouse gas emissions, black root rot incidence, cotton lint yield and fibre quality
Authors: Hulugalle N. R. , Nachimuthu G. , Kirkby K. , Lonergan P. , Heimoana V. , Watkins M. D. , Finlay L. A.
Published: December 2019

Although sowing winter cereal crops in rotation with irrigated cotton (Gossypium hirsutum L.) is practised by many Australian cotton growers, summer cereals such as maize (Zea mays L.) are sown more frequently than previously. Our objective was to quantify the impact of sowing maize rotation crops on soil properties, greenhouse gas emissions, incidence of black root rot (BRR) disease and crop yields in an ongoing long-term experiment located in a Vertosol in north-western New South Wales. The historical treatments were cotton monoculture (sown after either conventional or minimum tillage) and a minimum-tilled cotton–wheat (Triticum aestivum L.) rotation. The experiment was redesigned in 2011 by splitting all plots and sowing either maize during summer following the previous year’s cotton or retaining the historical cropping system as a control. pH and exchangeable cation concentrations were highest, and electrical conductivity (EC1:5) lowest during 2012, the season following a flood event, but were unaffected by sowing maize. In subsequent seasons, with the onset of dry conditions, pH and cation concentrations decreased, and EC1:5 increased. The upper horizons (0–0.3 m) of plots where maize was sown had higher concentrations of exchangeable Ca and Mg during 2012, and 0.45–1.20 m had higher concentrations of exchangeable Na and exchangeable sodium percentage, but these differences disappeared in subsequent years. Soil organic carbon (SOC) in the surface 0.15 m was higher with maize, with differences becoming evident three years after maize was first sown but without any increases in SOC storage. Soil under maize was less resilient to structural degradation. BRR incidence was lower in maize-sown plots only during 2012. Stepwise linear regression suggested that high concentrations of exchangeable Ca and Mg in the surface 0.15 m played a role in reducing BRR incidence during 2012. Maize rotation introduced into cotton monocultures improved lint yields and reduced greenhouse gas emissions but had little impact in a minimum-tilled cotton–wheat rotation. Maize is a suitable rotation crop for irrigated cotton in a two-crop sequence but is of little advantage in a cotton–wheat–maize sequence.
Beach safety: can drones provide a platform for sighting sharks?
Authors: Butcher Paul A. , Piddocke Toby P. , Colefax Andrew P. , Hoade Brent , Peddemors Victor M. , Borg Lauren , Cullis Brian R.
Published: December 2019

Abstract ContextA series of unprovoked shark attacks on New South Wales (Australia) beaches between 2013 and 2015 triggered an investigation of new and emerging technologies for protecting bathers. Traditionally, bather protection has included several methods for shark capture, detection and/or deterrence but has often relied on environmentally damaging techniques. Heightened environmental awareness, including the important role of sharks in the marine ecosystem, demands new techniques for protection from shark attack. Recent advances in drone-related technologies have enabled the possibility of real-time shark detection and alerting. AimTo determine the reliability of drones to detect shark analogues in the water across a range of environmental conditions experienced on New South Wales beaches. MethodsA standard multirotor drone (DJI Inspire 1) was used to detect shark analogues as a proxy during flights at 0900, 1200 and 1500 hours over a 3-week period. The 27 flights encompassed a range of environmental conditions, including wind speed (2–30.0kmh−1), turbidity (0.4–6.4m), cloud cover (0–100%), glare (0–100%), seas (0.4–1.4m), swells (1.4–2.5m) and sea state (Beaufort Scale 1–5 Bf). Key resultsDetection rates of the shark analogues over the 27 flights were significantly higher for the independent observer conducting post-flight video analysis (50%) than for the drone pilot (38%) (Wald P=0.04). Water depth and turbidity significantly impaired detection of analogues (Wald P=0.04). Specifically, at a set depth of 2m below the water surface, very few analogues were seen by the observer or pilot when water turbidity reduced visibility to less than 1.5m. Similarly, when water visibility was greater than 1.5m, the detection rate was negatively related to water depth. Conclusions The present study demonstrates that drones can fly under most environmental conditions and would be a cost-effective bather protection tool for a range of user groups. ImplicationsThe most effective use of drones would occur during light winds and in shallow clear water. Although poor water visibility may restrict detection, sharks spend large amounts of time near the surface, therefore providing a practical tool for detection in most conditions.
Characterization of the activity, aggregation, and toxicity of heterodimers of WT and ALS-associated mutant Sod1
Authors: Brasil Aline de Araújo , de Carvalho Mariana Dias Castela , Gerhardt Ellen , Queiroz Daniela Dias , Pereira Marcos Dias , Outeiro Tiago Fleming , Eleutherio Elis Cristina Araujo
Published: December 2019

Significance

Aggregation of the antioxidant enzyme Sod1 represents common factors of both familial (fALS) and sporadic cases of ALS, a fatal neurodegenerative disease. Although many ALS studies have focused on Sod1 homodimers/homomers, the investigation of Sod1 heterodimers/heteromers remains controversial and has mostly been performed with recombinant proteins in vitro, in the absence of a cellular environment. By using living cells, this study sheds light into a critical issue in the context of fALS, the high toxicity of the WT–mutant heteromeric inclusions, especially WT–A4V heteromers which accumulate both in human cells as well as in chronologically aged yeast cells. Besides the aggregation, we proposed that an inefficient heteromer response against oxidative conditions might contribute to fALS-linked mutant hSod1 toxicity.
Development of an autonomous and bifunctional quorum-sensing circuit for metabolic flux control in engineered
Escherichia coli
Authors: Dinh Christina V. , Prather Kristala L. J.
Published: December 2019

Significance

Efficient microbial synthesis in challenging pathways relies on dynamic regulation of multiple metabolic fluxes to balance several competing goals. To address these situations, we developed an autonomous, pathway-independent, and layered regulation tool. By incorporating parts from 2 different quorum-sensing systems, the layers of our system can be tuned independently to ensure generalizability. Application of the regulation system to overcoming 2 different sets of challenges in the naringenin and salicylic acid pathways resulted in significant improvements in titer, demonstrating that the system is an effective tool for improving pathway production.
Divergent trophic responses of sympatric penguin species to historic anthropogenic exploitation and recent climate change
Authors: McMahon Kelton W. , Michelson Chantel I. , Hart Tom , McCarthy Matthew D. , Patterson William P. , Polito Michael J.
Published: December 2019

Significance

We reveal species-specific changes in penguin trophic responses to historic shifts in krill availability over the last century by applying new molecular isotope techniques to historic penguin museum specimens. Generalist foraging gentoo penguins, whose population increased 6-fold in the last 40 y, showed adaptive shifts in trophic position in concert with changes in Antarctic krill availability following historic exploitation of marine mammals and recent climate change. In contrast, chinstrap penguins maintained a consistent krill diet despite changes in krill availability and concurrent population declines. These results highlight how responses to shared environmental change can vary substantially among closely related species, supporting ecological niche theory that specialists will be more sensitive to environmental change than their generalist counterparts.
Corpora amylaceaact as containers that remove waste products from the brain
Authors: Riba Marta , Augé Elisabet , Campo-Sabariz Joan , Moral-Anter David , Molina-Porcel Laura , Ximelis Teresa , Ferrer Ruth , Martín-Venegas Raquel , Pelegrí Carme , Vilaplana Jordi
Published: December 2019

Significance

Aging and neurodegenerative processes induce the formation of waste substances in the brain. Some of these substances accumulate incorpora amylacea(CA). We reveal that CA are released from the brain into the cerebrospinal fluid and are present in the cervical lymph nodes, into which cerebrospinal fluid drains through the meningeal lymphatic system. We also show that CA can be phagocytosed by macrophages. We conclude that CA can act as waste containers and hypothesize that CA are involved in a mechanism that cleans the brain. We also postulate that CA may contain clinical markers of brain disorders and may also play significant roles in some brain autoimmune diseases. These last points merit further study due to their possible clinical implications.
Explicit teaching of segmentals versus suprasegmentals in developing speaking skills by interpreter trainees
Authors: Yenkimaleki Mahmood
Published: December 2019

The present study investigates the effect of explicit teaching of segmentals and suprasegmentals in developing speaking skills for Farsi-English interpreter trainees. Three groups of student interpreters were formed. All were native speakers of Farsi who studied English translation and interpreting at the BA level at the University of Applied Sciences in Tehran, Iran. Participants were assigned to groups at random, but with equal division between genders (7 female and 7 male students in each group). No significant differences in English language skills (TOEFL scores) could be established between the groups prior to the experiment. Participants took a pretest of speaking skills before starting the program. The control group listened to authentic audio tracks in English and discussed their contents, watched authentic English movies, and discussed issues in the movies in pairs in the classroom. The first experimental group spent part of the time on theoretical explanation of, and practical exercises with, English suprasegmentals. The second experimental group spent part of the time on theoretical explanation of, and practical exercises with, English segmentals. The total instruction time was the same for all three groups, i.e. 12 hours. Students then took a posttest in speaking skills. The results show that the explicit teaching of suprasegmentals significantly improved the students’ speaking skills more than that of the other groups. These results have pedagogical implications for curriculum designers, interpreting programs for training future interpreters, material producers and all who are involved in language study and pedagogy.
La place de la Francophonie et de l’interprétation coréen-français en Corée du Sud
Authors: Choi Jungwha S. H.
Published: December 2019

Avec l’adhésion de la Corée du Sud à l’Organisation internationale de la Francophonie (OIF) et l’organisation des
Jeux Olympiques d’hiver de 2018 à Pyeongchang, en Corée du Sud, la francophonie suscite un intérêt croissant. Une enquête a été
menée auprès d’interprètes de conférence exerçant avec un français actif afin d’évaluer la situation actuelle du marché de
l’interprétation coréen-français, ainsi que ses perspectives d’avenir. L’essor actuel de la demande survivra-t-il à l’effet Jeux
Olympiques ?
Response surface methodology: critical parameters on the production of mangrove wood biochar yield
Authors: Ghafar H , Zailani R , Yaakob Y , So’aib M S
Published: December 2019

The infiltration of oxygen is unfavorable since it burned away the biomass. Other parameters were also contributed to the production of biochar. The experiments on mangrove wood were conducted using a fixed bed pyrolysis reactor with the temperature range of 300°C to 600°C, oxygen range from 0% to 10% and holding time from 2 hours to 4.4 hours. Response surface methodology (RSM) was implanted for process optimization. There were a significant effect of oxygen percentages and holding time on the production of biochar yield within the range of study. Results show that the optimum biochar yield of 15.2% when the pyrolysis temperature, oxygen percentage, and holding time were 402.5°C, 2.29% and 2 hours respectively. Confirmation experiment showed that 15.1% of biochar yield was obtained with the same pyrolysis parameters which validated the previous optimization.
A Study of Illumination Level at Public Transit Infrastructure in Butterworth, Penang.
Authors: Ainun Musir A , Rosli N F , Daim M S , Abdul Hamid M S , Dollah Z
Published: December 2019

Illumination level is an important thing in our daily life. Therefore, it is necessary for the building or any infrastructure to achieve the minimum recommendations of illumination. This case study was focus on the evaluation of illumination level at public transit infrastructure which is Pengkalan Sultan Abdul Halim Ferry Terminal. The aim of this study is to evaluate either the illumination level in selected area is comply to the standard of Panduan Teknik JKR or not. Field measurement was conducted, and the reading of lux meter were recorded. The illumination level of the selected location is in good condition during the day. The walkways area achieved 100% of recommendation standard followed by waiting area is about 85%. Only ticket counter in satisfactory level with 86.20% and only 13.80% achieved the minimum requirement. Only walkways achieved 65.4% of satisfactorily standard and 34.6% in bad condition for the night situations. The bad condition of illumination at ticket counter and waiting area during the night. The 100% of the area are in bad condition which is dangerous to the users. From the results, it is suggested to do routine maintenance to improve the illumination level and achieve the minimum requirement of standard.
Overview of integrated PVA-membrane with Zn-cyclen for CO2 separation
Authors: Husain S , Hamzah F
Published: December 2019

Carbon dioxide (CO2) is a greenhouse gas that produces from the combustion of fossil fuel. The consumption of fossil fuel in industrial activity has increased the concentration of CO2 emitted in the atmosphere. When the concentration of CO2 increases, the more heat are released. Thus, creating the global warming issue and climate change to the world. This climate change and global warming issue have attract the attention of worldwide. There are lot of carbon capture techniques proposed to overcome these problems. However, most of it are costly, and need a long dissociation and CO2 separation process. Therefore, innovative technique and process optimization are needed in order to improve the process efficiency of this technology. The most common techniques used in this technology are cryogenic, biological technique, and membrane technique. Membrane technique with a biological approach has promising high CO2 separation performance. This mimic enzyme based membrane has several advantages such as low cost, simple production procedure and high CO2 separation performance. From the review, the use of PVA membrane integrated with mimic enzyme could be work together towards the improvement of carbon capture technology. This review provides the information and potential of an alternative approach of carbon capture technology to reduce the amount of CO2 emitted from the fossil fuel industry.
Study on the viability of egg shell as a lost circulation material in synthetic based drilling fluid
Authors: Nik Ab Lah N K I , Ngah K , Sauki A
Published: December 2019

Lost circulation is one of the most severe issues in drilling operation which can cause fracture formation or be induced during drilling activities. These scenarios make it imperative to design the drilling fluid in a minimal invasion of the fluid that occur in the formation along with assist in strengthening the wellbore condition. To solve this problem, Lost Circulation Materials (LCM) are required which is expected to bridge and seal the fractures. As the contemporary worldwide development towards environment friendly, technical ability and cost-effectiveness, hence the viability of Egg Shells as LCM are being investigated since the daily disposal waste is rich in Calcium Carbonate (CaCO3) compound. In addition, the effect of egg shell particle size distribution on the drilling fluid performance was also study. The performance of egg shells was compared with the industry standard-sized CaCO3 in term of its rheology properties, fluid loss, fluid invasion, and lubrication ability. The rheology properties result shows a stable reading while for High Pressure High Temperature (HPHT) filter press test, the drilling fluids performance showed the same mud cake thickness of 1/32 but slightly different in fluid loss. The drilling fluids also has a minimal invasion on Sand Bed Test (SBT) with lubrications coefficient of 0.0753. From this study, it is found that egg shells can function effectively as LCM additives, the same as the standard CaCO3 used in the industry.
Governing characteristics of heat transfer in separated channel flows
Authors: Davletshin I A , Mikheev N I , Shakirov R R , Paereliy A A
Published: December 2019

Heat transfer in the separation region behind a rib has been studied experimentally in different regimes of air flow. Heat transfer characteristics have been considered in a wide range of geometrical dimensions of the rib and the channel. Distributions of heat transfer coefficients have been obtained. They were employed for estimation of the position and values of maximum heat transfer coefficients in the separation region. The data were analyzed in order to obtain an empirical equation.
DNS of starting turbulent jets with variable density
Authors: Ivashchenko V A , Mullyadzhanov R I
Published: December 2019

We study starting turbulent round jets with variable density using Direct numerical simulations (DNS). A fully developed turbulent air flow at constant Reynolds number Re = 5300 is injected to space, filled with air, carbon dioxide or helium with a small co-flow, with variable density being due to the mixing of different gases. We compare the celerity factor, centreline velocity and dynamics of the vortex dipole in front of the jet between all the considered cases.
Dynamic and thermal interference effects on two neighbouring building models
Authors: Korobkov S V , Terekhov V I , Koshin A A , Gnyrya A I , Mikhailov D A
Published: December 2019

The paper considers the dynamic and thermal interference effects on two neighbouring building models in the form of square prisms arranged at a short distance from each other. It is shown how relative positions of the models affect the specific phenomena caused by the airflow interactions.
Flow at the interface of two rotating fluids
Authors: Naumov I V , Sharifullin B R , Shtern V N
Published: December 2019

Recent studies discovered a discontinuity of the radial velocity (slip) at the interface of two immiscible rotating fluids. This work investigates how this phenomenon depends on densities and viscosities of fluids. A sealed vertical cylindrical container models a bioreactor. The rotating lid drives the flow while other container walls are stationary. As the rotation intensifies, the slip develops at the interface. A conjecture is that the slip occurs due to a difference in fluid densities and the centrifugal force. To test this conjecture, this experimental work uses fluids of close densities and reveals that the slip does not disappear even if the density difference is small, compared with that in prior studies. For comparison, this study also explores the case where the densities significantly differ while the fluid viscosities are close. The slip occurs in this flow as well. A new conjecture is that competing effects of the upper-fluid rotation and convergence near the interface also can cause the slip. This study also shows that the slip is a robust phenomenon occurring in swirling flows of various fluids.
Transition to turbulence in confined flow over a cylinder with low aspect ratio
Authors: Palkin E , Mullyadzhanov R
Published: December 2019

We report on Large-eddy simulations (LES) of a flow around a cylinder in a narrow duct channel at the Reynolds number of 2 000, 3 000 based on the bulk velocity and diameter of the cylinder. We investigate a mechanism of the transition occurring from steady laminar flow at Re = 2 000 to turbulent flow at Re = 3 000 with attached recirculation zone and thin sinusoidal far wake.
Experimental investigation of the natural and controlled disturbance development in a supersonic boundary layer on the swept wing
Authors: Panina A V , Kosonov A D , Semenov N V , Yermolaev Yu G , Kolosov G L , Yatskikh A A
Published: December 2019

The results of investigation of the transverse flow inhomogeneity effect on the natural and controlled disturbance development in 3D supersonic boundary layer are considered. The transition curves were measured on a model of a smooth swept wing and on a swept wing with roughness elements of two configurations. The influence of periodic surface roughness on the growth of natural pulsations (without using a discharge) in the boundary layer is determined. In experiments with artificial disturbances it is found that the periodic modulation of mean flow can lead to stabilization of controlled disturbances in supersonic boundary layer on a swept wing. It was found out that the weak flow inhomogeneity can influence the effectiveness of the active/passive technology of supersonic boundary layer transition control, including the surface microroughness on a swept wing.
Stability of magnetohydrodynamic flow around a circular cylinder
Authors: Proskurin A V , Sagalakov A M
Published: December 2019

We consider the stability problem of the two-dimensional flow of an incompressible electroconducting viscous liquid near a circular cylinder in the presence of magnetic field. A Rvachev function method with the Chebyshev collocation is used for the stability analysis. We construct an approximate solution that satisfies all boundary conditions exactly. The results coincide well with the reference data without the magnetic field. The method is simpler than the widely used spectral/hp element method, in particular, because it does not require mesh generation, and the collocation algorithm does not handle the boundary conditions or any geometric information.
Study of aerodynamics of the jet spreading over cylindrical surface
Authors: Seydulla Zh K , Isataev M S , Toleuov G K
Published: December 2019

The purpose of this work is to study the fields of average values of velocity in a turbulent air jet propagating along a smooth cylindrical surface with an adjustable nozzle width being b, the curvature parameter SR and Re number on both convex and concave surfaces. To identify basic patterns of physical phenomena occurring in the boundary layer, it has been established that in universal coordinates, the wall velocity profiles have a universal nature in the region of a change in the curvature parameter 0 ⩽ SR
⩽ |±0.12|, and virtually coincide with the velocity profiles of a turbulent boundary layer on a flat plate in a uniform flow past, except for the velocity peak region. This is due to the fact that the longitudinal pressure gradient is 104 ÷ 105 times lower than transverse pressure gradient. According to our data, it has been established that the excess static pressure near the streamlined surface with a distance from the nozzle and an increase in jet thickness can reach up to 30–40% of the velocity head.
The influence of the shape and the orientation angle of the tabs on heat transfer in a separated region behind a backward-facing step
Authors: Terekhov V I , Dyachenko A Yu , Zhdanov V L , Smulsky Ya J
Published: December 2019

The influence of the shape, location and inclination angle of the tabs on heat transfer in the separation region behind the backward-facing step at the Reynolds number Re = 4000 has been investigated. The used tabs were rectangular and triangular in shape and had the same height of 6 mm. Their transverse spacing and the angle of attack varied. The presence of tabs approached the area of the maximum heat transfer to the step, and at that rectangular tabs were more effective due to the increase in the cross-sectional area. The smallest and the largest angles of attack reduced the maximum heat transfer, and the greatest heat transfer was observed for tabs installed either perpendicular to the flow or at angle 110°.
Oxidative steam conversion of light alkanes
Authors: Dimov S V , Gasenko O A
Published: December 2019

Oxidative steam reforming of C2-C4 alkanes was studied in an annular catalytic reactor under atmospheric pressure over two catalysts. Concentrations of the products of chemical reactions in the outlet gas mixture were measured at different temperatures of reactor. Effects of temperature have been compared for different residence time for the inlet gas ratio water/air/C2-C4 alcanes of 7: 4.5:1.
Combustion of round hydrogen microjet in a cocurrent air flow with nanopowder
Authors: Kozlov V V , Grek G R , Litvinenko M V , Litvinenko Yu A , Tambovtsev A S , Shmakov A G
Published: December 2019

In the present paper we show our recent experimental data on diffusion combustion of a round hydrogen microjet in a cocurrent flow of air mixed with nanoparticles of TiO2. The hydrogen microjet is emanated from a round micronozzle which is surrounded by a coaxial slit to produce the cocurrent flow. Combustion events found in the present conditions are similar to those observed in the previous studies on diffusion combustion of hydrogen microjets at subsonic and supersonic velocities. In a subsonic range, the so-called “bottleneck-flame region” is generated close to the nozzle exit, while in high-speed conditions the flame separates from the nozzle. At increasing velocity of both the hydrogen microjet and the cocurrent flow, the “bottleneck-flame region” is still found and the combustion becomes more intense. The “bottleneck-flame region” is suppressed at the microjet velocity approaching transonic values.
Simulation of gas injection from a long tube into a liquid-filled pipe
Authors: Alekseev M V , Lobanov P D , Svetonosov A I , Lezhnin S I
Published: December 2019

The data on the evolution of the interface at the sudden injection of gas from a long tube into a liquid column was obtained. High speed video of experiments and calculations in OpenFoam software package were used as research methods. Investigations were performed for different initial pressures. Typical configurations of the interface for different time periods were shown both experimentally and numerically.
Calculation of probability density function of particle velocity in turbulent flow
Authors: Derevich I V , Klochkov A K
Published: December 2019

The random motion of inertial particles in uniform isotropic turbulence is considered. Fluctuations of the gas velocity at the particle trajectory are modelled as a random Gauss process with a finite decay time of the autocorrelation function. A closed equation for the probability density function (PDF) of the random particle velocity is derived. An analytical solution of the equation for the PDF is found. The equation for the PDF is solved by two numerical methods. The first method of solution is based on the finite-difference approximation of the equation for the PDF. The second method is based on the calculation of empirical PDF, which is obtained by averaging over an ensemble of random trajectories of particles. The results of the comparison of analytical numerical solutions are presented.
Motion characteristics of bubbles behind a sudden channel expansion
Authors: Chinak A V , Evdokimenko I A , Kulikov D V , Lobanov P D
Published: December 2019

Characteristics of movement of gas bubbles behind a sudden channel expansion were studied experimentally. The data on the distribution of the gas phase and speed of movement of bubbles were obtained. It is shown that at a distance from the sudden channel expansion the bubbles slow down, which relates to the slowing down of liquid due to an increase in the flow cross section. After the reattachment point, the bubbles move along a more curved path than upstream. It is shown that bubble clusters can form in the flow recovery zone. The velocity distribution in the channel was studied by means of laser Doppler anemometry (LDA).
Peculiarities of gas bubble growth in magmatic melt under the condition of rapid decompression
Authors: Chernov A A , Pil’nik A A , Davydov M N
Published: December 2019

The growth mechanism of a single gas bubble in a highly viscous volatile-saturated magmatic melt during its rapid decompression is investigated. A new analytical solution of the problem is shown. It correctly describes the bubble growth dynamics in a wide range of supersaturations achieved as a result of decompression and at all stages of the process including the transitional one. Accounting for this stage is extremely important if we consider highly-viscous magmatic melts. It is shown that after some time bubble growth is determined solely by diffusion, and the process has a self-similar character.
The effect of the initial salt concentration on the rate of crystallization in a thin layer of solution
Authors: Morozov V S
Published: December 2019

When simulating crystallization, it is necessary to take into account the temperature distribution on the solution interface, the place of emergence of the first crystalline center, as well as the rate of evaporation and crystallization. Depending on the specified parameters, three crystallization scenarios are implemented: 1) a sharp decrease in the crystallization rate J
cr with time, 2) an increase in J
cr with time, 3) an increase in J
cr and reaching the maximum, and then a decrease in the crystallization rate.
Analysis of the influence of mass transfer processes between reactor and containment on the operation of the WWER steam generator in condensation mode
Authors: Shlepkin A S , Morozov A V
Published: December 2019

This paper presents an analysis of mass transfer processes between the reactor and the containment of a WWER reactor in case of a loss of coolant accident (LOCA). The effect of the differential pressure arising due to the difference in the densities of the media in the primary circuit and in the containment on mass transfer is considered. A description of the HA-2M test facility used for the study of process between the containment and the reactor is given. The results of analysis of the experimental data are presented.
Investigation of aerodynamics of improved four-vortex furnace device
Authors: Alekseenko S V , Shadrin E Yu , Anufriev I S , Boyko E E
Published: December 2019

In this work, the inner aerodynamics of a perspective vortex furnace device with a four-vortex burner layout scheme is experimentally investigated. Using the contactless optical flow diagnostics method (PIV), the averaged velocity distributions are obtained in a number of cross sections of the furnace model for various modes. The spatial structure of the flow is studied. It is found that the flow consists of four vertical vortices with curved rotation axes.
Plasmon resonance in CVD graphene-silver nanoparticle composites
Authors: Boyko E V , Kostogrud I A
Published: December 2019

Investigation results on the morphology and optical properties of polymer-graphene composites with silver nanoparticles deposited by pulsed laser ablation are presented. Graphene was obtained by the CVD method and transferred to PET/EVA polymer through thermal pressing. It has been established that with an increase in the thickness of deposited silver film, a transition from bimodal distribution of particles to formation of elongated rectangular nanostructures is observed. A similar phenomenon can be explained by accumulation of deposited silver particles along the boundaries of adjacent graphene crystallites. It is experimentally shown that the degree of plasmon absorption depends strongly on the mass-average thickness of the deposited metal coating and size of nanoparticles. Deepening of the peak of plasmon absorption simultaneously with a general decrease in sample transparency occurs when the film thickness is changed up to 6 nm. A further increase in thickness does not affect the intensity of plasmon absorption and scattering, but leads to a general decrease in transparency of the polymer-graphene-silver composite. It is shown that the highest degree of radiation attenuation is in the wavelength range from 400 to 600 nm.
Simulations of the glow discharge positive column parameters in helium
Authors: Demin N A , Fedoseev A V
Published: December 2019

The self-consistent model for the positive column of a glow discharge is presented. The model is based on the simultaneous solution of the nonlocal Boltzmann equation for electron energy distribution function, continuity equation for ions and Poisson equation for electric field. Calculations were performed for a discharge tube similar to the Plasma Kristall-4 experiments for plasma forming gas helium for the range of pressures of 20-70 Pa and the range of discharge currents of 0.5-2.5 mA. Axial electric field strength, electron temperature and electron density dependences on the discharge current and the gas pressure are obtained. The results show a good correlation with the data obtained by the other authors.
Comparison of continual and molecular modeling of gas flow for diamond deposition
Authors: Gorbachev Yu E , Leshchev D V , Plotnikov M Yu , Rebrov A K , Yudin I B
Published: December 2019

For the purpose of simulation of diamond-growth processes, the comparison of reacting gas flows modelled in a heated cylindrical channel has been performed by two different approaches: DSMC method and solution of Navier-Stokes equations. The impact of the channel length on the degree of hydrogen and methane dissociation in the gas mixture has been analyzed. The obtained data were compared with the experimental data.
Gas molecules could be transferred through the lipid bilayer by kinks-solitons
Authors: Mokrushnikov P V
Published: December 2019

A hypothesis on the transfer of gas molecules through erythrocyte membrane by kink-solitons is discussed. Earlier it was supposed that gas molecules could be transferred through the lipid bilayer by kinks. It is accepted that kinks can emerge due to thermal vibrations. However, it remained unclear how the chaotic thermal vibrations can generate kinks moving along a hydrocarbon chain. According to the proposed hypothesis, kink-solitons appear under the simultaneous action of compressive lateral mechanical stresses and straining longitudinal mechanical stresses in the membrane. Compressive lateral stresses should have a certain value. This model explains a sharp increase in gas permeability of the membrane that occurs when erythrocyte passes through a microcapillary network, which is accompanied by substantially increased compressive lateral mechanical stresses.
Non-local character of negative glow emission of a low pressure glow discharge
Authors: Pinaev V A
Published: December 2019

A beam electron energy distribution function (BEEDF) in the cathode regions of a low-pressure glow discharge in helium was calculated using a Monte-Carlo technique. Based on the obtained data on the distribution of the BEEDF along the discharge length, the excitation rate of the 1s3p
1P level was calculated assuming that the direct electron excitation of helium atoms from the ground state takes place. It is shown that the calculated excitation rates of the 1s3p
1P level along discharge path are in good agreement with the experimentally measured emission distribution of the 501.6 nm helium spectral line.
Thermophysical properties of Inconel 718 alloy
Authors: Agazhanov A Sh , Samoshkin D A , Kozlovskii Yu M
Published: December 2019

The thermal diffusivity (a), linear thermal expansion coefficient (α), isobaric heat capacity (Cp
) and phase transition enthalpy (ΔH) of Inconel 718 superalloy were determined by laser flash method, dilatometric method and differential scanning calorimetry in the temperature range of 298–1375…1473 К. The thermal conductivity (λ) has been calculated from the measurement results. The estimated errors of the obtained data were 2–5%, 3–5%, 2–3% and (1.5–2)×10−7 K−1 for a, λ, Cp
and α, respectively. The approximation equations and a table of reference values for the studied properties have been obtained.
Molecular simulation of viscosity of nanofluids based on water with metal particles
Authors: Krasnolutskii S L , Belkin A A , Lezhnev E V
Published: December 2019

Shear viscosity coefficient of water-based nanofluids with copper particles is simulated with the molecular dynamics method. The interaction of water molecules with each other was modeled with Lennard-Jones potential. The viscosity coefficient was calculated on the basis of the fluctuation-dissipation theorem by the Green–Kubo formula. The selection of parameters of the potential corresponding to the experimental values of water viscosity and density at a given temperature of 25°C at the atmospheric pressure is performed. Rudyak–Krasnolutskii (RK) and Rudyak–Krasnolutskii–Ivanov (RKI) potentials described interaction between nanoparticles and water molecules and nanoparticles with each other, respectively. Diameters of copper nanoparticles used were 2 and 4 nm. Volume concentration of the nanoparticles varied from 1% to 5%. It is shown that the viscosity of the nanofluids exceeds significantly the viscosity of suspensions with macroscopic particles and increases with a decrease in the size of nanoparticles at a fixed volume concentration. The paper also presents the calculation data of pair distribution functions for pure water and nanofluid. It is shown that the water near the nanoparticle is much more structured than in the free volume. This large ordering in the nanofluids is one of the key factors of their higher viscosity compared to pure water.
Enthalpy and heat capacity of Cs72.9Bi27.1 alloy with a partly ionic character of interatomic interaction in the condensed state
Authors: Stankus S V , Savchenko I V , Khairulin A R , Yatsuk O S
Published: December 2019

The enthalpy of solid and liquid Cs72.9Bi27.1 alloy was measured by a mixing method on a massive isothermal drop calorimeter in the temperature range of 432–1177 K. Approximation equations were obtained. The isobaric heat capacity and enthalpy change on melting were determined. The estimated errors for enthalpy and heat capacity were 0.5 and 1.5%, respectively. A significant positive deviation of the caloric properties from the additivity values was established. Tables of recommended values of caloric properties over the range from 298.15 K to 1175 K were developed.
Physico-chemical characteristics and amino acid profile of fermented sauce made from tuna loin by-product
Authors: Wenno M R , Loppies C R M
Published: December 2019

The processing of tuna loin produces by-products which can be used to increase the total economic value of tuna. One way to use these by-products is to make fish sauce through a fermentation process. Fermentation can increase the nutritional value and extend the shelf life of the product. This study aimed to determine the physico-chemical characteristics and amino acid profiles of fermented fish sauce made from tuna loin by-products. All experimental treatments were conducted with three replicates. The data are reported as mean values ± standard deviation. Physical characteristics measured included colour (L: 4, a: 0.6, b: 2.3) and viscosity (9.58 cP). Chemical characteristics measured included salt content (26.57%); acidity (0.11%), pH (5.00), TVBN (26.00 mg% N), Protein (11.30%), and moisture content (59.00%). The amino acid with the highest concentration was glutamate (1.01%).
The stability of mangrove ecosystems for edu-tourism based on macrozoobenthos ecological indicators in the educational fish ponds of Hasanuddin University
Authors: Saru A , Lanuru M , Mashoreng S , Jubhari Y , Ilham M
Published: December 2019

This study was conducted from June to November 2018 around the educational fish ponds of Hasanuddin University, Bojo Village, Mallusetasi Sub-District, Barru District, Indonesia. This study aimed to identify the mangrove species present, the crustacean and molluscan macrozoobenthos associated with the mangrove ecosystem, and to evaluate the level of stability of the mangrove ecosystem for the development of edu-tourism activities at the study site employing a Macrozoobenthos Ecological Index. Data on mangrove, macrozoobenthos, and other environmental parameters, were collected at five stations with three replicates per station. Mangrove data was collected within 10 m × 10 m plots, while macrozoobenthos were collected with a shovel and sieve net. Seven mangrove species were found: Avicennia marina, Bruguiera gymnorhiza, Ceriops decandra, Rhizophora apiculata, Rhizophora mucronata, Rhizophora stylosa, and Sonneratia alba. The width of the mangrove belt ranged from 28.23 to 57.00 m meaning that it was well below the national green belt standard (50-200 m). The organisms associated with mangroves included crustaceans (three species) and molluscs (seven species) with an abundance of 0.01 - 0.07 ind/m2. The Diversity Index was in the average category (1.49 - 1.92), while the Evenness Index ranged from unstable to under pressure (0.476 to 0.64). The Dominance Index was in the unstable category (0.185 - 0.264). Based on the Macrozoobenthos Ecology Indicator, the mangrove ecosystem in the fish ponds was categorised as stable to average. The land suitability analysis indicated that the mangrove ecosystem in the study site was in the conditionally appropriate category for the development of mangrove edu-tourism activities.
Habitat characteristics and distribution of flyingfish in Fak-Fak and surrounding waters
Authors: Boli P , Luhulima I , Simatauw F , Leatemia S , Tabay S , Parenden D , Ananta A S
Published: December 2019

In Indonesia, flyingfish are abundant and distributed in Makassar Strait, Flores Sea, Banda Sea, Sulawesi Sea, Maluku Sea, Arafura, Northern Sea of Papua, and Halmahera. The aims of this study were to analyse and describe the characteristics of flyingfish habitat, based on oceanographic conditions and eggs catches, and to visualize the variability in spatial and temporal patterns of predicted potential spawning grounds. The research was conducted in Fak-Fak and adjacent seas in the Indonesian Fisheries Area WPP 715, from 130°−134° E and 2°S−5° S. Data were collected during 2018 for selected months: June, July, August and September. Remote sensing data used in this study included chlorophyll-a concentration (Chl-a) OCI-Algorithm, Sea Surface Temperature (SST) 11μ daytime, Absolute Dynamic Topography (ADT), Significant Wave Height and Ocean Surface Current (meridian and zonal components). Fishery data were collected from fishermen’s GPS units, and through participatory mapping. Based on the mapping of fishing locations of flyingfish fishermen, there were four locations where fishing frequency was high. The potential fishing grounds were approximately 5-40 miles from mainland of Fak-Fak. Chlorophyll-a concentration in Fak-Fak waters ranged from 0.201–2.13 mg/m3. The temperature was estimated to be in the range of 27-31°C, with an average temperature of 27.1°C. ADT only changed by 0.01 cm in height each month with a range between 0.88–1.02 cm. Wind was one of the driving forces of geostrophic current. The waves reached a peak in August, with heights ranging from 0.70 to 1.6 metre. Flyingfish were predominantly found in oceanic zones.
The Fishing Ground of Large Pelagic Fish during the Southeast Monsoon in Indonesian Fisheries Management Area-713
Authors: Safruddin  , Aswar B , Ashar M Rijal , Hidayat R , Dewi Y K , Umar M. T , Farhum S. A , Mallawa A , Zainuddin M
Published: December 2019

Large pelagic fish (LPF hereafter) is an important group of fishes targeted by local fishermen in the Indonesian Fisheries Management Area-713 (IFMA-713). This IFMA includes the Makassar Strait, Flores Sea, Bali Sea, and Gulf of Bone. The objective of this study was to identify the preferred oceanographic conditions based on LPF fishing grounds in the study area. The experimental fishing was conducted from April to September 2018 by using local commercial fisheries (pole and line and purse seine). The fishing base of pole and line vessels operating in the Gulf of Bone was at Murante fish landing site, Luwu Regency, South Sulawesi. On the other hand, the fishing base of purse seine vessels operating in the Makassar Strait was at Siddo fish landing site, Barru Regency, also in South Sulawesi. Oceanographic factors such as sea surface temperature (SST), sea surface chlorophyll-a (SSC) concentration, and depth were derived from satellite data. The LPF fishing grounds were analysed and visualize using Geographic Information System (GIS) techniques. Based on the results, LPF distributions tended to be the highest in specific oceanographic conditions, including SST of 30.0 - 31.0 °C and SSC of 0.20 - 0.30 mg.m−3. They were mostly found in nearshore and offshore areas (maximum depth of about 2,000 m). The selected oceanographic factors played an important role in explaining the LPF fishing grounds. This information could be used for spatial prediction of potential LPF fishing zones in relation to the fish distribution and abundance during the Southeast monsoon in the IFMA-713.
Histopathological changes in the intestine of Channa micropeltes infected with the cestode Senga rostellarae
Authors: Hassan Marina , Hadi Muhammad Syafiq Izzuddin Abdul , Aziz Mohd Fazrul Hisam Abd , Wahab Wahidah , Abdullah Farizan , Deraman Shuhaimi , Kismiyati  , Zakariah Mohd Ihwan
Published: December 2019

Channa micropeltes or toman is a native freshwater fish species and not commercially species in Malaysia. The fish become one of the anglers’ attractions to Kenyir Lake, especially for recreational fishing purpose. However, parasitic diseases are one of the most common problems for this fish population. Studies on parasites of C. micropeltes is essential to our knowledge for the maintenance of natural resources. So, the objectives of this study were to identify the cestode and observe the histopathological changes on gastrointestinal tract of infected C. micropeltes. About 15 C. micropeltes were caught by using fishing rod. The fish were pithing, dissected and gastrointestinal tract was removed, then placed on petri dish. The stomach and intestine were fixed in 10% buffered formalin and proceed for preparing histology slides by using standard method for histology. Then, the tissues were stained by using hematoxylin and eosin (H & E) stain. The tissue changes were described. The cestodes were collected, fixed in 70% ethanol, stained with aceto-carmine and prepared the permanent slide. The cestodes morphology were observed under microscope for identification. In this study, only Senga rostellarae was identified. The histopathological changes showed the intestine with severe villus damage with destruction of villi epithelium and necrosis. Some areas with cross section of cestode showed increase of goblet cells and generated necrosis. Based on this study, S. rostellarae was a dominant species, and its activities caused severe damage to the fish intestine. The conditions can cause death to the fish due to hemorrhage and malabsorption of nutrient.