bluuebunny/crossref_metadata_2025 huggingface dataset:
Asymmetric double-layer charging in a cylindrical nanopore under closed confinement
Authors: Matse Mpumelelo , Berg Peter , Eikerling Michael
Published: February 2020

This article presents a physical–mathematical treatment and numerical simulations of electric double layer charging in a closed, finite, and cylindrical nanopore of circular cross section, embedded in a polymeric host with charged walls and sealed at both ends by metal electrodes under an external voltage bias. Modified Poisson–Nernst–Planck equations were used to account for finite ion sizes, subject to an electroneutrality condition. The time evolution of the formation and relaxation of the double layers was explored. Moreover, equilibrium ion distributions and differential capacitance curves were investigated as functions of the pore surface charge density, electrolyte concentration, ion sizes, and pore size. Asymmetric properties of the differential capacitance curves reveal that the structure of the double layer near each electrode is controlled by the charge concentration along the pore surface and by charge asymmetry in the electrolyte. These results carry implications for accurately simulating cylindrical capacitors and electroactuators.
Mixed convection in gravity-driven thin nano-liquid film flow with homogeneous–heterogeneous reactions
Authors: Ahmed Sohail , Xu Hang
Published: February 2020

A modified nanofluid model for homogeneous–heterogeneous reactions in a gravity-driven liquid film is proposed based on the assumptions of the homogeneous reaction governed by isothermal cubic autocatalytic kinetics and the heterogeneous reaction given by first-order kinetics. The Buongiorno model is introduced to describe behaviors of nanofluids with the Boussinesq approximation being used for simplification of the buoyancy term. Multiple solutions are captured, whose stabilities are checked and discussed based on the theory of Sturm–Liouville. The influence of various physical parameters on important physical quantities is presented for different cases, including buoyancy assisting, no buoyancy, and buoyancy opposing. Different from previous studies on chemical reactions in which reactants are presumed in nanometer scale, we assume that the chemical species are of regular size, which react with each other in a nanofluid. This configuration makes our model physically more realistic than previous ones.
Systematic and variational truncation of the configuration space in the multiconfiguration time-dependent Hartree method: The MCTDH[n] hierarchy
Authors: Madsen Niels Kristian , Hansen Mads Bøttger , Worth Graham A. , Christiansen Ove
Published: February 2020

The multiconfiguration time-dependent Hartree (MCTDH) method is a powerful method for solving the time-dependent Schrödinger equation in quantum molecular dynamics. It is, however, hampered by the so-called curse of dimensionality which results in exponential scaling with respect to the number of degrees of freedom in the system and, thus, limits its applicability to small- and medium-sized molecules. To avoid this scaling, we derive equations of motion for a series of truncated MCTDH methods using a many-mode second-quantization formulation where the configuration space is restricted based on mode-combination levels as also done in the vibrational configuration interaction and vibrational coupled cluster methods for solving the time-independent Schrödinger equation. The full MCTDH wave function is invariant with respect to the choice of constraint (or gauge) operators, but restricting the configuration space removes this invariance. We, thus, analyze the remaining redundancies and derive equations for variationally optimizing the non-redundant matrix elements of the constraint operators. As an alternative, we also present a constraint that keeps the density matrices block diagonal during the propagation and the two choices are compared. Example calculations are performed on formyl fluoride and a series of high-dimensional Henon–Heiles potentials. The results show that the MCTDH[n] methods can be applied to large systems and that an optimal choice of constraint operators is key to obtaining the correct physical behavior of the wave function.
Microscopic Richtmyer–Meshkov instability under strong shock
Authors: Sun Pengyue , Ding Juchun , Huang Shenghong , Luo Xisheng , Cheng Wan
Published: February 2020

The microscopic-scale Richtmyer–Meshkov instability (RMI) of a single-mode dense-gas interface is studied by the molecular dynamics approach. Physically realistic evolution processes involving the non-equilibrium effects such as diffusion, dissipation, and thermal conduction are examined for different shock strengths. Different dependence of the perturbation growth on the shock strength is found for the first time. Specifically, the amplitude growths for cases with relatively lower shock Mach numbers (Ma = 1.9, 2.4, 2.9) exhibit an evident discrepancy from a very early stage, whereas for cases with higher Mach numbers (Ma = 4.9, 9.0, 16.0), their amplitude variations with time match quite well during the whole simulation time. Such different behaviors are ascribed to the viscosity effect that plays a crucial role in the microscale RMI. The compressible linear theory of Yang et al. [“Small amplitude theory of Richtmyer–Meshkov instability,” Phys. Fluids 6(5), 1856–1873 (1994)] accounting for the viscosity dissipation provides a reasonable prediction of the simulated linear growth rate. Furthermore, a modified compressible nonlinear model [Q. Zhang et al., “Quantitative theory for the growth rate and amplitude of the compressible Richtmyer–Meshkov instability at all density ratios,” Phys. Rev. Lett. 121, 174502 (2018)] considering both the viscosity effect and the corrected linear growth rate is proposed, which gives an excellent forecast of the linear and nonlinear growths of the present microscale RMI.
Determining absolute Seebeck coefficients from relative thermopower measurements of thin films and nanostructures
Authors: Mason S. J. , Hojem A. , Wesenberg D. J. , Avery A. D. , Zink B. L.
Published: February 2020

Measurements of thermoelectric effects such as the Seebeck effect, the generation of electric field in response to an applied thermal gradient, are important for a range of thin films and nanostructures used in nanoscale devices subject to heating. In many cases, a clear understanding of the fundamental physics of these devices requires knowledge of the intrinsic thermoelectric properties of the material, rather than the so-called “relative” quantity that comes directly from measurements and always includes contributions from the voltage leads. However, for a thin film or nanostructure, determining the absolute Seebeck coefficient, αabs, is challenging. Here, we first overview the challenges for measuring αabs and then present an approach for determining αabs for thin films from relative measurements made with a micromachined thermal isolation platform at temperatures between 77 and 350K. This relies on a relatively simple theoretical description based on the Mott relation for a thin film sample as a function of thickness. We demonstrate this technique for a range of metal thin films, which show that αabs almost never matches expectations from tabulated bulk values, and that for some metals (most notably gold) even the sign of αabs can be reversed. We also comment on the role of phonon and magnon drag for some metal films.
Quantum dot arrays in silicon and germanium
Authors: Lawrie W. I. L. , Eenink H. G. J. , Hendrickx N. W. , Boter J. M. , Petit L. , Amitonov S. V. , Lodari M. , Paquelet Wuetz B. , Volk C. , Philips S. G. J. , Droulers G. , Kalhor N. , van Riggelen F. , Brousse D. , Sammak A. , Vandersypen L. M. K. , Scappucci G. , Veldhorst M.
Published: February 2020

Electrons and holes confined in quantum dots define excellent building blocks for quantum emergence, simulation, and computation. Silicon and germanium are compatible with standard semiconductor manufacturing and contain stable isotopes with zero nuclear spin, thereby serving as excellent hosts for spins with long quantum coherence. Here, we demonstrate quantum dot arrays in a silicon metal-oxide-semiconductor (SiMOS), strained silicon (Si/SiGe), and strained germanium (Ge/SiGe). We fabricate using a multi-layer technique to achieve tightly confined quantum dots and compare integration processes. While SiMOS can benefit from a larger temperature budget and Ge/SiGe can make an Ohmic contact to metals, the overlapping gate structure to define the quantum dots can be based on a nearly identical integration. We realize charge sensing in each platform, for the first time in Ge/SiGe, and demonstrate fully functional linear and two-dimensional arrays where all quantum dots can be depleted to the last charge state. In Si/SiGe, we tune a quintuple quantum dot using the N + 1 method to simultaneously reach the few electron regime for each quantum dot. We compare capacitive crosstalk and find it to be the smallest in SiMOS, relevant for the tuning of quantum dot arrays. We put these results into perspective for quantum technology and identify industrial qubits, hybrid technology, automated tuning, and two-dimensional qubit arrays as four key trajectories that, when combined, enable fault-tolerant quantum computation.
Chemical analysis and origin of the smell of line-dried laundry
Authors: Pugliese Silvia , Jespersen Malte Frydenlund , Pernov Jakob Boyd , Shenolikar Justin , Nygaard Jesper , Nielsen Ole John , Johnson Matthew S.
Published: February 2020

Environmental contextThe fresh pleasant smell of laundry dried outside in sunlight is recognised by most people, but despite decades of speculation the origin of the smell has not been demonstrated. We show that the smell of line-dried laundry is due to the unique combination of traces of atmospheric hydrocarbons, sunlight and a wet fabric surface. This surface photochemistry is likely to be widespread in the environment on surfaces of natural materials. AbstractIn this study, we find that the drying method is the key element in generating the well-known fresh scent of line-dried laundry, which we argue demonstrates that it is the result of physical and chemical processes occurring on the surface of the fabric. Cotton towels were rinsed with Milli-Q water and dried outdoors, indoors, and outdoors but not exposed to sunlight. The dried towels were placed in sealed Tedlar bags, and the emitted compounds were analysed by using thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS) to yield qualitative gas chromatograms and mass spectra. We observed a variety of C5 to C9 oxidised carbon compounds (e.g. aldehydes such as pentanal, hexanal, heptanal, octanal, and nonanal) when the towels were dried outside. These compounds are not observed in the other conditions. Many of these compounds have smells that are subjectively found to be pleasant. The experiments indicate that both UV light and the presence of liquid water are necessary to generate the products. The polar nature of the oxidised compounds may explain why the smell of fresh laundry is relatively long-lasting because hydrogen bonds can form between these compounds and cotton fibres. We therefore propose that oxidative photochemistry on the surface of the drying laundry is responsible for the production of the fresh smell.
Applying semantic gravity wave profiles to develop undergraduate students’ academic literacy
Authors: Brooke Mark
Published: February 2020

This study draws on Legitimation Code Theory (LCT), particularly semantic gravity waving, as a strategy for
academic literacies practitioners to conceptualise how knowledge in their field might be organised and presented. Students can be
guided to notice meanings related to context-dependency at the discourse and lexico-grammatical levels through the presentation of
semantic gravity waving profiles. For this study, semantic gravity waving profiles have been found useful for explaining the
rationale of a genre pedagogy approach, the structure of an Introduction-Method-Results-Discussion (IMRD) genre, and teaching both
lexical coherence for a theoretical framework section, and accurate use of determiners with non-count abstract nouns such as
“research”. Therefore, semantic gravity profiling seems to provide explanatory power as a pedagogical tool in the classroom.
Findings from a mixed method survey with sixty students as well as extracts from student texts before and after semantic gravity
waving profile pedagogical interventions are provided.
The examination of mental toughness, sleep, mood and injury rates in an Arctic ultra‐marathon
Authors: Graham Scott Murray , Martindale Russell J. J. , McKinley Mairi , Connaboy Chris , Andronikos Georgios , Susmarski Adam
Published: February 2020

There is scarcity of research examining the physiological and psychological effects of ultra‐endurance racing on athletes in extreme conditions. The purpose of the current study was to identify common injury patterns and illness, profile mood states and sleep patterns and finally examine the relationships between mental toughness, sleep, mood and injury rates during a 120 mile, three‐day Arctic ultra‐marathon. Twelve participants (3 females, 9 males) with a mean age of 42 ± 5.35 yrs participated in the study. Mental toughness was measured using the MT18 questionnaire. Injuries were clinically assessed and recorded each day. Temperatures ranged from −20 to −6 degrees Celsius throughout the race. Sleep quantity and mood state were recorded using the BRUMS questionnaire. 10 out of the 12 participants experienced injuries; almost half of the participants had injuries that carried over a number of days. Mean sleep duration over the three days was 4.07 h, with an average of 0.78 injuries per day. Significant changes in mood were recorded across the three days, specifically a reduction in vigour (p = .029) and increase in fatigue (p = .014). Neither sleep quantity nor mental toughness was correlated with injury rate. Interestingly, sleep quantity was not related to changes in mood, as previously shown in ultra‐marathons. Mental toughness had a moderate negative correlation (p < 0.01) with depression (−.623), reduced anger (−.616), confusion (−.558), increased vigour (.497) and tension (−.420) during the race. Success in this type of event involves significant psychological and physiological preparation to minimize the effects of sleep deprivation and avoidance of injuries.
Homozygous STAT2 gain-of-function mutation by loss of USP18 activity in a patient with type I interferonopathy
Authors: Gruber Conor , Martin-Fernandez Marta , Ailal Fatima , Qiu Xueer , Taft Justin , Altman Jennie , Rosain Jérémie , Buta Sofija , Bousfiha Aziz , Casanova Jean-Laurent , Bustamante Jacinta , Bogunovic Dusan
Published: February 2020

Type I interferonopathies are monogenic disorders characterized by enhanced type I interferon (IFN-I) cytokine activity. Inherited USP18 and ISG15 deficiencies underlie type I interferonopathies by preventing the regulation of late responses to IFN-I. Specifically, USP18, being stabilized by ISG15, sterically hinders JAK1 from binding to the IFNAR2 subunit of the IFN-I receptor. We report an infant who died of autoinflammation due to a homozygous missense mutation (R148Q) in STAT2. The variant is a gain of function (GOF) for induction of the late, but not early, response to IFN-I. Surprisingly, the mutation does not enhance the intrinsic activity of the STAT2-containing transcriptional complex responsible for IFN-I–stimulated gene induction. Rather, the STAT2 R148Q variant is a GOF because it fails to appropriately traffic USP18 to IFNAR2, thereby preventing USP18 from negatively regulating responses to IFN-I. Homozygosity for STAT2 R148Q represents a novel molecular and clinical phenocopy of inherited USP18 deficiency, which, together with inherited ISG15 deficiency, defines a group of type I interferonopathies characterized by an impaired regulation of late cellular responses to IFN-I.
Characterisation of a deep-ultraviolet light-emitting diode emission pattern via fluorescence
Authors: McFarlane Mollie , McConnell Gail
Published: February 2020

Recent advances in LED technology have allowed the development of high-brightness deep-UV LEDs with potential applications in water purification, gas sensing and as excitation sources in fluorescence microscopy. The emission pattern of an LED is the angular distribution of emission intensity and can be mathematically modelled or measured using a camera, although a general model is difficult to obtain and most CMOS and CCD cameras have low sensitivity in the deep-UV. We report a fluorescence-based method to determine the emission pattern of a deep-UV LED, achieved by converting 280 nm radiation into visible light via fluorescence such that it can be detected by a standard CMOS camera. We find that the emission pattern of the LED is consistent with the Lambertian trend typically obtained in planar LED packages to an accuracy of 99.6%. We also demonstrate the ability of the technique to distinguish between LED packaging types.
Effect of AlGaN interlayer on luminous efficiency and reliability of GaN-based green LEDs on silicon substrate*
Authors: Guo Jiao-Xin , Ding Jie , Mo Chun-Lan , Zheng Chang-Da , Pan Shuan , Jiang Feng-Yi
Published: February 2020

The effect of AlGaN interlayer in quantum barrier on the electroluminescence characteristics of GaN-based green light emitting diodes (LEDs) grown on silicon substrate was investigated. The results show that AlGaN interlayer is beneficial to improve the luminous efficiency of LED devices and restrain the phase separation of InGaN. The former is ascribed to the inserted AlGaN layers can play a key role in determining the carrier distribution and screening dislocations in the active region, and the latter is attributed to the increased compressive stress in the quantum well. However, when the electrical stress aging tests were performed at a current density of 100 A/cm2, LED devices with AlGaN interlayers are more likely to induce the generation/proliferation of defects in the active region under the effect of electrical stress, resulting in the reduced light output power at low current density.
Failure analysis with a focus on thermal aspect towards developing safer Na-ion batteries*
Authors: Li Yuqi , Lu Yaxiang , Chen Liquan , Hu Yong-Sheng
Published: February 2020

Safety requirements stimulate Na-based batteries to evolve from high-temperature Na–S batteries to room-temperature Na-ion batteries (NIBs). Even so, NIBs may still cause thermal runaway due to the external unexpected accidents and internal high activity of electrodes or electrolytes, which has not been comprehensively summarized yet. In this review, we summarize the significant advances about the failure mechanisms and related strategies to build safer NIBs from the selection of electrodes, electrolytes and the construction of electrode/electrolyte interfaces. Considering the safety risk, the thermal behaviors are emphasized which will deepen the understanding of thermal stability of different NIBs and accelerate the exploitation of safe NIBs.
A review of flexibility of residential electricity demand as climate solution in four EU countries
Authors: Mata Érika , Ottosson Jonas , Nilsson Johanna
Published: February 2020

Increased flexibility at the grid edge is required to achieve ambitious climate goals and can be provided by smart energy solutions. By systematically reviewing the literature, we provide an overview of the potential flexibility of different residential electrical loads for France, Germany, Sweden, and the United Kingdom. While 85% of the studies aimed to identify potentials for shifting electrical energy use in time, the other 15% aimed to identify energy-saving potentials. Most of the data were found for the German and British electrical systems. A wide range of flexibility measures (e.g. price mechanisms, user-centered control strategies for space heating and water heating, automated shifting of appliances’ use, EV charging algorithms, and consumer feedback) and methods (e.g. simulations, trials, and interviews) have been used. Potentials obtained from the literature have been upscaled to the national level, including corresponding effects in terms of carbon dioxide (CO2) emissions. The results show that between 2% and 18% of residential sector electricity in the four countries could be shifted, resulting in total emission reductions of 10 MtCO2 from peak shaving, or 24 MtCO2 per year if optimizing the deployment of renewables. The literature identifies substantial economic, technical, and behavioral benefits from implementing flexibility measures. In all the cases, it seems that the current regulatory framework would need to change to facilitate participation. Recognized risks include higher peaks and congestions in low price-hours and difficulties in designing electricity tariffs because of conflicts with CO2 intensity as well as potential instability in the entire electricity system caused by tariffs coupling to wholesale electricity pricing.
Research on blackout simulation model considering hidden failures and reclosing
Authors: Qingqing HAO , Qun YU
Published: February 2020

In this paper, a blackout simulation model considering hidden failures and reclosing is proposed, which is more realistic than the previous model. The operation of reclosing devices, the synchronization control for reclosing in two-ended sources transmission lines and the interaction between reclosing and relay protection are simplified. Simulation results of IEEE39-bus test system are obtained to confirm the validity of the model. Compared with the blackout simulation model considering only the hidden failures of relay protection, it shows that the trip caused by the transient faults and hidden failures induced by transient faults can be corrected in this large-scale blackout simulation model. It also shows that with the increase of the probability of hidden failure, the failure rate of reclosing becomes an important factor affecting the system recovery.
Temperature extraction method for infrared image of high voltage power equipment
Authors: Xueyou HUANG , Yu ZHANG , Xianan JIAO , Shuheng MA , Jun XIONG
Published: February 2020

An infrared temperature prediction method for power equipment is proposed based on the radial basis function (RBF) network optimized by quantum genetic algorithm (QGA) and orthogonal least squares algorithm (OLSA). The modified compound algorithm was used to optimize parameters of the RBF network. A temperature prediction model was established through the fitting of pixels and temperatures of the infrared image of an equipment. After image matching, the infrared temperature at a position can be directly obtained from the visible image. Meanwhile, we can also directly read temperature values of different positions from the infrared image and identify the corresponding positions in the visible image. Experimental results indicate that the algorithm proposed has a better prediction performance than the RBF network optimized by OLSA alone and by adaptive genetic algorithm (AGA) and OLSA. It improves the generalization capacity of RBF network, resulting a more stable input and a higher prediction accuracy. The algorithm proposed facilitates temperature analysis and condition-based maintenance for substations.
Reliability assessment of offshore oil platform power system based on state enumeration method
Authors: Wei Che , Du Wei , Wang Xiuli , Luo Xianjue , Li Qiang
Published: February 2020

Based on the state enumeration method, a reliability evaluation method for offshore platform power system is proposed in this paper. Firstly, the reliability model of land-based components and the modelling method of the system are introduced. In reliability evaluation, all fault states are generated based on state enumeration method, power supply circuit sets are identified based on depth-first algorithm. The effects and losses of multiple faults are calculated based on platform maintenance capability, and fault time and load-loss time are separated and counted. Finally, taking an offshore oil platform as an example, the outage table of the system is generated, and the reliability index of the system is obtained, which verifies the effectiveness and accuracy of the method proposed in this paper.
Application research of virtualization in life cycle management of nuclear power computers
Authors: Han Hongbao , Yang Jinqiu , Li Xiaohe , Liu Shengzhi , Pan Weiwei
Published: February 2020

At present, digital instrument control equipment and systems are widely used in nuclear power plants, in which computer is an important component of digital instrument control system. But the upgrading period of software and hardware system is very short. It is often faced with the shutdown of spare parts and the upgrade of software and hardware platform that can’t support the original application software, which brings great challenges to the life management of computer. This paper expounds the application status of computer in the digital instrument and control system of nuclear power, the characteristics of life management, obsolescence solutions and risks, and introduces the virtual server technology. The application cases of Demineralized Water Production System (hereafter called SDA) booster upgrading project in a nuclear power plant are summarized, and the application scope and limitations of virtualization obsolescence management strategy are summarized. The practice shows that virtual server technology can effectively solve the problem of computer life cycle management in some cases, which is conducive to reducing costs and increasing efficiency, and improving the competitiveness of nuclear power.
Comparison of fuel consumption and emission characteristics of china VI coach under different test cycle
Authors: Yu Hanzhengnan , Liu Yu , Li Jingyuan
Published: February 2020

As the test cycle used for evaluating the fuel consumption and emission characteristics of the heavy-duty commercial vehicle in China will be replaced from C-WTVC to CHTC in a round 2020, the investigation on the variation of fuel consumption and emission test results after the replacement is well needed for further vehicle’s development and calibration. In this paper, the fuel consumption and emission characteristics of a China VI coach under these two test cycles have been discussed and compared. Results showed that fuel consumption, CO, HC and NOx emissions of the test coach all increased after changing the test cycle from C-WTVC to CHTC, which were due to the low rotation speed and low torque operating points, and the aggressive and frequent acceleration under CHTC. In addition, Acceleration driving condition contributed most to the deterioration of fuel consumption, CO, HC and NOx emissions under CHTC, which attention should be especially paid in the further vehicle calibration.
Substitution of fermented maggot (Hermetia illucens) flour on commercial feed towards protein retention and energy retention in tambaqui (Colossoma macropomum) meat
Authors: Wantika N , Budiana  , Suryani E , Rubi’ah L , Dzatalini N , Rusdiatin  , Nila Y T , Santanumurti M B , Samara S H , Nindarwi D D , Lokapirnasari W P , Al-Arif M A , Alamsjah M A , Lamid M
Published: February 2020

Colossoma macropomumis one of the fisheries commodities that has high economic value. It is necessary to to use quality feed, such as maggot, to increase its production. Since fish growth is largely influenced by nutrient content in feed and fish energy needs Maggot has high protein content of 40-50% and fat content 29-32%.This study aimed to determine the retention of protein and retention ofColossomamacropomum. This study used an experimental method with a Completely Randomized Design consisting five treatments and four replications. The provided treatment was a commercial feed which was replaced by the maggot fermentation with different doses. The treatments used in this study were: treatment P0 (0%), P1 (12%), P2 (14%), P3 (16%) and P4 (18%). Parameters observed in this study were protein retention and energy retention. This research used Variant Of Analysis (ANOVA) for data analysis. The result showed that the substitution of maggot fermentation flour on commercial feed for 30 days of maintenance was significantly different (p<0,05) on protein retention. While the energy retention, result showed no significantly different (p> 0.05). The protein retention value ofColossoma macropomum’s meat was 7.8568% -10.3620% and the energy retention showed 3.9868% -5.2540%.
The effect of giving commercial feed, beloso trash fish (Saurida tumbil), kurisi trash fish (Nemipterus nematophorus), and mixed trash fish on growth of cantang grouper (Epinephelus fuscoguttatus-lanceolatus) in floating net cage
Authors: Nugraha M A , Rozi
Published: February 2020

An experiment was conducted to observe the effect of commercial feeding, and trash fish feed supplement on cantang grouper fish growth in floating net cages at Situbondo, Indonesia. The method used in this experiment was designed with 4 treatments and 3 replications. Samples (26.49 ± 0.81 cm) were a stocking density of400 fish/cage and maintenance for 30 days. The treatments used were P0;commercial pellets, P1;100% beloso trash fish (Saurida tumbil), P2; 100% kurisi trash fish (Nemipterus nematophorus) and P3; mixed wasted fish; 50% beloso trash fish + 50% kurisi trash fish, with four replicates. The best treatment result is that P0 quantitatively has significant effect on feed growth, survival, and efficiency compared to other treatments; SGR (0.5618%), SR (85%), FCR (3.69), and EPP (27.08%) compared to other treatments. The best treatment result is that P0 quantitatively has significant effect feed on growth, survival, and efficiency feed utilization of cantang grouper (E. fuscoguttatus-lanceolatus) compared to other treatments.
Infection analysis of Rhadinorhynchus bicircumspinis in barramundi (Lates calcarifer) from pond and floating net cage in Situbondo waters.
Authors: Putri D N , Subekti S , Ulkhaq M F , Kusdarwati R , Budi D S , Kenconojati H
Published: February 2020

Barramundi (Lates calcarifer) was known as highly demand of fisheries commodity and exported in many countries. Pond and floating net cage culture of barramundi have several problems that cause many mortality in fish, such as endoparasite infection. This study aims to determine and to count the prevalence and intensity of endoparasite Rhadinorhynchus bicircumspinis in barramundi (L. calcarifer) from pond and floating net cage in Situbondo waters. Sixty samples of barramundi with length 18.18 ± 1.41 cm were taken from ponds and floating net cages and examined for endoparasite from digestive track, liver, gonad and kidney. The result showed endoparasite R. bicircumspinis was found from digestive track with prevalence was 10% and 40% in pond and floating net cage, respectively. The intensity of endoparasite R. bicircumspinis was 1 and 2.5 in pond and net cage, respectively. Further studies were needed to examined the histopathological damage caused by R. bicircumspinis infection.
Population growth and fishery status of the Lorjuk shellfish (Solen sp.) on Pamekasan beaches, Indonesia
Authors: Trisyani N , Kamarudin
Published: February 2020

Solen sp. is classified as a Pelecypoda which is found in certain waters in Indonesia. Solen sp. is utilized as fresh and processed food. Alarmingly, catching Solen sp. continuously will reduce the number of its population in the world. The research aims to determining the population growth of Solen sp. and its fishery status on Talang Siring Beach, Pamekasan. The results of the research show that the range of Solen sp. length is between 1.8 and 4.4 cm. The growth calculation is Lt = 5.5 (1 - e(-0.07(t + 0.006)). The growth of Solen sp. calculated by the ELEFAN I method in the FISAT II software produces the value (L∞ = 5.5 cm, k = 0.07/year). Estimation of the length at time t0 calculated by Pauly’s empirical formula is t0 = -0.006. The natural rate of mortality (M) is 2.23/year, and the capture mortality (F) is 5.72/year and total mortality (Z) is 7.96/year. The exploitation rate (E) is 0.72/year. The conclusion of the research is that the Solen sp. on Talang Siring beach, Pamekasan is overfished. Therefore, it is necessary to regulate a fishing time and protection to Solen sp. so that the population remains everlasting and sustainable.
The effect of fucoxanthin as coloring agent on the quality of catfish sausage
Authors: Aditya N W , Amin M N G , Alamsjah M A
Published: February 2020

Fucoxanthin is the main carotenoid produced from brown seaweed Sargassum sp. Fucoxanthin has an orange color and antioxidant activity. Fucoxanthin as coloring agents and antioxidants can be used to maintain the quality of catfish sausage during storage. The purpose of this study was to determine the effect of incorporating fucoxanthin from Sargassum sp. to color intensity, pH value and peroxide value of catfish sausages during storage. The method was implemented as the experimental method with Completely Randomized Design (CRD). Five different catfish sausages formulations were produced containing 0%, 1%, 2%, 3%, and 4% fucoxanthin. The results showed that the incorporating of fucoxanthin had a significantly different (p <0.05) on the value of color intensity, pH value and peroxide value of catfish sausages during storage. Incorporation of fucoxanthin decreases the * L value, pH value, peroxide value and increases the * a and * b value of catfish sausage. Hedonic test of catfish sausages shows that panelist score on appearance, odor, flavor, texture, color and overall quality were significantly different (p<0.05). Catfish sausage with 1% fucoxanthin is the most preferable by the panelist.
The effect of seaweed (Eucheuma cottonii) age differences as a material on medium density fiberboard (MDF) manufacture
Authors: Arrosyad F H , Alamsjah M A
Published: February 2020

Eucheuma cottonii is a potential type of seaweed because of its abundant production. Its content of lignocellulose could be beneficial in Medium Density Fiberboard (MDF) manufacture since it could increase the market of this kind of seaweed. Lignocellulose itself is influenced by the age of seaweed. The aim of this study was to determine the different age in Eucheuma cottonii which could effect on its physical and mechanical properties of MDF product. Furthermore, the aim was also to investigate whether the product could meet standard set by JIS A 5908 2003. The study was designed using a Completely Randomized Design with five types of treatment and four times replications. This study used Eucheuma cottonii and sawdust. Manufacture of Medium Density Fiberboard (MDF) consisted of five types of treatment: T0: Sawdust 100%, T1: Seaweed 100%, T2: Sawdust 50 % + Seaweed 50 % aged 15 days, T3: Sawdust 50 % + Seaweed 50 % aged 30 days, T4 Sawdust 50 % + Seaweed 50 % aged 45 days. The results showed that different between physical and mechanical test for the each treatment.
Growth performances of Nile Tilapia, Oreochromis niloticus, reared in recirculating aquaculture and active suspension systems
Authors: Amin M , Musdalifah L , Ali M
Published: February 2020

Recirculating aquaculture system (RAS) and active suspension aquaculture system (ASS) are rearing systems which are commonly used in aquaculture productions nowadays. This study aimed at comparing the growth performances of Nile tilapia cultured at the two aquaculture systems for 42 days. The measured parameters were growth rate, weight gain, feed conversion ratio, survival rate, and nutrient utilization (protein efficiency ratio, fat efficiency ratio, and energy efficiency ratio). The results showed that Tilapia reared in the RAS had significantly higher growth rate, weight gain, lower feed conversion ratio, and more efficiently in the utilization of protein, fat, and energy compared to tilapia reared in ASS. These results may indicate that the recirculating aquaculture system provided more comfortable environments for the tilapia for growth compared to the active suspension aquaculture system. However, another study in terms of economic perspective is still required, since the recirculating aquaculture system requires more rearing tanks and operational costs, especially from electricity.
Characterization of nano calcium powder from blood cockle (Anadara sp.) shell produced by using different hydrochloric acid concentration
Authors: Pramudi G Y , Sulmartiwi L , Tjahjaningsih W , Mashitah E D , Patmawati  , Amin M N G
Published: February 2020

Blood cockles one of shellfish which can potentially be developed as a source of protein and minerals. The shell provides a source of calcium, as the structure is similar to that of bone. This research aims to characterize nano calcium powder from blood cockle (Anadara sp.) shell produced by using different hydrochloric acid (HCl) concentrations. Four concentrations vis. 0.5 N, 1.0 N, 1.5 N and 2.0 N were designed by using a completely randomized design. This research revealed that different the concentration affected the particle size and mineral content of the nano calcium powder, where concentration of 1 N was the most appropriate concentration used. The yield generated was 0.82% with the calcium content of 62.89%, the particle size of 454.4nm and high uniformity.
Potential concentration of heavy metal copper (cu) and microalgae growth Spirulina plantesis in culture media
Authors: Budi R M S , Rahardja B S , Masithah E D
Published: February 2020

Water is an important environmental component for life. Heavy metal water pollution comes from many industries. Heavy Metals Copper (Cu) is one of several other heavy metals that are harmful to living things. One way to anticipate the increased pollution of heavy metals Copper (Cu) in waters is bioremediation using microalgae. This study aims to determine the ability of Spirulina plantesis in absorbing heavy metals Copper (Cu) and to determine the influence of heavy metal Copper (Cu) on the growth of Spirulina platensis. This study used an experimental method with Completely Randomized Design (RAL) consisting of four treatments and five replicates, namely A (S. platensis 0 ppm), B (S. platensis 1 ppm), C (S. platensis 3 ppm), D (S. Platensis 5 ppm). The results showed that Spirulina platensis was able to absorb heavy metal of Copper (Cu) so that it can be used as a heavy metal bioremediation agent. On treatment B (1 ppm) absorption of 87,719%, C (3 ppm) equal to 97,886% and D (5ppm) equal to 95,872 % Growth with the addition of Cu affects Spirulina platensis growth
Effect of enzyme papain against natural flavor of raw meat waste laundering surimi
Authors: Harahap N A , Satyantini W H , Sudarno
Published: February 2020

Washing waste material surimi fish meat has the potential to be developed into a natural flavor because it contains of proteins and amino acids are quite high. Enzymatic hydrolysis of proteins can produce compounds savory (umami) which can be used as natural flavor. This study aimed to determine the effect of the enzyme papain as an agent of the natural flavor of the washing waste material surimi fish meat. The treatment includes control of 0% (without the enzyme papain), the addition of the enzyme papain 2%, 4% and 6%. The results showed that administration of different concentrations of the enzyme papain give effect to the yield and the value of the resulting organoleptic flavor. The yield of flavor respectively-helped by 6.18%, 7.23%, 9.98% and 12.03%. Best papain enzyme concentrations in this study were treated with the addition of P2 which papain enzyme 4%, note the value yield of 9.98% with an average rate of acceptance of the panelists of the color, aroma, and flavor are 6; 3.4 and 3.7 which means rather liked, a bit fishy, and rather tasteless fish, the protein content of 15.62%, 0.26% glutamic acid, and water solubility of 96.5%.
Correlation between Serum Galectin-3 Level with Wall Motion Score Index in Patients with ST-Segment Elevation Myocardial Infarction
Authors: Halid K , Aminuddin M , Dewi I P
Published: February 2020

The inflammatory process plays an essential role in the process of atherosclerosis and the response of ventricular recovery after myocardial infarction. Galectin-3 is a mediator derived from macrophages and endothelium that is actively involved in various aspects of the inflammatory cell behavior. Galectin-3 increases in the formation of fibrosis and scar, which is a maladaptive response to injury and infarction such as ST-segment elevation myocardial infarction (STEMI). Wall Motion Score Index (WMSI) is a semiquantitative visual assessment of the dynamic left ventricular wall. WMSI has an association with left ventricular ejection fraction in assessing prognosis after myocardial infarction. This study aimed to determine the correlation of increasing galectin-3 level with WMSI in STEMI patients. A cross-sectional study with purposive sampling was done. Galectin-3 levels were measured using R&D System ELISA Quantikine® Human galectin-3 Immunoassay with units ng/ml. WMSI measured by 2D-echocardiography. We enrolled a total of 35 STEMI patients, 28 (80%) were males. The result of measurement of galectin-3 levels in STEMI patients increase significantly (12,545±6,504 ng/mL) and moderate positive correlation with WMSI (r=+0,429, p=0.01). The result of the study showed there is a significant positive correlation between serum galectin-3 level with WMSI in STEMI patients.
The Effect of Atorvastatin Administration before Percutaneous Coronary Intervention on Stable Coronary Artery Disease Against Event of Periprocedural Myocardial Infarction
Authors: Dewi L P C , Yogiarto R M , Suryawan I G R , Pratama M D
Published: February 2020

Statin administration before Percutaneous Coronary Intervention procedures (PCI) is proved in reducing the incidence of Myocardial Peri-Procedural (PMI) infarction. This research was to compare between of pre-treatment 40mg Atorvastatin administered two hours before PCI in Stable Coronary Artery Disease (SCAD) patient and without pre-treatment in reducing the rate of periprocedural myocardial infarction. This study was a Clinical Trial with pretest-posttest control group open-label randomized design. Data were analyzed using Kolmogorov Smirnov Sample test and Chi Square Test. The PMI incidence in the atorvastatin group was 0% and in the control group was 8.3% (p = 0.489). The maximum CK-MB value after PCI in the atorvastatin group was 6.4ng/ml and 25.49ng/ml in the control group. Administration of 40mg Atorvastatin in SCAD patients before undergoing PCI shows a tendency of a decrease in PMI incidence.
Optimization of test specimen dimensions for thermal power station exposure device
Authors: Chvostová E , Horváth J , Konopík P , Rzepa S , Melzer D
Published: February 2020

Degradation of metallic materials can decrease mechanical properties of metal constructions and components in thermal power plants during their operation and consequently lead to loss of safety and reliability. It is difficult to remove material from the pressure system of the equipment being operated. Therefore, the effort is to design, produce and subsequently install exposure channels, which will allow to remove and evaluate samples of exposed material without intervention into the pressure system. The exposure device for pressures and steam temperature in supercritical blocks, which would contain sufficient test material to produce conventional test specimens, is unrealistic in size, energy and economics. The way is to optimize the dimensions of the exposure device according to the miniaturized test specimens, which, in addition to the tensile test and the structural evaluation, can also carry out other required tests, such as bending impact tests with transition temperature, fracture toughness and fatigue tests. This paper deals with optimization of test specimens for the internal dimensions of the exposure device and shows the applicability of small sample methodologies for selected materials.
The effect of mechanical surface pre-treatment on the strength of the adhesive joint of high strength sheets
Authors: Kejzlar P , Seibert O , Pilvousek T
Published: February 2020

Nowadays, in the car body parts production, the quenching is often replaced by adhesive joints. The adhesive joints have a lot of advantages – they allow to keep the protective layer, enable to join different material and prevent from the formation of heat affected zones. With respect to passenger’s passive safety, plenty of car body parts are manufactured of high strength steel sheets. The body parts are hot-formed at a temperature of 900 °C to the desired shape followed by subsequent rapid quenching to achieve the required strength. The sheets are covered with an AlSi 60/60 layer which should protect them from high-temperature oxidation during the forming process. However, brittle intermetallic interlayers form during the high-temperature treatment due to the reaction of iron from the substrate with Al/Si from the protective cover, which negatively affects the final strength of adhesion joint. The paper deals with the comparison of different possible ways of removing the layer on the final strength.
Optimization of workability technological testing for open-die forging
Authors: Kotous Jakub , Kubec Václav , Duchek Michal , Studecký Tomáš
Published: February 2020

Developing an open-die forging process for a poor-workability alloy has always been a challenge. This paper presents a rapid method that meets this purpose. A simplified forging test was considered for assessing the limit states of material in open-die forging. It can be employed in industrial forge shops. A V-shaped testing die was designed using finite element (FE) simulation. The V-shape geometry is convenient for strain evaluation. Rectangular blocks will be tested across a wide range of working temperatures. Based on the test results, limit states can be identified. Then friction testing method was optimized. It is also simple comparison test. Both technological tests are suitable for determination of optimized parameters in forging. The risk of material failure can thus be eliminated or minimized.
Effect of revolutions number on mechanical properties of HPT processed copper
Authors: Melzer D , Smirnov I , Evstifeev A , Rzepa S , Konopík P
Published: February 2020

This paper studies the effect of high-pressure torsion (HPT) method at ambient temperature on mechanical properties of material. The aim is to compare copper subjected to HPT for 2, 10 and 30-revolutions with coarse grain structured copper in a cold-rolled state. Miniaturized tensile tests were performed to evaluate anisotropy of mechanical properties within a disc product of HPT process. Also the strain rate sensitivity was examined. The results of mechanical tests demonstrate that increasing shear strain leads to ultra-fine grain structure (UFG) which resulted in increasing of material strength. The plasticity of material decreases correspondingly to that. With respect to character of HPT process, discs are known as non-homogenous products, where shear strain effect increases in radial direction from the centre section to the edge. Results show that with different number of HPT revolutions the anisotropy of mechanical behaviour is changing. With increasing number of revolutions the anisotropy within a single disc is increasing.
Flash pulse phase thermography for a paint thickness determination
Authors: Muzika L , Švantner M
Published: February 2020

The contribution describes a fast contactless measurement of a paint thickness non-uniformity using flash pulse thermography. Specimens sprayed by a paint were thermally excited by a flash lamp and temperature responses were recorded by an infrared camera. The recorded sequences were post-processed with Fast Fourier Transform to obtain phase angles. Differences in the resulting images showed phase differences which corresponded to a paint thickness non-uniformity. Furthermore, the phases were correlated with the thickness by means of calibration curve so that the paint thickness could be determined with flash pulse phase thermography measurement. The method showed a promising potential in the contactless evaluation of the paint thickness. Average error of the thickness determination was less than 10 % for samples with paint thickness from 41 to 74 µm on AISI 304 substrate. Advantages, disadvantages and limitations of described method were discussed.