bluuebunny/crossref_metadata_2025 huggingface dataset:
Anthocyanin content in mature/immature blueberry fruits under different storage temperature
Authors: Li Yuan , Huang Jinqiu , Wang Zhihui , Wang Xun
Published: September 2019

The anthocyanins in blueberry ‘Brigitta’ mature and immature (purple) fruits stored in different temperature (4°C and 25°C) were analyzed by HPLC. The results showed that ‘Brigitta’ blueberry contained 9 anthocyanins. Anthocyanins contents in the purple fruit stored in 4° showed a trend of previous rise and end fall. In the mature fruit under 25°, anthocyanins contents kept on rising. In the mature fruits at 4° and purple fruits at 25°, same trends of decline first and then rose were revealed. This study suggested that in a certain storing during, anthocyanins contents in blueberry fruit fluctuated.
Common features in the manifestation of natural and induced geodynamic events in the eastern regions of Russia and China
Authors: Yu Lijiang , Ignatov Yuriy , Ivannikov Alexander , Khotchenkov Evgeny , Krasnoshtanov Daniil
Published: September 2019

The study of geodynamic processes observed in the Earth’s crust at densely populated and commercially developed areas in the east of Russia and China is of great importance for their sustainable development. The research results available show that not only natural, but also man-made geodynamic events associated with mining operations reflect the global geodynamic processes. Geodynamic events that occurred while mining in impact-hazardous areas allowed to identify some common features in the manifestation of natural and man-made geodynamic events in the eastern regions of Russia and China. Thus, both natural and disastrous technogenic geodynamic events (tectonic rock bursts, induced earthquakes, cracking on the earth’s surface) have positional connection with the linear zones of earth’s crust modern destruction (block boundaries and faults). Existing tectonic faults get re-activated during major geodynamic events, i.e. they get displaced in response to the mining operations. Areas hazardous for manifestation of geodynamic phenomena can be defined by geodynamic zoning method which can be used to draft the development programs for the eastern regions of Russia and China
The state of stress in the aftershock area of the March 11, 2011 Tohoku earthquake
Authors: Rebetsky Yu L , Yu Polets A
Published: September 2019

This paper presents the results of the stress inversion in the Earth’s crust in the Japanese seismic focal zone after the Tohoku earthquake of March 11, 2011. The stress tensor parameters are determined using the method of cataclastic analysis (MCA) of discontinuous displacements. The reconstruction of the stress state is based on earthquake focal mechanism data for magnitude range (Mw) 3.0–6.0. The calculations are performed at six depths. The 2011 Tohoku earthquake brought significant stress changes in the upper layers of the lithosphere of the continental slope (0-30 km). These changes have led to the emerging of extensive areas of horizontal extension here. The areas with changed geodynamic regime were not reduced over the past few years. The magnitude 9.0 Tohoku earthquake was a catastrophic mega earthquake and in this case the presence of an anomalous state of stress may take a long time.
Seismic regime of south Sakhalin before the Krillon earthquake 23.04.2017 (LURR and SDP models)
Authors: Zakupin A S
Published: September 2019

In the present work we show a fundamental possibility of a short-term prediction of strong shallow-focus earthquakes in the Southern Sakhalin (on the Krillon earthquake example, 23.04.2017, Mw=5.0). Retrospective modeling of earthquakes sequences from 2013 to 2017 based on the method of self-developing process (SDP) and the catalogue data of the local network has required. An auxiliary tool was used to improve the accuracy of the SDP estimates. It is a medium-term earthquake prediction method called LURR (load-unload response ratio). The previous results were improved using different sample data in the zones of active fault structures. This avoids ambiguity in the choice of the computational domain for SDP calculations. The zone of maximal anomalous levels of LURR coincides with that one we obtained a solution by the method of SDP. It happened 77 days before the earthquake. When compared with average estimates by the LURR method (two years), the prediction time was concluded to go down by 11 times.
About seismic observations on Sakhalin with the use of molecular-electronic seismic sensors of new type
Authors: Kostylev D V , Bogomolov L M , Boginskaya N V
Published: September 2019

To conduct complex geophysical observations in the area of the Central Sakhalin Fault, an experimental geophysical test site was created, including a broadband molecular electronic type station and a new development of the Molecular Electronics Center - molecular electronic hydrophone. A module for placing a molecular-electronic seismometer at the test site has been developed and arranged. The noise level of the seismometer was analyzed and compared with the reference data. The results of hydroacoustic observations of weak earthquakes in the area of the Central-Sakhalin fault using a molecular-electron hydrophone are presented. The characteristics of the recorded acoustic emission signals from earthquakes perceived by the hydrophone station (frequency spectrum, arrival times of seismic waves) are investigated. The issues of operation and maintenance of molecular-electronic sensors with seismic signal data logger at various stages of seismological observations (setting up equipment, acquisition and storing data) were considered. The analysis of recording capabilities of seismic equipment was performed. Conclusions about the advantages and disadvantages of molecular-electronic sensors and their use on Sakhalin are made.
The stress state of the Sakhalin Island and adjacent territories
Authors: Yu Polets A
Published: September 2019

The present study presents the results of the stress tensor inversion in the Sakhalin-Island and adjacent territories. The method of cataclastic analysis of discontinuous displacements has been used to perform the stress reconstruction. The stress inversion has been performed on the basis of local focal mechanism solution catalog of earthquakes, NEID and Global CMT Project data. The calculations are carried out at three depths levels (0–6 km, 6–12 km and 12–18 km) for magnitude range (Mw) 3.0–7.0. The results of the stress reconstruction allowed us to obtain the new specific features of the tectonic stress field: orientation of the principal stress axes, stress ratio or Lode-Nadai coefficient and the types of stress (the geodynamic regimes). The tectonic stress field is less stable at depth between 6 and 12 km.
The ratio of tectonic structure and modern movements of the crust in area of geodynamic proving ground in Bishkek
Authors: Kuzikov S I
Published: September 2019

According to the various scale GPS measurements, the process of collision between India and Eurasia is still ongoing and is reflected on Central Asia territory. The maximum velocity of shortening on northern component between India and Asia is ∼35 mm/year; the longitudinal (east-west) extension of the Tien Shan is ∼20 mm/year. The maximum deformations of shortening ∼15 mm/year along the north coordinate operate in a narrow fault zone between the Pamir and Tien Shan. Not on all Cenozoic (neotectonic) faults occur modern movements of the earth’s crust, these faults may have separate segments of active at different times. The general kinematic tendencies of modern movements correlate well enough with the general kinematic structure of neotectonic faults. In the fault zones at distances from the first hundreds meters to the first kilometers, intense elastic changes in the baseline lengths up to 4 cm (strains of 10–4) can occur within a week and up to 3-5 months. Such high-frequency elastic events have a different character of manifestations and are 2-4 orders of magnitude greater level than stable many years’ residual deformations.
Numerical modeling of the 2015 Illapel Tsunami source by the inversion of DART buoys data
Authors: Voronina T.A. , Loskutov A.V.
Published: September 2019

The problem of the tsunami source reconstruction from the remote measurements of an arriving waves in the deep-water tsunamimeters is considered as an inverse problem of mathematical physics in the class of the ill-posed problems. The latter determines the inevitable instability of the numerical solution. We propose a method providing more control on the numerical instability of the solution. The DART buoys data allows one to apply the linear shallow-water theory for the wave propagation and the r-solution method for the tsunami waveform inversion. The applied approach is independent from the earthquake source characteristics, because the only observed tsunami waveforms and a roughly estimated tsunami source area are used. A good coincidence of observed and computed tsunami waveforms was a criterion of the quality of the inversion. In this paper we study the 16 September 2015 Illapel (Chile) event and conduct a reconstruction of a tsunami source.
Volcanic activity in the Kuril Islands in 2018: on the basis of satellite and visual data
Authors: Chibisova M V , Rybin A V , Degterev A V
Published: September 2019

The data characterizing volcanic activity in the Kuril Islands in 2018 are given on the basis of satellite and visual data. The Ebeko volcano (Paramushir island, the Northern Kuriles) and Sarychev Peak volcano (Matua Island, the Central Kuriles) were active in the Kuril Islands. On Ebeko volcano a weak (to moderate) explosive eruption occurred, it expressed in regular steam and ash-gas emissions (only about 800 with a height from 2 to 5.5 km). Sarychev Peak volcano was characterized by a manifestation of weak (to moderate) explosive activity (during the period from September till October there were at least 10 emissions to a height of 2 to 4.5 km). Due to the relatively low emission height and low ash concentration, the activity of Ebeko and Sarychev Peak volcanoes in 2018 did not pose a serious threat to international air routes, but could complicate the work of local airlines.
Geological and geomorphological processes impacting nature management in the coastal zone of Pacific Russia
Authors: Govorushko S M
Published: September 2019

The coastal zone of Pacific Russia (administrative areas of the Far East with access to the ocean) is characterized by many dangerous natural processes. However, due to the low population density of the region, their impact on nature management often goes unnoticed. This sometimes gives a false impression of their lack of strength compared to similar processes in other more populated areas of the world. However, if the population density in the coastal zone of Pacific Russia corresponds to the indicators of Japan or Indonesia, the consequences of their occurrence in most cases would be catastrophic. An inventory of hazardous natural processes in the region was carried out. The intensity of their manifestations in other parts of the world was compared and a division of these processes according to the degree of their danger to the region was made. In the category of the most significant processes, the force of manifestation of which corresponds to the maximum possible values observed on Earth, or is approaching them includes earthquakes, tsunamis, volcanic eruptions, avalanches and cryogenic processes. The second group includes mudflows, aufeises, river erosion, abrasion, landslides, screes, landslides, subsidence and suffosion. The third group (the probability and intensity of which within the coastal zone of Pacific Russia are minimal) includes gully erosion, sheet erosion, rock streams, heaving, shrinkage, karst and aeolian processes. If we compare with other Russian regions, some processes (volcanic eruptions and tsunamis) are distributed exclusively within the coastal zone of Pacific Russia, others (earthquakes, aufeises, abrasion, rock streams, cryogenic processes) have a generally higher intensity, the importance of the third (karst, subsidence, etc.) is obviously lower than in other Russian regions.
Temperature conditions of snow mass and snow melting features in urban environments
Authors: Mikhalev M , Lobkina V
Published: September 2019

The paper presents the features of the snowmelt dynamics of snow mass in the urbanized area in different altitudinal zones, with different regimes of anthropogenic load. The temperature distribution in the snow layer data analysis is carried out. The capabilities of snow mass monitoring system analysis according to the periods of active water loss prediction is carried out.
The invasive plant species in the flora of Sakhalin
Authors: Sabirova N D , Sabirov R N , Lozhnikova O O
Published: September 2019

The article is devoted to the formation of modern composition of the adventive and the invasive component of flora in Sakhalin Island. More effective expansion of the alien plant species was in the 20th century during the colonization and the scale development of the island’s natural recourses. Today there is a new splash of the alien plants drifting due to development of offshore oil and gas projects and intensive traffic flows. As a result, anthropogenic transformations of many years Sakhalin natural landscapes caused the expansion of adventive flora to 240 taxa, where 26 species are the invasive and widespread on the island.
The Antimicrobial Activity and Characterization of the Cast Titanium Copper Alloys with Variations of Copper Content
Authors: Korda Akhmad A. , Munawaroh S. , Basuki Eddy A.
Published: September 2019

The effect of Cu addition on antimicrobial activity of Cast Ti-Cu Alloys against Staphylococcus aureus were studied. The Ti-Cu alloys were prepared with a variation of 0.5, 1, 2, 3, 4, 8 and 10 wt% of copper. Pure Ti metal was also prepared and tested as a comparison. The antibacterial was performed by killing activity test of colony forming unit (CFU) method with variation of contact time. Optical microscope observation, XRD, and the Vickers hardness test were carried out to characterize the investigated alloys. The results showed that Ti-Cu alloys were able to decrease the amount of bacteria by time. However, the activity of killing of bacteria in the varied range of Cu content did not show significantly different result. The highest bacterial kill ability in the alloy was observed in addition of 3 wt% Cu.
Effect of Phenolic Resin on Density, Porosity, Hardness, Thermal Stability, and Friction Performance as A Binder in Non-Asbestos Organic Brake Pad
Authors: Nawangsari P , Jamasri  , Rochardjo H S B
Published: September 2019

Phenolic resin is the most common resin binder used in brake pad materials. Selection of the relative amount of phenolic resin is an important to maintain structurally intact with the other ingredients of brake pad composite. In this experimental study, the effects of phenolic resin as a binder in non-asbestos organic brake pad was investigated. The brake pad composite was made using a powder metallurgy technique. Four formulations with different volume fractions 10, 15, 20, and 25 were selected. Parameters applied were 47 MPa compaction pressure, 150 °C molding temperature, and 130 °C post curing temperature with 6 hours holding time. The properties of brake pad composite were examined density, porosity, hardness, thermal stability, and friction performance (refers to SNI 09-0143-1987). The results show the increase of phenolic resin content can decrease the density, porosity, thermal stability, friction coefficient, and volume wear rate by 1%, 16.79%, 2.39%, 42.5%, 24.16%, respectively. However, the hardness increases by 19.29 %. This investigation also recommends not to select 10 and 15 volume fraction of phenolic resin due to lower resistance to mechanical stresses although the thermal stability is better than the other studied composites.
Study of Strontium Effect on ADC12/Nano-Al2O3 Composite Characteristics with Al-Ti-B Grain Refiner Addition by Stir Casting Method
Authors: Syahrial A Z , Al-Wafiy M
Published: September 2019

Cast iron are the common material used as brake-shoe component of the train, but this material has a high density of 7,25 g/cm3 which tends to be heavy and causes more energy consumption. Aluminum composites can be used as alternative materials with less density. For improving the mechanical characteristic of the aluminum composite, grain modification can be done using strontium (Sr) addition. This research is intended to know the effect of variation of addition of Sr as a modifier on microstructure and mechanical properties of ADC12 composite material with reinforcement of 0,03 vf% nano-Al2O3 particles. Composite fabrication is done by stir casting method. The addition of Mg as wetting agent was 5 wt%, Al-5Ti-B as a grain refiner was 0.04 wt%, and Sr as modified grain with varying addition as much as 0.018; 0.021; 0.026; 0.028; and 0.037 wt%. To characterize the composite product, several testing is done, which is chemical composition characterization, metallographic observation, Scanning Electron Microscopy – Energy Dispersive Spectroscopy characterization, X-Ray Diffraction characterization, hardness testing, wear testing, tensile testing, and impact testing. The results of mentioned testing generally indicate an increase in mechanical properties of the material, due to the role of Sr in the morphological modification of silicon and quasi-binary Mg2Si, secondary dendritic arm spacing size reduction, and wetting agents in the composite system. However, excess addition of Sr will increase the %porosity of the material.
Influence of Tack Weld on Physical and Mechanical Properties of MIG Welding of AA5083H116
Authors: Mudjijana  , Ilman M.N. , Iswanto P.T.
Published: September 2019

The research objective is to determine the effect of tack weld on physical and mechanical properties of tandem-MIG (T-MIG) welding of AA5083H116 materials. A Tenjima 200S MIG machine, sample dimension of 300mm × 75mm × 3mm, and 0.8mm diameter ER5356 electrode were used. The distance between electrodes of T-MIG was varied of 18, 27, 36mm. Welding speed of 12.5mm/s, and welding process was shield using argon gas. First, T-MIG welding were employed for untacked and tacked welding. The leading current was 125A and trailing current was 120A, but current wave of each T-MIG welding machine was not taken into account. The welding voltage was set the same. Second, parameters resulting in better physical and mechanical properties were then employed for single-MIG (S-MIG) tack weld using 8, 10, 12mm/s welding speeds. The result shows that T-MIG tacked weld produced in bowing distortion and T-MIG untack weld in downward bending distortion. Higher peak temperature resulted in larger distortion. T-MIG tacked weld results in welding efficiency 76% being similar with that of bending strength (75%) in comparison with that of as received material. T-MIG tack weld results in better penetration and 37% shorter welding time in comparison with S-MIG tack weld.
Failure Analysis of the Leaf Spring of Truck Colt Diesel Using Finite Element Method
Authors: Husaini  , Riantoni Rizki , Ali Nurdin , Putra Teuku Edisah
Published: September 2019

Damage is often experienced by leaf springs of diesel trucks, known as premature failure and is need to be analyzed. Thus, this study aims to analyze the causes of failure of leaf springs through analytical and numerical analyses. Hardness testing was performed using the Rockwell method. Microstructure was observed using scanning electron microscopy to identify the fracture surface. Analytical and numerical analyses were used to obtain the load distribution of each spring. The analysis results of load distribution on each spring were 26.95 kN. The chemical composition of the specimen shows that the material was tested according to AISI 5150 standard. The hardness value of leaf springs tested was HRB 106.9. The Result of numerical and analytical shows that the strain, stress and deformation of leaf springs with maximum values occurred at the near of hole of spring. The K

I
value ≈ KIC
, therefore this may cause crack propagation. The failure of leaf springs was caused by fatigue during the operation marked by a beach mark and the normal stress is far below the specimen fatigue strength.
Observation on Cetyl Trimethyl Ammonium Bromide Addition as Cationic Surfactant on Water-based Carbon Microfluid Performance for Quench Medium in Heat Treatment Process
Authors: Ramadhani C.A , Putra W.N. , Rakhman D. , Oktavio L. , Harjanto S.
Published: September 2019

Quenching takes an important part in the heat treatment process that controls the microstructure, thus enhance its mechanical properties. The heat treatment process starts with heating at an elevated temperature, holding time then rapid cooling to room temperature. It requires a medium with a good thermal conductivity that can be achieved by the addition of nanoparticles to the quench medium, referred to as nanofluids. In this research, carbon particles were prepared by the top-down method, where the reduction of carbon particle was done by planetary ball-mill for 15 hours at 500 rpm. Cetyl Trimethyl Ammonium Bromide is utilized as a cationic surfactant in order to reduce agglomeration at suspended particles thus increase quenching efficiency. Field-Emission Scanning Electron Microscope (FE-SEM), and Energy Dispersive X-Ray Spectroscopy (EDX) were used to observe the composition of material, particle size and particle morphology, and the change of the surface. Initial characterization by FE-SEM showed that the particle size after milling was averaged roughly at 15 µm, therefore, it was still not in the nanometer range. However, EDS result confirmed that the powder used in this research were 99% carbon. Carbon microparticles were added as the particle to distilled water as the microfluid base. Water-based carbon microfluid with a volume of 100 ml was produced by the two-step method, by mixing carbon microparticles at 0.1 wt%, and 0.5 wt% in various concentration of cationic surfactant of 1 wt%, 3 wt%, and 5wt % respectively. Samples of AISI 1045 or JIS S45C carbon steels were heat treated by austenizing at 1000°C in a heating furnace, followed by rapid quenching in microfluid as the medium quench resulting on cooling rate diagram. Mechanical properties and microstructures of the quenched samples will be observed by conducting hardness examination and metallography observation to analyze the effect of various carbon and surfactant concentration used in the water-based carbon microfluid quench medium.
Effect of Pulse Parameters on The Particle Size of Copper Powder Electrodeposition
Authors: Wahyudi S , Soepriyanto S , Mubarok M Z , Sutarno
Published: September 2019

In this paper, copper powder fabrication has been made via electrolysis method using CuSO4and H2SO4in aqueous media. Electrodeposition process of copper powder on a metallic surface is done by applying to continue current and pulse current with rectangular pulse waveform. Characterization of copper powder was carried out by SEM to confirm particle size and shape and EDX to determine the copper powder composition. In electrodeposition by applying to continue current to produce the copper powder with particle shape was dendritic, and the elemental composition of the powder was Cu and O. Regarding average particle size, pulse electrodeposition process produces the copper powder with average particle size up to 0.85μm, 72.6% smaller than if apply to continue current.
Effect of Gelatin On The Corrosion Resistance Of Cr-ZrO2 Coatings In 3% NaCl Solution
Authors: Setiawan Asep Ridwan , Ramelan Aditianto , Rachmantyo Riska , Luthfiani Febi
Published: September 2019

In this work, Cr-ZrO2 composite coating were prepared by electrodeposition method on aluminium substrate from chromic acid based electrolytes containing gelatin. The effect of gelatin on the corrosion resistance of Cr-ZrO2 coatings were studied in 3 wt.% sodium chloride solutions. Potentiodynamic polarization studies were performed using a Versastat 3 (Princeton Applied Research) electrochemical system with a three-electrode cell. Results shows that the corrosion resistance of Cr-ZrO2 coating on Al substrate was improved by the addition of gelatin to the coating solution. The addition of gelatin shifted the potentiodynamic polarization curved in the noble direction. The corrosion potential changed positively from -778 mV to -259 mV. The corrosion rate of Cr-ZrO2 coating decreased from 4.44±0.93 mpy to 0.13±0.01 mpy with the addition of 3g/L gelatin.
Fabrication of Cr based electrodeposited composite film using nano ZrO2 particles on aluminum substrate
Authors: Sato Kota , Sugio Kenjiro , Choi Yongbum , Sasaki Gen , Setiawan Asep Ridwan , Ramelan Aditianto
Published: September 2019

In this study, the coating method suitable for producing high-quality film on aluminum substrate was investigated by using different surface treatment to each specimen before electrodeposition. Microstructure of coating cross section was observed with Electron Prove Micro Analyzer (EPMA). Vickers hardness of coating surface was measured. The measurement of polarization behavior of aluminum in CrO3-H2SO4 electrolyte with ZrO2 addition was carried out to investigate corrosion resistance. The addition of ZrO2 particles increased Vickers hardness of Cr coating. The existence of Zr in the coating was confirmed by point analysis from coating cross section. Polarization point was shifted higher by dispersing ZrO2 particles into the plating bath, and this means that corrosion resistance was improved by the addition of ZrO2 particles.
Physical Aging of Zr65Cu17.5Ni10Al7.5 Glassy Alloy
Authors: Aji Daisman P.B. , Triyono  , Mujalis Yusep
Published: September 2019

Physical aging of Zr65Cu17.5Ni10Al7.5 glassy alloy has been studied after holding its samples with variation of time and temperature of annealing. The results showed that the enthalpy and entropy decreased with time according to a non-exponential kinetics. The Differential Scanning Calorimetry (DSC) heating scan after annealing was analyzed using Tool-Narayanaswamy-Moynihan (TNM) model. The analysis showed that a set of parameters that fitted the heating scan data for one annealing time did not fit the heating scan data for another annealing time. This is explained due to approximations used in the model and the effect of Johari-Goldstein (JG) relaxation to the physical aging.
Effect of Sodium Nitrate-Sodium Fluoride Ratio as Degasser in Al-7Si-2Cu Casting Product
Authors: Dhaneswara Donanta , Fatriansyah Jaka Fajar , Hanandhira Naila , Basa Agatha Rona , Reza Firmansyah M.
Published: September 2019

Effect of Sodium Nitrate-Sodium Fluoride Ratio as degasser in Al-7Si-2Cu Casting product has been investigated. Degassing is one of the methods used in the casting process to remove gases, such as hydrogen gases, in the molten metal. The most commonly used degassing method is by injecting an inert gas such as argon. In this experiment, a conventional degassing method with degasser-based sodium nitrate-sodium fluoride was used with changes in sodium nitrate to sodium fluoride ratio variables are 3:5, 4:4, and 5:3. The type of material used is Al-7Si-2Cu material with additional scrap. The material melted first at 800°C, then the degasser was added into the furnace and held for 3 minutes. High temperature was used to melt the material due to the solubility of hydrogen gases in liquid metal at high temperature is high. The molten metal then poured into the dies at approximately 690°C. The casting process results are then prepared for mechanical testing, such as tensile test, impact test, and hardness test, and microstructure testing. The results show that at the ratio of 1:1.5 (normal ratio), the porosity was lower (0.8 at average) and the mechanical strength was higher (1.2 at average).
Development of Steel Matrix Composites Used for Metal Die
Authors: Sasaki Gen
Published: September 2019

In this study, we show the development of the steel matrix composites used for metal die. Matrix used is 40CrMoV5 (ISO standard) steel, which is used as press and die-casting dies. The dispersants used are vapor grown carbon nanofiber (VGCF), which is one of carbon nanofiber (CNF) and titanium die-bride (TiB2) particle powder. After mixing 40CrMoV5 powder and the dispersants by ball milling, the composites was prepared by spark plasma sintering (SPS) process. For VGCF, 1.9 and 3.8 vol. % was added to 40CrMoV5 powder in order to obtain the composites. The thermal conductivity of the VGCF/40CrMoV5 alloy composites improved about 20% compared with the 40CrMoV5 monolithic alloy. The tensile strength of the composites with 1.9 vol. % VGCF is about 1980MPa, which is higher than the monolithic alloy with 1250 MPa. For TiB2 particle, 4.0, 8.0 20.0 vol. % powders was added to 40CrMoV5 powder. By adding 8.0 vol. % TiB2, the thermal conductivity improved about 40% compared with the monolithic alloy, but tensile strength decreased to 612 MPa in 8.0 vol. % VGCF composites, which are caused by the aggregation of TiB2 powders. It seems the strength of the composites will improve by controlling the dispersibility of TiB2 powders.
The Effect of Service Time on Carbide Volume Fraction and Hardness of Catalyst Tube Materials
Authors: Bastian Maulidin , Sugiharto Eko , Ardy Husaini
Published: September 2019

The effect of service time on secondary carbides formation in reformer furnace tubes has been studied to obtain a relationship between carbide volume fraction, service time, and hardness. Tube material is Kubota KHR35CT which is part of ASTM A297 HP class. The study was performed by examinations of microstructural evolution and hardness. The microstructures were examined using optical and scanning electron microscopes of the new tube, and the other tubes that had been in service for 17,500; 96,300 and 113,800 hours at 850°C. Carbide volume fraction was measured using image analyzer. Carbide volume fraction of the new tube is 7.72%, and increased to 8.86% after 17,500 hours, 9.54% after 96,300 hours, and 10.95% after 113,800 hours. The increase in carbide volume fraction to 8.86 % did not affect the hardness substantially because the hardness only increases from 191 to 198 BHN. However, increasing exposure times to 96,300 and 113,800 hours decreased the hardness to 170 and 173 BHN respectively. These decreases in hardness may be corresponding to the coarsening and agglomeration of carbide particles due to longer exposure time at 850°C.
Preparation of Nanocellulose-Alginate Nanocomposites for Chlorhexidine Digluconate Drug Carrier
Authors: Evelyna Angela , Astifanni Tiara Khumaira , Ruth Imelda , Asri Lia , Purwasasmita Bambang Sunendar
Published: September 2019

Root canal treatment failures generally caused by microorganisms that have ability to invade dentinal tubules. Chlorhexidine is widely known to effectively eradicate broad spectrum bacteria that infected dentinal tubules. The delivery of chlorhexidine to the infected site of root canal still becomes an issue. In order to increase the stability and to regulate the release of chlorhexidine, encapsulation of chlorhexidine digluconate was conducted by employing nanocellulose and alginate nanocomposites. Nanocellulose was prepared from palm kernel cake using acid hydrolysis method. Transmission electron microscopy images showed the formation of whisker and fiber nanocellulose with the average diameter of 20 nm. Resulting nanocellulose was combined with alginate in the presence of Ca2+ crosslinker. Scanning electron microscopy images displayed sphere and oval morphologies of microcapsules with diameter of 500 nm. The microcapsules were further loaded with chlorhexidine digluconate 2% (w/v). In vitro drug release properties were evaluated in PBS at pH 7.4 (normal tooth environment) and at pH 5.5 (infected tooth environment). The UV-VIS results showed that chlorhexidine digluconate has higher release rate at pH 5.5 than at pH 7.4, suggesting that the microcapsule is a good candidate for the delivery of chlorhexidine digluconate to the infected root canal tooth environment.
Elastic Modulus Determination of Thermoplastic Polymers with Pulse-Echo Method Ultrasonic Testing
Authors: Judawisastra Hermawan , Claudia  , Sasmita Firmansyah , Agung P Toni
Published: September 2019

The determination of the elastic modulus of the structural thermoplastic polymers is especially required during in-service monitoring of the components. This elasticity modulus determination can simplify the inspection process and predict the lifetime of the polymer being used. The elastic modulus of the polymer can be determined by pulse-echo method testing ultrasonic which is easier to use than transmission method. This research aims to determine elastic modulus of thermoplastic polymers i.e. polymethylmethaacrylate (acrylic), polyamide (nylon) and low density polyethylene (LDPE) calculated from measurement of velocity and attenuation of ultrasonic pulse-echo. The research begins by looking at the effect of the use of three different probes to ultrasonic velocity readings. Then elastic modulus of material polymers from ultrasonic velocity was calculated using standard equation. The elastic modulus was compared with the elastic modulus from mechanical testing. A linear model elastic modulus from ultrasonic reading which consists of velocity and apparent attenuation was developed. The results were elastic modulus value obtained from ultrasonic velocity and standard equation had a profound error 98% to 158%, especially for polymer with an eminently low density and high ratio of viscous property to elastic property. The attenuation from ultrasonic reading was influenced by the viscoelastic properties and the elastic modulus from ultrasonic velocity reading was influenced by the density. A linear model for thermoplastic elastic modulus determination based on ultrasonic pulse echo testing has been developed and could reduced the error to 3.45%.
Preparation Of Superhydrophobic Zinc Oxide Nanorods Coating On Stainless Steel Via Chemical Bath Deposition
Authors: Nuruddin Ahmad , Yuliarto Brian , Kurniasih Santi , Setiyanto Henry , Ramelan Aditianto
Published: September 2019

The stearic acid modified zinc oxide nanorod surface was coated with a stainless steel substrate to improve the contact angle and the sliding angle. Facilitated through ZnO seeding on the substrate, the ZnO nanorod was deposited via chemical bath deposition at different precursor concentrations. The surface hydrophobicity was modified by varying concentrations of stearic acid at and submmersion time. The contact angle was investigated in relation to the surface microstructure and modification. Results indicate that the density of ZnO nanorods on the substrate surface and stearic acid coverage are prerequisites for improving surface hydrophobicity. Superhydrophobic properties with a contact angle of 162° was obtained for ZnO deposited with 35 mM zinc nitrate and submerged in 8 mM stearic acid for 36 h, which allowed 5 μL water droplets to slide at 3.8°.
Advancement In Forward Osmosis (FO) Membrane For Concentration Of Liquid Foods
Authors: Handojo L.A. , Khoiruddin K. , Wardani A.K. , Hakim A.N. , Wenten I G.
Published: September 2019

In food processing, concentration of liquid food is one of the important steps required for several purposes. Concentration of liquid food while preserving sensorial and nutritional components is quite challenging, especially for thermal-based concentrating processes. This is due to the significant loss of those components which are heat sensitive. Therefore, considerable efforts have been devoted to develop new concentrating processes which can solve this problem. Among the developed processes, forward osmosis (FO) has been considered as an interesting alternative since it can be operated at low operating pressure and temperature and obtain a concentrated solution with high solid contents. However, there are several challenges in FO operation e.g. fouling phenomena, concentration polarization, and reverse diffusion of solution from draw solution. To address these issues, several developments have been made to prepare membrane which has high hydrophilicity, low fouling tendency, reduced concentration polarization, and low solute diffusion. The desired membrane has been obtained, for example, by modifying selective and support layers of the membrane. This paper reviews advances in FO membrane, including membrane preparation and modification. Principle and important parameters of FO in concentrating liquid foods are overviewed. In addition, challenges and strategies in FO membrane preparation are discussed.
Hydrophilic Modification of Polymeric Membrane using Graft Polymerization Method: A Mini Review
Authors: Pinem J.A. , Wardani A.K. , Aryanti P.T.P. , Khoiruddin K. , Wenten I G.
Published: September 2019

The separation performance of polymeric membrane is strongly influenced by its surface characteristics. In water treatment applications, it is generally accepted that a hydrophilic membrane surface is favorable to enhance water permeate flux and mitigate membrane fouling. Numerous methods, both chemical and physical modification, have been proposed to improve the hydrophilicity of polymeric membranes. Graft polymerization is one of the promising methods to modify polymer membranes by tethering hydrophilic polymer chains onto membrane surface. The existence of hydrophilic chains on the membrane surface facilitates the reduction of interfacial tension with water, thus higher water flux can be obtained. In addition, the increase of membrane hydrophilicity also improves the antifouling resistance. This review provides a concise summary and discussion of the modification of polymeric membranes using graft polymerization method. The effects of graft polymerization on the membrane hydrophilicity as well as the antifouling property are discussed.
Effect Of Silicon On Corrosion Behaviour Of Al-Zn As A Low Voltage Sacrificial Anode For Marine Environment
Authors: Pratesa Yudha , Utama Ahmad A. , Erianto Ardi , Ferdian Deni
Published: September 2019

A sacrificial anode is a method for material protection in the sea and coastal area. This method is widely applied in marine, subsea and ship structure. Al-Zn-In, a commercial grade of the sacrificial anode had a weakness in the possibility of stress corrosion cracking due to overprotection. This study tried to substitute indium with silicon as the alloying element with composition 0.5% and 1% wt. However, commercial grade Al ingot contained trace elements such as iron in the significant amount, which could make a β-Al9Fe2Si2 as an iron-rich intermetallic phase. Therefore, this study will also examine the effect of β-Al9Fe2Si2 on alloys corrosion behavior. The alloy was produced through casting process with resistance furnace. Corrosion behavior was characterized by cyclic polarization in 3.5% NaCl solution. Microstructure characterization was performed using Scanning Electron Microscope, Energy Dispersive Spectroscopy, and optical metallography. The result showed that the silicon increases the corrosion rate of Aluminum Zinc (Al-Zn) and reduced the potential protection of the alloy in high strength steel. Our research showed the corrosion took place along the interdendritic area where the β-Al9Fe2Si2 intermetallic phase formed in a micro galvanic manner
Effect of 5-15% Carbon Black Reinforcement on Mechanical Properties and Resistivity of Polyurethane Composites
Authors: Rahmalina Dwi , Irwanto Jefri , Sukma Hendri , Susanto  , Setiawan Indra C. , Suhadi Amin
Published: September 2019

This research investigated the effects of carbon black-reinforced thermoplastic polyurethane matrix composite with variation of 5, 10, and 15 vol.% on mechanical properties and electrical resistance. The composites were produced using injection molding process with temperature of 193 °C, pressure of 30 bar and injection speed of 176 mm/sec. Characterization of composites were conducted by hardness and tensile testing, electrical resistivity measurement and SEM examinations. The results showed that the highest tensile strength of composite of 20.44 MPa is obtained with carbon black 10 vol.% reinforcement. The hardness improved with the increase of carbon black reinforcement, which the highest hardness was produced on carbon black 15 vol.% composite by 89.5 Shore A. The lowest resistivity was achieved in polyurethane composite reinforced with 15 vol.% carbon black of 8.20 x 105 Ω.
Thermal Behaviour Studies on Building Walls based on Type and Composition of the Materials
Authors: Andoni Heri , Jurizat Aldissain , Steven  , Thomas Dixon , Achsani Rizky Amalia , Sutjahja Inge Magdalena , Mardiyati  , Wonorahardjo Surjamanto
Published: September 2019

Controlling the thermal behaviour of buildings is very important because it affects the energy use in the buildings and impacts the thermal environment of the area. Thermal behaviour of the building is determined by the type and composition of the building material. This paper shows the thermal behaviour of several types and composition of commonly used building wall materials, i.e. brick, aerated concrete, laminated wood with glass wool insulation, and gypsum with glass wool insulation. For the thermal behaviour measurements, we used wall models exposed to halogen lamps of 2000 watts for 4 hours heating and 4 hours for cooling with a measurement interval of 5-15 minutes. Data retrieval using 8 thermocouples mounted on the surface and inserted inside the wall. The observed thermal behaviour phenomena are the heat flow on the walls, the time delay, and the heat capacity. The results show different maps of the thermal behaviour on the walls and indicating the need for additional thermal insulation material to control the heat release to the outside and inside of the building.
Effect of heat treatment on the stress corrosion cracking (scc) susceptibiliy of the 13Cr martensitic stainless steel for steam turbine blade
Authors: Rusnaldy  , Mabruri Efendi , Nugroho Luky W.
Published: September 2019

Two different constant loads have been used to evaluate the effect of heat treatment on susceptibility to stress corrosion cracking (SCC) of 13 Cr martensitic stainless steel in 3.5% NaCl. The steel specimens were austenitized at 1050°C for 1 hour followed by oil quench to obtain martensite structure. Then, specimens were tempered at 400, 500, 600, 650 and 700°C for 1 hour. To investigate the SCC susceptibility, SCC tests were carried out at two different constant loads of 40% and 80% of ultimate tensile strength (UTS) in accordance with the method developed by Nishimura et.al. After the SCC tests, scanning electron microscope (SEM) observations of the fracture surface on the fractured specimens were conducted to investigate fracture mode. The experimental results showed that the 13Cr martensitic stainless steel was highly susceptible to SCC in a solution 3.5% NaCl at high constant load (80% of UTS) in almost tempered conditions. The least susceptible steel was the tempered one at 700°C. At lower constant load (40% of UTS), the highly susceptible steels were the tempered ones at 400 and 500°C. Steels which were tempered at high tempering temperature were not failed for 240 hours of SCC testing. The mechanism responsible for this susceptibility is thought to be secondary phenomenon where carbide precipitation of M7C or M23C6 occurs. The fracture surfaces exhibited intergranular cracks and dimple rupture fracture for steels tempered at 400, 600 and 650°C and transgranular cracks and cleavage fracture for steels tempered at 500°C.
The Preparation of Electrical Double Layer Capacitor (EDLC) from Boron-doped Reduced-Graphene Oxide (B-rGO) Material
Authors: Susanti Diah , Andrameda Yurian Ariandi , Nurdiansah Haniffudin , Purwaningsih Hariyati , Pradesar Yusuf , Ardhyananta Hosta
Published: September 2019

The increase of human needs to electronic instruments requires sufficient energy storage devices. One of the electrochemistry-based energy storage devices is electrochemical capacitor (EC). The challenge in EC manufacturing is to prepare ECs with high energy and power densities. It depends very much on the ECs material. In this research, graphene, theoretically a single layer of carbon material, was used as the material for electrical double layer capacitor (EDLC), a type of ECs. To enhance the electrical conductivity, graphene was doped with boron using 1 M H3BO3 (boric acid) with volume variations of 1, 2, and 3 ml. X-Ray Diffractometer (XRD) and Scanning Electron Microscope (SEM) equipped with Energy Dispersive X-Ray Spectroscopy (EDXS) were used to characterize the structure, morphology and element content of the material. Four Point Probe (FPP) method was used to measure the materials electrical conductivity, while Cyclic Voltammetry (CV) measurement was used to inspect the capacitive properties of the material in 1 M Na2SO4 electrolyte solution. The best result, 192.5 F/g, was found from B-doped graphene with 2 ml volume of boric acid (equivalent to 4.37 %B). From this experiment, boron doping significantly improved the capacitive properties of graphene-based EDLC.
Detection and Quantification of FLT3 Internal Tandem Duplication Mutations Do Not Vary Significantly Between Whole Blood and Blast-Enriched Samples
Authors: Schumacher Jonathan A , Holgard Victoria D , Sial Faryal , Pearson Lauren N , Patel Jay L , Karner Kristin H
Published: September 2019

Objectives

Many commonly used FLT3 mutational assay protocols require a tedious blast enrichment step. We investigated whether elimination of this step would still give equivalent results and compared the accuracy of variant allele fraction (VAF) between polymerase chain reaction/capillary electrophoresis (PCR/CE) vs next-generation sequencing (NGS) methods.

Methods

Total leukocyte vs blast-enriched whole-blood aliquots were tested for FLT3 internal tandem duplication (ITD) and tyrosine kinase domain mutations by PCR/CE. VAF of the ITD mutations was also compared with NGS VAF.

Results

Blast-enriched vs total leukocyte specimens showed 100% concordance in the 25 positive specimens. VAF was consistently lower by NGS, with poorer fidelity to PCR/CE VAF as the ITD size increased.

Conclusions

Our study supports elimination of the blast enrichment step without compromising results or sensitivity. In addition, since NGS shows a loose correlation with PCR/CE quantitative results, NGS VAF should not be reported for FLT3 ITDs.
The Many Faces of Cardiac Sarcoidosis
Authors: Serei Virian D , Fyfe Billie
Published: September 2019

Objectives

The objective of this study was to review and illustrate the sometimes diagnostically challenging features of cardiac sarcoidosis. We emphasize variable phenotypes presented at explant and biopsy evaluation and review literature regarding ancillary clinical and pathologic studies to enhance diagnostic accuracy.

Methods

A literature review was performed and two cardiac sarcoidosis cases were illustrated.

Results

Our cases and literature review demonstrate the pathologic spectrum of cardiac sarcoidosis. Irregular left ventricular free wall involvement is most common, followed by the interventricular septum and right ventricle. Although granulomas are often composed of tight epithelioid macrophage aggregates, early granulomas comprise loosely associated macrophages with lymphocyte predominance. Chronic disease leads to fibrosis and end-stage heart failure. Sampling errors and variable histology cause low endomyocardial biopsy sensitivity.

Conclusions

Current guidelines use clinical, radiologic, and immunohistologic criteria for diagnosing cardiac sarcoidosis. Knowledge of these guidelines will assist pathologists in making accurate diagnosis of this disease.
The Cluelessness Objection Revisited
Authors: Yim Lok Lam
Published: September 2019

Lenman (2000)'s cluelessness objection against consequentialism states that we are almost entirely clueless to the actual consequences of our action. In ‘Cluelessness,’ Hilary Greaves (2016) distinguishes between ‘simple’ and ‘complex’ cases of cluelessness and argues that the principle of indifference applies to ‘simple’ cases, thereby rescuing the ‘simple’ cases from the cluelessness objection. In this discussion note, I argue that Greaves's distinction between ‘simple’ and ‘complex’ cases fails and cluelessness is more problematic than Greaves believes.