bluuebunny/crossref_metadata_2025 huggingface dataset:
New life for old wires: electrochemical sensor method for neural implants
Authors: Weltin Andreas , Ganatra Dev , König Kathrin , Joseph Kevin , Hofmann Ulrich G , Urban Gerald A , Kieninger Jochen
Published: October 2019

Objective. Electrochemical microsensors based on noble metals can give essential information on their microenvironment with high spatio-temporal resolution. However, most advanced chemo- and biosensors lack the long-term stability for physiological monitoring of brain tissue beyond an acute application. Noble metal electrodes are widely used as neural interfaces, particularly for stimulating in the central nervous system. Our goal was to recruit already deployed, unmodified noble metal electrodes (Pt, Pt/Ir) as in situ chemical sensors. Approach. With advanced electrochemical sensor methods, we investigated electrode surface processes, oxidizable species and oxygen as an indicator for tissue mass transport. We developed a unique, multi-step, amperometric/potentiometric sensing procedure derived from the investigation of Pt surface processes by chronocoulometry providing fundamental characterization of the electrode itself. Main results. The resulting electrochemical protocol preconditions the electrode, measures oxidizable and reducible species, and the open circuit potential (OCP). A linear, stable sensor performance was demonstrated, also in the presence of proteins, validating signal stability of our cyclic protocol in complex environments. We investigated our sensor protocol with microelectrodes on custom Pt/Ir-wire tetrodes by in vivo measurements in the rat brain for up to four weeks. Results showed that catalytic activity of the electrode is lost over time, but our protocol is repeatedly able to both quantify and restore electrode sensitivity in vivo. Significance. Our approach is highly relevant because it can be applied to any existing Pt electrode. Current methods to assess the brain/electrode microenvironment mainly rely on imaging techniques, histology and analysis of explanted devices, which are often end-point methods. Our procedure delivers online and time-transient information on the chemical microenvironment directly at the electrode/tissue interface of neural implants, gives new insight into the charge transfer processes, and delivers information on the state of the electrode itself addressing long-term electrode degradation.
Integrated plasma scenario analysis for the HL-2M tokamak
Authors: Xue L. , Garcia J. , Zheng G.Y. , Hoang G.T. , Artaud J.F. , Duan X.R. , Li J.X. , Giruzzi G. , Zou X.L. , Pan W. , Zhang J.H. , Huang M. , Wei H.L. , Bai X.Y. , Ji X.Q. , Song X.M. , Wang S. , Song X. , Xue M. , Huang W.Y.
Published: October 2019

HL-2M is a new medium-sized tokamak under construction at the Southwestern Institute of Physics, dedicated to supporting the critical physics and engineering issues of ITER and CFETR. Analyzing integrated plasma scenarios is essential for assessing performance metrics and foreseeing physics as well as the envisaged experiments of HL-2M. This paper comprehensively presents the kind of expected discharge regimes (conventional inductive (baseline), hybrid and steady-state) of HL-2M based on the integrated suite of codes METIS. The simulation results show that the central electron temperature of the baseline regime can achieve more than 10 keV by injecting 27 MW of heating power with a plasma current of I
p  =  3 MA and Greenwald fraction f 
G  =  0.65, with the thermal energy and β
N reaching 5 MJ and 2.5, respectively. The hybrid regime with f 
ni  =  80%–90% can be realized at I
p  =  1–1.4 MA with f 
G around 0.5, where β
N is 2.3–2.5 with H
98(y ,2)  =  1.1. Because of the effect of the on-axis NBCD, the hybrid steady state, at I
p  =  1.0 and 1.2, can be achieved more easily than the steady state regimes with reversed shear, corresponding to β
N  =  2.6 and 3.4. Such studies show that HL-2M is a flexible tokamak with a significant capacity for generating a broad variety of plasmas as a consequence of the different heating and current drive systems installed.
Survival and Reproductive Value of Hermetia illucens (Diptera: Stratiomyidae) on Vegetable and Fruits Waste Rearing Substrate
Authors: Julita U , Fitri L L , Putra R E , Permana A D
Published: October 2019

Hermetia illucens, black soldier fly has been a topic of interest in the ecological research world for many years especially in terms of its role as a bioconverter agent. Bioconversion process through black soldier fly represents a potential valuable solution to two problems: organic waste management on the one hand and on the other, the rising global demand for animal feed (transform organic waste into valuable animal feedstuff in the form of their last larval stage or prepupa). In this context, the aim of this study is to assess the survival and reproductive value of black soldier fly reared on vegetable and fruits waste. All treatments were constructed under laboratory conditions at 26±1°C temperature and 68%±0.5% relative humidity. The adult cage was placed near the window that allows sunlight to enter. Data were collected and analyzed based on an age-stage, two-sex life table. The intrinsic rates of increase (r) were 0.06877 and 0.05772 per days, finite rate of increase (λ) were 1.0712 and 1.0594 per days, net reproduction rate (R0) were 25.88 and 19.99 offspring, and mean generation time (T) were 46.403 and 50.00 days on vegetable and fruits waste, respectively. Our results demonstrated high mortality in the larval period that probably caused by high levels of water produced by vegetables and fruits waste during the experiments.
Constraints on Dark Energy Models in Cosmology from Double-Source Plane Strong Lensing System
Authors: Jaelani Anton T , A P Emas Ni Putu , Premadi Premana W , M Mulki Fargiza A
Published: October 2019

We performed an investigation of the possibility of constraining the dark energy models such as w-cold dark matter, holographic dark energy, and Ricci dark energy, using a special type of Einstein ring system, called as double-source plane (DSP) lensing system. We found that DSP lensing system only gives a good constraint of the model parameters. We also found that the method highly complimentary to cosmic microwave background measurement for each model.
Possibility of C/2002 CE10 in state of retrograde-polar resonance with Saturn in the future
Authors: Pangestu Ayu Dyah , Dermawan Budi
Published: October 2019

Many objects in the Solar System which are associated or in resonance state with the giant planets have low orbital inclination. The effect of resonance that occurs on high-inclination objects is not well-known. This study describes results of numerical studies in term of orbital evolution of a high inclination Halley-Type Comet C/2002 CE10 (LINEAR). The ephemeris data was taken from JPL Small Body Database (https://ssd.jpl.nasa.gov/sbdb_query.cgix) at the epoch of MJD 58200. We report that C/2002 CE10 (LINEAR), whose inclination is 145°, will be in a retrograde 1:-1 (co-orbital - trisectrix type) resonance with Saturn for about 600 thousand years in the future. This resonance state is examined using the method FAIR (Fast Identification of Mean Motion Resonance). C/2002 CE10 (LINEAR) exhibits chaotic orbits and may not be stable in the resonance state. While data quality of the provided orbital elements is not quite good, orbital evolutions of clones of C/2002 CE10 (LINEAR) show small possibility that the object will be in the resonance state (retrograde co-orbital) with Saturn in the future.
Three-Dimensional Modeling of Multiphase Fluid Flow With Linear Temperature Gradients In Porous Media Using Lattice Boltzmann Method Rothman-Keller
Authors: Pradana B , Fauzi U
Published: October 2019

In oil and gas production, only about 5% to 20% of hydrocarbons can be released through production wells with natural reservoir pressure. In the oil and gas industry, there is a method called enhanced oil recovery (EOR) to remove hydrocarbons trapped in rock pores. EOR is not easy and expensive, so fluid flow modeling and simulation are required to reduce the cost. In fluid modeling, there is a continuous approach using the Navier-Stokes (NS) equation. Not only the continuous approach, but fluid modeling also can be done by using Molecular Dynamics (MD) approach. Between these two methods, there is a method that bridging the advantages between the two. This method uses a macroscopic and microscopic approach (mesoscale) called Lattice Boltzmann Method (LBM). With this approach, the results obtained are quite accurate without the use of high computing devices. The LBM used in this research is the Rothman-Keller (RK) / color gradient method. This method assumes that the interaction force between two fluids is directly proportional to the two-fluid density ratio and has two collision operators, BGKW operator, and perturbation operator. This method is then subjected to pressure on the boundary region introduced by Zou-He. Then the temperature is given linearly and be used to calculate body force due to the temperature gradient. This study shows that the model that has been made is successfully simulating the flow of multiphase fluid in rock pores. In the model viscosity as a function of the temperature found that the average velocity of the fluid flow decreases when the temperature increase. In the temperature gradient model, when the temperature gradient increases, the average velocity, and saturation of the wetting fluid increases.
Tracing Galactic Arm with 6614 Å Diffuse Interstellar Band and Gaia DR2 Distances
Authors: Puspitarini L , Lallement R
Published: October 2019

Enigmatic problem in astronomical spectroscopy is diffuse interstellar bands (DIBs). DIBs are ∼ 500 weak and broad absorption features seen in the spectra of stars or other astronomical objects located behind interstellar materials. Despite the unknown ions or molecules that caused the absorptions, except for two near infrared DIBs, DIBs can be used as a potential interstellar medium (ISM) tracer to map Galactic structure. Gaia is a mission of the European Space Agency (ESA) which was launched on 2013. It provides precise distances which greatly improve our knowledge of the structure and history of our Galaxy. In this work, we used previously determined DIB equivalent width (EW) measurements by means of DIB fitting that is a combination of a synthetic stellar spectrum, a synthetic telluric transmission, and empirical DIB profile to the Gaia–ESO Large Public Spectroscopic Survey data. From DIB measurements from stellar spectra of distributed target stars and together with Gaia DR2 distances, we investigated the ISM distribution along particular line of sight, i.e., (l,b)∼(213°, -2°) which probes Local and Perseus Arm.
Measurement of The Night Sky Brightness in e-Maya Observatory
Authors: Harijadi Noor Laksmiyanti Annake , Herdiwijaya Dhani , Wibowo Ari
Published: October 2019

One of the ideal criteria for an observatory is the location that is related to its influence on the condition of the night sky. The observatory area is a light pollution-free area, far from the city or urban center. This is intended to get a dark night environment so the observations can be done well. The e-Maya Observatory is one of the observatories in Indonesia that located in Subang, West Java. Established in 2013, the observatory’s work is relatively new in Astronomy field in Indonesia. This observatory was built in the area of Astha Hannas Subang High School which is about 18 km to the north from the center of Subang city. To find out the quality of the night sky and how big the impact of city lighting or the level of light pollution in the e-Maya Observatory area, it is necessary to measure the brightness of the night sky. Measurement of the night sky brightness used a simple sky brightness photometer, Sky Quality Meter (SQM), there are two SQM types used, SQM LU and SQM LU-DL. SQM measures the brightness value of the night sky in magnitude per squared arcseconds (mag/arc sec2) all night on August 11-14, 2018 towards the east and west horizons with the slope angle of 30° (z = 60°) and pointed to zenith (z = 0°).
Primary Productivity of Blanakan Fishpond at Subang, West Java
Authors: Takarina Noverita Dian , Runtuwene Desi Octavia
Published: October 2019

Subang regency is one of the largest fisheries area in West Java, so it is important to maintain the quality of fishpond area in Blanakan, Subang. Primary productivity can be defined as the production rate of organic carbon per unit time which is the result of solar energy by green plants to be converted into chemical energy through photosynthesis. Primary productivity can be used to define the quality of an ecosystem including fishpond. The aim of this research was to measure the value of primary productivity in mangrove fishpond, determine the correlation between the primary productivity and the content of nitrate, phosphate, and chlorophyll-a, and to analyse the significance primary productivity differences among three sampling stations. The samples were collected from three sampling stations, where all of those consist of mangrove Avicennia marina vegetation. Each station was divided into two points based on different depth i.e. 0 and 1,5 meters. The measurement of primary productivity was done by light-dark bottle method, meanwhile the nitrate, phosphate and chlorophyll-a concentration by spectrophotometer method. The result showed that the value of primary productivity ranged from 39.0625 to 101.5625 mgC/m3/day with the highest value obtained at station I and the lowest value at station III. According to statistical test, there were a significant differences of primary productivity value among three sampling stations with the value is 0.003 (p < 0.05). Correlation analysis showed that primary productivity was correlated positively with chloropyll-a and negatively with nitrate and phosphate contain water.
Antibacterial activity of ZnO nanoparticles fabricated using laser ablation in solution technique
Authors: Yudasari Nurfina , Wiguna Pradita A. , Suliyanti Maria M. , Imawan Cuk
Published: October 2019

The zinc oxide (ZnO) nanoparticles have been produced by using laser ablation in solution technique, resulting nanoparticles with hexagonal wurtzite structure and the size range of 20 – 50 nm. The optical characterization has predicted the nanoparticles band gap at least 3.16 eV. The ZnO nanoparticles were employed as an antibacterial agent for the growth of Escherichia coli (E. coli), and it shows a great potential. Total plate count (TPC) analysis was conducted by applying the ZnO nanoparticles with different concentration of 5%, 10%, 15%, 20%, 25% and 30% (portion of bacteria medium). The 5% concentration could reduce more than half of the E. coli population after 24 hours incubation time. There was no living bacteria detected for 20%, 25% and 30% ZnO concentration.
The Role of MgO as Swelling Cements Admixtures under CO2 Attack on API Class-G Cement
Authors: Palilu Juniarto M , Soegijono Bambang , H Marbun Bonar T
Published: October 2019

API Class-G Portland cement commonly put in as zonal isolation material in oil and/or gas well. Corrosion against the well zonal isolation material could lead to potential leakage of formation fluid such oil, gas, or water. It is widely known that ordinary Portland cement is thermodinamically unstable in CO2 rich environment, which can be found in the CO2 geological sequestration. CO2 attack on API Class-G cement had been observed through experiments that simulate the down hole condition of Geological Sequestration of CO2. Some of the experiment reveal the detrimental effect of CO2 such as increase of porosity and permeability of cement sheath corroded by CO2 attack. The degradation of API Class-G cement by CO2 involves emergence and crystallization of CaCO3 from Ca(OH)2 which is formed during hydration of cement. In this experiment, we examine the role of addition of MgO swelling cement by weight fraction to mitigate the corrosion caused by CO2 against downhole hardened API Class-G cement thus inhibits the occurrence of leakage path of CO2. Observation for characterization and analysis by XRD, optical microscope, and cement paste uniaxial volumetric expansion presented in this paper. The conclusion will provide insights into design of carbonation resistant cement slurries using swelling cements admixtures.
Aitken’s Generalized Least Square Method for Estimating Parameter of Demand Function of Animal Protein In Indonesia
Authors: Virgantari Fitria , Wijayanti Hagni , Koeshendrajana Sonny
Published: October 2019

Ordinary least square (OLS) method is the most popular and commonly technique used to estimate numerical values of parameters of selected regression models. This was due to its unbiasedness property. However, when elements of dependent variable have unequal variances and/or correlated each other, there is no guarantee that the OLS estimator will show the most efficient within the class of linear unbiased estimators. For conditions generally encountered, GLS method is proposed an estimation procedure which yields coefficient estimators at least asymptotically more efficient than single equation OLS estimator. This method is derived by Aitken and it’s named Aitken GLS. This paper reported a study of application of Aitken’s GLS method for estimating parameter of demand function of animal protein in Indonesia of which have a system equation. This system of equation causes violation of the assumptions of homoscedasticity and independency of estimated parameters. Secondary data obtained from the Central Bureau of Statistics 2016 in 34 provinces in Indonesia was used in this study. Animal food was grouped in terms of fish, meat, eggs and milk. Results showed that error of those three equations were correlated. It suggests that GLS method should be used. Normality and homogenity assumptions were not violated. The determination coefficient was 99%, indicating that the method was very good.
Introducing Fermat Sequences
Authors: Wibowo R W
Published: October 2019

This paper focuses on simple observation of Fermat’s factorization method (FFM) applied on the first 5 × 106 odd number. The number of iteration used in the FFM is related to the factor that the method found for each odd number. A new collection of sequences or sets of numbers (we called it Fermat-d sequences) can be generated based on the factor that we found using this method. For example, the first member (Fermat-1) in this collection of sequences is odd prime number sequence, which has factor–of course–of 1 and has highest number of iteration in the FFM, which is ∼half of the number itself. The next member of these sequences (Fermat-3, Fermat-5, and so on) are always start from d
2, continue with arithmetic progression of 2d, but, with additional ‘random jumps’ related to the prime number distribution. We present the first exploration of these new sequences (not registered in oeis.org yet) and the beauty of the location of these sequences in the Ulams and Sacks spiral.
Introduction of Emaya Observatory
Authors: Wibowo A
Published: October 2019

Located at the coordinates of 107°47′39″BT and -6°24′15″ LS maked Emaya Observatory as an observatory that closed to the center of astronomical studies in Indonesia, Bosscha and the astronomy faculty at ITB, as well as Jakarta which known as the first Planetarium in Indonesia. This observatory can facilitate access for education and training in improving the performance of observatory technicians. It was very well aware that the observatory that established was a private observatory which would require an injection of knowledge and motivation. Because this observatory was not managed from who had astronomical background. So that it required hard work, so that the observatory can still function properly. The Emaya Observatory was established in 2013 which at the beginning was only aimed at providing servants for the executors of rukyatulhilal only, where this was in line with the founder’s future goals to participate in the development of the Indonesian Nation and establish harmony between people of Indonesia. He believes that by providing a place for rukyathilal, it can provide servitude to people and state. Aside from rukyatulhilal activities, other research activities are also carried out, namely photometry by optimizing the equipment that was currently owned which was a Telescope with a ZWO 120MM camera and DSLR. Also activities in astronomy teaching and training for school institutions both students and teachers who are members of the Science and Physics MGMP, Hisab and Rukayatul training for Islamic organizations or foundations in collaboration with the Subang Ministry of Religion and the Province also provide services in measuring Qibla direction.
The Influence of Humid Atmosphere during the MAPbI3 Perovskite Layer Preparation on the Characteristics of Its Solar Cells
Authors: Nurunnizar Adhita Asma , Hidayat Rahmat
Published: October 2019

Organometal halide perovskite (hybrid perovskite) materials have emerged as a promising material for high power conversion efficiency and low-cost solar cells. The formation of organo-metal halide perovskite layer, however, is very sensitive to some process parameters such as concentration, temperature, and humidity. In this study, we report the preparation of CH3NH3PbI3 (MAPbI3) perovskite crystal layers under a relatively humid air atmosphere and investigated the characteristics of their solar cells with both mesoporous cell structure and planar cell structure. Due to high humidity, we found that the formed layer tends to form a shiny grey to black color layer on the top of the dark brown color perovskite layer. This layer showed poor x-ray diffraction (XRD) pattern and caused poor solar cell performance. The formation of this layer, however, can be prevented by anti-solvent treatment during the preparation of perovskite layer.
A Preliminary result on the rGO functionalization as counter-electrode in dye-sensitized solar cells (DSSC)
Authors: Arsyad Waode Sukmawati , Wardianto Ahmad , Variani Visca Inda , Ilmawati Waode Sitti , Agusu La , Hidayat Rahmat
Published: October 2019

In the effort of replacing Platinum (Pt) based counter-electrode (CE) for reducing fabrication cost in the dye-sensitized solar cell (DSSC), we synthesized rGO powder from graphite bar (commercially available) using modified Hummer’s method with an introduction of microwave irradiation. rGO was attached to the FTO surface by dissolving it in the solvent with the addition of ethyl cellulose (ES) following by two-step annealing process. rGO solution was deposited by spin coating technique with different thickness namely 1 layer rGO (A1), 5 layer rGO (A2), 10 layer rGO (A3) and 15 layer rGO (A4) followed by an annealing process, and the reference cell was assigned as A5 (using Pt). From the thin film resistance measurement using the four-probe method and conductivity calculation, the conductivity decreased as the rGO layer becomes thicker, namely from (0.58 to 0.42, 0.07 and 0.03) S/cm for A1, A2, A3, and A4 in consecutive order. From the photovoltaic measurement, we found that the utilization of rGO as a catalyst in CE increased the efficiency of the cell from 3.82% (A5) to 4.52% (A1). Furthermore, increasing the thickness of rGO layer from A1 (2.1 μm) to A2 (10.5 μm) also increased the efficiency from 4.52% to 5.89%, further increasing on the layer thickness A3 (21 μm) to A4 (31.5 μm) reduced the conversion efficiency to 2.57% and 0.33%. The highest conversion efficiency achieved for the cell with 10.5 μm thickness of CE, specifically A2. Further investigation of the influence of CE thickness and conductivity to the internal parameters of the DSSC must be done in order to gain a much better understanding of this result.
Fast forward of adiabatic spin dynamics : An application to quantum annealing model in triangle spin systems.
Authors: Setiawan Iwan , Gunara Bobby Eka , Nakamura Katsuhiro
Published: October 2019

We propose a scheme of the fast forward of adiabatic spin dynamics in a triangular 3 spin cluster of quantum annealing model and reveal the structure and role of driving pair-wise interaction and three-body interactions. We settle the quasi-adiabatic spin dynamics (QASD) by adding the regularization terms to the original Hamiltonian and accelerate it with use of a large time-scaling factor which realizes QASD on shortened time scale. Assuming the candidate regularization Hamiltonian consisting of three-body interactions besides the pair-wise exchange interactions and magnetic field, we solved the regularization terms. These terms multiplied by the velocity function give rise to the state-dependent counter-diabatic terms (CDTs) for each of adiabatic states. Applying this method to quantum annealing model, we find CDTs which include pair-wise interaction and the 3-body interactions. The driving pairwise and three-body interaction in the fast-forward scheme guarantees the complete fidelity of accelerated states.
Photoproductions of K+Λ and K0Λ Studied by Using Isobar Model
Authors: Clymton S , Mart T
Published: October 2019

We have investigated the neutral kaon photoproduction off a neutron by using an isobar model based on our previous study. The unknown parameters were extracted by fitting the model prediction to experimental data. We analyzed the two Λ channels, i.e., K
+Λ and K
0Λ channels, simultaneously. We used two different approaches in the fitting process which lead to two different models. We compare the agreement between model prediction and experimental data for both models quantitatively. The result reveals the effect of including the K
0Λ data on the model and thus improves our understanding on the kaon photoproduction process.
Spectral Analysis of Volume Operators in Loop Quantum Gravity for Kinematical Case
Authors: Sebastian Ignatius , Husin Idrus , Ariwahjoedi Seramika , Zen Freddy P.
Published: October 2019

Loop Quantum Gravity has become one of the alternative solutions to quantum gravity. This formulation introduced geometrical operators which successfully used to model that in the quantum scale, the space is actually discretized in the order of Planck length. These operators are area and volume operator. The regularization process of these operators came from the classical definition of area and volume, thus, the eigenvalues of area operator and volume operator are respectively the area and volume of the space. However, there exists two types of volume operator, the Ashtekar-Lewandowski operator and the Rovelli-Smolin operator. The significant difference between these two operators is the fact that Ashtekar-Lewandowski operator is sensitive to the direction of the spin networks link, while Rovelli-Smolin operator is not. This difference will produce different spectral. In this article, we compare the resulting spectral of the two volume operators, where both of them is used to calculate the volume of the monochromatic 4-valent and 6-valent spin network for the kinematical case.
The experimental investigation on the crystalline structure, lattice vibration, and optical energy of La1-xBixFeO3 nanoparticles
Authors: Fitria S N , Triyono D
Published: October 2019

Lanthanum-bismuth orthoferrite (La1-xBixFeO3 with x=0.1, 0.2, 0.3, 0.4 and 0.5) nanoparticles have been successfully prepared using sol-gel method. The crystalline structure, lattice vibration, and optical energy analysis have been characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman scattering spectroscopy, and UV-Vis spectroscopy. The XRD revealed the single phase orthorhombic structure with Pnma space group. The crystallite size tends to decrease in the range of 130 – 298 nm with increasing Bicontent. The existence of Fe–O strectching and bending modes were investigated by FTIR spectra and also confirmed by Raman scattering analysis. The optical bandgap was investigated by UV-Vis spectroscopy concluding the decrease of gap energy with Bi-content.
Triangular inequality for 3d Euclidean simplicial complex in loop quantum gravity
Authors: Husin Idrus , Sebastian Ignatius , Ariwahjoedi Seramika , Zen Freddy P.
Published: October 2019

Triangular inequality is an important relation in geometry such that this relation, intuitively, is a statement that the direct line connecting two points is the shortest one. Loop quantum gravity is presented after a reformulation of gravity using Ashtekar variables. The quantization follows the Dirac procedures, which results in the existence of state of quanta of 3d space as an element of Hilbert space. Spin network states has become the basis state for quanta of space in loop quantum gravity. In loop quantum gravity space is discrete and the geometrical quantity is quantized at the Planck scale. In 3d space, we can define triangular discretization of the hypersurface. In this article we discuss the length spectrum and check whether the triangular inequality is satisfied by the quantum length. The answer to the question is positive, such that even at the Planck scale the triangular inequality is still valid.
Capabilities of non-medicamentous sympathocorrection of the tone of cerebral veins in people with accelerated ageing
Authors: Yakimova M E , Gavrilova M N , Polozova O V , Zimina I S , Mukhina S A
Published: October 2019

The article studies the effectiveness of the electroimpulse sympathocorrector influence on the area of the cervical sympathetic ganglia in patients with early signs of ageing. Using the ultrasound angiography method, we found that the course of sympathocorrection normalizes the diameter of internal jugular veins and contributes to improvement of cerebral venous outflow. In its turn, this implies that the development of angiodystonic changes, arterial hypertension and atherosclerosis in the organism are decelerated. The method of percutaneous electroimpulse actions in the area of the cervical sympathetic ganglia can be recommended as a way to prevent premature and accelerated ageing in the blood circulatory system and as an additional method in complex therapy.
Detectability of flat microdefects in radiographic images obtained using linear microfocus bremsstrahlung source based on 18 MeV betatron with narrow target inside
Authors: Rychkov M M , Kaplin V V , Smolyanskii V A
Published: October 2019

For the determination of ability of microfocus Bremsstrahlung (Bs) source based on B-18 betatron to detect flat microgaps and microinclusions in heavy material products the investigations were carried out. The radiographic images of 10 μm gaps and 13 μ m tantalum (Ta) foil into steel bulk which were oriented at different angles with respect to the direction of radiation were investigated. The assembly of four steel blocks having 10 μm gaps between their neighbor surfaces was placed on goniometer. The 13 μm Ta foil having the length of 4 mm along radiation beam was mounted in a plastic holder which was also placed on the goniometer. For modeling narrow gaps and thin inclusions inside the bulk of steel detail, the experimental samples were placed before a thick steel plate. The radiographic images of the samples were obtained with a 2.4-fold magnification at different orientations of narrow gaps and Ta foil with respect to the radiation beam and at the thick steel plates of different thicknesses. The results illustrate high sensitivity of detecting of the microgaps inside steel bulk and flat microinclusions from heavy material in the bulk of detail made from a lighter material due to the microfocus of Bs source.
Specific features of diagnostic of wellhead equipment and gas field pipelines at the stage of declining production
Authors: Balina O V , Nassonov V V
Published: October 2019

The paper presents the results of studies of climatic factors impact on the processes of aging and degradation of materials of field equipment in the Subpolar climatic zone. On the basis of diagnostic measures and analysis of dispatching data on daily pressure fluctuations in pipelines, ambient temperature variations, frequency of wind gusts and amount of precipitation the damage probabilities of the pipeline linear section and wellhead equipment due to various factors have been determined.
Hardware-software system for magnetic analysis of structure
Authors: Kostin V , Vasilenko O , Byzov A
Published: October 2019

The relative values of the magnetic properties of a substance is shown to be determined locally by measuring the magnetic field induction in the transducer hole of a special form made in the magnetic circuit of the measuring transducer and the tangential component of the magnetic field in the interpolar transducer space near the surface of the magnetized object.The proposed method is shown to allow for the determination of the whole complex of hysteresis characteristics and significantly expand the ranges of measurement of magnetic properties.The difference in the structural sensitivity of the magnetic properties locally determined in the coordinates “flow-internal field” (properties of matter) and in the coordinates “flow in the product-current in the windings” (properties of the “body”) is established.The possibility and expediency of simultaneous measurement and pooled analysis of the magnetic characteristics of the substance and the “body” is shown.Information about the mobile hardware-software system DIUS-1.15M, designed to implement one-and multi-parameter methods of monitoring the structural-phase and stress-strain state of ferromagnetic materials and objects based on the proposed measurement techniques is provided.
Study of the effect of ultrasound scanner settings on the level of radiation intensity by the reciprocity method
Authors: Bogdan O P , Muravieva O V , Gulyaeva Yu S , Shirobokova A D
Published: October 2019

In this paper, a new method of measuring the intensity on the radiating surface of the convex sensor of the ultrasonic diagnostic scanner EDAN U50 with its various settings was proposed, based on the reciprocity method using a hydrophone calibrated with a vibration simulator. The effect of the following scanner settings on the peak-spatial average time-averaged intensity in B-mode was experimentally investigated: ultrasonic radiation frequencies, number of focuses, and number of focus positions. It was found that changing the scanner settings significantly changes the temporal parameters of the emitted bursts of pulses, which affects the result of averaging intensity over time. At the same time, an increase in the number of focuses leads to a decrease in intensity, while an increase in the focus of the positions and frequency of the radiation, on the contrary, leads to its growth. Studies have shown that the intensity value exceeds the allowable values at almost any settings of the ultrasound scanner, with the exception of the ultrasound frequency of 2.5 MHz.
Control of defects in layer composite materials by the method of electromagnetic emission
Authors: Borovikov A K , Luchnikov P A , Podgorny Yu V , Frolova O A , Chernova N I
Published: October 2019

The article considers the method of non-destructive quality control of layered composite materials based on registration and spectral analysis of electromagnetic radiation of piezoactive adhesive joint and cavitation acoustic noise. The method allows the diagnostics of adhesive compound defects of layer composite materials with 50 [%] accuracy and 0.7 confidence level. The spectrum of electromagnetic radiation of the adhesive compound shows defects at the layered boundary. The use of active piezoelectric layer of elastomer adhesive joint increases adhesion strength at stratification by 2.1 – 5.2.
The research of the quality of ECG recording by capacitive electrodes in violation of the skin-electrode contact
Authors: Boyakhchyan A A , Ivanov M A , Morenetz A I , Pavlenko B N , Torgaev S N , Lezhnina I A
Published: October 2019

This paper presents actual development in the field of personal telemedicine. For personal cardiographs most suitable dry electrodes that do not require a conductive gel. This article describes experiments with capacitive electrodes from Plessey Semiconductors. On the basis of the obtained experimental data, it is planned to create own capacitive electrodes with the possibility of detuning from the skin-electrode contact.
Temperature regulator for containers with working substance in high-frequency metal vapor active media
Authors: Bukreev E G , Kozhemyak O A , Musorov I S , Ogorodnikov D N , Drobchik V V
Published: October 2019

This paper presents the study of the control functions for the temperature control of containers with the active substance in active media on metal vapors. Nonlinear control function was built and tested with a layout of container. Tests demonstrate discordant, but primary positive results of using nonlinear regulator instead of linear proportional-integral-differential (PID) regulator.
Hierarchy of calibrated global models reveals improved distributions and fluxes of biogeochemical tracers in models with explicit representation of iron
Authors: Yao Wanxuan , Kvale Karin F , Achterberg Eric , Koeve Wolfgang , Oschlies Andreas
Published: October 2019

Iron is represented in biogeochemical ocean models by a variety of structurally different approaches employing generally poorly constrained empirical parameterizations. Increasing the structural complexity of iron modules also increases computational costs and introduces additional uncertainties, with as yet unclear benefits. In order to demonstrate the benefits of explicitly representing iron, we calibrate a hierarchy of iron modules and evaluate the remaining model-data misfit. The first module includes a complex iron cycle with major processes resolved explicitly, the second module applies iron limitation in primary production using prescribed monthly iron concentration fields, and the third module does not explicitly include iron effects at all. All three modules are embedded into the same circulation model. Models are calibrated against global data sets of NO3, PO4 and O2 applying a state-of-the-art multi-variable constraint parameter optimization. The model with fully resolved iron cycle is marginally (up to 4.8%) better at representing global distributions of NO3, PO4 and O2 compared to models with implicit or absent parameterizations of iron. We also found a slow down of global surface nutrient cycling by about 30% and a shift of productivity from the tropics to temperate regions for the explicit iron module. The explicit iron model also reduces the otherwise overestimated volume of suboxic waters, yielding results closer to observations.
Aloe Vera as A Coating Material for Tropical Fruits Using Spray Method
Authors: Darmawati E , Nava N , Suyatma N E
Published: October 2019

Aloe vera is one of the coating materials that has begun to be widely studied. The application of spray method in fruit coating requires the formulation of a solution to generate droplets that are small, smooth and can forms a film. The purpose of this research was to study the characteristics of the film and droplet produced by various concentrations of aloe vera solution applied by spray method. Observation variables for selection of the best concentration included droplet diameter, film thickness, and Water Vapor Transmission Rate (WVTR). Solution with 10% aloe vera resulted in droplet diameter of 0.26 mm, while at a concentration of 20% yielded a droplet diameter of 0.37 mm. The thickness of the film produced from both- concentrations were 0.9 mm. The WVTR value was not significantly different, i.e 3.02 g/m2- day and 3.03 g/m2-day for the concentration 10% and 20%, respectivaly. The application of 10% aloe vera coating using spray method on rambutan of Lebak varieties decreased respiration rate from 15.08 ml O2/kg-hour to 5.77 ml O2/kg-hour at 10° C storage temperature. Based on these result, the selected formula of coating using spray method was 10% aloe vera solution.
Effect of Hormone Treatment, Coating Material and Ethylene Absorber on the Shelf Life of Mangosteen
Authors: Herawati H , Winarti C , Setyabudi D A , Wahyuningsih K
Published: October 2019

Several factors affect the shelf life of mangosteen fruit, such as the low quality of fruit at harvest time or poor storage and transportation precise conditions before the fruit is consumed. Cause of poor quality of mangosteen fruit for export due to hardening of fruit skin after harvest and harvesting through matures caused by the lack of proper handling of harvest and postharvest. The objective of the research was to study the effect of hormone treatment, coating material and ethylene absorber to the shelf life of mangosteen. Treatments were implemented by coating process using a combination of GA3 hormone treatment and coating materials (chitosan and wax). The other treatments used were combination of plastic and teabag packaging containing KMNO4. The study was designed using a completely randomized design. Observations included external visuals, internal visuals, weight loss, color, texture, and skin structure. The data analysis was performed using SPSS 2.1 software. At first week, the condition of treated mangosteen fruit were still resembles with fruit on day-0. This was due to the cooling factor, assisting in the process of maintaining the freshness of the mangosteen fruit.
Chemical Identification of Coconut Shell Liquid Smoke
Authors: Mulyawanti I , Kailaku S I , Syah A N A , Risfaheri
Published: October 2019

Coconut shell liquid smoke is produced from a chemical pyrolysis process that involved smoke bearing water vapor from burning coconut shells in very high temperature. Materials used in this study were coconut shell liquid smoke with three different grades. Visually, grade 1 liquid smoke was clear. Grade 2 liquid smoke was reddish in color and not as clear as grade 1, while grade 3 was dark brown. This difference may indicate that each grade had different chemical compositions. The aim of this study was to identify the chemical compounds of the three different grades of coconut shell liquid smoke using Gas Chromatography-Mass Spectroscopy (GC-MS). Extraction was carried out using Head Space Solid Phase Micro Extraction (HS-SPME). Result showed that the coconut shell liquid smoke contains high content of polyphenol. Polycyclic Aromatic Hydrocarbons (PAHs) including benzo(a)pyrene were also found. The findings of this study may be useful as basis in the determination of the application of the different grades of coconut shell liquid smoke.
Curing Process Modification of Shallot Through Cutting Leaves
Authors: Amiarsi Dwi , Sasmitaloka K S , Arif A B , Widayanti S M
Published: October 2019

Shallot (Allium cepa L. Var. ascalonicum Backer) is one of horticulture crop that serves as a spice in daily cuisine for almost all Indonesian people. One of postharvest handling of shallot after harvesting is the curing process to extend the freshness of shallot bulbs. Curing process needs a lot of energy to dry the leaves. Even though the curing process only to dry the bulbs. For this reason, we can cut the leaves through a curing process to save the energy. This study aimed to obtain the right cutting leaves to save energy needed in the curing process. T he shallot bulbs are harvested in the morning. Then the shallot leaves are cut to the length of each leaf 1-10; 11-20; 21-30 cm and without cutting (as a control). The results showed that the cutting technique of shallot leaves with a leaf length of 1-10 cm to 11-20 cm from the initial leaf length could shorter until 4 days curing processing time with a weight loss of 16.22%, water content of 80.83%, the brightness value of 45.60, and the texture of 1589.00 grams/mm2.
Simple extraction of silica nanoparticles from rice husk using technical grade solvent: effect of volume and concentration
Authors: Setyawan N , Hoerudin  , Wulanawati A
Published: October 2019

One of the main components of rice husk ash (RHA) is silica, which can be used as raw material for fertilizer. The study examined influences of various volume and concentration on silica extraction. The silica was extracted using a technical alkaline grade solvent (NaOH) with a variation in volume/the ratio of RHA to the amount of solvents (1: 4, 1: 5, and 1: 6) and the solvent concentration (0.50, 0.75 and 1 N). The highest average yield was found in the concentration of 1 N solvent with the ratio of RHA to the number of solvents 1: 6 is 62.83%. Based on the physical characteristics of silica from RHA which include whiteness (93.2496.66%), moisture content (0.49-2.81%), and density (0.56-0.95 g / mL) indicates that the use of technical alkaline solvents tends to decrease the purity of the proven silica also with the presence of major contaminants such as Na and Cl and other elements through SEM-EDX, XRF, and XRD test. In saline soils, the presence of contaminants in silica with an amorphous phase (2θ = 22.29°) especially Na and Cl may have a negative effect if used as raw material for fertilizers.
Effect of Arrowroot Nano Starch Preparation Methods on the Characteristics of Temulawak Oleoresin Microcapsules
Authors: Winarti C , Richana N , Mangunwidjaja D , Sunarti T C
Published: October 2019

Active compounds of temulawak often have some disadvantages such as barely dissolve in water, unstable in alkaline and acidic conditions, that need to be overcome by coating with the starch matrix. Starch nanoparticles precipitated with alcohol can serve as coating material because it has a helical hole and the porous structure. The research objective was to determine the effect of starch nanoparticles coating materials on the characteristics of temulawak microcapsule. The treatments tested included types of coating/starch matrix resulted from two different preparations of arrowroot starch nanoparticles namely by butanol and ethanol precipitation with two degrees of hydrolysis. The parameters observed consist of yield, encapsulation efficiency (EE), drug loading (DL), morphology (SEM and TEM), particle size distribution and polydispersity index (PDI), FTIR, and antioxidant activity. The results showed that the yield of microcapsules ranged from 42.91 to 58.31%, with EE from 48.69 to 69.59% and DL from 19.02 to 28.96%. Microcapsule size ranged from micro to nano size having 200 nm in average with rounded shape, and polydispersity index from 0.69 to 0.94. The antioxidant activity showed that microcapsule coated with butanol precipitation starch matrix was higher than that of ethanol precipitation. The FTIR analysis showed a binding of the active ingredient (curcumin) in the matrix as seen with the new absorption peak at a wavelength of 1510 cm−1 as well as two new peaks at 1750 cm−1 and 3730 cm−1.
The Effect of Air-Drying on Yield of Essential Oil from Sereh Wangi Plants Cultivated on Degraded Land
Authors: Achmad E , Mursalin  , Novra A
Published: October 2019

Citronella (Cymbopogon nardus L) is a kind of plant producing essential oil. The cultivation does not require special requirements, can be grown on less fertile soil, and able to rehabilitate degraded and critical lands. In this study, 5 levels of drying duration (0, 1, 2, 3, and 4 days) were observed for their effect on the yield of citronella oil grown at 3 critical levels of land (quite critical, critical, and very critical). The experiment was designed in a completely randomized block design with 3 replications. The distillation of whole citronella leaves was carried out for 4 hours using steam distillation method. The result showed that the air drying significantly affected the yield of citronella oil. An increase in drying duration decreased the yield of oil in a linear trend. The highest yield of oil was produced from fresh raw material (0 days drying duration). The decrease of the oil yield due to the increase of drying duration at three levels of critical land (quite critical, critical, and very critical) followed the equation Y1 = - 0.024x + 0.711; Y2 = -0.017x + 0.704; and Y3 = -0.012x + 0.704 (for y = yield [%] and x = drying duration [day]).