bluuebunny/crossref_metadata_2025 huggingface dataset:
Near-infrared photoresponse in Ge/Si quantum dots enhanced by localized surface plasmons supported by aluminum nanodisks
Authors: Yakimov A. I. , Kirienko V. V. , Bloshkin A. A. , Dvurechenskii A. V. , Utkin D. E.
Published: October 2020

An array of plasmonic nanoparticles can sustain surface plasmon modes from visible to infrared spectral range and thus offers effective surface light trapping, enhancement of local fields, and interaction with the thin active regions of optical devices. We report the fabrication and optical characterization of a planar Ge/Si quantum dot (QD) detector grown on silicon-on-insulator (SOI) substrate for photodetection in the near-infrared telecommunication wavelength range. The multilayer Ge/Si QD heterostructures are near-field coupled to the adjacent layers of aluminum nanodisks on the detector top. The periodic Al disk arrays have the square lattice symmetry with a lattice constant of 400 nm and the disk diameter varying from 150 to 225 nm. A significant enhancement in the room-temperature detector sensitivity is achieved due to the excitation of localized surface plasmons supported by the metallic disks and radiative coupling to the SOI waveguide modes. Through extinction spectroscopy and numerical modeling, we confirm the emergence of nanoparticle-induced plasmon resonances near the Si–Al interface. We demonstrate that an appropriate choice of the array periodicity and the size of the metal disks is able to increase the photodetector's efficiency by ∼ 40× at λ=1.2μm and by 15× at λ≈1.55μm relative to a bare detector with no plasmonic structure. These outcomes pave the way toward the use of Al as a low-cost plasmonic material with potential applications in infrared photodetection similar to those of the noble metals.
Subsonic and supersonic nucleus-acoustic solitary waves in thermally degenerate multi-nucleus plasma systems
Authors: Mamun A. A.
Published: October 2020

A new thermally degenerate multi-nucleus plasma system (containing thermally degenerate electron species, non-degenerate warm light nucleus species, and low dense stationary heavy nucleus species) is considered. The basic features of arbitrary amplitude subsonic and supersonic solitary waves associated with thermally degenerate pressure-driven nucleus-acoustic waves in such a plasma system are studied by the pseudo-potential approach. The effects of the stationary heavy nucleus, non- and ultra-relativistically degenerate electron degeneracies, and light nucleus temperature on such arbitrary amplitude subsonic and supersonic solitary waves are also examined. It is found that (i) the presence of the heavy nucleus and Boltzmann distributed electron species supports the existence of subsonic solitary waves and the effects of electron degeneracies and light nucleus temperature reduce the possibility for the formation of these subsonic solitary waves; (ii) the amplitude (width) of these subsonic solitary waves increases (decreases) with the increase in the number density of the heavy nucleus species; (iii) the amplitude of the supersonic solitary waves in the situation of non-relativistically degenerate electron species is much smaller than that of the ultra-relativistically degenerate electron species but is much larger than that of the Boltzmann distributed electron species; (iv) their width in the situation of non-relativistically degenerate electron species is much wider than that of the ultra-relativistically degenerate electron species; and (v) their amplitude (width) decreases (increases) with the increase in the light nucleus temperature. The applications of the results in some degenerate astrophysical plasma systems and non-degenerate space plasma environments are discussed.
Achieving large zeta-potentials with charged porous surfaces
Authors: Vinogradova Olga I. , Silkina Elena F. , Bag Naren , Asmolov Evgeny S.
Published: October 2020

We discuss an electro-osmotic flow near charged porous coatings of a finite hydrodynamic permeability, impregnated with an outer electrolyte solution. It is shown that their electrokinetic (zeta) potential is generally augmented compared to the surface electrostatic potential, thanks to a large liquid slip at their surface emerging due to an electro-osmotic flow in the enriched by counter-ion porous films. The inner flow shows a very rich behavior controlled by the volume charge density of the coating, its Brinkman length, and the concentration of added salt. Interestingly, even for a relatively small Brinkman length, the zeta-potential can, in some cases, become huge, providing a very fast outer flow in the bulk electrolyte. When the Brinkman length is large enough, the zeta-potential could be extremely high, even at practically vanishing surface potential. To describe the slip velocity in a simple manner, we introduce a concept of an electro-osmotic slip length and demonstrate that the latter is always defined by the hydrodynamic permeability of the porous film and also, depending on the regime, either by its volume charge density or by the salt concentration. These results provide a framework for the rational design of porous coatings to enhance electrokinetic phenomena, and for tuning their properties by adjusting bulk electrolyte concentrations, with direct applications in microfluidics.
Influential factors and optimization analysis of adsorption refrigeration system performance
Authors: Zhang Xueling , Wang Feifei , Lei Xudong , Wang Yanling , Zhang Qi , Wu Xuehong , Jin Tingxiang , Wang Yujing
Published: October 2020

This paper reviews recent research on adsorption refrigeration systems. Common and new-type adsorbent–adsorbate working pairs for adsorption refrigeration are summarized and classified. The performance evaluating parameters such as the coefficient of performance and specific cooling power are analyzed for an adsorption refrigeration system, and the influential factors of adsorption refrigeration system performance are investigated from the adsorbent and adsorption bed, respectively. The factors from the adsorbent include the following: the adsorbent particle size, size of micropores inside the adsorbent, total porosity of the adsorbent, and adsorbent stability. Optimization methods for improving adsorbents’ stability are proposed, and four preparation methods for composite adsorbents are summarized. Methods for improving the performance of an adsorption refrigeration system from the adsorption bed are illustrated by examples, including increasing the heat exchange area, improving the surface coating technology, utilizing the heat pipe technology, and designing the multiple adsorption bed system. Among these factors, the working pairs of adsorption refrigeration play the most important role for the system performance, and developing the new type of composite adsorbent to improve the performance and stability is the effective strategy to optimize the system performance. This article also provides suggestions on recent progress and the innovation directions for an adsorption refrigeration system.
Sea surface height trends in the southern hemisphere oceans simulated by the Brazilian Earth System Model under RCP4.5 and RCP8.5 scenarios
Authors: Giarolla Emanuel , Veiga Sandro F. , Nobre Paulo , Silva Manoel B. , Capistrano Vinicius B. , Callegare Andyara O.
Published: October 2020

The Brazilian Earth System Model (BESM-OA2.5), while simulating the historical period proposed by the fifth phase of the Coupled Model Intercomparison Project (CMIP5), detects an increasing trend in the sea surface height (SSH) on the southern hemisphere oceans relative to that of the pre-industrial era. The increasing trend is accentuated in the CMIP5 RCP4.5 and RCP8.5 future scenarios with higher concentrations of greenhouse gases in the atmosphere. This study sheds light on the sources of such trends in these regions. The results suggest an association with the thermal expansion of the oceans in the upper 700 m due to a gradual warming inflicted by those future scenarios. BESM-OA2.5 presents a surface height increase of 0.11 m in the historical period of 1850–2005. Concerning future projections, BESM-OA2.5 projects SSH increases of 0.14 and 0.23 m (relative to the historical 2005 value) for RCP4.5 and RCP8.5, respectively, by the end of 2100. These increases are predominantly in a band of latitude within 35–60°S in the Atlantic and Indian oceans. The reproducibility of the trend signal detected in the BESM-OA2.5 simulations is confirmed by the results of three other CMIP5 models.
Academic and institutional 'one health' research capacity building.
Authors: Oura Christopher , Conlon Kathryn C. , Smith Woutrina , Stephen Craig , Blakley Barry , Saint-Charles Johanne , Clarke Michael
Published: October 2020

This chapter discusses how academia is approaching building transdisciplinary research programmes to promote human, animal and environmental health, based on some generalizable lessons and practical experiences.
One health in policy development: options to prevent rabies in cattle in Bhutan.
Authors: Rinchen Sangay , Tenzin Tenzin , Gurung Ratna B. , Rinzin Karma , Cork Susan
Published: October 2020

This chapter describes the complex issue of handling rabies cases in cattle in Bhutan and illustrates the value of taking a cross-sectoral One Health approach to developing policy options.
A level-set approach based on reaction–diffusion equation applied to inversion problems in acoustic wave propagation
Authors: Lanznaster D L , de Castro P B , Emmendoerfer H , Mendonça P T R , Silva E C N , Fancello E A
Published: October 2020

In this work, a topology optimization procedure based on the level-set method is applied to the solution of inverse problems for acoustic wave propagation in the time-domain. In this class of inverse problems the presence of obstacles in a background medium must be identified. Obstacles and background are defined by means of a level-set function that evolves by following the solution of a reaction–diffusion equation. Within this approach, no initial guess for the topology nor level-set reinitialization procedures are necessary, contrary to what is commonly observed when the Hamilton–Jacobi equation is used. The objective function is defined as the domain and time integration of the squared difference between experimental and simulation pressure signals. The finite element method is used for the spatial and level-set function discretizations and a time-marching procedure (Newmark scheme) is used to solve the wave propagation problem, as well as the adjoint problem for the sensitivity analysis. Both procedures provide the information needed to define the velocity field for the level set evolution. Results show that the proposed technique is capable to find the location and shape of obstacles within a background medium. Systematic tests show that, as expected, the distribution of sources and receivers shows to have a major influence on the final solution. Results also reproduce known difficulties; when the so called inverse crime is avoided, the identification procedure worsens its performance. Filters and smoothing are among different features that deserve further investigation. Although the formulation presented here focuses on the acoustic wave propagation problem, its extension to wave propagation in elastic media is straightforward.
Effect of local strain energy to predict accurate phase diagram of III–V pseudobinary systems: case of Ga(As,Sb) and (In,Ga)As
Authors: Han Gyuseung , Yeu In Won , Park Jaehong , Ye Kun Hee , Lee Seung-Cheol , Hwang Cheol Seong , Choi Jung-Hae
Published: October 2020

This work proposes an efficient and accurate methodology of ab initio thermodynamics to predict phase diagrams of III–V pseudobinary systems. The innumerable configurations of solid solutions are efficiently considered while maintaining accuracy by calculating the energies of freely relaxed configurations with the combined methodology using density functional theory calculations and cluster expansion. Then, the thermodynamic properties are calculated following a grand canonical ensemble framework that takes into account the local compositional fluctuation. The local strain energy induced by this local compositional fluctuation is found to be independent of the configuration; hence, it is calculated separately and added to the energy of a freely relaxed configuration, which significantly reduces the computational cost. This novel methodology is applied to calculate the phase diagrams of Ga(As,Sb) and (In,Ga)As, showing a good agreement with previous experimental reports. Notably, the strain energy is indispensable to predict phase diagrams accurately. It implies both the validity and the applicability of this method to other III–V pseudobinary systems. From an understanding of the crucial role of the strain energy in phase separation, an intuitive prediction is suggested through a simple estimation of the strain energy using the ratio of lattice parameters between various III–V semiconductor materials.
Characteristics of plasma parameters and turbulence in the isotope-mixing and the non-mixing states in hydrogen–deuterium mixture plasmas in the large helical device
Authors: Ida K. , Yoshinuma M. , Tanaka K. , Nakata M. , Kobayashi T. , Fujiwara Y. , Sakamoto R. , Motojima G. , Masuzaki S.
Published: October 2020

Characteristics of plasma parameters and turbulence in the isotope-mixing and the non-mixing states in hydrogen-deuterium mixture plasmas in the large helical device are discussed. The isotope mixing state is characterized by the uniform isotope ratio profile regardless of the location of the particle source of each species in the isotope mixture plasma. The isotope non-mixing state is identified by the non-uniform isotope ratio profile measured with bulk charge exchange spectroscopy when the beam fueling isotope species differs from the recycling isotope species. The effect of collisionality,

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ratio, sign of density gradient on transition between isotope mixing and non-mixing is discussed. The plasma parameters preferable for the non-mixing state are found to be lower collisionality, higher

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, and negative or zero density gradient (peaked or flat density profile). The time scale of transition from non-mixing to mixing is evaluated by the hydrogen and deuterium pellet injection near the plasma edge and is found to be less than 5 ms, which is much shorter than the particle confinement time. The strong correlation between isotope mixing and turbulence characteristics is observed. This strong correlation suggests the change in turbulence is a strong candidate for the mechanism causing the transition between uniform and non-uniform isotope density ratio profiles.
Simultaneous reduction of graphene oxide (GO) and formation of rGO/Gly-Gly composite for sensitive detection of Cu2+ ions
Authors: Sayyad Pasha W. , Shaikh Zeeshan A. , Ingle Nikesh N. , Al-Gahouari Theeazen , Mahadik Manasi M. , Bodkhe Gajanan A. , Shirsat Sumedh M. , Shirsat Mahendra D.
Published: October 2020

Here, we report the sensitive detection of copper (Cu2+) ions using field-effect transistor (FET) based on reduced graphene oxide/glycylglycine (rGO/Gly-Gly) composite. The simultaneous reduction of graphene oxide (GO) using glycylglycine, and formation of rGO/Gly-Gly confirmed by employing X-ray diffraction (XRD), Ultraviolet–visible (UV-vis) spectroscopy, and fourier-transform infrared spectroscopy(FTIR). The formation of rGO/Gly-Gly composite was confirmed by FTIR spectroscopy. Further, the sensing channel was fabricated with rGO/Gly-Gly and explored for the electrical detection of Cu2+ ions between the concentration range of 100 ppb to 600 ppb. Present study recommends that rGO/Gly-Gly are encouraging for low-cost, portable, and real-time detectionof heavy metal ion sensors.
Wet chemical synthesis and investigations of structural and dielectric properties of BaTiO3 nanoparticles
Authors: More S P , Khedkar M V , Jadhav S A , Somvanshi Sandeep B. , Humbe A V , Jadhav K M
Published: October 2020

Abstract In the present study, Barium Titanate (BaTiO3) nanoparticles were synthesized using one of the best route chemical method that is sol-gel auto combustion method. The structural and dielectric properties were investigated by powder X-ray diffraction (XRD), LCR meter and the results are reported herein. The phase purity and structural determination was carried by XRD technique at room temperature. The analysis of XRD patterns revealed of formation of single phase tetragonal structure. The lattice parameters ‘a’ and ‘c’ were obtained using XRD data and obtained lattice parameters matches with reported value. Average crystallite size was determined using Debye–Scherrer’s formula and is found to be 6.4 Å indicating nanocrystalline nature. Dielectric properties like dielectric constant and dielectric loss tangent was investigated using LCR-Q meter method at varying frequencies. Both dielectric constant and dielectric loss tangent decreases with increasing frequencies. The PE characteristics and other studies are in progress.
Structural, Morphological and Magnetic Properties of Cu2+ Doped ZnO Nanoparticles
Authors: Undre Pallavi G. , Kharat Prashant B. , Kounsalye Jitendra S. , Kathare R. V. , Jadhav K. M.
Published: October 2020

Investigations on the structural, morphological and magnetic properties of Zn1-xCuxO (x=0.00 and 0.05) nanoparticles synthesized via simple and low cost sol-gel auto combustion technique. The synthesized samples were characterized by X-ray diffraction technique (XRD), and vibrating sample magnetometer (VSM). XRD pattern reveals the formation of single phase with hexagonal wurtzite structure of both the synthesized samples. It also confirms the sucssefully incorporation of dopant (Cu2+) into the ZnO lattice. The lattice parameter of Cu2+ doped ZnO is slightly greater than that of pure ZnO nanoparticles. The crystallite size of synthesized samples are as 21 and 19 nm in range. Magnetic study carried out by VSM at room temperature and shows the diamagnetic nature of pure ZnO nanoparticles. After the doping of Cu2+ ions in ZnO changes to ferromagnetic nature. The apperance of ferromagnetism due to the presence of free carriers induced by Cu2+ doped into ZnO nanoparticles.
Synthesis of N-Mannich bases from 3, 4-dihydropyrimidin-2(1H)-ones by using nanostructured Cobalt Chloride Doped Polyaniline Composite as Catalyst (PANI-Co)
Authors: Nagrik Deepak M. , Shelke Umesh S.
Published: October 2020

The Mannich reaction is the type proton assisted of carbon-carbon bond formation reaction that involves the addition of resonance-stabilized carbon nucleophiles to iminium salts and imines. The product of the Mannich reaction is (3-amino carbonyl compounds of biological interest synthesized from the aldehyde, amine, and carbonyl compounds. This reaction is very limited to the only highly reactive aldehydes such as formaldehyde and acetaldehyde, a secondary amine. The direct Mannich-type reaction expanded with the development of the scope of Mannich reaction, and very much efficient method for highly stereo selective type Mannich reactions were extensively well studied and reported in the literature. This study aimed at investigating the synthesis of N-Mannich Bases from the 3, 4-Dihydropyrimidin-2(1H)-ones by using nanostructure Cobalt Chloride Doped Polyaniline composite as Catalyst (PANI-Co). The Synthesis of N-Mannich Bases from 3, 4-Dihydropyrimidin-2(1H)-ones by using nanostructure Cobalt Chloride Doped Polyaniline composite as Catalyst (PANI-Co) was carried out. The effective method for the synthesis of the Mannich bases of synthetically important compounds has been coined. We synthesized the different Mannich Bases from 3, 4-Dihydropyrimidin-2(1H)-ones which give up to 94 % yield.
Soil Characterization Using Physical and Chemical Properties
Authors: Disale A S , Chavan D P , Alameen A S , Undre P B
Published: October 2020

This paper presents the influences of soil chemical composition on pH. Surface soil samples from bare ground without vegetation were collected from different locations of Pune district of Maharashtra State from the top 8 inch at each sampling sites using a sterile shovel. A total of 146 samples were collected and directly put into sterile sampling bags. Physical and chemical properties of soil a total of eleven soil properties were assessed, including pH, Organic Carbon (OC), Nitrogen (N), Calcium Carbonate (CaCO3), Sodium (Na), Potassium (K), Phosphorus (P), Iron (Fe), Manganese (Mn), Copper (Cu) and Zinc (Zn). Pearson’s correlation coefficients studies were employed to highlight the influence of the chemical composition on pH values. It was observed that OC, P, and Na have a significant influence on measured pH values. Whereas there was very low correlation with the N, K, CaCO3, Fe, Mn, Cu and Zn.
Microwave Dielectric characterization of Ayurvedic Medicine using Time Domain Reflectometry Technique
Authors: Chavan D. P. , Londhe C. T. , Disale A S , Undre P B
Published: October 2020

The dielectric dispersion e’ and dielectric loss e” of ayurvedic medicine such as arjunarishta, khadirarishta and lohasava as were measured by employing the Time Domain Reflectometry technique over a frequency range 10 MHz to 20 GHz at 15, 25, 35 and 45°C. The accuracy in the measurement of the e’ and e” values obtained from this technique is within ±5%. To evaluate various dielectric parameters, the frequency dependents complex permittivity (e* (co) = e’ - je”) data viz., dielectric constant, relaxation time and permittivity at high frequency (eoo) were fitted by the non-linear least-squares fit method to Debye expression. Temperature dependent dielectric constant (e0), and relaxation time (x) have been determined. Further the variation in dielectric parameters and molecular reorientation due to change in the molecular structure has been explored by comparing the values of dielectric parameters of arjunarishta, khadirarishta and lohasava.
Study of Volumetric and Optical Properties of Cerium Oxide Nano-Fluid
Authors: Yaseen S A , Alameen A S , Saif F A , Undre S B , Undre P B
Published: October 2020

The study of volumetric and optical properties for cerium oxide nanoflakes dispersed in folic acid and water have been reported for entire concentration range (25 to 150 µM) at room temperature. Cerium oxide nanoflakes have unique properties and emerged in biomedical science field applications. The synthesized nanoflakes was investigated by various spectroscopic, structural and morphological techniques. Volumetric properties including density, apparent molar volume and excess molar volume, optical properties such as refractive index, molar refraction and electronic polarizability have been obtained for the nano-fluid system undertaken and optical absorbance spectra were recorded using UV-vis spectrophotometer for fresh sample and after one week suspension at room temperature. The study of volumetric behaviour of solutions may provide useful information about intermolecular interactions that take place in nano-fluids such as solute–solute, solute–solvent, dipole-dipole interactions and other dispersive forces and help to improve industrial productions and medical applications.
A nano polymer aggregate on a substrate: A Theoretical study
Authors: Kumar Mishra Pramod
Published: October 2020

We use lattice model to investigate the thermodynamics of an ideal semi-flexible polymer chain at the nano scale. The polymer chain is assumed to polymerize on the nano size substrate and the conformations of the chain were realized on the substrate using a square lattice. Our analytical estimates show clear distinctions in the thermodynamics of the polymer chain from its corresponding bulk . The persistent length versus stiffness curve varies linearly at the possible small length scale but in the bulk this variation is gradual. The polymer chain is confined from each direction and therefore, the nature of the force of confinement on a flexible and a semi-flexible chains has also been discussed for the proposed nano scale confinement.
Nanocatalyst: A Brief Review on Synthesis to Applications
Authors: Somwanshi Saurabh B. , Somvanshi Sandeep B. , Kharat Prashant B.
Published: October 2020

As the world is at present confronting tremendous issues concerning the atmosphere, energy, and the environment, catalysis innovations have all the earmarks of being getting critical to energy, synthesis process, and environmental areas. In the recent years, transformation of the research on catalytic activities and advanced catalyst was seen with the advancement of nanotechnology. Undoubtedly, the utilization of nanomaterials in catalysis and, all the more especially, inorganic nanoparticles has pulled in many research attempts over the globe to create imaginative and greener conventions. These nanoparticles can be used as the catalyst or as mediator and can encourage the reactant procedure in new medium such as, water. Besides, attributable to their little size and expanded surface area, nano-catalysts have obviously risen as offering an interesting candidate at the interface among homogeneous and heterogeneous catalysis, taking into consideration an expanded response rate. Furthermore, nanoparticles give extra reactant functionalities because of their interesting inherent properties (e.g., nanomagnetism, photocatalytic activity). Along these lines, in this pursuit for eco-friendly and more affordable catalyst, nano-catalysis is turning into a significant field in science, which is applied broadly in the academics and industrial areas. This brief review principally centered around portraying the major comprehension of nano-catalysis, how remarkable catalytic property and other explicit properties of nanomaterials rely upon its size and structure at the nano level.
Synthesis and characterization of highly hydrophobic, oil-absorbing aerogels for oil spill applications; A Review
Authors: Gajanan Patil Pradnya , Sharma R. P. , Chakrabarty Aurab
Published: October 2020

The review report reflects on the potential of highly hydrophobic silica aerogel as a viable material for oil absorption application in the clean-up of oil spills on oceans. The review presents the conventional clean-up technologies, silica aerogel synthesis and coatings by sol-gel method and simulation techniques to predict the maximization of efficiency as well as mechanical characteristics for practical applications.
Synthesis, Structural and Spectroscopic investigation of Gd2(WO4)3 phosphor
Authors: Shruthi D L , Shanker Ojas , Gowda Likith , Kudige Pranav , Jagannatha Reddy A , Anil Kumar G N
Published: October 2020

In the present work we synthesis Gd2(WO4)3 phosphor by hydrothermal method. X-ray diffraction results show that the samples are crystallized in monoclinic crystal structure without any impurity phases. Rietveld refinement data confirms the phosphors belong to space group C2/c. FTIR spectra showed the stretching and bending vibration modes. UV-Visible absorption spectroscopy illustrate the optical band gap (Eg) value of prepared sample. SEM micrographs indicate the agglomerated spherical particles. Gd2(WO4)3 phosphor exhibits high optical and structural stability.
Biodiversity study of several peatland types in Papua
Authors: Sundari S , Ibo L K , Rahajoe J S , Alhamd L , Gunawan H , Priyono N C
Published: October 2020

Research on biodiversity study of several peatland types in Papua had been carried out in Merauke and Mappi. The plot method was used for ecological research and interviews method for ethnobotany research. The results showed that the most important species which have the highest Importance Value Index (IVI) were Beilschmiedia sp., Carallia brachiate (Lour.) Merr., and Kibara coriacea (Blume) Hook. f. & A. Thomps. in Kaliki Village, whereas it was Melaleuca leucadendra (L.) L only in Marga Mulia Village, Merauke. The most important species which have the highest IVI were Semecarpus forstenii Blume, Archidendron clypearia (Jack) I.C. Nielsen, and Campnosperma auriculatum (Blume) Hook.f. in Khanami Village, while they were Calophyllum euryphyllum Lauterb, Diospyros toposiodes King & Gamble, and Syzygium effusum (A.Gray) Müll. Stuttg in Yame Village, Mappi. The plants are used for building materials and ships, medicinal materials, food ingredients, animal feed, energy-producing materials/firewood, and material in traditional rituals.
Modification of rice biomass wastes for eco-friendly particleboard
Authors: Sejati P S , Kusumah SS , Dwianto W , Surjasa D
Published: October 2020

Rice husk and rice straw are some of abundantly available agricultural wastes that could substitute the utilization of wood as particleboard raw-materials. Nevertheless, recent studies show that rice husk and rice straw instigated low mechanical and physical properties of particleboard. Modification of rice husk and rice straw particle was investigated in order to improve particleboard properties by immersing rice husk and straw in boiling water (100°C) for 0.5, 1, 2 h and in Na2CO3(80°C) for 1 h, and combination of rice husk as face and back layers and rice straw as core layer. The boards were manufactured under pressing conditions of 200°C for 10 min used citric acid and sucrose as adhesive. Pre-treatment of 1 h boiling water of particle resulted the highest quality of all properties and satisfy the JIS 5908 (2003) requirement in Modulus of Rupture (MOR) and Internal Bonding (IB). Combining rice husk as face and back layer and rice straw as core layer resulting in IB improvement. Compared to the other adhesives, citric acid and sucrose adhesives showed better mechanical and physical properties for rice husk and rice straw particleboard manufacturing.
Characterization and symbiotic evalution of rhizobium bacteria from various plants on soybean (Glycine Max L) plants in green house
Authors: Purwaningsih S , Agustiyani D , Antonius S
Published: October 2020

Rhizobium bacteria are bacteria including Plant Growth Promoting Rhizobacteria (PGPR) that are able to fix nitrogen, solubilise phosphate, produce enzymes of protease, IAA hormone and siderophore so that it plays, an important role in increasing agricultural productivity. Several rhizobia have been successfully isolated from 8 legume plants from various regions, with the aim of obtaining Rhizobium isolates which are potential, effective and efficient as biological fertilizer agents. A total of 8 isolates were successfully isolated using selective media for Rhizobium bacteria, namely YEMA, following their activities were tested qualitatively N fixing, solubilise phosphate, protease, IAA hormone and siderophore production. All isolates thrive on YEMA+CR media and showed fast growth in YEMA + BTB.. A total of 11 inoculation treatments were tested on soybean plants consisting of 1. EKP (3), 2. EKP (4), 3. i (1), 4 (combined 1-3), 5. 1 (2), 6. B (1), 7. H (2), 8 ( combined 5-7), 9. A (2), 10.2 (1), 11 (combined 9-10). As a control plant without inoculation and without N fertilizer (K1) and plants without inoculation and with N fertilizer equivalent to 100 kg/ha (K2). The planting media used for greenhouse experiments were sterile sand media. The experimental design used were a completely randomized design with 3 replications. Plants growth were observed with parameters included plant height and number of leaves (at 1,2,3,4,5,6 and 7 weeks). Soybean plants werw harvested at 50 days after planting, following measurement of dry weight of canopy, roots, root nodules, total plants and chlorophyll content. The results showed that 8 individual isolates and 3 combined isolates inoculated to soybean plants varied, all of which were able to increase growth. Isolates number H(2) and 1(2) (isolates of nodules root of Peanut plants) gave the highest yields on the growth of soybean plants.
Isolation and Identification Of Ascomycetous Yeast Producing Phytase
Authors: Kanti A , Sumerta I N , Idris I , Napitupulu T P , Ikhwani AZN
Published: October 2020

The objective of the study was to isolate, identify and characterize phytase producing yeast. The yeast was isolated from various resources, and the identification of yeast was conducted by the sequencing of the ITS region. Of 41 isolates, 24 isolated produced phytase. The highest phytse producing yeast was identified as Candida natalensis YEG 132, Saturnispora quitensis YEg 135, and Candida albicans YEg 226. These isolates were able to use various carbon and nitrogen sources. The maximum phytase production depends on isolates, media composition, pH and incubation temperature. Temperature affected phytase production. All isolates produce the highest phytase was at 30°C. Increased temperature to 35° C and 40°C inhibits phytase production by all strains. S. quitensis was the highest isolate inhibited by an increase of incubation temperature. The pH of cultures affects phytase production and varies depending on isolate. S. quitensis and Candida natalesis produced the highest phytase activities at pH 5.0, while C. albicans was at pH 6.0. All isolates were able to assimilate glucose, dextrose, sucrose, xylose and lactose. In general, glucose was the best carbon source for phytase activity. But each isolate has its preferential on carbon sources. S. quitensis produced the highest phytase on glucose, but not on dextrose. Each isolate has preferential on nitrogen sources. Yeast extract was the best N-sources for C. albicans, while ammonium sulfate was best for C. natalensis, S. quitensis. Ammonium nitrate was not favorable for phytase production by C. natalensis. Candida natalensis YEG 132, Saturnispora quitensis YEg 135, and Candida albicans YEg 226 was a good candidate for phytase production.
Biodegradation of Acetonitrile and Benzonitrile by a Newly Isolated Rhodococcus Pyridionvorans Strain I-Benzo from Leather Tanning Waste
Authors: Sulistinah N , Sunarko B
Published: October 2020

Nitriles are toxic organo-cyanide compounds, but extensively used in various industries as solvents, plastics, synthetic rubber, pharmaceuticals, herbicides, and starting materials for other industrially important chemicals. The wider use of these toxic compounds could lead to an environmental pollution, which have a negative impact on health. Some microbes are reported to be able to utilize both aliphatic and aromatic nitrile s as growth substrates and convert them into non-toxic compounds, some of which also have economic value as well. An indigenous bacterial isolate I-benzo, capable of growing on and utilizing of a high concentration of acetonitrile (CH3CN) and benzonitrile (C6H5CN), could be isolated from leather tanning waste by the enrichment-culture technique. Based on 16S rDNA sequence, the strain was identified as Rhodococcus pyridinivorans. These bacterium was shown to able to grow on acetonitrile (0.2-2.0 M) and on benzonitrile (5-25 mM), as a sole source of energy, carbon and nitrogen, respectively. The best growth of R. pyridinivorans strain I-benzo was on 500 mM acetonitrile and on 15 mM benzonitrile. During the degradation of both nitriles using whole cells of the bacterium, amide and carboxilic acid were detected in the reaction media, indicating that nitrile hydratase and amidase involved in the metabolism of the substrate. The involvement of both enzymes on the conversion of acetonitrile and benzonitrile was also proved by the ability of R. Pyridinivorans I-benzo to grow on their intermediate degradation products, acetamide (CH3CONH2) and benzamide (C6H5ONH2), respectively. Based on these results, R. pyridinivorans strain I-benzo could be expected as a potential candidate for biological treatment for nitriles-containing wastes, although further research is still needed before being applied on a field scale.
Optimization of lacease production from a newly isolated Trametes sp. EDN134
Authors: Ningsih F , Yanto D H Y , Mangunwardoyo W , Anita S H , Watanabe T
Published: October 2020

Laccase is one important enzyme in decolorization of textile dyes. This research aims to study the optimization of laccase production from Trametes sp. EDN134 under several variation of substrates (bagasse, bamboo, Jabon wood, oil palm empty fruit bunch (OPEFB), and sorghum fibers), time incubation (1-15 d), growth temperature (25, 27, 30, 32, 35 and 37°C), and concentrations of inducer CuSO4 (1, 2, 3, 4 and 5 mM). The results showed that optimum laccase specific activity (14,838 U/g) detected in the OPEFB medium at 10 days incubation, temperature 30°C and CuSO4 2 mM. The study suggests that these parameters could be used for the optimization of laccase production from a newly isolated Trametes sp. EDN134.
Isolation of Indole Acetic Acid (IAA) producing Bacillus siamensis from peat and optimization of the culture conditions for maximum IAA production
Authors: Suliasih  , Widawati S
Published: October 2020

Indole acetic acid (IAA) is a phytohormone which one of the important compounds for plant growth and development, affecting as inducing cell elongation, cell enlargement and cell division. IAA synthesized both in the plants and microorganisms. For microorganisms, production of phytohormone IAA is one of the essential criteria for plant growth promotion. The aim of the present study was to isolate and screen IAA producing bacteria from peat land area in West Kalimantan and optimized some culture conditions for maximum IAA production. The production of IAA was determined in TSB and YEMB liquid medium and the optimization of IAA production in culture media was carried out at different of incubation time, L-Tryptophan concentrations, carbon and nitrogen sources, pH and temperature. The result revealed that maximum IAA production of Bacillus siamensis was achieved at 96 hours of incubation. The YEMB medium supplemented with 250 ppm of tryptophan was obtained as the best medium for IAA production (9.89 μg/ml). This bacterium produced optimum levels of IAA in the presence of sucrose (10.23 μg/ml) and tryptone (16.61 μg/ml) as carbon and nitrogen sources respectively. In the physical parameters, the maximum production of IAA was recorded at T 35°C (8.42 μg/ml) and a pH of 8.0 (13.29 μg/ml).
The Analysis of tropical cyclones that occurred in the southern sea of Java during the period 2004-2019 and their effects on sea-atmospheric conditions
Authors: Sofiati I , Putranto MF
Published: October 2020

Tropical cyclones are an important part of the atmospheric circulation system, which transfers heat from the equatorial region to higher latitudes. The birth of a tropical cyclone will have an impact on increasing the intensity of heavy rain, wave height, strong winds, and the potential for lightning. The purpose of this study is to analyse tropical cyclones and their impact on ocean and atmospheric conditions that occur in the southern of Java. The data used in this study is hourly rainfall data, Madden Julian Oscillation (MJO), wind (direction and speed), significant wave height, sea surface temperature, and sea level pressure hourly from the European Centre for Medium-Range Weather Forecasts (ECMWF). The method used in this study is averaging hourly data into daily data for each sea-atmospheric parameter during the 16-years observation period (2004-2019), and representing it in the form of descriptive daily on before, being and after the occurrence of tropical cyclones. From the results of the analysis it can be concluded that there were 17 tropical cyclones which mostly occurred in April, resulting in a significant increase in intensity of sea-atmospheric parameters (rainfall, significant wave height, and wind direction & speed), but decreased for sea level pressure. As from the Riley tropical cyclone event that occurred on (24-26) January 2019, rainfall increased in intensity to 951 mm/day, significant wave heights reaching more than 4 m with wind speeds of more than 17 m/sec, sea level pressure is less than 947 hPa, and the average MJO condition is in phase 2, 3, 4, or 5, with a strong period.
Configuration of Bayesian Model Averaging Training Window to Improve Seasonal Rainfall Ensemble Prediction
Authors: Muharsyah R , Hadi T W , Indratno S W
Published: October 2020

Bayesian Model Averaging (BMA) is a statistical post-processing method for producing probabilistic forecasts from ensemble prediction in the form of predictive Probability Density Function (PDF). It is known that BMA is able to improve the reliability of the probabilistic forecast of short-and medium-range rainfall forecasts. This study aims to develop the application of BMA to calibrate long-range forecast in order to improve the quality of the seasonal forecast in Indonesia. The seasonal forecast that has been used is monthly rainfall from the output of the ensemble prediction European Center for Medium-Range Weather Forecasts (ECMWF) system 4 model (ECS4). This model was calibrated against observational data at 26 stations of Agency for Meteorology, Climatology and Geophysics of Republic of Indonesia (BMKG) over Java Island in 1981-2018. BMA predictive PDF was generated with a Gamma distribution which was obtained based on Training Window Sequential (TWS) and Conditional (TWC) training windows. Output of BMA-TWC was slightly better than BMA-TWS. Nevertheless, both of them were superior to raw model ECS4. BMA-TWC or BMA-TWS output was varying depend on spatial and temporal, but in general, the best result was in the dry season and during the El Nino phase. BMA was able to improve the distribution characteristics of ensemble prediction. BMA also increased the skill, resolution, and reliability of probability forecast of Below Normal (BN) and Above Normal (AN). Furthermore, the reliability of BN and AN of BMA output were also have the categories of “still very useful” and “perfect” compared to raw model ECS4 that were in the “dangerous” and “not useful” categories. The reliability “still very useful” and “perfect” show that the probabilistic forecast of BN and AN event can be used for making decisions related to seasonal forecast especially over Java island.
The Utilization of Oil Palm Leaves (Elaeis guineensis Jacq.) Waste as an Antibacterial Solid Bar Soap
Authors: Febriani A , Syafriana V , Afriyando H , Djuhariah Y S
Published: October 2020

Oil palm leaves (Elaeis guineensis Jacq), which have been underutilized by the community and become waste that usually stacked around the trees, have a potential to be used as active ingredients for making antibacterial solid bar soap. The chemical content of oil palm leaves are tannins, alkaloids and flavonoids that known had antibacterial activity. This research aims to produce oil palm leaves extracts into an active ingredient of solid bar soap formulation with antibacterial activity against Escherichia coli and Staphylococcus aureus and also to evaluate the quality of the solid bar soap. The soap was formulated into 3 formulas with varying concentrations of oil palm leaves ethanolic extract that was F1 (1% ), F2 (2%), and F3 (4%). Oil palm leaves extract was prepared with maceration using ethanol 70%. Antibacterial activity assay of the solid bar soap was carried out using a disc diffusion method with tetracycline as the positive control (K+) and distilled water as the negative control (K-). The soap quality was evaluated for its organoleptic, foam level and foam stability, pH, hardness, water content and free fatty acid. The results showed that all three solid soap formulas meet the soap quality requirements of SNI No. 3532-2016. The solid bar soap did not have inhibition properties against Escherichia coli. However, had inhibition effect against Staphylococcus aureus with an average Inhibition Zone Diameter (IZD) on soap base, F1, F2, and F3 was 8.02 mm, 8.53 mm, 10.53 mm, 12.91 mm respectively.
Characterization and reduction behavior of carbon-infiltrated goethite ore by impregnation of tar recovered from coke oven gas
Authors: Hariyadi A , Cahyono R B , Purwono S
Published: October 2020

The Iron/Steel industry is currently facing serious problem due to excessively dependent on metallurgical coke, which is produced a large amount of CO2 emission and it was limited source in Indonesia. Coke-free iron-making is one of the efficient method to reduce the amount of cokes. Carbon-infiltrated iron ores were prepared by impregnation process from coaltar solution and goethite ore at 500 °C and 600 °C to promote direct reduction in iron making. These variables were systematically characterized by XRD and SEM/EDX. Pore distribution and BET surface area were determined by N2 adsorption-desorption measurement. The XRD signals attributed to Fe2O3 in the goethite ore were completely disappeared and replaced by signals attributed to Fe3O4 after impregnation process. Cross-sectional analyses of composite particles prepared using both temperatures showed that tar-derived carbonaceous materials have completely either impregnated or vapor infiltrated into the mesoporous in pyrolyzed goethite ore. Carbon-infiltrated goethite ore showed a higher reduction degree than conventional coke. It is confirmed that high reactivity of carbon-infiltrated iron ores is due to close contact between the goethite ore and carbon in its nanoporous interior facilitated the fast reduction.
Particle Size Distribution and Yield Analysis of Different Charged Cellulose Nanofibrils Obtained by TEMPO-mediated Oxidation
Authors: Masruchin Nanang , Amanda Putri , Kusumaningrum Wida Banar , Suryanegara Lisman , Nuryawan Arif
Published: October 2020

Cellulose Nanofibrils (CNF) was successfully obtained by TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl radical)-mediated oxidation with the addition of different oxidant namely NaClO (Sodium Hypochlorite) i.e. 3, 4, 7, 10 and 15 mL followed by ultra-sonication treatment. Size distribution of nanocellulose was observed using particle size analyzer, while surface charged was measured using zeta potentiometer. At different level of oxidant, CNF obtained different charged with different size distribution. As the amount of oxidant increased, the size distribution of CNF increased which correlated to the higher CNF yield, however it decreased at maximum oxidant addition. Although, in general the yield for nanocellulose was very low. With zeta potential value about -48 mV, it showed very stable suspension in water for more than 8 months observation. An optimum oxidant level promoted thinner and longer CNF which further beneficial for better entanglement in the hydrogel formation application.
Socio-Economic Analysis of Traditional Diamond Mining Community in Banjarbaru City, South Kalimantan
Authors: Akmiyati N , Damoiko RM , Ulfah R , Najmi H , Abdurrahim AY , Rahiem MDH , Ramli M
Published: October 2020

Since the 8th century, the South Kalimantan region was known as a diamond producer, especially in the Cempaka Sub-District, Banjarbaru City. Local communities have carried out the work as a traditional diamond miner for generations in groups with a system of division of labor and results. This study aims to determine the effect of diamond mining on the socio-economic conditions of the miners, especially related to income and expenditure. Primary data collection was carried out in May-Augustst 2018 in the Cempaka diamond mining location through field observations, in-depth interviews, FGDs, and questionnaires. Based on David Ricardo’s theory, the informants and respondents were grouped into three categories: diamond miners, landowners, and diamond polisher. The analysis showed that diamond mining contributes to all, but with different income levels. The average monthly income of diamond miners (Rp 1,147,222.22) is the smallest compared to diamond polisher (Rp 2,125,000.00) and landowners (Rp 3,625,000.00). For average expenditures per month, each of which is sequentially Rp 1,186,239.35; Rp 1,020,658.33; and Rp 1,273,950.00. This indicates a deficit between income and expenditure of diamond miners. The deficit was covered by various programs from the government, such as food assistance for poor households (‘Raskin’). The study also showed differences in the socio-economic characteristics of diamond miners, diamond polishers, and landowners.