Journal Of Natural Sciences And Mathematics Research
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Effect of Growth Pressure on Structural Properties of SiC Film Grown on Insulator by Utilizing Graphene as a Buffer Layer
Full text linkHeteroepitaxial growth of silicon carbide (SiC) on graphene/SiO2/Si substrates was carried out using a home-made hot-mesh chemical vapor deposition (HM-CVD) apparatus. Monomethylsilane (MMS) was used as single source gas while hydrogen (H2) as carrier gas. The substrate temperature, tungsten mesh temperature, H2 flow rate and distance between mesh and substrate were fixed at 750 °C, 1700 °C, 100 sccm and 30 mm, respectively. The growth pressures were set to 1.2, 1.8 and 2.4 Torr. The growth of 3C-SiC (111) on graphene/SiO2/Si were confirmed by the observation of θ-2θ diffraction peak at 35.68°. The diffraction peak of thin film on graphene/SiO2/Si substrate at pressure growth is 1.8 Torr is relatively more intense and sharper than thin film grown at pressure growth 1.2 and 2.4 Torr, thus indicates that the quality of grown film at 1.8 Torr is better. The sharp and strong peak at 33° was observed on the all film grown, that peak was attributed Si(200) nanocrystal. The reason why Si (200) nanocrystal layer is formed is not understood. In principle, it can’t be denied that the low quality of the grown thin film is influenced by the capability of our home-made apparatus. However, we believe that the quality can be further increased by the improvement of apparatus design. As a conclusion, the growth pressures around 1.8 Torr seems to be the best pressures for the growth of heteroepitaxial 3C-SiC thin film
Analisis Aspek Molekuler Biomarka Alkana Bercabang Core Badak 1/208 Muara Badak, Kutai Kartanegara, Kalimantan Timur
Full text linkStudy compound biomarka branched alkanes on core 1/208 Rhinos have done to contribute to the activities of oil exploration wells 1/208 Muara Badak Badak, East Kalimantan's Kutai Kartanegara-through core biomarka profile branched alkanes. Core samples extracted by alternately with solvent mixture of toluene-methanol (3: 1) and chloroform-methanol (3: 1). Then fractionated by Column Chromatography and Thin Layer Chromatography to obtain aliphatic hydrocarbon fraction. Fractions obtained were identified using Gas Chromatography-Mass Spectrometry.The content biomarka aliphatichydrocarbon fraction were identified, among others, iso and anteiso alkanes, mono and trimethyl alkanes. Compounds iso and anteiso alkanes, and alkyl alkane other, providing information that the source of organic material core samples I and II is derived from microorganisms prokaryotic or biogenic precursor derived from cyanobacteria (marine microorganisms) and homologous monomethyl alkanes found in core samples II closer homologous series monomethyl alkanes found in sediments and oil and Precambrian Proterozoic era, so it can be said that the core sample II core samples older than I
Modified Variational Iteration Method with Chebyshev Polynomials for Solving 12th order Boundary Value problems
Full text linkWe consider in this paper an illustration of the modified variational iteration method (MVIM) as an effective and accurate solver of 12th order boundary value problem (BVP). For this reason, the Chebyshev polynomials of the principal kind was utilized as a premise capabilities in the guess of the logical capability of the given issue. The strategy is applied in an immediate manner without utilizing linearization or irritation. The subsequent mathematical confirmations recommend that the strategy is without a doubt successful and exact as applied to a few direct and nonlinear issues as mathematical trial and error. Maple 18 was used for all computational simulations carried out in this research.©2022 JNSMR UIN Walisongo. All rights reserved
Analysis of the optical properties of ZnO thin films deposited on a glass substrate by the So-gel method
Full text linkZinc oxide (ZnO) has attracted the attention of researchers as a photocatalyst material, because ZnO has a wide direct band gap (3.37 eV) and is a semiconductor material with a large excitation binding energy (60 meV). ZnO is a photocatalyst that has many advantages, namely cheap, non-toxic, and theoretically very active under UV irradiation. The most interesting thing about ZnO semiconductor compared to other semiconductors is that ZnO can absorb most of the solar spectrum. However, there is a weakness of the ZnO semiconductor, namely the very fast recombination of charge carriers and the ZnO semiconductor has a low efficiency in the visible region which causes the ZnO semiconductor to have a wide band gap. that is the weakness of ZnO. it is necessary to choose the right method to overcome this deficiency of ZnO. one way that can be done is to increase the photocatalytic ability of zinc oxide, it is necessary to develop it in the manufacture of thin films. The method used in the manufacture of Thin Film is using the sol-gel spray coating method. the first stage is through the manufacture of ZnO precursors by dissolving zinc acetate dehydrate with isopropanol solvent through stirring. then the second stage by adding Monoethanolamine. This stirring lasted for 30 minutes at a temperature of 70°C, the precursor concentration was prepared with three different concentrations which included concentrations of 0.1, 0.3, and 0.5 M. ZnO precursor deposited on the substrate glass is blown at 400 °C. Optical properties are carried out by recording the transmittance and absorbance which are affected by increasing concentrations. The optical transmission spectra show that the transmission increases with decreasing concentration and the maximum transmission in the visible region is about 90% for ZnO thin films prepared with 0.1 M. The optical band gap value produced by the thin film of 0.1 M precursor concentration resulted in an energy band gap of 3.11 eV; thin films of 0.3 M precursor concentration produced an energy band gap of 3.07 eV; and thin film of 0.5M precursor concentration produced an energy band gap of 3.06 eV.©2022 JNSMR UIN Walisongo. All rights reserved
Bioplastic from Cassava peel and eggshell waste
Full text linkThe accumulation of plastic waste and excessive use of plastic is a common environmental issue in Indonesia. Plastics are synthetic polymers that are stable, water-resistant, light, flexible, and firm but very difficult to break down by microorganisms. Decomposition of plastic waste by burning can cause other environmental issues and, during the combustion process can produce dioxin compounds that are harmful to health. An available and affordable alternative to reduce the use of plastic is by using bioplastics. Bioplastics are plastics made from natural materials that microorganisms can break down, so they are more environmentally friendly than commercial plastics. Generally, the main ingredients for making bioplastics are starch or chitosan. The source of starch used in this project comes from cassava peel waste. In this project, researchers also utilize waste from chicken eggshells. The function of adding eggshell waste is to give biodegradable plastic complex characteristics. The ratio between cassava peel and eggshell used was 1:0, 1:1, 1:3, and 1:5. With a 1:1 ratio is the most optimal. The addition of eggshells with the correct ratio (1:1) increased the ability of biodegradation of bioplastics. The results of the Tensile Strength Test of Bioplastic Samples with a ratio of 1:0, 1:1, 1:3, and 1:5 are 9.2 x10-3kgf/cm2, 4.4 x10-3 kgf/cm2, 2 x10-3 kgf/cm2, and 2 x10-3 kgf/cm2.©2022 JNSMR UIN Walisongo. All rights reserved
Identification of alteration zone and gold mineralization based on magnetic anomaly and 3D model of geomagnetic satellite data inversion of Mount Pongkor Area, West Java
Full text linkMount Pongkor is one of the areas in Indonesia with the largest gold mineralization potential in Java. One of the geophysical methods to identify the distribution of gold mineralization zones is the geomagnetic method that utilizes magnetic properties in the subsurface due to the influence of rock magnetization. Geomagnetic research has been conducted at Mount Pongkor, Bogor Regency, West Java with an area of 22 x 17 km as much as 793 magnetic satellite data from the National Oceanic and Atmospheric Administration (NOAA) website that has been corrected daily. This study aims to determine the distribution of alteration zones and mineralization of the study area. The results showed that the RTP map shows the distribution of magnetic anomalies ranging from -4.786 – 4.663 nT, with high anomalies in the north-south direction associated with mineralization zones with anomaly values ranging from 1.881 – 4.663 nT and low anomalies in the north-south direction associated with rock alteration zones with anomaly values ranging from -4,786 - (-2.174) nT. In the 3D inversion model, the alteration zone has an average depth of 350 - 2600 m from topography with susceptibility contrast values ranging from -0.35 - (- 0.25) SI and the mineralization zone has an average depth of 350 - 2800 m from topography with susceptibility contrast values of 0.25 - 0.35 SI.©2022 JNSMR UIN Walisongo. All rights reserved
Red Ginger oleoresin nanoemulsion characteristics by ultrasonication
Full text linkRed ginger is a biopharmaceutical plant that is used as herbal medicine. The use of red ginger in the food industry is mainly in an emulsion form, but that is unstable and hydrophobic. The ultrasonication technique could change the emulsion into a nanoemulsion to minimize these disadvantages. This research aimed to determine the effect of ultrasonication on red ginger oleoresin nanoemulsion characteristics. The study used a completely randomized design of 4 treatments based on sonication time (0, 30, 60, and 90 minutes). The study was analyzed by ANOVA Tukey's test at P ≤ 0.05, it showed that ultrasonication affected the characteristics of red ginger oleoresin nanoemulsion. The best result shows that in 90 minutes mixed time with transparent yellow colour. It is soluble in acetone, methanol, ethanol, and aquadest solvents. The best particle size is 572.43±8.72 nm, and antioxidant activity is (IC50) 16.34 ±1.33 ppm.©2022 JNSMR UIN Walisongo. All rights reserved
Fixed point results in α, β partial b-metric spaces using C-contraction type mapping and its generalization
Full text linkBanach contraction mapping has main role in nonlinear analysis courses and has been modified to get new kind of generalizations in some abstract spaces to produce many fixed point theory. Fixed point theory has been proved in partial metric spaces and b-metric spaces as generalizations of metric spaces to obtain new theorems. In addition, using modified of contraction mapping we get some fixed point that have been used to solve differential equations or integral equations, and have many applications. Therefore, this area is actively studied by many researchers. The goal of this article is present and prove some fixed point theorems for extension of contraction mapping in α, β partial b-metric spaces. In this research, we learn about notions of b-metric spaces and partial metric that are combined to generated partial b-metric spaces from many literatures. Afterwards, generalizations are made to get α, β partial b-metric spaces. Using the properties of convergence, Cauchy sequences, and notions of completeness in α, β partial b-metric spaces, we prove some fixed point theorem. Fixed point theory that we generated used C-contraction mapping and its generalizations with some conditions. Existence and uniqueness of fixed point raised for some restrictions of α, β conditions. Some corollaries of main results are also proved. Our main theorems extend and increase some existence in the previous results.©2022 JNSMR UIN Walisongo. All rights reserved
Application of the Smith Waterman and Jukes Cantor Algorithm in the Arrangement of the SARS CoV-2 Virus
Full text linkIn early 2020, the world was shocked by an outbreak of a new pneumonia that started in Wuhan, Hubei Province, which then spread rapidly to more than 190 countries and territories. This outbreak was named coronavirus disease 2019 (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). The spread of this disease has had a wide social and economic impact. There is still a lot of controversy surrounding this disease, including in the aspects of diagnosis, treatment, and prevention. Therefore, a study was carried out on studies related to COVID-19 that have been widely published since the beginning of 2020 until the end of March 2020.So to overcome this problem, the Smith Waterman Jukes Cantor Algorithm was made to align Covid19 by taking the a pair of DNA and RNA sequencesto align protein sequences. From this alignment, the percentage of identical and mutations will be known. The identical percentage in the genetic code will prove that although the symptoms caused by the disease are almost the same, the protein sequences are not necessarily the same. Based on the simulation results of the distance between sequences that produce a phylogenetic tree using the jukes cantor method, it was obtained that 4 groups of 26 sequences were divided into groups, namely, group 1 consists of 16 sequences, group 2 consists of 6 sequences, group 3 consists of 2 sequences, group 4 consists of 2 sequences. Based on these groups, it turns out that the China Wuhan sequence (sequence MT291826) is located in group 1 and other countries that are almost similar to the sequence in China Wuhan, namely the country of Timoe Leste with the sequence MT641766 also located in group 1.©2022 JNSMR UIN Walisongo. All rights reserved
Second kind Chebyshev collocation technique for Volterra-Fredholm fractional order integro-differential equations
Full text linkIn this work, we present the numerical solution of fractional order Volterra–Fredholm integro-differential equations using the second kind of Chebyshev collocation technique. First, we transformed the problem into a system of linear algebraic equations, which are then solved using matrix inversion to obtain the unknown constants. Furthermore, numerical examples are used to outline the method’s accuracy and efficiency using tables and figures. The results show that the method performed better in terms of improving accuracy and requiring less rigorous work.©2022 JNSMR UIN Walisongo. All rights reserved