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BERKALA SAINSTEK
Published by Universitas Jember
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Berkala SAINSTEK (BST) merupakan jurnal ilmiah yang memuat artikel hasil penelitian di bidang sains dan teknologi. Secara khusus BST diperuntukan bagi penulis internal mahasiswa Universitas Jember bidang fisika, matematika, biologi, kimia, teknik sipil, teknik mesin, teknik elektro dan sistem informasi. Namun BST juga menerima artikel dari penulis eksternal sepanjang memenuhi kriteria dan dalam lingkup bidang sains dan teknologi.
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Articles 254 Documents
Total Phenol and Antioxidant Activity of Ethanol Extract and Water Extract from Claw Uncariaa gambir Roxb Hartanti, Lucky; Ashari, Asri Mulya; Warsidah, Warsidah
BERKALA SAINSTEK Vol 9 No 3 (2021)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v9i3.27179

Abstract

Uncaria gambier Roxb is a plant from the Rubiaceae family, belongs to the Bajakah group and has been used empirically in the treatment of various types of diseases in the community. Besides being one of the industrial plants and export commodities produced in Sumatra and Kalimantan, gambier leaves is also used frequently in Indonesia, both for the pharmaceutical and cosmetic industries. As a result, market demand both nationally and internationally have increased. The aim of this research are determination of antioxidant activity of ethanol extract and aqueous extract of gambir claw using 1,1-diphenil-2-picrylhydrazyl (DPPH) and determination of total phenol using Calcetau folin reagent. Gambier plant samples were taken in the forest area around the Tanjungpura University campus, the claws were separated and dried at room temperature, then powdered and extracted by maceration using 70% ethanol pa and aquadest, then the extract was concentrated until it was ready to be tested for antioxidant activity and determination of total phenol. The total phenolic ethanol extract and aqueous extract of gambir claw were 224.66 mg GAE/g extract (GEA : Gallic Acid Eqivalent) and 299.08 mg GAE/g extract, respectively, while the antioxidant potential (IC50) was 39.566 μg/mL and 65.140 μg/mL, and the IC50 for comparison of Vitamin C was 7.02 μg/mL.
TiO2-rGO Composite for Photocatalytic Decolorization of Methylene Blue Under the Visible Light Illumination Hidayati, Ulfa Farizka; Aritonang, Anthoni B.; Destiarti, Lia
BERKALA SAINSTEK Vol 9 No 4 (2021)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v9i4.27602

Abstract

Titanium dioxide-reduced graphene oxide (TiO2-rGO) was synthesized by hydrothermal method using TiO2 powder and rGO precursor from graphite rod by modified Marcano Method. The obtained TiO2-rGO photocatalyst was characterized by X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), and Diffuse reflectance UV (DRUV). Based on XRD diffractogram, it is known that TiO2 has an anatase crystal phase. In the FTIR spectrum, it was observed that there was an absorption peak at the wavenumber of 1630 cm-1 from the vibration (C=C) as an indication that the C atom was incorporated into the TiO2 structure. The incorporation of C atoms into the TiO2 structure to form TiO2-rGO causes the bandgap energy to decrease from 3.29 eV to 3.20 eV. The photocatalytic activity was tested against decolorization of methylene blue solution for 180 minutes under visible light illumination from a 50 watt LED lamp. Every 10 minutes, absorbance was measured using a UV-Vis spectrophotometer at a wavelength of 664 nm. TiO2-rGO photocatalyst has better photocatalytic activity with %D of 96.39% under UV light and 84.32% under visible light illumination, while TiO2 is only able to degrade 93.87% and 36.55%, respectively.
Application of Black Scholes Method in Determining Agricultural Insurance Premium Based On Climate Index Using Historical Burn Analysis Method Sholiha, Aminatus; Fatekurohman, Mohamat; Tirta, I Made
BERKALA SAINSTEK Vol 9 No 3 (2021)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v9i3.22920

Abstract

Climate index insurance is an insurance that provides reimbursement for losses due to decreased harvest rates or crop failures caused by weather. The use of Historical Burn Analysis (HBA) method in determining climate index based on rainfall resulted in a concept of the agricultural insurance payment in Pasuruan Regency. The application of The Black Scholes method in determining agricultural insurance premiums is obtained when rainfall more than 17 mm the premium is Rp 221,234. If the rainfall are 13 mm ≥ RR < 17 mm, the nominal premium paid by farmers to the insurance party is Rp 147,489. Respondents in the study were farmers who owned rice fields. Instrument quality testing (questionnaire) using validity test and reliability test using the help of SPSS statistical software. It can be concluded that the questionnaire is valid and reliable. Based on the results of the questionnaire, farmers considered that the nominal agricultural insurance premiums are in accordance with farmers' income.
The Effect of Various Concentration BAP (6-Benzyl Amino Purine) on Orchid Growth (Macodes petola (Blume) Lindl.) In-Vitro Muchsin, Muchfa Eprilia; Supriatna, Ateng; Adawiyah, Ayuni; Darniwa, Adisty Virakawugi
BERKALA SAINSTEK Vol 10 No 1 (2022)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v10i1.27091

Abstract

Macodes petola (Blume) Lindl. has an attractive of leaves veins motif with letters pattern, so it has a high economic value. Tissue culture technique is reported as the best way of plant propagation in short time. BAP (6-Benzyl Amino Purine) has a role in stimulating shoot growth with a certain concentration. The purpose of this study was to determine the effect of Various Concentration BAP (6-Benzyl Amino Purine) on Orchid Growth (M petola (Blume) Lindl.) in vitro. This study used a completely randomized design (CRD) with 4 concentration BAP levels (0; 0.5; 1; 1.5 ppm) with 3 replication. Based on the results of the study, it showed that up to 60 DAP (Day After Planting) the composition of the media with a concentration of 0 ppm BAP had a higher average value for the increase in the stem height, number of shoots and number of roots, namely 1.77±0.798 cm, 2.4 ± 1,528 shoot and 2.4 ± 2,082 root. In contrast to the concentration of 1.5 ppm at this concentration it has a low average value the parameters of stem height, number of shoots and number of roots.
Groundwater Distribution and Potency in Faculty of Mathematics Natural Sciences, Universitas Jember based 3-Dimensional Resistivity Data Modelling Sari, Herlina Putri; Suprianto, Agus; Priyantari, Nurul
BERKALA SAINSTEK Vol 10 No 1 (2022)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v10i1.23025

Abstract

Lack of clean water when entering the dry season is a problem that often occurs in the FMIPA University of Jember. The purpose of this research is to know and estimate the potential distribution of the aquifer in the research area. 3D modeling of resistivity data was carried out using Voxler software. The input of resistivity data from the measurement results in the research area that the inversion process had carried out. The modeling results obtained an aquifer potency of 207.862,21 m3 or 21.63% of the total volume on the model image's cross-sectional map, with an irregular distribution pattern. Finally, using this method, the modeling of the aquifer potential volume and distribution can be estimated, and can be used as consideration in the use of groundwater in the Faculty of Mathematics and Natural Sciences, University of Jember.
Design of a Falling Ball Speed Measuring Instrument in Viscosity Experiment Using Arduino UNO ATmega Budiyono, B.; Sutrisno, Edy; Wibowo, Taufik Usman
BERKALA SAINSTEK Vol 10 No 1 (2022)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v10i1.27315

Abstract

Viscosity experiments in universities generally use falling ball method with manual observations. Measuring travel time of iron ball from one point to another manually using a stopwatch can cause a large error. This problem can be solved by designing a digital falling ball viscometer using infrared and photodiode configured with Arduino. Infrared and photodiode pairs are placed in the top and bottom glass tubes to detect the movement of iron ball so that it produces a change in voltage. This voltage change is used to mark start and stop times in time measurement. The time measurement obtained is then used to calculate speed of the ball through the formula for distance between sensors divided by time. Data obtained is then entered into viscosity formula of falling ball method to obtain viscosity value of fluid (oil). The digital falling ball viscometer is accurate when error obtained is less than 5%. The results obtained are the error of the digital viscometer measurement results are better than the error of the manual viscometer. The highest error obtained from the digital viscometer is 4%, while the lowest is 1%. This indicates that the digital falling ball viscometer has a high enough accuracy so that data obtained is in accordance with the reference and can be used as a viscosity experiment tool using falling ball method.
Inventory of Butterfly (Lepidoptera: Rhopalocera) at Agrotechno Park The University of Jember Purwatiningsih, P.; Anggreini, Widyantari; Setiawan, Rendy
BERKALA SAINSTEK Vol 10 No 1 (2022)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v10i1.20349

Abstract

The exploration of the butterfly on The University of Jember has been conducted. The objective of this study is to explore the diversity of butterfly on UPT Agrotechno Park The University of Jember. The research has been done during August to September 2020. Sampling was carried out by scanning methods in the fields with sweeping net. The results revealed the existence of 18 genus with four belonging to the families Papilionidae, Pieridae, Nymphalidae, and Lycaenidae. Moreover 24 species had been identified namely Papilio sp. 1, Papilio sp. 2, Troides sp., Graphium sp., Appias sp., Catopsilia sp., Delias sp. 1, Delias sp. 2, Eurema sp.1, Eurema sp. 2, Leptosia sp., Euthalia sp. 1, Euthlia sp. 2, Dophla sp., Elymnias sp., Euploea sp. 1, Euploea sp. 2, Hypolimnas sp., Junonia sp. 1, Junonia sp 2, Discophora sp., Acraea sp., Zizina sp. dan Lampides sp. Butterflies use plants as host plants and food plants. High host plant diversity is directly proportional to the diversity of butterfly species. The UPT Agrotechnopark Universitas Jember has 1 hectare of land in which there are collections of fruit, vegetable, ornamental, medicinal and food plants. The high diversity of host and forage plants in the UPT Agrotechnopark is a good habitat for butterflies. However, identification to the species taxa are further needed.
The Pattern of Microwave Scattering by the Dielectric of Milks Nugroho, Agung Tjahjo; Sa’adah, Nurul; Cahyono, Bowo Eko
BERKALA SAINSTEK Vol 10 No 1 (2022)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v10i1.30155

Abstract

A microwave electric field scattering by a dielectric object had been developed to identify the type of a milk. A simple geometric tomographic system is applied. The milk is placed in a cylindrical tube and emitted with a microwave signal which is described in term of a harmonic function. The scattering field anywhere outside the cylinder is quantifed analitycaly in which the unknown coefecients of the analytic function are determined at the surface of the cylinder. Three different type of milks, whole milk, UHT, and skim milk are studied. The incident fields are scanned from 1 GHz to 20 GHz and the scattering fields due to the illumination are quantified in three different locations around the objects. The study shows that the scattering field pattern depent on the the type of the milk. The whole milk produces the lowes and highest magnitude of the scattering field at 2.4 GHz and 4.5 GHz respectively. These frequency points are higher that that produce by the UHT and skim milk.
Synthesis of Zeolite-NaY for Methane Adsorption Susanti, Indri; Wulandari, Siska Ayu; Rosdiana, Silvi Rosiva
BERKALA SAINSTEK Vol 10 No 2 (2022)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v10i2.31356

Abstract

This research aims to synthesize zeolite-NaY material which is then applied as an adsorbent for methane adsorption. Zeolite-NaY was synthesized by hydrothermal method and characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and isotherm adsorption-desorption N2 (BET). The characterization results showed that synthesized zeolite-NaY had a diffraction peak with the highest intensity at 2θ = 6° and its morphology showed octahedral crystals. Zeolite-NaY was then applied as an adsorbent for methane adsorption. The methane adsorption test on zeolite-NaY was carried out using the gravimetric method at temperature of 30 °C and pressure of 1 bar. The data was recorded of increasing time every 1 minute until constant. The adsorption test results showed that the methane adsorption capacity on the zeolite-NaY material was 0.436 % wt.
Proximate and Essential Macrominerals Analysis of Tembakul (Mudskipper) Fish Flour as a Food Source for Stunting Prevention Lestari, Desriani; Hartanti, Lucky; Sofiana, Mega Sari Juane; Yuliono, Agus; Kurniadi, Bambang
BERKALA SAINSTEK Vol 10 No 1 (2022)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v10i1.31030

Abstract

The main cause of stunting is due to inadequate food intake according to the needs for growth and development of children, or insufficient nutrition of pregnant women. The low nutritional intake of pregnant and lactating mothers as well as children under five years old who are still growing and developing is generally caused by the wrong diet. One of the efforts to prevent stunting from an early age is to search for several sources of animal source food containing protein, fat and macro essential minerals according to nutritional standards. The purpose of this study was to determine the proximate content including protein and fat nutrition, water content and ash content, as well as mineral content including calcium, iron and phosphorus, from Tembakul (mudskipper) fish flour as the main needs in the growth of children, during pregnancy and lactation. Protein analysis was carried out using the Kjeldahl method, and fat analysis by extraction using a non-polar solvent, while the determination of essential macro minerals calcium and iron was carried out using an Atomic Absorption Spectrophotometer, and phosphorus analysis using ultraviolet spectrophotometry. The proximate content of Tembakul (mudskipper) fish flour from the Mempawah mangrove ecosystem is fat content (1.80%), protein content (50.67%), water content (24.58%), and ash content (20.20%). Mudskipper fish flour contains 3 essential minerals, namely Calcium (2.15%), Phosphorus (2.50%) and Iron (270.26 ppm).