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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 6 Documents
Search results for , issue "Vol 9 No 4 (2021)" : 6 Documents clear
Prevalence of Phenylthiocarbamide (PTC) Taste Sensitivity and Colour Blindness in Tengger Tribe Population, Ranupani Village, Senduro, Lumajang Oktarianti, Rike; Putra, Iguh Widigda; Arofa, Resmining Mega; Lelono, Asmoro
BERKALA SAINSTEK Vol 9 No 4 (2021)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v9i4.26435

Abstract

The taste of sensitivity of phenylthiocarbamide (PTC), is autosomal dominant trait inherited while the colour blindness is a sex linked genetic trait on the X chromosome. The purpose of this study was to determine the distribution of taster and non taster phenotypes, prevalence of color blindness, frequency of taster and non taster alleles, and frequency of color blind alleles, as well as pedigree analysis in non taster and color blind families. The research was conducted on the Tengger tribe, in Ranupani village, Senduro, Lumajang. Determination of the sample is carryout randomly. Detection of the ability to taste PTC was respondents to taste the PTC solution from the lowest concentration of 0.32mg/L (P13) to the highest concentration of 1300 mg/L (P1). Color blindness detection by the Ishihara method. The results of the study showed that the distribution of the taster was 98.1% while the non-taster was 1.9%. The allele frequency of the dominant taster (T) was 0.86 and the recessive allele non taster (t) is 0.14. The prevalence of color blindness in the population of the Tengger tribe was 0.63% and the allele frequency for color blindness was 0.013. The pedigree analysis of non taster family showed that non taster individuals were born from taster couple (Tt) or from couple of non taster (tt) with tasters (Tt) heterozigot. While the pattern of inheritance of color blindness was criss-cross inheritance pattern, which is passed from mother to son.
The Assessment of Climate Change Impact on Meteorological Draught Susceptability on Sampean Watershed Ratih, Masita; Halik, Gusfan; Wiyono, Retno Utami Agung
BERKALA SAINSTEK Vol 9 No 4 (2021)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v9i4.25065

Abstract

Drought disasters that occur in the Sampean watershed from time to time have increased, both the intensity of events and the area affected by drought. The general objective of this research is to develop an assessment method for the impact of climate chan ge on vulnerability to drought disasters based on atmospheric circulation data. The specific objectives of this study are to model rainfall predictions based on atmospheric circulation data, predict rainfall in various climate change scenarios (Intergovernm ental Panel on Climate Change, IPCC – AR5), and assess vulnerability to drought disasters using a meteorological approach. The Standardized Precipitation Index (SPI) is one way to analyze the drought index in an area which was developed previous researcher. The Standardized Precipitation Index (SPI) is designed to quantitatively determine the rainfall deficit with various time scales. The advantage of the Standardized Precipitation Index (SPI) is that it is enough to use monthly rainfall data to compare drou ght levels between regions even with different climate types. To facilitate the presentation of the data base on the identification of d rought susceptibility, we need a system that can assist in building, storing, managing and displaying geographically ref erenced information in the form of spatial mapping. This research facilitates monitoring of the area of drought-prone areas, predicts drought levels, prevents future drought disasters, and prepares plans for rebuilding drought-prone areas in the Sampean watershed.
Analysis The Effect of Coconut Shell Charcoal Mixed Doses and Adhesive In Characteristics Jamu Dregs Briquettes Arafah, Arinda Dwi; Harsono, Soni Sisbudi
BERKALA SAINSTEK Vol 9 No 4 (2021)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v9i4.27326

Abstract

Briquette is an alternative simple fuel that has a relatively high calorific value, so it has the potential to reduce the use of firewood and fuel oil (BBM). Herbal waste is one of the biomass materials that came from the rest of the material in the production of herbal medicine made from medicinal plants. Utilization of herbal dregs as briquettes has been implemented by PT. Industri Jamu dan Farmasi Sido Muncul. Tbk, as fuel for boiler engines. Making briquettes from biomass requires the addition of materials, one of which is coconut shell charcoal and adhesives such as molasses and tapioca flour to improve the physical properties of the briquettes. Briquettes with good quality have a maximum moisture content and ash content of 8%, a heating value of more than 5000 cal/gram, a constant combustion temperature of 350℃ for a long period of time and is easily flammable. The purpose of this study was to determine the characteristics of briquettes based on the value of water content, ash content, combustion temperature, combustion rate, and calorific value. Variable treatment with the addition of coconut shell charcoal with several doses of 10%, 20%, and 30% and variations of adhesive materials. Data analysis was performed by using two-factor ANOVA statistical test. The results showed that briquettes with tapioca flour adhesive and 30% coconut shell charcoal composition had the best characteristics of briquettes compared to other variations.
Morphology and Economic Value of Macadamia (Macadamia integrifolia Maiden and Betche) Widiastuti, Ayu Vanisa; Asyiah, Iis Nur; Pujiastuti, P.
BERKALA SAINSTEK Vol 9 No 4 (2021)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v9i4.23380

Abstract

Macadamia has a scientific name Macadamia integrifolia Maiden and Betche from the Proteaceae family. The Macadamia plant habitat is in highland areas with an altitude of 1000 masl with a temperature of ≤ 32˚C. Macadamia plants are perennials with tough stems, and the branching is visible (monopodial). The purpose of this study was to determine the morphological characteristics of Macadamia plants and their economic value. The research was conducted at PTPN XII Sempol Plantation, Bondowoso with descriptive-qualitative method. The results of morphological observations showed that macadamia fruit is a dry fruit, indehiscent (when ripe the skin/shell does not break), similar to the type of achene fruit but the shell is thick and hard. Woody stems (lignosus) with monopodial branching type, incomplete leaves consisting of stalks and leaf blades, leaf blades are oblong-elongated, incised independently, pinnate leaf bones, phyllotaxis opposite crosswise. Macadamia trees can produce round fruit of about 20-70 kg per year with a monthly profit of Rp. 8,905,500. The economic potential of the Macadamia plant is very promising, as evidenced by the ongoing import of peeled macadamia with a volume of 6,862 kilograms worth US$ 145,100 (approximately Rp 1.9 billion) or Rp 291,405.29 per kilogram.
Decomposition Rate of Avicennia lanata in Bakau Kecil Mangrove Forest Area, Mempawah District Ashari, Asri Mulya; Warsidah, W.
BERKALA SAINSTEK Vol 9 No 4 (2021)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v9i4.27198

Abstract

Avicenna lanata is a type of mangrove that dominates the Mempawah Kecil Mangrove Forest. As many as 10 bacterial genera were identified from station 1 which is close to the influence of sea water, and 8 bacterial genera from station 2 which are close to residential areas. This study aims to determine the rate of decomposition of A. lanata leaf litter with 4 observation time periods with an interval of 15 days, namely the 15th, 30th, 45th and 60th days. The observations show that the rate of decomposition of the litter on the 15th day of observation is higher. Namely 0.206 gram/day at station I and 0.19 gram/day at station II, while the lowest rate of decomposition of litter occurred on the 60th day of observation, namely 0.112 gram/day at station I and 0.106 gram/day at station II. In addition, the parameters of physical and chemical of the environment such as DO, temperature, pH and salinity are in the range of their optimum values.
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.

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