Garuda - Garba Rujukan Digital

Article Per Year (5 Year)

All

Jurnal Penelitian Saintek

saintek
Website

Published by Universitas Negeri Yogyakarta

ISSN : 14123991 EISSN : 25287036 DOI : 10.21831

Core Subject : Science,

Decision Sciences, Operations Research & Management

Arjuna Subject : -

Articles 286 Documents

4 5 6 7 8

THE EFFECT OF pH ON THE ADSORPTION OF MICRONUTRIENT CATIONS OF Ca 2+ AND K + BY SILICA FROM LAPINDO MUD Jaslin Ikhsan; Siti Sulastri; Erfan Priyambodo
Jurnal Penelitian Saintek Vol 20, No 1: April 2015
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

The aim of this research was to determine the effect of pH on the adsorption of micronu- trients of Ca 2+ and K . by silica from lapindo mud. Data were collected by the adsorption experiments, on which 3 grams of silica separated from Lapindo mudwere dissolved in 300 mL of 0.0001 or 0.001 M Ca + 2+ or K ., and stirred for 2 hours. The pH of suspension was varied and left for equilibrate for 2 hours, and a sample was taken and measured for free concentration of K + + .cation using Flame Atomic Emission Spectroscopy and of Ca using Atomic Absorption Spectroscopy (AAS). The pH ranges were from 3 to 10. Temperature o 30 C and contact time of 2 hours were maintained. The research showed that both cations were adsorbed in sigmoid curve, increased with increasing pH values. In entire ranges of observed pH, the percentage of cations adsorbed by silica was not different signiﬁ cantly. The adsorbent of silica formed silanol (SiOH) in water. The –OH groups of silica were protonated forming SiOH o at lower pH and deprotonated forming SiO¯ at higher pH. Wether Ca 2+ or K + 2 + . cations were bound to silica surfacesvia cation exchange reactions, on which Ca2+ or K + . exchanged H of SiOH using one charge of the cations, forming [SiO(CaO)] for Ca 2+ , and [SiO-K] for K

MULTI-METAL ADSORPTIONS Ag (I), Pb (II), Cr (III), Cu (II) AND Ni (II) ON HYBRID ETILENDIAMINO-SILICA FROM GREEN RICE DRINKS Dyah Purwaningsih
Jurnal Penelitian Saintek Vol 14, No 1: April 2009
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

A study on the adsorption characteristic of multi metals (Ag(I), Pb(II), Cr(III), Cu(II) and Ni(II) on silica gel (SG) and ethylenediamine-silica hybrid (ESH) which was produced from the prior research (Purwaningsih, 2007) has been completed. The adsorption of multi metals Ag(I), Pb(II), Cr(III), Cu(II) and Ni(II) was conducted in a batch system for one hour at variation of metal ion concentration. The adsorbed metal ion was calculated from the differences of metal ion concentration before and after based on the analysis with AAS method. From adsorption data, thermodynamic parameters including capacity, energy and equilibrium constant of adsorption were determined with a model of Langmuir isotherm adsorption The research showed that if compared to SG, the adsorption capacity of ESH for Ag(I), Cr(III) and Ni(II) was increased, while those for Cu(II) and Pb(II) was decreased. The energy of adsorption for the metal ions were relatively low for Ag(I), Pb(II), Cr(III), Cu(II) and Ni(II) which are 22,36; 22,70; 13,36; 23,45; and 13,90 kJ/mol, indicate that the interaction between ESH and the metal ions involved fisisorption for Cr(III) and Ni(II) and chemisorption for Ag (I), Pb(II) and Cu(II).

MEASUREMENT OF LONGSOR LAND VULNERABILITY AS A DIFFICULTY PLAN FOR RESOURCES IN RESOURCES Muhammad Nursa'ban; Sugiharyanto Sugiharyanto; Nurul Khotimah
Jurnal Penelitian Saintek Vol 15, No 1: April 2010
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

The objectives of this research are to: Investigating the level of landslide susceptibility and identifying the distribution of landslide susceptibility locations in Menoreh Mountains area. This is the explorative research. The subject of this research are Menoreh Mountains area in Bagelen, and Bener districts Purworejo regency, in addition to Samigaluh District in Kulonprogo Regency. Land units were chosen as the sample using the purposive area sampling technique. Thirty land units were obtained by overlay maps of slope, geology, and soil types. Data collecting was conducted with observation method and documentation to be analyzed by qualitative deskriptif. Findings shown that (I) the level of landslide susceptibility that is in four categories in Samigaluh and Bener districts are low, medium, high, and very high. While three categories were low, medium, and high clasified in Bagelen district. The distributions of low landslide susceptibility covered about 46.500.527,08 m2 (2 land units in Samigaluh, 3 land units in Bener, and 3 land units in Bagelen). The medium categories covered about 104480073,8 m2 (l land units in Samigaluh, 4 land units in Bener, and 7 land units in Bagelen). High categories covered about 67734399,31 m2 (each of district is 2 land units). The very high categories covered about 12228602,01 m2 (2 land units for both, Samigaluh and Bener District). Key words: landslide, susceptibility, mitigation, hazard, Menoreh

THE VULNERABILITY ANALYSIS OF FLOOD AND FLOOD DISASTER MANAGEMENT IN CODE WATERSHED, YOGYAKARTA - Nurhadi; Dyah Respati Suryo Sumunar; Nurul Khotimah
Jurnal Penelitian Saintek Vol 21, No 2: Oktober 2016
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

This study aims to determine: (1) the vulnerability of cold lava ﬂ ood disaster along the banks of the River Yogyakarta City Code, and (2) the direction of ﬂ ood disaster management cold lava along the banks of the River Code of Yogyakarta. Research carried out along the banks of the River Code that was in the city of Yogyakarta from May to October 2013. The study population is along the banks of the Code River in the area of the city of Yogyakarta. Samples were along the river bank area code affected and not affected by cold lava ﬂ ood. Data collected by the method of documentation, interviews, and ﬁ eld checks. The data analysis technique is quantitative analysis with tumpangsusun/ overlay parameters tiered ﬂ ood weighted using GIS. The results showed that: (1) The area on the banks of the River Code that have medium levels of vulnerability is ﬂ ooding the medium category and Gowongan Cokrodiningratan region, while the region with the vulnerability of ﬂ ood prone category is Sosromenduran region, Suryatmajan, Prawirodirjan, Keparakan, Brontokusuman, and Sorosutan, (2) Referral to the revitalization plan for ﬂ ood prevention Code River settlements to be more effective and safer from disasters, namely through the revitalization of the vertical and horizontal.

DEVELOPMENT OF RESEARCH METHODS SPESI CR (VI) USING PRAKONCENTRATION TECHNIQUES BASED ON INJECTION ANALYSIS OF FLOW Sulistyani Sulistyani
Jurnal Penelitian Saintek Vol 17, No 1: April 2012
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

Penelitian ini bertujuan untuk mengetahui kinerja metode prakonsentrasi spesi renik Cr(VI) secara non-kromatografi berbasis analisis injeksi alir (FIA) dengan teknik deteksi spektrofotometri fasa padat. Analisis sampel menggunakan kolom XAD-4 dengan aqua DM sebagai pembawa dan aseton sebagai eluen. Pengukuran spektrofotometri pada panjang gelombang 540 nm. Kondisi optimum pH kompleks Cr(VI)-DPC maupun pH retensi XAD terhadap Cr(VI)-DPC adalah 1. Kapasitas retensi XAD-4 pada penelitian ini adalah 0,12 mg Cr/ g XAD. Kajian parameter analitik menunjukkan bahwa kinerja metode ini cukup baik. Nilai presisi yang dinyatakan sebagai koefisien variasi kurang dari 5% pada konsentrasi renik (ppb). Kepekaan dari metode ini mencapai konsentrasi 0,77 ppb dan limit deteksi mencapai 4,5 ppb. Daerah linier dari konsentrasi diperoleh antara 40 ppb sampai 80 ppb dengan koefisien relasi 0,997. Nilai pemekatan (EF) dari prakonsentrasi dengan metode ini mencapai 14 kali. Dari hasil aplikasi metode, diperoleh konsentrasi spesi Cr(VI) yang terdapat dalam sampel air dari lingkungan industri pertambangan adalah masing-masing 2,67 ppm dan 1,38 ppm. Kata kunci: prakonsentrasi, Cr(VI), XAD, DPC, FIA

THE USE OF AJAX TECHNOLOGY IN NEW STUDENTS REGISTRATION WEBSITE AT MATANA UNIVERSITY Himawan Himawan; Ignatius Joko Dewanto; Muhammad Ghurfata Rumara
Jurnal Penelitian Saintek Vol 22, No 2: Oktober 2017
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

Formerly, website technology only used HTML to display static content (web 1.0), then in the modern era, modern website was developed (web 2.0). The use of HTML language was combined with dynamic web programming languages such as PHP, ASP.Net, and JSP. However, in order to make the website page become more interactive and responsive, the use of dynamic web programming languages was not enough, therefore a technology that called as AJAX was created. This application is able to make website page becomes more responsive and interactive. The use of AJAX technology in modern website applications can also make the website page load faster and save the bandwidth usage of the internet network connection due to the asynchronous data transfer process between the client and the server. This study was aimed to fi nd out the mechanism of data transfer process and the comparison 99 of access speed level between client computer and the server (web and database server), especially on the website page using AJAX technology. This study used case study method and literature review analysis. Through this research, the AJAX engine model contained in JavaScript programming can be analyzed to produce better level of connectivity between client computers and the server.

ACTIVITY OF SITOTOKSIK ETANOL EXTRACT PLANT GROWTH (Cynometra ramiflora Linn) ON HEAVY CELL, T47D and WiDR Haryoto Haryoto; Muhtadi Muhtadi; Peni Indrayudha; Tanti Azizah; Andi Suhendi
Jurnal Penelitian Saintek Vol 18, No 2: Oktober 2013
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

Cynometra ramifolia Linn is known as Sala plant. This plant, especially in Solo City categorized as rare plant and traditionaly used to cure uric acid, diabetes, hypertension, and others pain. It is interesting to know the other activities by done the test for human cancer cell-lines. This research objective to identify the cytotoxicity effects of ethanol extract from C.ramiflora the stem bark and leaves against T47D, HeLa and WiDr cancer cell lines. The cytotoxicity test of ethanol extract from C.ramiflora the stem bark and leaves determined by MTT assay by calculating the level of IC50 which was based on the percentage of the cell death following the 24 hours incubation with the extract. The results showed that ethanol extract of stem bark has cytotoxic effect to HeLa, T47D and WiDr cell-lines with the IC50 of 1000; 0,90 and 6,29 g/mL respectively. The leave cytotoxic effect to HeLa, T47D and WiDr cell-lines with the IC50 of 1,92; 6,37 and 0,41 g/mL respectively. This research indicated that the ethanol extract isolated from C. Ramiflora leaves a selective cytotoxicity effect to WiDr cell line.

ISOLATION AND IDENTIFICATION OF SECONDARY METABOLIT COMPOUNDS IN ETIL ASETIC FRACTIONS ON MINDI LEAF Nurul Lutfia; Sri Atun
Jurnal Penelitian Saintek Vol 23, No 2: Oktober 2018
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

This study was aimed at isolating and identifying secondary metabolites contained in the ethyl acetate fraction of parasitic leaves (Dendrophthoe falcata (L.f)) Ettingsh which attaches to the stem of Mindi plants (Melia azedarach). The subjects in this study were leaves of parasitic plants on Mindi plants. While the objects in this study were secondary metabolites from the ethyl acetate fraction of the leaves of parasite plants attached to the mindi plant. The research method was carried out by extracting macerated leaves of D. falcata with ethanol solvents. The ethanol extract obtained was partitioned using n-hexane, chloroform, and ethyl acetate. Ethyl acetate fraction was separated by gravity column chromatography (CCG). The relatively non-polar fraction that has shown a single stain is tested for purity using 3 different types of solvents and identified using UV-Vis, IR, and GC-MS. The results showed that the compounds that could be isolated and identified from the relatively non-polar ethyl acetate fraction of D. falcata leaves were stigmast-5-en-3β-ol with an abundance of 6.49%, having a molecular weight of m / z 414 with base peak 55. Compounds sterols are compounds commonly found in parasitic plantsISOLASI DAN IDENTIFIKASI SENYAWA METABOLIT SEKUNDER PADA FRAKSI ETIL ASETAT DAUN MINDIPenelitian ini bertujuan untuk mengisolasi dan mengidentifikasi senyawa metabolit sekunder yang terdapat dalam fraksi etil asetat daun benalu (Dendrophthoe falcata (L.f)) Ettingsh yang menempel pada batang tumbuhan Mindi (Melia azedarach). Subjek dalam penelitian ini adalah daun tumbuhan benalu pada tanaman mindi. Sedangkan objek dalam penelitian ini adalah senyawa metabolit sekunder dari fraksi etil asetat daun tumbuhan benalu yang menempel pada tanaman mindi. Metode penelitian dilakukan dengan ekstraksi maserasi daun D. falcata dengan pelarut etanol. Ekstrak etanol yang diperoleh dipartisi menggunakan n-heksana, kloroform, dan etil asetat. Fraksi etil asetat dipisahkan secara kromatografi kolom gravitasi (KKG). Fraksi relatif non polar yang sudah menunjukkan noda tunggal diuji kemurniannya menggunakan 3 jenis pelarut yang berbeda dan diidentifikasi menggunakan UV-Vis, IR, dan GC-MS. Hasil penelitian menunjukkan senyawa yang dapat diisolasi dan diidentifikasi dari fraksi etil asetat relatif nonpolar daun D. falcata adalah stigmast-5-en-3β-ol dengan kelimpahan 6,49 %, memiliki berat molekul m/z 414 dengan base peak 55. Senyawa sterol merupakan senyawa yag lazim ditemukan dalam tumbuhan benalu.

ENERGY USE PERFORMANCE IN THE BUILDING COOLING SYSTEM USING A TERMOSTAT CONTROL, ON / OFF DIGITAL AND FUZZY LOGIC Henry Nasution
Jurnal Penelitian Saintek Vol 16, No 2: Oktober 2011
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

In this study, an alternative solution to reduce energy consumption in building airconditioning system is proposed and introduced. The operation and energy consumption of the system operated as either with the new control system or with the traditional on/off control were compared. Measurements were taken during the experimental period at a time interval of one minute for a set point temperature of 22 and 23o C. The room temperature, energy consumption and energy-saving ware analyzed. The main objective is to determine the amount of energy saved when a digital on/off and fuzzy logic controller is applied to the air-conditioning system. The experimental results show that significant energy savings of approximately 24 to 43% for digital on/off and 48 to 73% for fuzzy logic control were obtained. The results also indicated that the digital on/off and fuzzy logic control can save energy and improve indoor comfort significantly for building AC system compared to the thermostat control technique.

THE EFFECT OF BLADE NUMBER AND WATER VELOCITY TOWARD THE PERFORMANCE OF HELIKS GORLOV TURBINE Jeri Pranio; Karnowo Karnowo
Jurnal Penelitian Saintek Vol 24, No 2: Oktober 2019
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

This study was aimed at determining the influence of the number of blades and water velocity on the performance of vertical axis water turbine type Helical Gorlov. The method used was an experimental method. The descriptive analysis method was also used to analyze the data. The data obtained were in the form of variations of blades number and water velocity. The variations in the number of blades used were 2 blades, 3 blades, and 4 blades. While water velocity variations used were 0.81 m / s, 0.94 m / s, 1.08 m / s, and 1.18 m / s. The parameters were used to measure the amount of current and voltage produced by the multimeter and the number of rotations per minute (rpm) of the turbine produced by the tachometer. The results show that the number of blades and water velocity affected the performance of the Gorlov helical water turbine. The most optimal Gorlov helical turbine based on the results of research with the highest power coefficient (Cp) value is a turbine with 2 blades at a water velocity of 0.94 m/s which produces a Cp value of 0.00376 and a TSR value of 1.35.PENGARUH JUMLAH SUDU DAN KECEPATAN AIR TERHADAP KINERJA TURBIN AIR SUMBU VERTIKAL TIPE HELIKS GORLOVPenelitian ini bertujuan untuk pengaruh jumlah sudu dan kecepatan air terhadap kinerja turbin air sumbu vertikal tipe Heliks Gorlov. Metode yang digunakan dalam penelitian ini adalah eksperimen. Penelitian ini menggunakan analisis deskriptif.Data yang duperoleh berupa variasi jumlah sudu dan variasi kecepatan air. Variasi jumlah sudu yang digunakan adalah 2 sudu, 3 sudu, dan 4 sudu. Variasi kecepatan air yang digunakan yaitu 0,81 m/s, 0,94 m/s, 1,08 m/s, dan 1,18 m/s. Parameter dalam penelitian ini yang digunakan untuk menentukan kinerja adalah mengukur besarnya arus dan tegangan yang dihasilkan multimeter dan banyaknya rotasi per menit (rpm) dari turbin yang dihasilkan tachometer.Hasil penelitian menunjukkan bahwa jumlah sudu dan kecepatan air mempengaruhi kinerja turbin air heliks gorlov. Kedua, kecepatan air mempengaruhi kinerja turbin air heliks gorlov.Turbin heliks Gorlov paling optimal berdasarkan hasil penelitian dengan nilai koefisien daya (Cp) tertinggi yaitu turbin dengan 2 sudu pada kecepatan air 0,94 m/s yang menghasilkan nilai Cp sebesar 0,00376 dan nilai TSR 1,35.

Page 6 of 29 | Total Record : 286

4 5 6 7 8

Filter by Year

2001 2025

Filter By Issues

All Issue Vol 30, No 2 (2025) Vol 30, No 1 (2025) Vol 29, No 2 (2024) Vol 29, No 1 (2024) Vol 28, No 2 (2023) Vol 28, No 1 (2023) Vol 27, No 2 (2022) Vol 27, No 1 (2022) Vol 26, No 2 (2021) Vol 26, No 1 (2021) Vol 25, No 2 (2020) Vol 25, No 1 (2020) Vol 24, No 2: Oktober 2019 Vol 24, No 1: April 2019 Vol 23, No 1 (2018): April 2018 Vol 23, No 2: Oktober 2018 Vol 22, No 2: Oktober 2017 Vol 22, No 1: April 2017 Vol 21, No 2: Oktober 2016 Vol 21, No 1: April 2016 Vol 20, No 2: Oktober 2015 Vol 20, No 1: April 2015 Vol 19, No 2: Oktober 2014 Vol 19, No 1: April 2014 Vol 18, No 2: Oktober 2013 Vol 18, No 1: April 2013 Vol 17, No 1: April 2012 Vol 16, No 2: Oktober 2011 Vol 16, No 1: April 2011 Vol 15, No 2: Oktober 2010 Vol 15, No 1: April 2010 Vol 14, No 1: April 2009 Vol 13, No 1: April 2008 Vol 12, No 2: Oktober 2007 Vol 12, No 1: April 2007 Vol 11, No 1: April 2006 Vol 10, No 2: Oktober 2005 Vol 10, No 1: April 2005 Vol 9, No 1: April 2004 Vol 8, No 2: Oktober 2003 Vol 8, No 1: April 2003 Vol 7, No 2: Oktober 2002 Vol 7, No 1: April 2002 Vol 6, No 1: Saintek 2001 More Issue

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Kab. sleman,

Daerah istimewa yogyakarta

INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name -

Contact Email -

Phone -

Journal Mail Official -

Editorial Address -

Location Kab. sleman, Daerah istimewa yogyakarta INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Kab. sleman,

Daerah istimewa yogyakarta

INDONESIA