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All Journal Trikonomika: Jurnal Ekonomi Jurnal Sains dan Teknologi Reaksi QiST: Journal of Quran and Tafseer Studies
R Ridwan
Research Center for Biotechnology - Indonesian Institute of Sciences (LIPI)
Religion Humanities Chemical Engineering, Chemistry & Bioengineering Chemistry Economics, Econometrics & Finance Education Engineering Environmental Science Law, Crime, Criminology & Criminal Justice Materials Science & Nanotechnology Social Sciences Other

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Peranan Etika Kerja Islam Terhadap Hubungan Locus of Control dengan Kinerja Karyawan Ridwan, R
Jurnal Trikonomika Vol 12, No 1 (2013): Edisi Juni 2013
Publisher : Jurnal Trikonomika

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

This study’s objectives to asses moderating effect of Islamic work ethic variable to relationship in between locus of control with employers performance. The asses used Simple linear regression and Moderating Regression Analysis (MRA). Census method was used this study which included 32 responden from PT Bank Muamalat Indonesia Tbk. Cabang Palu employers. Result of the study indicated significantly effect of Islamic work ethic from relationship between locus of control to employers performance. Interaction coeficient marked negatif with significant ρ about 0.014 (ρ < 0.05) that it mind variable of islamic work ethic would be moderating variable which its fungtion diluted relationship locus of control to employers performance. Therefore, it need carefully to handle Islamic work ethic of employers if want to improve their performance by locus of control percieved.
ANALYSIS OF COAL QUALITY IMPROVEMENT USING CHEMICAL METHODS FOR MEETS STANDARDS OF CALORIFIC VALUE Nahar, N; Ridwan, R; Irwan, I; Pardi, P
Jurnal Sains dan Teknologi Reaksi Vol 22, No 01 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i01.5423

Abstract

As a country with relatively large coal resources and reserves, Indonesia will face challenges that are not easy in the future. The large amount of coal resources and reserves as well as the continuity of the coal mining industry cannot be ignored. Coal consumption in the world is expected to continue from time to time, especially in the Asian region. Lignite coal reserves account for around 48% of total coal reserves in the world, meanwhile in Asia lignite coal reserves reach 30%, while in Indonesia they reach 60% of total coal reserves. Although the amount of lignite coal consumed accounts for around 30% of total world coal production. The amount consumed in Asia accounts for only 10% of its total coal production. Especially in Indonesia, mining practices tend to tend to be higher quality bituminous and sub-bituminous coal which is more widely mined and produced because producing lignite coal is less economical and cannot meet market criteria. Thus, it can be predicted that what will remain in the future will be a large amount of lignite coal reserves that cannot be utilized. Because the opportunity to fill the potential of the coal market is still wide open, whether used directly as an energy source in power plants or exported abroad, promotion of the use of lignite coal must be made as early as possible as a very important issue for Indonesia. To improve the quality of lignite coal to coal whose quality is like that of anthracite coal so that it can be used, therefore it is necessary to have technology to improve the quality of lignite coal, so the Industrial Innovation Research research will improve the quality of coal using the stirring method by varying the influence of temperature and mixing time. coal, residual oil and kerosene can reduce the water content contained in low rank coal by the adsorption process. The research results show that operating conditions greatly influence the distribution of coal products. Relatively good operating conditions were obtained at a temperature of 200o C and a reaction time of 70 minutes with the results of: oil: 25 ml, water content: 0.668%, ash content: 11.883%, volatile matter: 30.122%, fixed carbon: 57.377%, and calorific value : 6581 Kcal/kg. Key words: Coal; Quality; Kerosene; Calorific Value; Enhancement
FORMULATION AND CHARACTERISTICS OF SOLID PERFUME FROM LEMONGRASS OIL WITH VARIATION BEESWAX AND ESSENTIAL OIL Yunus, Muhammad; Amalia, Zuhra; Ridwan, R; Aida, Atiqah; Ilmi, Awanis
Jurnal Sains dan Teknologi Reaksi Vol 22, No 02 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i02.6171

Abstract

ABSTRACT The potential availability of abundant essential oil plants in Indonesia is very beneficial for the community. One of the essential oil plants that can be utilized for its potential is citronella. Citronella oil can be formulated into solid perfume as an innovation to replace liquid perfume. This study aims to formulate and characterize solid perfume from various variations of beeswax concentration (30%, 40%, 50%), citronella (1%, 3%, 5%) and several note parfume. The solid perfume was characterized by observing the density value, boiling point value, organoleptic test and functional group test. The results showed that the highest density value of 0.9786 gr/ml and the melting point value of 69°C were in the 50% beeswax formulation and 1% citronella oil concentration. The lowest solid perfume density value of 0.9350 gr/ml and melting point value of 61°C were in the 30% beeswax formulation with 5% citronella oil concentration. FT-IR testing results, the solid perfume produced has the same functional groups in the mixture of raw materials made. This indicates that no new compounds are formed. The results of organoleptic testing show that solid perfume with 40% beeswax composition and 1% concentration is the most preferred. Keywords: Solid Perfume, Citronella Oil, Beeswax, Density
ANALYSIS OF COAL QUALITY IMPROVEMENT USING CHEMICAL METHODS FOR MEETS STANDARDS OF CALORIFIC VALUE Nahar, N; Ridwan, R; Irwan, I; Pardi, P
Jurnal Sains dan Teknologi Reaksi Vol 22, No 01 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i01.6331

Abstract

ABSTRACT As a country with relatively large coal resources and reserves, Indonesia will face challenges that are not easy in the future. The large amount of coal resources and reserves as well as the continuity of the coal mining industry cannot be ignored. Coal consumption in the world is expected to continue from time to time, especially in the Asian region. Lignite coal reserves account for around 48% of total coal reserves in the world, meanwhile in Asia lignite coal reserves reach 30%, while in Indonesia they reach 60% of total coal reserves. Although the amount of lignite coal consumed accounts for around 30% of total world coal production. The amount consumed in Asia accounts for only 10% of its total coal production. Especially in Indonesia, mining practices tend to tend to be higher quality bituminous and sub-bituminous coal which is more widely mined and produced because producing lignite coal is less economical and cannot meet market criteria. Thus, it can be predicted that what will remain in the future will be a large amount of lignite coal reserves that cannot be utilized. Because the opportunity to fill the potential of the coal market is still wide open, whether used directly as an energy source in power plants or exported abroad, promotion of the use of lignite coal must be made as early as possible as a very important issue for Indonesia. To improve the quality of lignite coal to coal whose quality is like that of anthracite coal so that it can be used, therefore it is necessary to have technology to improve the quality of lignite coal, so the Industrial Innovation Research research will improve the quality of coal using the stirring method by varying the influence of temperature and mixing time. coal, residual oil and kerosene can reduce the water content contained in low rank coal by the adsorption process. The research results show that operating conditions greatly influence the distribution of coal products. Relatively good operating conditions were obtained at a temperature of 200o C and a reaction time of 70 minutes with the results of: oil: 25 ml, water content: 0.668%, ash content: 11.883%, volatile matter: 30.122%, fixed carbon: 57.377%, and calorific value : 6581 Kcal/kg.Key words: Coal; Quality; Kerosene; Calorific Value; Enhancement
PRODUCTION OF BIODIESEL FROM JATROPHA FRUIT (Jatropha Curcas) Ridwan, R
Jurnal Sains dan Teknologi Reaksi Vol 22, No 02 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i02.6427

Abstract

ABSTRACT The energy crisis has led to rising petroleum prices. To address this issue, alternative fuels need to be sought. This study aims to utilize oil from the Jatropha plant (*Jatropha curcas*) to produce biodiesel through a transesterification reaction. The research was conducted using Jatropha oil-to-methanol ratios of 1:3, 1:4, and 1:5, with transesterification reaction times of 2 hours, 2.5 hours, and 3 hours. The results showed that the optimum volume of methyl ester from the transesterification reaction was achieved with a 1:4 ratio and a reaction time of about 2 hours.Keywords: Biodiesel, Jatropha plant, transesterification reaction
ANALISIS PENGENDALIAN KUALITAS PADA PEMBUATAN BIODIESEL DARI BUAH JARAK PAGAR (Jatropha curcas) DENGAN METODE TAGUCHI Ridwan, R
Jurnal Sains dan Teknologi Reaksi Vol 22, No 02 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i02.6359

Abstract

ABSTRAK Krisis energi menyebabkan harga minyak bumi semakin meningkat. Untuk mengatasi permasalahan tersebut, perlu dicari bahan bakar alternatif. Penelitian ini bertujuan memanfaatkan minyak tumbuhan Jarak (Jatropha curcas) untuk menghasilkan biodiesel melalui reaksi transesterifikasi. Kualitas merupakan faktor terpenting untuk mendapatkan kepuasan konsumen. Kualitas akan lebih baik apabila proses tersebut berjalan dengan konsisten. Metode Peta Kendali (Control Chart) digunakan untuk melihat keadaan dari proses produksi yang berjalan, kemudian dilakukan perbaikan melalui pendekatan metode Taguchi. Perbaikan berawal dari pemilihan faktor-faktor yang berpengaruh terhadap karateristik kualitas tersebut beserta nilai level, yang kemudian menjadi dasar dalam pemilihan Orthogonal Array. Hasil analisa diolah dengan menggunakan noise signal to ratio (SNR) dan analysis of variance. Berdasarkan penelitian tersebut didapat hasil bahwa setting level terbaik untuk faktor kendali yang berpengaruh terhadap kontribusi nilai flash point dari biodiesel sebesar 71,704 % adalah dengan pengaturan rasio minyak jarak dan solven 1 : 3 pada level 2. Keywords: Biodiesel, Tumbuhan Jarak, Metode Taguchi
PENGGUNAAN ROSIN UNTUK MENAMBAH KEKUATAN TARIK HASIL PEMUTIHAN ROTAN Ridwan, R
Jurnal Sains dan Teknologi Reaksi Vol 22, No 02 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i02.6400

Abstract

ABSTRAKPenelitian ini untuk mengetahui pengaruh penggunaan rosin dan alum terhadap sifat mekanik rotan. Variabel-variabel dari penelitian adalah konsentrasi rosin/alum dan temeperatur. Penelitian dilakukan dengan dua kali pengulangan untuk kekuatan tarik rotan. Hasil penelitian ini menunjukkan bahwa konsentrasi rosin dan alum memberikan pengaruh yang nyata terhadap kekuatan tarik rotan. Kekuatan tarik rotan cenderung bertambah dengan kenaikan konsentrasi rosin. Pada konsentrasi rosin/alum dengan perbandingan 1:3 memberikan hasil terbaik terhadap kekuatan tarik.Kata Kunci: pemutihan rotan, rosin, alum
PRODUCTION OF CHLORINE GAS (Cl2) AND SODIUM HYDROXIDE (NaOH) FROM THE PURIFICATION OF ACEH SALT: A Review Article Ridwan, R; Zaini, Halim
Jurnal Sains dan Teknologi Reaksi Vol 22, No 02 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i02.6361

Abstract

ABSTRACT Jangka salt contains NaCl, CaCl₂, MgCl₂, CaSO₄, MgSO₄, Na₂SO₄, H₂O, dust, soil, and fine sand, with NaCl content of less than 78%, categorizing it as low-quality salt. This salt can be refined to increase its NaCl content to 92%-100% through gradual physical and chemical purification processes, as well as using ion-exchange resin, resulting in high-quality salt. One of the advantages of high-quality salt is its use as a raw material for producing chlorine gas and sodium hydroxide through the electrolysis process. The results can be used in various industries for water treatment, soap production, plastics, paper manufacturing, and other chemical industries.Keywords: Chlorine gas, sodium hydroxide, salt, purification, electrolysis.
PERBAIKAN MUTU PADA PROSES PENGELOLAAN BENTONIT MURNI MENJADI BENTONIT NANO KOMPOSIT DENGAN MENGGUNAKAN METODE TAGUCHI Ridwan, R
Jurnal Sains dan Teknologi Reaksi Vol 22, No 02 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i02.6348

Abstract

ABSTRAK Usaha meningkatkan mutu bentonit nanokomposit menemui kendala yaitu cukup tingginya tingkat variasi mutu kekuatan uji tarik yang terjadi, sehingga dibutuhkan suatu penelitian terhadap faktor- faktor yang berpengaruh dan pengaturan komposisi bahan yang ideal untuk meminimalkan variasi mutu tersebut. Untuk menyelesaikan masalah tersebut digunakan metode Taguchi dalam perancangan eksperimen. Kelebihan metode ini ialah mampu meminimalkan akibat dari variasi terhadap respon serta eksperimen dapat dilakukan dengan efisien. Langkah yang dilaksanakan adalah memilih faktor-faktor kendali dan penentuan level - level yang dilanjutkan dengan membuat matrisk ortogonal. Analisa data dilakukan berdasarkan pengoptimalan analisa Mean,Anova dan Signal to Noise Ratio (SNR). Hasil yang diperoleh menunjukkan bahwa setting level terbaik untuk faktor kendali yang berpengaruh terhadap kestabilan kekuatan uji tarik bentonit nano komposit adalah pada ukuran bentonit 300 mesh pada level 3 dan suhu pemanasan 600C pada level 2.Keywords: Bentonit, kekuatan uji tarik, nano komposit, Taguchi.
PERANCANGAN ALAT PENJERNIHAN AIR GAMBUT MENJADI AIR BERSIH Putra, Alfian; Ridwan, R; Nasir, Muhammad
Jurnal Sains dan Teknologi Reaksi Vol 22, No 02 (2024): JURNAL SAINS DAN TEKNOLOGI REAKSI
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jstr.v22i02.6349

Abstract

ABSTRAKAlat penjernihan air gambut ini dirancang dengan menggunakan media filter yang terdiri dari kerikil yang berdiameter rata-rata 0,5-1,5 cm setebal 15 cm di bagian bawah, pasir dengan diameter rata-rata 0,2 mm – 0,4 mm setebal 70 cm di bagian tengah dan kerikil yang berdiameter rata-rata 0,5-1,5 cm setebal 15 cm di bagian atas dapat digunakan untuk menurunkan kesadahan, Total Dissolved Solid (TDS), menetralisasikan pH dan menjernihkan warna air gambut. Berdasarkan hasil analisa sampel yang telah diolah dengan alat penjernihan air gambut, efesiensi penurunan kesadahan sebesar 24,7%, Total Dissolved Solid (TDS) sebesar 9,76% dengan tanpa koagulan dan dengan menggunakan koagulan sebesar 74%. Untuk efesiensi penetralan pH air gambut dengan menggunakan koagulan sebesar 98,4% sedangkan tanpa menggunakan koagulan sebesar 96,4% sedangkan pada perubahan warna air gambut, dengan tanpa menggunakan koagulan warna kuning-kecoklatan berubah menjadi putih, dengan menggunakan koagulan warna kuning- keclokatan menjadi putih bening.Kata kunci : Air gambut, alat penjernih air gambut ,kesadahan ,TDS, pH.
Co-Authors Ahmed, Ishfaq Aida, Atiqah Alfian Putra Amalia, Zuhra Halim Zaini, Halim Ilmi, Awanis Irwan, I Muhammad Nasir Muhammad Yunus Mutaqin, Enjen Zaenal Nahar, N Naqiyah, N Pardi, P