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Design of Student and Course Learning Outcomes Measurement Kristianto, Hans; Prasetyo, Susiana; Susanti, Ratna Frida; Adithia, Mariskha Tri
JPI (Jurnal Pendidikan Indonesia) Vol 10, No 1 (2021)
Publisher : Lembaga Penelitian dan Pengabdian kepada Masyarakat

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (369.27 KB) | DOI: 10.23887/jpi-undiksha.v10i1.29061

Abstract

Measurement of the outcomes becomes a vital part in OBE system to ensure the attainment of each outcome. In Indonesia, OBE was adopted in 2015 for higher education level. However, the changes were not accompanied with clear method to measure the outcomes, which became the urgency of this research. In this study, a preliminary method to measure student learning outcomes (SLO) and course learning outcomes (CLO) was presented. The measurement of SLO and CLO attainment was started by SLO mapping to courses, which usually had been done at curriculum design. Based on the mapping, formulation of CLO with a set of direct assessment was planned at the start of each course. After the teaching learning activities, a series of calculation was designed to obtain the attainment of SLO and CLO for each student, course, and whole study program. In the same time the final mark for GPA calculation of each student could also be obtained. The designed method could play an essential part in teaching-learning quality assurance and curriculum continuous improvement, which is aligned with both international and national accreditation criteria and standards. Furthermore, this study could provide insight for other study program in SLO and CLO attainment measurement.
Ekstraksi Batang Physalis Angulata dengan Air Subkritik Ratna Frida Susanti; Sartika Garini; Ignatius Jeremy Renaldo; Rachel Ananda; Ashanty Stenny
Research Report - Engineering Science Vol. 2 (2013)
Publisher : Universitas Katolik Parahyangan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1369.261 KB)

Abstract

Physalis angulata adalah jenis tanaman obat yang dikenal dalam pengobatan tradisional sejak zaman dahulu. Secara klinis, tanaman ini terbukti memiliki banyak kandungan bioaktif. Dalam pengobatan tradisional, masyarakat merebus semua bagian dari tanaman ini dan kemudian diambil airnya untuk diminum. Pada penelitian ini, batang physalis angulata adalah bagian yang diteliti untuk diekstrak dengan menggunakan air subkritik. Meskipun terbukti bahwa physalis angulata memiliki banyak kandungan bioaktif, belum ada penelitian yang detail tentang cara ekstraksi tanaman ini. Kebanyakan ekstrak diambil dengan menggunakan pelarut organik (methanol, ethanol) dengan menggunakan metode maserasi.Air dalam kondisi biasa yang merupakan pelarut polar, ternyata bersifat kurang polar pada suhu dan tekanan tinggi dan bisa diatur kepolarannya menyerupai pelarut organik dengan mengubah suhu dan tekanannya. Sehingga keunikan air ini digunakan dalam ekstraksi yang disebut subcritical water extraction atau pressurized water extraction (ekstraksi dengan fluida subkritik). Pada penelitian ini, batang physalis angulata diekstrak dengan menggunakan metode ekstraksi subkritik. Variabel yang diteliti adalah suhu, tekanan dan waktu reaksi. Ekstrak yang diperoleh dianalisis kandungannya dan diuji aktivitas antioksidannya dengan metode DPPH. Penelitian ini diharapkan menjadi penelitian awal untuk menguji keefektifan metode ekstraksi subkritik untuk mengambil komponen bioaktif dari physalis angulata.
Pengaruh Jenis, Konsentrasi Bahan Pengisi dan Suhu Pengeringan Terhadap Kualitas Ekstrak Buah Physalis Angulata Yang Diperoleh dengan Ekstraksi Menggunakan Air Subkritik Ratna Frida Susanti; Arenst Andreas; Garry Christianto Solihin
Research Report - Engineering Science Vol. 2 (2015)
Publisher : Universitas Katolik Parahyangan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (716.336 KB)

Abstract

Penggunaan ekstrak alami dari tumbuhan semakin luas dikembangkan dalam bidang farmasi. Keinginan masyarakat untuk kembali ke produk alam dan minimnya efek sampingyang ditimbulkan menjadi dua dari beberapa alasan yang muncul. Physalis angulata atau dikenal dengan nama ceplukan adalah tumbuhan herbal yang hidup semusim dan seringditemui tumbuh secara liar di beberapa daerah di Indonesia. Physalis angulata digunakan secara luas dalam pengobatan tradisional. Dalam pengobatan tradisional, masyarakat merebussemua bagian dari tanaman ini dan kemudian diambil airnya untuk diminum. Akan tetapi berdasarkan studi terdahulu, penggunaan air pada suhu didihnya kurang efektif dalammengekstrak tanaman ini. Oleh karena itu, dipilihlah pelarut berupa air pada kondisi subkritiknya (suhu diatas titik didih air sampai dengan dibawah suhu kritik, pada tekanan tinggi), karena air pada kondisi subkritik memiliki kemampuan mengekstrak menyerupai pelarut organik yang notabene dihindari pemakaiannya karena sifatnya yang toksik, karsinogenik dan mahal. Ekstrak yang diperoleh dengan menggunakan air subkritik pada suhu 250o C memiliki aktivitas antioksidan yang tinggi akan tetapi memiliki bentuk yang berminyak dan padat. Sehingga untuk membentuk sediaan obat dalam bentuk bubuk diperlukan tambahan bahan pengisi (filler) pada proses pengeringan ekstrak.Tujuan khusus yang ingin dicapai dalam penelitian ini adalah (i) mempelajari pengaruh jenis bahan pengisi pada kualitas ekstrak physalis angulata (ii) mempelajari pengaruh konsentrasi bahan pengisi pada kualitas ekstrak dan (iii) mempelajari efek suhu pengeringan pada pengeringan dengan menggunakan oven vakum.Target akhir dari penelitian ini adalah diperolehnya sediaan obat berbentuk bubuk dari ekstrak buah physalis angulata dengan kondisi pengeringan yang tepat untuk mempertahankan kandungan antioksidan di dalamnya. Metodeyang digunakan adalah dengan ekstraksi menggunakan pelarut berupa air subkritik dan pengeringan ekstrak menggunakan oven vakum.Hasil penelitian menunjukkan dalam range penelitian ini, semakin besar konsentrasi filler dan suhu pengeringan oven maka semakin baik nilai total fenol, flavonoid dan aktivitasantioksidannya. Filler aerosil terbukti lebih bagus dalam mempertahankan kualitas antioksidan dalam ekstrak.
Pengaruh Penambahan Filler dan Suhu Pengeringan terhadap Kandungan Antioksidan pada Daun Physalis angulata yang Diperoleh dengan Ekstraksi Menggunakan Air Subkritik Ratna Frida Susanti; Dessy Natalia
Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2016: Prosiding SNTKK 2016
Publisher : Seminar Nasional Teknik Kimia Kejuangan

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Abstract

Physalis angulata or ceplukan is a wild plant, typically grows in rice field, forest or yard. Before the planting season, farmers typically exterminate those plants. However, it was well known in folk medicine having bioactive compounds which can cure several diseases such as asthma, hypertension, boil etc. In this research, Physalis angulata extract can be obtained by extraction using subcritical water. Subcritical water was chosen as a solvent because it is nontoxic; abundant with adjustable polarity so can replace the toxic organic solvents such as methanol, ethanol, acetone etc.The objective of this research is to study the effect of filler type and concentration along with drying temperature to the total phenol, flavonoid and IC50 in Physalis angulata leaves extract. Filler was added to absorb water and make the powder form of extract. Two kinds of fillers were used, aerosil and microcrystalline cellulose (MCC). The concentration of filler was varied from 0-30 wt% for MCC and 0-15 wt% for aerosil. The oven drying temperature was varied from 40-60 oC. The results show that an addition of filler improved the total phenol, flavonoid and antioxidant activity.The higher the concentration of filler, the better the total phenol, flavanoid and antioxidant activity.In the presence of filler, the total phenol improved by 5.5  folds for addition of 30 wt% MCC and 3.3 folds for 15 wt% aerosil at drying temperature of 60oC. Total flavonoid improved by 7.6 folds for addition of 30 wt% MCC and 7.3 folds for 15 wt% aerosil above the same drying temperature. The higherdrying temperature leaded to shorter drying time which can protect antioxidant from deterioration.
Studi Kinetika Proses Atmospheric Pressure Acid Leaching Bijih Laterit Limonit Menggunakan Larutan Asam Nitrat Konsentrasi Rendah Kevin Cleary Wanta; Felisha Hapsari Tanujaya; Ratna Frida Susanti; Himawan Tri Bayu Murti Petrus; Indra Perdana; Widi Astuti
Jurnal Rekayasa Proses Vol 12, No 2 (2018)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (671.213 KB) | DOI: 10.22146/jrekpros.35644

Abstract

A B S T R A C TKinetics study of atmospheric pressure acid leaching (APAL) process is indispensable for extractor design in an industrial scale. So far, the kinetic model used for this process is the shrinking core model. In this study, the shrinking core model was evaluated against experimental data for laterite leaching process using a solution of low concentration nitric acid (0.1 M). Variations in temperature and particle size were carried out at 303–358 K and <75–250 microns. Other operating conditions, such as pulp density, stirring speed, and time were kept at 20% w/v, 200 rpm, and 120 minutes, respectively. The model evaluation results showed that the shrinking core model was not suitable for this process because the process controlling stage is not just one stage only.Keywords: kinetics; laterite; leaching; shrinking core.A B S T R A KStudi terkait kinetika proses atmospheric pressure acid leaching (APAL) sangat diperlukan untuk proses perancangan ekstraktor dalam skala industri. Selama ini, model kinetika yang digunakan untuk proses tersebut adalah model shrinking core. Dalam studi ini, model shrinking core dievaluasi terhadap data percobaan proses leaching bijih laterit dengan menggunakan larutan asam nitrat konsentrasi rendah, 0,1 M. Variasi suhu dan ukuran partikel dilakukan pada 303–358 K dan <75–250 mikron. Kondisi operasi lainnya, seperti densitas pulp, kecepatan pengadukan, dan lama proses dijaga tetap pada 20%b/v, 200 rpm, dan 120 menit, secara berurutan. Hasil evaluasi model menunjukkan bahwa model shrinking core tidak cocok untuk proses ini karena tahapan pengendali proses tidak hanya satu tahapan saja.Kata kunci: kinetika; laterit; leaching; shrinking core
Pengaruh Derajat Keasaman (pH) dalam Proses Presipitasi Hidroksida Selektif Ion Logam dari Larutan Ekstrak Spent Catalyst Kevin Cleary Wanta; Federick Dwi Putra; Ratna Frida Susanti; Gelar Panji Gemilar; Widi Astuti; Shinta Virdhian; Himawan Tri Bayu Murti Petrus
Jurnal Rekayasa Proses Vol 13, No 2 (2019)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (642.593 KB) | DOI: 10.22146/jrekpros.44007

Abstract

A B S T R A C TNickel hydroxide [Ni(OH)2] is an important compound in producing rechargeable batteries. The synthesis of Ni(OH)2 can be carried out using a hydroxide precipitation method from a solution containing nickel (II) (Ni2+) ions. In this study, the synthesis of Ni(OH)2 was investigated from the solution of extracted spent catalyst using sulfuric acid (H2SO4) solution. The selective precipitation was conducted using sodium hydroxide (NaOH) solution and the degree of acidity (pH) was varied in the range of 4–14. The operating temperature was kept constant at 30oC. The experimental results showed that the optimum precipitation conditions of Al3+ and Ni2+ ions were obtained at different pH where the optimum pH values were 6 and 10, respectively. Precipitate samples were characterized and the results showed that the purity of Ni(OH)2 in those samples was 13.1%. The XRD results indicated that the structure of precipitate still contains other impurities, such as Na2SO4, Al(OH)3 and those compounds were mutually agglomerate.A B S T R A KNikel hidroksida [Ni(OH)2] merupakan senyawa penting dalam produksi baterai yang dapat didaur ulang. Sintesis senyawa Ni(OH)2 dapat dilakukan melalui metode presipitasi hidroksida dari suatu larutan yang mengandung ion nikel (II) (Ni2+). Pada studi ini, sintesis Ni(OH)2 dilakukan dari larutan induk hasil ekstraksi spent catalyst dengan menggunakan larutan asam sulfat (H2SO4). Proses presipitasi selektif dilakukan dengan menggunakan larutan natrium hidroksida (NaOH) dan derajat keasaman (pH) divariasikan pada kisaran 4 hingga 14. Temperatur operasi dijaga konstan pada 30 oC. Hasil percobaan menunjukkan bahwa proses presipitasi ion Al3+ dan ion Ni2+ mencapai keadaan optimum pada pH yang berbeda dengan nilai pH optimumnya adalah 6 dan 10, secara berurutan. Hasil karakterisasi sampel menunjukkan bahwa kemurnian Ni(OH)2 dalam sampel sebesar 13,1%. Hasil pengujian XRD mengindikasikan bahwa struktur presipitat yang terbentuk masih mengandung senyawa pengotor lain, seperti senyawa Na2SO4, Al(OH)3 dan senyawa–senyawa tersebut saling mengaglomerasi. 
Effect of Surfactant Type on Synthesis and Characteristics of Nanonickel Hydroxide Kevin Cleary Wanta; Stephen Lim; Ratna Frida Susanti; Gelar Panji Gemilar; Widi Astuti; Himawan Tri Bayu Murti Petrus
Jurnal Rekayasa Proses Vol 15, No 2 (2021)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.69723

Abstract

Nickel hydroxide has a vital role in various applications, especially as a support material for energy storage materials. Nickel hydroxide can be synthesized through the hydroxide precipitation method. However, the product formed by this method may be large or more than 100 nm because the agglomeration step can occur easily. This present work aims to study the effect of surfactant types in the synthesis and characterization of nickel hydroxide nanoparticle. Nickel sulfate (NiSO4) solution was used as a precursor solution, while 5M sodium hydroxide (NaOH) solution was used as a precipitation agent. The surfactants studied were alkyl benzene sulfonate (ABS), sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB), and polyvinylpyrrolidone (PVP). The nickel hydroxide synthesis process was carried out at 50 oC for 1 hour. The surfactant concentration used was at the critical micelle concentration (CMC), where the CMC for ABS, SDS, CTAB, and PVP were 0.01; 0.05; 3; and 0.5 %w/v, respectively. The synthesis of nickel hydroxide nanoparticle was carried out successfully precipitated almost 100% of Ni2+ ions. The product characterization that has been carried out shows that ABS surfactant produces the best nickel hydroxide nanoparticle product where the particle size is 3.12–4.47 nm.
Studi Kinetika Proses Atmospheric Pressure Acid Leaching Bijih Laterit Limonit Menggunakan Larutan Asam Nitrat Konsentrasi Rendah Kevin Cleary Wanta; Felisha Hapsari Tanujaya; Ratna Frida Susanti; Himawan Tri Bayu Murti Petrus; Indra Perdana; Widi Astuti
Jurnal Rekayasa Proses Vol 12, No 2 (2018)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (671.213 KB) | DOI: 10.22146/jrekpros.35644

Abstract

A B S T R A C TKinetics study of atmospheric pressure acid leaching (APAL) process is indispensable for extractor design in an industrial scale. So far, the kinetic model used for this process is the shrinking core model. In this study, the shrinking core model was evaluated against experimental data for laterite leaching process using a solution of low concentration nitric acid (0.1 M). Variations in temperature and particle size were carried out at 303–358 K and <75–250 microns. Other operating conditions, such as pulp density, stirring speed, and time were kept at 20% w/v, 200 rpm, and 120 minutes, respectively. The model evaluation results showed that the shrinking core model was not suitable for this process because the process controlling stage is not just one stage only.Keywords: kinetics; laterite; leaching; shrinking core.A B S T R A KStudi terkait kinetika proses atmospheric pressure acid leaching (APAL) sangat diperlukan untuk proses perancangan ekstraktor dalam skala industri. Selama ini, model kinetika yang digunakan untuk proses tersebut adalah model shrinking core. Dalam studi ini, model shrinking core dievaluasi terhadap data percobaan proses leaching bijih laterit dengan menggunakan larutan asam nitrat konsentrasi rendah, 0,1 M. Variasi suhu dan ukuran partikel dilakukan pada 303–358 K dan <75–250 mikron. Kondisi operasi lainnya, seperti densitas pulp, kecepatan pengadukan, dan lama proses dijaga tetap pada 20%b/v, 200 rpm, dan 120 menit, secara berurutan. Hasil evaluasi model menunjukkan bahwa model shrinking core tidak cocok untuk proses ini karena tahapan pengendali proses tidak hanya satu tahapan saja.Kata kunci: kinetika; laterit; leaching; shrinking core
Pengaruh Derajat Keasaman (pH) dalam Proses Presipitasi Hidroksida Selektif Ion Logam dari Larutan Ekstrak Spent Catalyst Kevin Cleary Wanta; Federick Dwi Putra; Ratna Frida Susanti; Gelar Panji Gemilar; Widi Astuti; Shinta Virdhian; Himawan Tri Bayu Murti Petrus
Jurnal Rekayasa Proses Vol 13, No 2 (2019)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (642.593 KB) | DOI: 10.22146/jrekpros.44007

Abstract

A B S T R A C TNickel hydroxide [Ni(OH)2] is an important compound in producing rechargeable batteries. The synthesis of Ni(OH)2 can be carried out using a hydroxide precipitation method from a solution containing nickel (II) (Ni2+) ions. In this study, the synthesis of Ni(OH)2 was investigated from the solution of extracted spent catalyst using sulfuric acid (H2SO4) solution. The selective precipitation was conducted using sodium hydroxide (NaOH) solution and the degree of acidity (pH) was varied in the range of 4–14. The operating temperature was kept constant at 30oC. The experimental results showed that the optimum precipitation conditions of Al3+ and Ni2+ ions were obtained at different pH where the optimum pH values were 6 and 10, respectively. Precipitate samples were characterized and the results showed that the purity of Ni(OH)2 in those samples was 13.1%. The XRD results indicated that the structure of precipitate still contains other impurities, such as Na2SO4, Al(OH)3 and those compounds were mutually agglomerate.A B S T R A KNikel hidroksida [Ni(OH)2] merupakan senyawa penting dalam produksi baterai yang dapat didaur ulang. Sintesis senyawa Ni(OH)2 dapat dilakukan melalui metode presipitasi hidroksida dari suatu larutan yang mengandung ion nikel (II) (Ni2+). Pada studi ini, sintesis Ni(OH)2 dilakukan dari larutan induk hasil ekstraksi spent catalyst dengan menggunakan larutan asam sulfat (H2SO4). Proses presipitasi selektif dilakukan dengan menggunakan larutan natrium hidroksida (NaOH) dan derajat keasaman (pH) divariasikan pada kisaran 4 hingga 14. Temperatur operasi dijaga konstan pada 30 oC. Hasil percobaan menunjukkan bahwa proses presipitasi ion Al3+ dan ion Ni2+ mencapai keadaan optimum pada pH yang berbeda dengan nilai pH optimumnya adalah 6 dan 10, secara berurutan. Hasil karakterisasi sampel menunjukkan bahwa kemurnian Ni(OH)2 dalam sampel sebesar 13,1%. Hasil pengujian XRD mengindikasikan bahwa struktur presipitat yang terbentuk masih mengandung senyawa pengotor lain, seperti senyawa Na2SO4, Al(OH)3 dan senyawa–senyawa tersebut saling mengaglomerasi. 
Effect of Surfactant Type on Synthesis and Characteristics of Nanonickel Hydroxide Kevin Cleary Wanta; Stephen Lim; Ratna Frida Susanti; Gelar Panji Gemilar; Widi Astuti; Himawan Tri Bayu Murti Petrus
Jurnal Rekayasa Proses Vol 15, No 2 (2021)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.69723

Abstract

Nickel hydroxide has a vital role in various applications, especially as a support material for energy storage materials. Nickel hydroxide can be synthesized through the hydroxide precipitation method. However, the product formed by this method may be large or more than 100 nm because the agglomeration step can occur easily. This present work aims to study the effect of surfactant types in the synthesis and characterization of nickel hydroxide nanoparticle. Nickel sulfate (NiSO4) solution was used as a precursor solution, while 5M sodium hydroxide (NaOH) solution was used as a precipitation agent. The surfactants studied were alkyl benzene sulfonate (ABS), sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB), and polyvinylpyrrolidone (PVP). The nickel hydroxide synthesis process was carried out at 50 oC for 1 hour. The surfactant concentration used was at the critical micelle concentration (CMC), where the CMC for ABS, SDS, CTAB, and PVP were 0.01; 0.05; 3; and 0.5 %w/v, respectively. The synthesis of nickel hydroxide nanoparticle was carried out successfully precipitated almost 100% of Ni2+ ions. The product characterization that has been carried out shows that ABS surfactant produces the best nickel hydroxide nanoparticle product where the particle size is 3.12–4.47 nm.