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All Journal JPMS (Jurnal Pendidikan Matematika dan Sains) INOTEKS : Jurnal Inovasi Ilmu Pengetahuan, Teknologi, dan Seni Jurnal MEKANIKAL REAKTOR TEKNIK JURNAL KESEHATAN LINGKUNGAN INDONESIA MIMBAR: Jurnal Sosial dan Pembangunan Jurnal Agripet Jurnal Rekayasa Kimia & Lingkungan Jurnal Sains Materi Indonesia JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Majalah Kedokteran Bandung Jurnal Kebijakan Kesehatan Indonesia Jurnal Sains Dasar English Language Teaching Abdimas Language Circle : Journal of Language and Literature Students´ Journal of Economic and Management Jurnal Online Mahasiswa (JOM) Bidang Keguruan dan Ilmu Pendidikan MAJALAH ILMIAH WIDYA PALASTREN JAM : Jurnal Aplikasi Manajemen Jurnal Paradigma SITEKIN: Jurnal Sains, Teknologi dan Industri Bulletin of Chemical Reaction Engineering & Catalysis Berkala Ilmu Kesehatan Kulit dan Kelamin Perspective Jurnal Pendidikan Bahasa Inggris Jurnal Kimia dan Kemasan Fakultas Ilmu Kesehatan Jurnal Ilmu Kelautan Spermonde Majalah Ilmiah MOMENTUM JURNAL KOLABORASI JURNAL OCTOPUS SMATIKA BULETIN FISIKA Jurnal Inspiration Jurnal Informatika IDEAS: Journal on English Language Teaching and Learning, Linguistics and Literature Terampil : Jurnal Pendidikan dan Pembelajaran Dasar Sistemasi: Jurnal Sistem Informasi Jurnal Mosharafa Paediatrica Indonesiana EDUCATIO : Journal of Education ISLAMIC COUNSELING: Jurnal Bimbingan Konseling Islam Script Journal: Journal of Linguistic and English Teaching Turbo : Jurnal Program Studi Teknik Mesin TADARUS Proceeding Simposium Nasional Kelautan dan Perikanan ELS Journal on Interdisciplinary Studies in Humanities Mesin Conference on Innovation and Application of Science and Technology (CIASTECH) Academic Journal Perspective : Education, Language, and Literature JKIP (Jurnal Keguruan dan Ilmu Pendidikan) Jurnal Respirologi Indonesia JURNAL PANGAN SAWERIGADING Arthavidya Jurnal Ilmiah Ekonomi Agroplantae: Jurnal Ilmiah Budidaya dan Pengelolaan Tanaman Perkebunan Jurnal Bisnis Terapan Menara Ilmu Jurnal Ilmu Manajemen dan Akuntansi Terapan (JIMAT) MMJ (Mahakam Midwifery Journal) Jurnal Ilmu Manajemen Indonesian Journal of Community Services JALL (Journal of Applied Linguistics and Literacy) Jurnal Ilmiah Permas: Jurnal Ilmiah STIKES Kendal Jurnal Teknologi Bahan dan Barang Teknik BERDAYA: Jurnal Pendidikan dan Pengabdian Kepada Masyarakat
Articles

RECOVERY GARAM LITHIUM DARI AIR ASIN (BRINE) DENGAN METODA PRESIPITASI Sumarno, Sumarno; Ratnawati, Ratnawati; A. Nugroho, A. Nugroho
TEKNIK Volume 33, Nomor 2, Tahun 2012
Publisher : Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (51.65 KB) | DOI: 10.14710/teknik.v33i2.4387

Abstract

Lithium demand increases as it is widely used as raw material for rechargeable battery, alloy for airplane, andfuel for fusion nuclear reactor. Lithium is an extremely reactive element, that it is never found as free element innature. Lithium compounds are found in earth crust, with very small concentration (20 ? 70 ppm) and totalcontent of more than 20 million tons. The biggest lithium reserve is in seawater (0,14 ? 0,25 ppm) andgeothermal water (7 ppm) with total amount of 230 billion tons. There is no industry applies the technology torecover lithium from seawater. Having a vast sea area and abundant geothermal sources, Indonesia needs todevelop a technology to recover lithium from both sources. This research is aimed to recover lithium fromgeothermal water. The experiment was conducted using synthetic and geothermal water with lithiumconcentration range of 220 ? 400 ppm, temperature range of 20 ? 40°C, and mixing time range of 1 ? 4 hours.The experiment was designed with 2 level factorial design. The results show that the most influencing variable ismixing time, while significant interaction amongst variables is not observed. Further experiment usinggeothermal water from Bledug Kuwu with initial lithium concentration of 400 ppm and temperature 30°Cresulted in optimum mixing time, i.e. 3 hours with 92,5% of the lithium could be recovered
PEMANFAATAN TANAMAN DI HALAMAN SEKOLAH DALAM PEMBELAJARAN ANATOMI TUMBUHAN DI SMA NEGERI BANTUL Surachman, Surachman; Ratnawati, Ratnawati
Jurnal Pendidikan Matematika dan Sains Vol 1, No 1: June 2013
Publisher : Faculty of Mathematics and Natural Sciences, Yogyakarta State University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21831/jpms.v1i1.12480

Abstract

Penelitian ini bertujuan untuk mengetahui 1) respon siswa dalam belajar anatomi tumbuhan meng-gunakan tanaman yang tumbuh di halaman sekolah, 2) nilai-nilai belajar yang berkembang pada siswa yang diperoleh sebagai efek pengiring dalam belajar anatomi tumbuhan, 3) ragam hambatan dan solusi yang dilakukan guru Biologi SMA Negeri Bantul dalam memanfaatkan  tanaman yang tumbuh di hala-man sekolah dalam pembelajaran anatomi tumbuhan. Jenis penelitian ini adalah penelitian eksploratif, dengan variabel yang diteliti berupa respon siswa dalam belajar anatomi tumbuhan, nilai-nilai belajar yang berkembang selama proses pembelajaran anatomi tumbuhan, dan ragam hambatan yang dialami guru Biologi SMA Negeri Bantul dalam memanfaatkan objek tanaman yang tersedia di halaman sekolah dalam pembelajaran anatomi tumbuhan. Subjek penelitiannya adalah satu kelas siswa Kelas XI SMA Negeri I Banguntapan, dan guru-guru Biologi SMA Kabupaten Bantul. Hasil penelitian menunjukkan bahwa pemanfaatan potensi tanaman di halaman sekolah dengan menggunakan panduan belajar berupa LKS direspon cukup baik oleh siswa, nilai-nilai afektif sebagai bentuk produk belajar berkembang cukup baik, dan hambatan guru dalam memanfaatkan potensi tanaman di halaman sekolah lebih banyak terjadi akibat kurang memadainya alat dan bahan belajar yang tersedia di sekolah.Kata kunci: anatomi tumbuhan, nilai-nilai belajar, ragam hambatan, objek biologi
THE QUALITY OF DOCUMENTS AND PREPARATION OF RPJMDES AFTER THE ESTABLISHMENT OF VILLAGE LAW Ratnawati, Ratnawati; Sulistyani, Ambar Teguh
MIMBAR (Jurnal Sosial dan Pembangunan) Vol 35, No 2 (2019): Vol 35, No 2 (2019): Volume 35, No. 1, Year 2019 [Accredited Sinta 2] No 10/E/K
Publisher : Universitas Islam Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29313/mimbar.v35i2.4126

Abstract

According to Law Number 6 of 2014 on Village  (Village Law), a village must have a Village Mid-Term Development Plan (abbreviated as RPJMDes) as one of the requirements for disbursing the village funds. This study is conducted to determine the quality of documents and the process of RPJMDes making by applying mixed methods, which is a combination of quantitative and qualitative methods. The study sites covered 4 (four) districts in the Special Region of Yogyakarta with 10 samples of villages from each district (40 villages on the whole). The results of this study show that the diversity in document quality and RPJMDes document preparation process caused by the ability of team 11 (11 formulators of the village mid-term development plan), the ability of village governments to direct and provide technical assistance and guidance, the presence or absence of the role of third parties (universities), as well as the interaction between villages in an effort to understand the scope and the contents of the RPJMDes.
NANOTECHNOLOGY AN EMERGING NEW TECHNOLOGY FOR INDONESIA PART I. NANOTECHNOLOGY IN GENERAL Ratnawati, Ratnawati; D.D. Anggoro, anggoro; G.A. Mansoori, G.A. Mansoori
Reaktor Volume 10 No. 1 Juni 2006
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/reaktor.10.1.46-53

Abstract

Nanotechnology is shortly defined as the ability to build micro and macro material and product with atomic precistion. Feynman is considered to be the scientist who put a strong foundation for the development of nanotechnology with his phenomenal speech in 1959 entitled "There's Plenty of Room at the Bottom - An invitation to enter a new field of physics." The invention of scanning tunneling microscope, followed by atomic force microscope, has enabled the world to see atoms and nolecules and opened more possibility for the scientists to develop nanotechnology. Other breakthough in nanotechnology is the discoveries of fullerene, carbon nanotube and diamondoids. Nanotechnology has found various fields of application, such as in biomedical , materials, aerospace, surface science and energy, to name a few, lead by the united States, Europe, and Japan, The technology brings benefits as well as risks to human life. Some of the risks are potentially global in scope. It is why a single, trustworthy, international administration holding controls on the technologyis is urgently needed.
PENGARUH PH DAN DOSIS NAOCL TERHADAP PENURUNAN KADAR COD DAN KLOR BEBAS PADA LIMBAH CAIR PRODUKSI MONOMER VINYL KLORIDA Ratnawati, Ratnawati; Yoshi, Linda Aliffia; Wibawa, Surya Aji
Jurnal Rekayasa Kimia & Lingkungan Vol 13, No 2 (2018): Jurnal Rekayasa Kimia & Lingkungan
Publisher : Chemical Engineering Department, Syiah Kuala University, Banda Aceh, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23955/rkl.v13i2.10947

Abstract

Limbah cair dari produksi monomer vinyl klorida merupakan limbah yang mempunyai kandungan Chemical Oxygen Demand (COD) yang tinggi yaitu sekitar 1000 ppm dan Biohemical Oxygen Demand (BOD) sekitar 500 ppm, sedangkan nilai maksimal standar baku mutu air buangan ke badan air adalah 250 ppm untuk COD dan 100 ppm untuk BOD. Penelitian ini bertujuan untuk mempelajari pengaruh pH dan dosis NaOCl terhadap penurunan COD dan kadar klor bebas serta untuk mendapatkan nilai pH dan dosis NaOCl yang optimal. Limbah cair produksi monomer vinyl klorida yang digunakan adalah limbah dari Pabrik X yang berada di Cilegon. Kadar COD yang tinggi disebabkan oleh kandungan senyawa Na(COOH) dalam limbah cair tersebut. Penurunkan nilai COD telah dilakukan dengan penambahan NaOCl yang merupakan salah satu produk dari Pabrik X tersebut sebesar 10 gam/jam pada pH 2, namun hasilnya belum memenuhi persyaratan. Pada penelitian ini digunakan variasi pH pada 2, 5 dan 8 serta dosis NaOCl yang ditambahkan sebesar 10, 20, 30, 40 dan 50 gram/jam dengan laju alir limbah cair yang diolah di unit pengolahan limbah cair tersebut sebesar 20 m3/jam. Parameter yang diukur dalam penelitian ini adalah kadar COD dan kadar klor bebas sebelum dan sesudah proses. Hasil penelitian menunjukkan bahwa pada pH 5 dengan dosis NaOCl 40 dan 50 gram/jam, proses ini memberikan hasil terbaik karena dapat menurunkan kadar COD dari 1034 sampai 190 dan 130 ppm (efisiensi penurunan 82,5 dan 87 %) dengan kadar klor bebas 0,8 dan 1 ppm yang telah memenuhi nilai baku mutu sesuai peraturan pemerintah.
TINGKAT KEPUASAN KONSUMEN TERHADAP KUALITAS DAN HARGA DAGING SAPI YANG DIJUAL DI KOTA BANDA ACEH Ratnawati, Ratnawati; Nurliana, Nurliana; Razali, Razali
Jurnal Agripet Vol 14, No 2 (2014): Volume 14, No. 2, Oktober 2014
Publisher : Agricultural Faculty

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17969/agripet.v14i2.1889

Abstract

(The level satisfaction of consumers to quality and price of beef in Banda Aceh)ABSTRACT. This study aims to determine level satisfaction of consumers to quality and price to beef sold in Banda Aceh, knowing influence of quality  and beef price to satisfaction of consumer and also know most dominant variable have an effect on to satisfaction of beef consumer  in Banda Aceh. The sampling methods is that used was purposive sampling is counted 180 consumers. The level of beef consumer satisfaction to sold in Banda Aceh is in the level of very low. The quality and  price to the satisfaction of consumers to beef sold in Banda Aceh has significant different to satisfaction of consumers P 0,05. The quality variable which significantly has a dominant of beef consumer satisfaction to sold in Banda Aceh. The value of determination coefficient (R Square) is equal to  0,31,9 show that quality and price of beef is influenced satisfaction of consumers is equal to 31,9 %, meanwhile 68,1% is influenced by other factors not included in this study. Concluded  that the quality and price have ability to influence satisfaction of consumers. The good quality can improve satisfaction of consumers and stiff price can degrade satisfaction of consumers.
ULTRASOUND-ASSISTED ULTRA-MILD-ACID HYDROLISIS OF -CARRAGEENAN Ratnawati, Ratnawati; Indriyani, Nita
Reaktor Volume 17 No. 4 Desember 2017
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (569.57 KB) | DOI: 10.14710/reaktor.17.4.191-196

Abstract

The low molecular weight fraction of ?-carrageenan is useful in biomedical applications. An ultrasound-assisted acid hydrolysis of ?-carrageenan has been studied. ?-carrageenan with an initial number-average molecular weight of 629 kDa was dispersed in distilled water to form a 5 g/l solution. The pH (3 and 6) of the solution was adjusted by adding HCl solution. The depolymerization reaction was carried out in an ultrasonic device at various temperatures (30, 40, 50, and 60°C) and times (8, 16, 24, and 32 min). The experimental results showed that ultrasound positively contributed to acid hydrolysis process. The number-average molecular weight of the treated k-carrageenan was lower or the percentage of reduction was higher at lower pH, longer reaction time, and higher temperature. The lowest number-average molecular weight (14 kDa) or the highest percent of molecular weight reduction reduction (97.7%) was achieved after ultrasonic irradiation at 60°C and pH 3 for 32 min. Keywords: depolymerization; midpoint scission; ultrasonication
IMPROVEMENT OF THE REDLICH-KWONG EQUATION OF STATE BY MODIFICATION OF CO-VOLUME PARAMETER Ratnawati, Ratnawati
Reaktor Volume 13, Nomor 1, Juni 2010
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (466.745 KB) | DOI: 10.14710/reaktor.13.1.58-65

Abstract

Cubic equations of state are widely used in phase-equilibrium calculations because of their simplicity and accuracy. Most equations of states are not accurate enough for predicting density of liquid and dense gas. A modification on the Redlich-Kwong (RK) equation of state is developed. Parameter b is modified by introducing a new parameter,b, which is a function of molecular weight and temperature. The modification gives a significant improvement over the original RK equation for predicting density. For 6538 data points of 27 compounds, the proposed equation gives only 2.8% of average absolute deviation (AAD), while the original RK and the Soave-Redlich-Kwong (SRK) equations give 11.4% and 11.7%, respectively. The proposed modification improves the performance of the RK equation for predicting vapor pressure as well. For 2829 data points of 94 compounds, the proposed modification lowers the AAD of the RK equation from 1460% down to 30.8%. It is comparable to the famous SRK equation, which give 5.8% of AAD. The advantage of the proposed equation is that it uses only critical pressure and temperature as other equations of states do, and molecular weight, which is easily calculated. Another advantage is that the proposed equation simpler than the SRK equation of state.
PERAN LABA MEMODERASI HUBUNGAN MODAL KERJA DAN BIAYA EKUITAS (Studi Kasus pada Perusahaan Manufaktur di Bursa Efek Indonesia) Ratnawati, Ratnawati
Students Journal of Economic and Management Vol 1, No 1 (2012): VOL. 1 NO. 1 EDISI PERTAMA 2012
Publisher : Students Journal of Economic and Management

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

Abstract

This study aimed to examine the effect of Nibe to Working Capital Gain and equity costs of case studies on the effects of manufacturing companies on Bursa Efek  Indonesia (BEI). The samples used in this research is a group of companies manufacturing the category of companies whose shares are actively traded on the Stock Exchange always during peeode observations (2007-2010). The number of samples obtained by category amounted to 19 companies over a period of 4 years. Secondary data was obtained from the Indonesia Stock excange (IDX) annual statistics for the period 2007 to 2010. The analysis used in this study is multiple regression techniques (multiple regression) to test the hypothesis t-test and F-test at the 5% level of significance (α = 0.05). Hypothesis test results indicate that the variable income and variable working capital Nibe together equally significant effect on the cost of equity. This result indicates that these two variables are jointly able to significantly influence the cost of equity. The test results also found that working capital and cost of equity has a negative and significant effect, because it has the value of the Standardized Beta Coefficiens 0000 0601 and its significance is greater than alpha (0.05). Keywords: Nibe earnings, working capital, cost of equity
PENERAPAN TEKNOLOGI FLUIDIZED BED DRYER DENGAN PENAMBAHAN ZEOLIT 3A UNTUK MENINGKATKAN EFISIENSIPENGERINGAN GABAH Hidayati, Noor; P., Utami Diah; Ratnawati, Ratnawati; Suherman, Suherman
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 2, Nomor 4, Tahun 2013
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Diponegoro,

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

Abstract

Now, drying paddy  using conventional method is irrelevant to used. The need of grain increasing each year is one of the main factor that pushes scientist to invent new methods of drying paddy grain. The old method is unusefull since it takes up space, needed the sun as the drying media which causes a long drying time. One of the alternative of drying paddy grain is by using mechanic dryer. By using this type of dryer, the process of drying takes faster comparing to the old method and the distribution of grain is supplied continuously. The dryer which uses fluidized bed  can be one of the solution due to its less energy consumption, a better drying result and high drying capacity. The variable used to identify drying performance is temperature and loading weight. From the experiment, it is resulted that the best temperature for drying paddy grain is 50 C with the flowrate 3,5 m/s.
Co-Authors A. Nugroho A. Nugroho A. Yoshi, Linda Abduh, Muhammad Saugi AGUS PURWANTO Ahmad Faizal ahmad yani Aji Prasetyaningrum Ambar Teguh Sulistyani, Ambar Teguh Amin Nugroho Andarini, Sita Laksmi Andinawati, Mia Andri Cahyo Kumoro anggoro D.D. Anggoro, anggoro Ansyari Mone, Ansyari Anwar, Asni Aprilina Purbasari Ari Pani Desvina Aryadi Suwono Bakti Jos Balik Sudarsana Batau, Haliah Budiwati Budiwati Cahyono, Erwin Budi Catarina Sri Budiyati Chifdillah, Nino Adib Damayanti, Triya Decy Lukitasari Dewi Ayuningtyas Diah Susetyo Retnowati Didih Faridah, Didih Dyah Hesti Wardhani Ekasari, Flora Elis Sofianti Enda Puspitasari Etika Rachmawati, Etika Faisal Yunus Fitria Fitria Frista, Rhoito Fuad, Muhammad Ulil G.A. Mansoori G.A. Mansoori, G.A. Mansoori Hargono Hargono Hartati Tamti, Hartati Hartono, Damin Henry, R L Inderiati, Sitti - Indriyani, Nita Irma Andriani Isbaniah, Fathiyah Isma, Hikma Nurul Iyus Hendrawan Johannes Leonard Joko Wahyu Wibowo Jumali Jumali K., Zaenal Kunda, Asri Kusumaningtyas, Dyah Arum L. Buchori Latukau, Hasni Lestari, Novi Dian Lilies Youlia Friatin, Lilies Youlia Linda Aliffia Yoshi, Linda Aliffia Livana Ph, Livana Lusito, Lusito M. A. Graciafernandy M. Zen Rahfiludin Maelasari, Rika Mappamiring Mappamiring Mappangara, Suriadi Martha Irene Kartasurya Marzuki Ukkas, Marzuki Mochammad Djaeni Mohamad Djaeni Morton, J Muhajirin Muhajirin Mulyadi, Deny Muhamad nanang nanang Nguyen, V Ningsih, Ririn Astuty Noerhidayati, Elly Noor Hidayati Nugraha, Cahyarani Daulika Nurfiningsih, Nurfiningsih Nurkhikmah, Eli NURLIANA NURLIANA Nurrrahmi, Maftuhah Nurul Asiah Perak Samosir Prasetyo, Dian Estu Pujiati, Tri Rahma Ayu Maharani Ramdhani, Eka Chandra Rappe, Rohani Ambo- Razali Razali Reski Praminasari, Reski Rita Kartika Sari Rohayati Arifin, Rohayati Rokhman, M.Taufiq Noor Rosmiaty Rosmiaty Salim, Amir Samoedro, Erlang Samudro, H.M Septiani, Hemas Septiani, Mimin Setyorini Setyorini Silalahi, Oberlin Since, Since Singgih Hartanto Siti Thomas Zulaikhah Slamet Slamet Soehardiman, Dicky Souisa, Felda Suarniati, Ni Wayan Sugeng, Purwito Suhandoyo Suhandoyo, Suhandoyo Suherman Suherman Sulastri Sulastri Sulastri, Neng Sumarno Sumarno Sumirna, Sumirna Sungkawati, Endang Surachman Surachman Suratsih Suratsih Suryani Yuliyanti, Suryani Suseno, Purbo Tarwana, Wawan Tavip Dwi Wahyuni, Tavip Dwi Thomas, P S Tiala, Fabia Trisnawati, Pemi Utami Diah P. Utami, Kurniati Dwi Wenny Pebrianti Wibawa, Surya Aji Widayat Widayat Wiratno Wiratno Y., Andri Yenny Widianty, Yenny Yudhy Dharmawan Yustina Linasari Zulkifli N