Articles
Pengaruh Penambahan Polyethylene Glycol (PEG) Terhadap Sifat Magnetik (γ-Fe2O3) Yang Disintesis Dari Magnetit Batuan Besi (Fe3O4)
Ikhsan, Muhammad;
Puryanti, Dwi;
Budiman, Arif
Jurnal Ilmu Fisika Vol 9, No 2 (2017): Published in September 2017
Publisher : Universitas Andalas
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DOI: 10.25077/jif.9.2.103-109.2017
Telah dilakukan sintesis magnetit dari biji besi Nagari Surian Kecamatan Pantai Cermin Kabupaten Solok Sumatera Barat dengan metode kopresipitasi. Selanjutnya dari magnetit tersebut disintesis maghemit tanpa dan dengan penambahan PEG melalui oksidasi pada temperatur 400 oC selama 3 jam. Variasi PEG yang digunakan yaitu sampel tanpa penambahan PEG, sampel dengan penambahan PEG-2000, PEG-4000, dan PEG-6000. Maghemit yang dihasilkan dikarakterisasi sifat magnetik menggunakan Vibrating Sample magnetometer (VSM). Karakterisasi sifat magnetik menggunakan VSM menghasilkan nilai koersivitas berturut-turut yaitu 250 Oe, 193 Oe, 203 Oe, 178 Oe. Terlihat bahwa penambahan PEG mengurangi nilai koersivitas maghemit. Kata kunci: magnetit, maghemit, PEG, VSM, koersivitas
POLA PENAMPANG LINTANG MAKROSKOPIK TOTAL DALAM SEL BAHAN BAKAR NUKLIR
Aini, Nurul;
Shafii, Mohamad Ali;
Putra, Ardian
Jurnal Ilmu Fisika Vol 6, No 1 (2014): JURNAL ILMU FISIKA
Publisher : Jurnal Ilmu Fisika
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DOI: 10.25077/jif.6.1.25-30.2014
Penampang lintang makroskopik memiliki peranan penting dalam menghitung transport neutron yang terjadi pada reaktor nuklir. Hasil penampang lintang digunakan untuk menghitung nilai distribusi fluks neutron yang terjadi di teras reaktor. Penelitian ini menampilkan nilai penampang lintang makroskopik total dari sebuah sel bahan bakar nuklir. Tahap awal dilakukan dengan menentukan bahan bakar yang digunakan yaitu uranium-plutonium nitride, kemudian fraksi massa dan fraksi volume, cladding, dan pendingin. Perhitungan penampang lintang makroskopik ini dilakukan dengan metode simulasi komputer menggunakan bahasa pemrograman Borland Delphi 7.0. Program yang digunakan adalah program homogenisasi sel dengan data library JFS-3-J33 dari JAEA (Japan Atomic Energy Agency) yang menghasilkan nilai penampang lintang makroskopik total untuk 70 grup energi. Hasil analisis menunjukan bahwa pola penampang lintang makroskopik total untuk nuklida uranium dan plutonium pada energi tinggi (unresolved resonance) mengalami tumpang tindih (overlap) dalam sel bahan bakar nuklir.
Parents and Adolescents Pattern of Interpersonal Communication in The Restriction of Smartphone Usage
., Muslim
Journal of Humanities and Social Studies Vol 1, No 1 (2017): Journal of Humanities and Social Studies
Publisher : Lembaga Penelitian dan Pengabdian Nasyarakat Universitas Pakuan
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DOI: 10.33751/jhss.v1i1.374
Communication can be the media of proximity of parents and children. Parents will feel comfortable because they feel the child needs and love him. Conversely, the child will feel happy to get the attention of his parents. The development of communication technology led to a new style of communication style. Parent and child communication is no longer done face-to-face at the dinner table or in the living room. The role of interpersonal communication of parents and children began to shift since the presence of a smart tool that was created able to perform many activities.Communication patterns between adolescent boys and girls tend to be different Young men and women have different tendencies in smartphone use. Female teenagers are more dominant using social media to upload good photographs with friends or photos themselves. Young men use smartphones to play games, download songs, movies or video clips. Teenagers in Indonesia (40-50 percent) is a community of hp (smartphone) users. Teenagers use social media that includes instant messengers like LINE, Instagram, Twitter and other apps like Facebook, Youtube, Vlog and more. There are three patterns of communication that parents do in limiting the use of smartphones in adolescents. The patterns are Authoritarian communication patterns, Democratic communication patterns and Permissive Communication Patterns. Keywords: Communication Patterns, smartphones, restrictions
Studi Audit Delay Pada Perusahaan Manufaktur yang Go Public di Bursa Efek Indonesia
Rusdiyanto, Rusdiyanto
GEMA EKONOMI Vol 3 No 2 (2014)
Publisher : Fakultas Ekonomi Universitas Gresik
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DOI: 10.55129/.v3i2.227
Seiring dengan berkembangannya dunia usaha dalam era pasar bebas pihak manajemen perusahaan dituntut untuk berusaha memenuhi lebih banyak dana segar untuk keperluan operasionalnya. Salah satu cara untuk mengatasi kebutuhan dana segar tersebut adalah melalui pasar modal yaitu dengan menjual sahamnya di bursa efek.Untuk memudahkan penelitian di dalam pemecahan masalah yang telah dirumuskan variabel harus ditentukan dan diteliti sesuai masalah yang ada dan hubungan antar variabel, sehingga tidak menimbulkan interpretasi lain.Variabel yang digunakan dalam penelitian adalah audit delay sebagai variabel terikat, sedangkan variabel bebasnya adalah Leverage, Ukuran Perusahaan, dan Ukuran Kantor Akuntan Publik.Hasil pengujian dengan variabel tersebut terbukti kebenarannya dengan asumsi bahwa Kantor Akuntan Publik besar memiliki kemampuan untuk menyelesaikan proses audit lebih cepat dan mempunyai lebih banyak sumber daya daripada Kantor Akuntan Publik kecil.
PENGARUH PEMBERIAN INSENTIF TERHADAP PENINGKATAN PRODUKTIVITAS KERJA KARYAWAN PT PETROKOPINDO CIPTA SELARAS GRESIK
Suhardi, Suhardi
GEMA EKONOMI Vol 1 No 1 (2012)
Publisher : Fakultas Ekonomi Universitas Gresik
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DOI: 10.55129/.v1i1.261
Human resources are the labor force that is used to achieve optimal results in their work, meaning the output will be better achieved. Disarnping that when the ability of the dirniliki by an employee who can be taught to other labor and if it went well then the company will be able to more quickly growing.Relative to employee productivity problems: the problem of absenteeism has a huge influence. It also reflects the compliance / discipline of the employee, if an employee is absent continuously so that should receive the serious attention of the company, because if it is allowed will affect the morale of other employees who had always dutifully come to be undisciplined. Many ways by which companies to motivate employees to show better work than before, motivating tool is one of them is an incentive, the incentive is in addition to the revenue earned by the employee sebagar reward for work performance dicapainya.Tujuan this study was to determine whether the incentives have an effect on productivity and related work on PT Gresik Petrokopindo Copyright harmony.ÂÂÂÂÂ
MEMBANGUN STRATEGI PENGEMBANGAN FUEL CELL DI INDONESIA: Tinjauan Ringkas
hariyanto, hariyanto
185P -3466
Publisher : Agency for the Assessment and Application of Technology
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Teknologi fuel cell (sel bahan bakar) dewasa ini masih terus berkembang pesat dan disempurnakan. Hampir semua negara maju memberikan anggaran yang cukup besar untuk penelitian teknologi sel bahan bakar dari mulai pengembangan hingga proyek percontohan agar teknologi sel bahan bakar dapat segera memasuki ajang pasar komersial secepat mungkin. Dalam tulisan ini secara ringkas ditinjau pendekatan untuk penyusunan strategi pengembangan teknologi sel bahan bakar di Indonesia, khususnya terkait dengan peningkatan kerjasama antar pelaku peneliti dan pengembang sel bahan bakar di Indonesia. Beberapa pertimbangan awal yang bisa dijadikan dasar pada pengembangan sel bahan bakar di Indonesia a.l.: kemampuan sumber daya manusia, perkembangan teknologi material, ketersediaan sumberdaya alam, serta arah aplikasi yang tepat dan potensi pasar.
IN-SITU CO2 CURRENT EFFICIENCY MEASUREMENT OF DIRECT ETHANOL FUEL CELL
hariyanto, hariyanto
185P -3466
Publisher : Agency for the Assessment and Application of Technology
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In this present work, we carry out systematically study on catalyst for ethanol electrooxidation in direct ethanol fuel cell. For cathode catalyst we use a commercial catalyst of 40% Pt/C from ETEK. Catalysts were printed on to carbon paper of TGPH 060 and sandwiched into membrane electrode assembly (MEA) and then arranged in fuel cell with the geometric area 1.2 cm2. As an electrolyte, we used Nafion 117 from Du Pont. On-line Differential Electrochemical Mass Spectrometry (DEMS) measurement in fuel cell setup was carried out in order to determine the activity and selectivity which was indicated by result of Faradaic current and CO2 current efficiency of ethanol electro-oxidation respectively. PtRhCeO2/C was significantly improve the selectivity to form of CO2 in comparison to the commercial catalyst of 20% Pt/C from Alfa Aesar- Johnson Mattews . Increasing of selectivity is shown by increase of CO2 current efficiency of ethanol oxidation of about 25 percent in comparison to references catalyst of 20% Pt/C Alfa Aesar-JM
Pola Arus di Perairan Teluk Hurun Lampung Selatan
Riyadi, Agung
Jurnal Hidrosfir Indonesia Vol 2, No 2 (2007)
Publisher : Jurnal Hidrosfir Indonesia
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We observed the current data in Hurun Bay, South Lampung Sumatra Hurun Bay is a small semi enclosed bay with areas up to 1.5 km2 and has four mouth river. Measuremet field around one year from Januari 2003 until Januari 2004. The two current sensor located at central of the bay and the sensor take a depth about four (4) and twelve (12) meter from surface.The continous current record indicated that the current in Hurun Bay relative small. The current velocity at June is higher and have a average value 3.98 cm/second at 4 meter and 3.94 cm/second at 12 meter from surface and commonly current velocity in bay under 50 cm/second. Keywords: pattern flow, teluk hurun, current velocity
Model Transpor Penyebaran Sampah di Teluk Jakarta
Setiawan, Agus;
Riyadi, Agung
Jurnal Hidrosfir Indonesia Vol 2, No 3 (2007)
Publisher : Jurnal Hidrosfir Indonesia
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Spreading of wastes from 11 river mouths around the Jakarta Bay during the east and west monsoons is simulated in this study, making use of transport model. The data of wastes weight and concentration used in this study are obtained from “Marine and Jakarta Bay Wastes Prevention” pilot project conducted by the government of DKI Jakarta. In this simulation, it is assumed that the weight of daily outflow of wastes is constant and the composition of wastes is not taken into account.From the simulation results there are found that during the west monsoon, wastes in the Jakarta Bay mostly transported eastward, spread until 3 km and accumulated in the eastern part of the Jakarta Bay. Wastes with concentration more than 10 kg/L spread out to the offshore until 1 km from the shore line or river mouth. On the other hand, the wastes mostly transported westward during the east monsoon. These wastes spread westward until 5 km and mix with the wastes from the river mouths which are located in the western part of the Jakarta Bay. The amount of wastes which are spread westward during the east monsoon is greater than the amount of wastes which are spread eastward during the west monsoon.Keywords: Jakarta Bay, wastes, transport model
PENERAPAN TERUMBU KARANG BUATAN (RUMPON) DI PERAIRAN KUTAI KARTANEGARA KALIMANTAN TIMUR
Riyadi, Agung
Jurnal Hidrosfir Indonesia Vol 5, No 2 (2010)
Publisher : Jurnal Hidrosfir Indonesia
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Artificial reef (rumpon) are tools in the form fish collecting objects or structures that are designed made from natural or artificial materials that are placed permanently in marine waters. Many oil rigde spread in coastal area. Majority of fisherman from Kutai Kartanegara catch a fish around oil ridge and very dangerous. The Application of artificial reef technology as coral reefs have been set at Kutai Kartanegera waters in 2009. Activities are particularly in assessment site selection survey for deployment the artificial reef depand the quality and depth water. Artificial reef made of concrete with a total 60 pieces and has a size of 2 x 2.5 meters. The results of physical and chemical analysis such as water temperature, depth, salinity, turbidity, based material and dissolved oxygen in the normal condition. The dominat of sediment in a sand bed is muddy and has a marine topography a slope, because there is still considerable influence of the Mahakam delta. There are six potential locations for mooring artificial reef at position UTM 1.555000/9975100; 2.555823/9978221;3.559711/9981510;4.562515/9986117;5.558448/9991855; 6.557506/9987513. Artificial reef placement depths ranging 15 - 25 meters.