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KAJIAN MINERAL SERPENTIN : KORELASI KARBONDIOKSIDA DAN PLATINUM GROUP ELEMENT (PGE) PADA SEQUEN BATUAN ULTRAMAFIK Tonggiroh, Adi; ., Purwanto
978-979-127255-0
Publisher : PROSIDING HASIL PENELITIAN FAKULTAS TEKNIK

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Abstract

Karbondioksida pada batuan ultramafik dapat merupakan proses karbonasi terurainya mineral olivin dalam kondisi alkalin dan membentuk magnesium karbonat, calcium karbonat. Jejak karbondioksida,serpentin dan magnesium dijumpai mengikuti bentuk rongga atau rekahan seperti pipih, tabular dan umumnya tidak beraturan. Penelitian ini berdasarkan pada ciri lapangan dari alterasi olivin, piroksen, magnesit, kalsit, magnesium oksida dan silika.Serpentinisasi terdapat pada rekahan batuan ultramafik dan berbentuk tabular, fragmental, juga menunjukkan perubahan warna putih kecoklatan, abu-abukecoklatan, abu-abu kehijauan, hijau pucat. Ciri lapangan tersebut, diduga erat kaitannya dengan proses karbonasi dan PGE. Penelitian ini mengkaji kehadiran magnesium oksida,air dan karbonisasi dengan metode SEM dan sayatan tipis pada batuan harzburgit. Hasil penelitian diketahui bahwa dalam rongga batuan karbonasi mengendap membentuk sodium bicarbonate (NaHCO3), sodium chlorid (NaCl) dan air yang bercampur dengan mineral reaktan seperti olivin (Mg2SiO4) atau serpentin (Mg3Si2O5).
Potential Nitrification and Nitrogen Mineral of Soil in Coffee Agroforestry System with Various Shading Trees ., Purwanto; Handayanto, Eko; Suprayogo, Didik; Bako Baon, John; Hairiah, Kurniatun
Pelita Perkebunan (Coffee and Cocoa Research Journal) Vol 23, No 1 (2007)
Publisher : Indonesian Coffee and Cocoa Research Institute

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Abstract

The role of shading trees in coffee farms has been well understood to establish suitable condition for the growth of coffee trees, on the other hand their role in nitrogen cycle in coffee farming is not yet well understood. The objectives of this study are to investigate the influence of various legume shading trees on the concentration of soil mineral N (N-NH4 + and N-NO3-), potential nitrification and to study the controlling factors of nitrification under field conditions. This field explorative research was carried out in Sumberjaya, West Lampung. Twelve observation plots covered four land use systems (LUS), i.e. 1) Coffee agroforestry with Gliricidiasepium as shade trees; 2) Coffee agroforestry with Gliricidiaas shade trees and Arachis pintoias cover crops; 3)Coffee agroforestry with Paraserianthes falcataria as shade trees; and 4) Mixed/multistrata coffee agroforestry with Gliricidiaand other fruit crops as shade trees. Measurements of soil mineral-N concentration were carried out every three weeks for three months. Results showed that shade tree species in coffee agroforestry significantly affected concentrations of soil NH4 +, NO3- and potential nitrification. Mixed coffee agroforestry had the highest NH4+/N-mineral ratio (7.16%) and the lowest potential nitrification (0.13 mg NO2-kg-1 hour -1 ) compared to other coffee agroforestry systems using single species of leguminous shade trees. Ratio of NH4 + /N-mineral increased 0.8—21% while potential nitrification decreased 55—79% in mixed coffee agroforestry compared to coffee agroforestry with Gliricidia or P. falcatariaas shade trees. Coffee agroforestry with P. falcatariaas shade trees had potential nitrification 53% lower and ratio of NH4 + /N-mineral concentration 20% higher than that with Gliricidia. Coffee agroforestry with P. falcataria as shade trees also had organic C content 17% higher, total N 40% higher, available P 112% higher than that with Gliricidia. The presence of A. pintoiin coffee agroforestry with Gliricidiareduced 56% potential nitrification but increased 19.3% of NH4+/N-mineral concentration. The low soil potential nitrification in the mixed coffee agroforestry had close relationship with the high content of soil organic matter. Key words : Nitrogen-mineral, nitrification, shading trees, agroforestry, Coffea canephora, nitrate, organic matter, intercropping,Gliricidia sepium, Arachis pintoi, Paraserianthes falcataria.
ANALISIS PENGARUH STRES KERJA DAN KONFLIK KERJA TERHADAP SEMANGAT KERJA PEGAWAI DENGAN KEPEMIMPINAN SEBAGAI VARIABEL MODERASI PADA PERUSAHAAN DAERAH AIR MINUM KABUPATEN PONOROGO Julaika, Siti; Farida, Umi; ., Purwanto
ISOQUANT : Jurnal Ekonomi, Manajemen dan Akuntansi Vol 1, No 1 (2017): Oktober
Publisher : Universitas Muhammadiyah Ponorogo

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Abstract

Penelitian ini dilatar belakangi oleh adanya penurunan semangat kerja pada Perusahaan Daerah Air Minum Kabupaten Ponorogo. Penelitian ini bertujuan untuk mengetahui pengaruh Stres Kerja dan Konflik Kerja terhadap Semangat Kerja Pegawai dengan Kepemimpinan Sebagai Variabel Moderasi pada Perusahaan Daerah Air Minum Kabupaten Ponorogo.Pengumpulan data dalam penelitian ini dengan metode kuesioner terhadap 99 responden yaitu seluruh pegawai pada Perusahaan Daerah Air Minum Kabupaten Ponorogo. Teknik analisis data yang digunakan adalah analisa regresi linear sederhada dan Moderated Regression Analysis (MRA) yang berfungsi untuk membuktikan hipotesis penelitian.Hasil penelitian menunjukkan bahwa 1).Variabel Stres Kerja mempunyai pengaruh yang positif dan signifikan terhadap Semangat Kerja, 2).Variabel Konflik Kerja mempunyai pengaruh yang positif dan signifikan terhadap Semangat Kerja, 3).Variabel Stres Kerja yang dimoderasi oleh kepemimpinan mempunyai pengaruh yang positif dan signifikan terhadap Semangat Kerja, 4).Variabel Konflik Kerja yang dimoderasi oleh Kepemimpinan mempunyai pengaruh yang positif dan signifikan terhadap Semangat Kerja.
KAJIAN PENGGUNAAN KARBON AKTIF DAN ZEOLIT SECARA TERINTEGRASI DALAM PEMBUATAN BIOMETHANE BERBASIS BIOGAS Harihastuti, Nani; ., Purwanto; ., Istadi
Jurnal Riset Industri Vol 8, No 1 (2014): Teknologi Proses Berbasis Efisiensi Energi
Publisher : Badan Penelitian dan Pengembangan Industri

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Abstract

Artikel ini merupakan suatu kajian dari hasil-hasil penelitian yang telah dilakukan untuk memurnikan biogas. Kandungn dalam biogas terdapat gas-gas pengotor seperti H2S, CO2, NH3, dan H2O yang apabila tidak dihilangkan dapat mempengaruhi pada proses pembakaran dan menimbulkan kerugian manusia dan lingkungan. Penelitian-penelitian yang telah dilakukan mengenai pemurnian biogas  hanya bertujuan untuk menghilangkan satu atau beberapa komponen gas pengotor secara parsial saja, maka dilakukan kajian ini agar dapat dilakukan penelitian pemurnian biogas secara terintegrasi untuk menghilangkan komponen gas pengotor secara menyeluruh sehingga diperoleh CH4 dengan kemurnian tinggi. Tahapan proses pemurnian  yang dirancangadalah proses kondensasi yang terintegrasi dengan proses adsorpsi menggunakan adsorben karbon aktif dan zeolit, sehingga dihasilkan gas CH4 dengan kemurnian tinggi sebagai biomethane sumber energi terbarukan. Kata kunci: integrasi, adsorpsi, karbon aktif-zeolit, biogas, biomethane 
JEJAK KARBON PENGOLAHAN SAMPAH DI tps tlogomas malang ., Sunarto; P. Hadi, Sudharto; ., Purwanto
Jurnal Media Teknik Sipil Vol 12, No 2 (2014): Agustus
Publisher : Jurnal Media Teknik Sipil

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Abstract

JEJAK KARBON PENGOLAHAN SAMPAH DI tps tlogomas malang Carbon Footprint of Solid Waste Processing At TPS Tlogomas MalangSunarto1, Sudharto P. Hadi2, Purwanto31,2,3Program Doktor Ilmu Lingkungan Universitas DiponegoroAlamat korespondensi : Jl. Imam Bardjo, SH No. 3 Semarang 50241Email: 1) narto@umm.ac.id, 2) sudhartophadi@yahoo.co.id.AbstractWaste sector is one of human activities that cause global warming. Decomposition of organic waste in landfill produces greenhouse gas emissions in the form of biogas consisting of methane and carbon dioxide. Solid waste processing in transfer station in the form of recycling and composting product potentially reduce carbon footprint, directly from the reduction in the volume of waste dumped in landfill and indirectly from the recovery of material. The purpose of this study was to determine the carbon footprint of waste processing at the transfer stations of Tlogomas Malang if developed several scenarios to enhance the capacity of processing. Life cycle approach is used to assess carbon footprint of waste management scenarios with the help of software SWM-GHG Calculator. The results showed that the processing of solid waste at current recycling rate of 40,57% – 80,41% (Status Quo) resulted in net carbon footprint of 1.147 ton CO2–eq /year. Increasing of processing capacity to 60 - 88% (Scenario 1) and 90 - 95% (Scenario 2) would reduce net carbon footprint to 801 ton  CO2–eq /year and427 ton CO2–eq/year respectively. If the processing of waste in transfer station of Tlogomas was discontinued (Scenario 3), net carbon footprint increased to 4,063 t CO2-eq/year.Keywords: carbon footprint, greenhouse gases, solid waste processing, life cycle analysis.AbstrakSektor persampahan merupakan salah satu kegiatan manusia yang menyebabkan pemanasan global. Proses dekomposisi sampah organik pada timbunan sampah menghasilkan emisi gas rumah kaca berupa biogas yang terdiri atas gas methana dan gas karbon dioksida. Pengolahan sampah di TPS untuk produk daur ulang dan kompos berpotensi mereduksi jejak karbon secara langsung dari penurunan volume sampah yang dibuang ke TPA dan secara tidak langsung dari pemulihan material sampah. Tujuan penelitian ini adalah untuk mengetahui jejak karbon pengolahan sampah di TPS Tlogomas di Kota Malang jika dikembangkan beberapa skenario pengolahan untuk meningkatkan kapasitas pengolahan sampah yang telah dilakukan selama ini. Pendekatan daur hidup digunakan untuk menaksir jejak karbon dari beberapa skenario pengolahan sampah di TPS dengan bantuan perangkat lunak SWM-GHG Calculator. Hasil analisis menunjukkan bahwa pengolahan sampah pada saat ini dengan tingkat daur ulang sampah sebesar 40,57% – 80,41% (Status Quo) menghasilkan jejak karbon bersih sebesar 1.147 ton CO2–eq/th. Peningkatan kapasitas pengolahan sebesar 60 – 88% (Skenario 1) dan 90 – 95% (Skenario 2) akan menurunkan jejak karbon bersih menjadi masing-masing sebesar 801 ton CO2–eq/th dan 427 t CO2–eq/th. Apabila pengolahan sampah di TPS Tlogomas dihentikan (Skenario 3), jejak karbon bersih yang dihasilkan meningkat menjadi 4.063 t CO2–eq/th.Kata kunci: jejak karbon, gas rumah kaca,  pengolahan sampah, analisis daur hidup.
Fenomena Underpricing Pada Perusahaan Go Public di Indonesia ., Purwanto; Agustiningsih, Sri Wahyu; Insani, Salman Faris; Wahyono, Budi
Jurnal Ekonomi Bisnis dan Kewirausahaan Vol 3, No 1 (2014): JBK Vol.3 No.1 Januari 2014
Publisher : Jurnal Ekonomi Bisnis dan Kewirausahaan

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Abstract

This research trytoanalyzethe factors that influence the occurrence of underpricing in companies that go public. This study uses a more variable varies the financial and non-financial variables contained in the prospectus which is composed of the reputation of the underwriter, auditor reputation, firm size, financial leverage, return on assets (ROA) and return on equity (ROE). According to the results of previous studies, these variables generally tend to show a significant effect on underpricing in companies that go public. This research is ekspost facto (causal comparative). Sample selection method used was purposive sampling and sample used was 132 sample companies doing an Initial Public Offering on the Indonesia Stock Exchange in the period 2002-2012. This study uses regression testing models. Regression analysis showed that only the underwriter reputation significantly influence underpricing
Jurnal Ekonomi Bisnis Dan Kewirausahaan Vol.III No.2 Januari 2014 Sulistyadi, Kohar; Sukamdani, Nugroho Budisatrio; ., Purwanto; Agustiningsih, Sri Wahyu; Isnaini, Salman Faris; Wahyono, Budi; Nurmansyah, Agung; Isnawati, Kus; ., Nurhayati; Cahyani, Rusnandari Retno
Jurnal Ekonomi Bisnis dan Kewirausahaan Vol 3, No 1 (2014): JBK Vol.3 No.1 Januari 2014
Publisher : Jurnal Ekonomi Bisnis dan Kewirausahaan

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Abstract

Jurnal ekonomi Bisnis dan kewirausahaan ini  Vol  III No 1 ini menghadirkan 6 artikel dari berbagai  Sub disiplin Administrasi bisnis. Artikel pertama berkaitan dengan  dunia kewirausahaan dengan judul  analisis faktor  dominan yang bergaruh terhadap  keberhasilan berwirausaha pada sarjana Universitas Sahid Surakarta, artikel ini merupakan hasil penelitian  dengan metode kuantitatif yang dilakukan oleh Kohar Sulistyadi, Nugroho B Sukamdani. Penelitian tersebut memperjelas bahwa minat sarjana USS dalam berwirausaha masih rendah. beberapa indikasi menunjukkan bahwa karakter wirausaha dari para sarjana maupun mahasiswa USS belum sepenuhnya memahami atas jiwa kewirausahaan yang dicanangkan sebagai Visi dan Misi USS, sehingga perlu usaha keras untuk membangun persepsi dan memperkuat program bisnis center atau inkubator bisnis di lingkungan USS. Artikel kedua berkaitan dengan fenomena underpricing pada perusahaan yang go public di Indonesia, oleh peneliti Purwanto, Sri Wahyu Agustiningsih, Salman Faris Insani dan Budi Wahyono.  Dimana IPO (Initial Public Offering) merupakan salah satu alternatif pembiayaan yang dapat digunakan oleh perusahaan yang telah go public yaitu dengan melakukan penerbitan saham baru untuk dijual di pasar perdana sebelum diperdagangkan di pasar sekunder (bursa efek). Artikel Ketiga adalah Potensi Pariwisata Dalam Perekonomian Indonesiaoleh Agung Nurmansyah. Sedangkan artikel keempat adalah Profitabilitas Perbankan Syariah, Kun Ismawati dan Nurhayati.  Artikel tersebut menganalisis pengaruh Size, Total Equity to Total Assets, Total Loans to Total Assets, dan Total Deposits to Total Assets terhadap ROA (Return on Assets) pada Perbankan Syariah MI dan SM di Indonesia. Artikel terakhir yaitu Pendekatan Supply Chain Management Untuk Meningkatkan Daya Saing Pada Bisnis Bunga Segar oleh Rusnandari Retno Cahyani.
Pengaruh Struktur Corporate Governance Terhadap Initial Public Offering (Ipo)Underpricing Di Indonesia ., Purwanto; Agustiningsih, Sri Wahyu; Insani, Salman Faris; Wahyono, Budi
Jurnal Ekonomi Bisnis dan Kewirausahaan Vol 4, No 1 (2015): JBK Vol.4 No.1 Januari 2015
Publisher : Jurnal Ekonomi Bisnis dan Kewirausahaan

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This research try to examine whether corporate governance when the company madean Initial Public Offering (IPO) affect the level of underpricing shares of companies that go public by using the period 2002-2012. This study focuses on the influence of corporate governance structure on the level of underpricing by using control variables underwriter reputation, return on assets (ROA), firm size, financial leverage, and return on equity (ROE). According to the results of previous studies, these variables generally tend to show a significant effect on underpricing in companies that go public.            This research is ekspost facto (causal comparative). Sample selection method used was purposive sampling and sample used was 131 sample companies doing an Initial Public Offering on the Indonesia Stock Exchange in the period 2002-2012. This study uses regression testing models. Regression analysis showed that only the underwriter reputation significantly influence underpricin.
Potensi Rebusan Kulit Buah Manggis Alami (Garcinia mangostana Linn) untuk Meningkatkan Aktivitas Mikrobisida Sel Neutrofil terhadap Streptococcus mutans (The Potency of Mangosteen Peel Infution (Garcinia mangostana L.) to Increase Neutrophil Microbicidal Sakinah, Athiyah Naila; Amin, Muhammad Nurul; ., Purwanto
Pustaka Kesehatan Vol 3, No 1 (2015)
Publisher : Pustaka Kesehatan

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Abstract

Neutrophils were part of leucocyte cells which dominate in blood circulation. When the microorganism entered the body, neutrophils kill it immediately. The steps that were migration, ingestion, swallowing, and microbicidal activity or intercellular killing. The contents of mangosteen peel is presumed to help neutrophils beat bacteria. Samples numbered 28 consist of 7 treatment groups, namely K 1 (negative control), K II (positive control), K III 100% MPI (Mangosteen Peel Infution), K IV 75% MPI, K V 50% MPI, K VI 25% MPI, and K VII 100% MPIwithout neutrophils. Isolated neutrophils exposed to MPI appropriate treatments groups above and then incubated for 3 hours. Subsequently exposed to S. mutans and incubated again for 3 hours. After that, the sample werecultured in BHI-A media and incubated for 1x24 hours. Furthermore, bacterial colonies were counted with a colony counter method. The result showed a significant difference between MPI treatment groups with control groups. The conclusion of this research is thenatural mangosteen peel infution hasthe potential to increase microbicidal activity of neutrophils and can act as an antibacterial.   Keywords: mangosteen (Garcinia mangostana L.),microbicidal,neutrophils, S. mutans.
Dampak Konversi Tata Guna Lahan di Daerah Resapan Terhadap Penurunan Cadangan Airtanah di Kabupaten Sleman, Daerah Istimewa Yogyakarta (Effect of Landuse Conversion at Catchment Area to Decrease Groundwater Reserves, In Sleman Regency, Yogyakarta) ., Sutanto; ., Purwanto; Haty, Intan Paramita
PROMINE Vol 3, No 1 (2015): PROMINE
Publisher : Jurusan Teknik Pertambangan FT UBB

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Utilization of land use in the Daerah Istimewa Yogyakarta Province resulted in an increase in subsidence and reduced groundwater recharge area of rainwater in catchment areas. The aim of this study was to determine the area of agricultural land were converted to housing, other infrastructure, and the mining area during the last 5 years, as well as to analyze changes in the hydrological system due to land conversion, especially the water supply to the area of the aquifer.     This study is a summary based on secondary data collection, observation and description in the field, measurements of rock permeability and infiltration, as well as laboratory and studio work. Employment in the field is also observed for conversion of land use that occurred and compare the physical properties of rocks before and after conversion. Evaluation is emphasized on the water balance equilibrium calculation has been calculated on the amount of percentage changes in land use and analysis of the impact of the conversion of land use in the catchment area to change the content of groundwater.     Based on the results of the calculation of the projected reserves of groundwater due to land conversion, water reserves and infiltrasiakan volume continued to decline from year to year. This study is expected by the general public is expected to use the existing land well and wisely with regard to groundwater reserves so that it can minimize the reduction in water reserves and infiltration from year to year.Keywords: landuse, groundwater level, catchment area, infiltration, aquifer