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KINERJA ROTOR SAVONIUS DENGAN MEKANISME PENGARAH DAN PENGUMPUL ALIRAN ANGIN (MPPA) Widyanto, Susilo Adi; Ismoyo, Ismoyo; Cahjono, Surdjanto; Nugroho, Dwi
ROTASI VOLUME 16, NOMOR 3, JULI 2014
Publisher : ROTASI

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Abstract

Cadangan  energi fosil dunia terus menurun, pada sisi lain kebutuhan terus meningkat dari waktu ke waktu. Disamping itu dampak pemakaian energi  fosil semakin dirasakan dengan turunnya kualitas lingkungan akibat pencemaran yang berdampak pada perubahan iklim yang semakin ekstrim. Untuk itu pemanfaatan energi yang dapat diperbaharui kian mendesak dilakukan seperti halnya energi angin. Mengacu pada kondisi geografis Indonesia, pengembangan turbin angin berkecepatan rendah  berpotensi besar untuk dapat diaplikasikan sebagai pembangkit energi listrik. Paper ini membahas kinerja rotor Savonius yang dikombinasikan dengan MPPA. Dari hasil pengujian diperoleh bahwa penggunaan MPPA efektif digunakan untuk menurunkan torsi awal (start up) rotor sehingga cocok digunakan untuk daerah dengan potensi energi angin yang rendah. Namun dari sisi yang lain MPPA memperpanjang waktu respon rotor sehingga kurang sesuai untuk lokasi dengan kondisi arah aliran angin yang berubah-ubah.
Performance of Some Arabica Coffee Local Varieties from Gayo Highland Hulupi, Retno; Nugroho, Dwi; ., Yusianto
Pelita Perkebunan (Coffee and Cocoa Research Journal) Vol 29, No 2 (2013)
Publisher : Indonesian Coffee and Cocoa Research Institute

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Abstract

Recently, most of coffee farmers at Gayo highland (Aceh) are planting various of local varieties, namely Timtim Aceh, Borbor, P 88, BP 542A and Ateng Super. Those varieties have been planted to replace S line and Catimor Jaluk varieties which were damaged by leaf rust and root disease. Research on the performance of those varieties was to investigate superior characteristics of each variety and moreover as based to choose the best one as released variety for Gayo Highland. Research finding revealed that Timtim Aceh and Borbor varieties were well adapted to Gayo highland conditions with yielding ability 0.956 ton/ha and 0.909 ton/ha, respectively. Although the highest yield was obtained by Ateng Super variety (1.76 ton/ha green coffee), but not stable, therefore it could not be categorized as superior variety. The previous two varieties also had good cup quality (by standard assesment of Specialty Coffee Association of America), then it could contribute Gayo coffee specialty product. The resistance test for leaf rust disease in the field plantation, showed all varieties demonstrated varying in their resistance. BP 542A variety was the most resistant type, whereas Timtim Aceh and Borbor varieties were moderately. However all varieties become more susceptible if planted at lower altitude, less than 1,000 m asl. The resistance test to coffee berry borer and parasitic nematode showed that Timtim Aceh and Borbor varieties were ranked into almost resistant to resistant. Based on all result of the superior characteristics testing, Timtim Aceh and Borbor varieties were the best one, and it could be proposed to be released as Arabica coffee varieties that suitable at Gayo highland. Key words: Arabica coffee, Gayo highland, local varieties, variety performance, cup quality, yielding, resistant to leaf rust disease
Physical and Flavor Profiles of Arabica Coffee as Affected by Cherry Storage Before Pulping ., Yusianto; Nugroho, Dwi
Pelita Perkebunan (Coffee and Cocoa Research Journal) Vol 30, No 2 (2014)
Publisher : Indonesian Coffee and Cocoa Research Institute

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Abstract

Harvesting and pulping process of coffee cherry in the same day is inaccesible. Storage of coffee cherry before pulping was carried out incorrectly. Some storage treatments before pulping of Arabica coffee cherry had been examined at Indonesian Coffee and Cocoa Research Institute using Arabica coffee cherries from Andungsari Experimental Garden, Bondowoso, East Java. Treatments of the experiment were method and period of cherry storage. Methods of coffee cherry storage were put in plastic sacks; immerse in water, without water replacement; and immerse in water with daily water replacement. Period of coffee cherry storage were 0, 1, 2, 3, 4, 5, 6, and 7 days. After storage treatments, the coffee cherries were pulped, fermented, washed, sundried, and dehulled. The experiment were carried out using randomized block design with three replications. Observation of coffee cherry during storage periods was done on the physical and temperature. Observation of the green coffee were done on the color dan bulk density. The green coffee were roasted at medium roast level for sensory analysis. Observation of roasting profile were out-turn, bulk density and pH of roasted coffee. Sensory analysis used Specialty Coffee Association of America method. Methods and period of cherry storage before pulping significanly influence on the cherry color, parchment color, green coffee color, and the flavor profile of Arabica coffee. Color of dry parchment changed to be red-brown becouse of cherry immersed in water for two days or more. In plastic sacks, Arabica coffee cherry may be stored only for two days, but underwater with or without water replacement, should be not more than five days. Green and sensory quality of Arabica coffee will be deteriorated after five days storage underwater. Coffee cherry storage immerse in water with daily replacing water may improve sensory quality of Arabica coffee.Key word: Arabica coffe, storage, pulping, flavor, physical perqutions 
SINTESIS MEMBRAN KITOSAN-PVA TERIKAT SILANG UNTUK MENURUNKAN KADAR ZAT WARNA REMAZOL RED Nugroho, Dwi; Susatyo, Eko Budi; Prasetya, Agung Tri
Indonesian Journal of Chemical Science Vol 3 No 1 (2014)
Publisher : Indonesian Journal of Chemical Science

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Abstract

Tujuan dari penelitian ini adalah untuk mengetahui perbedaan karakteristik membran kitosan-PVA tanpa asam sulfat dengan membran kitosan-PVA terikat silang asam sulfat, serta mengetahui efektivitas dan membran kitosan-PVA terikat silang asam sulfat dalam proses menurunkan kadar zat warna Remazol Red. Uji karakteristik membran dapat dilihat dari gugus fungsi membran menggunakan FT-IR (Fourier Transform Infra Red), sifat porositas menggunakan BET (Brunnaeur Emmet Teller), struktur Kristal menggunakan XRD (X-Ray Diffraction) serta pengukuran permselektivitas dan koefisien permeabilitasnya. Karakterisasi FT-IR menunjukkan gugus fungsi yang terdapat pada membran antara lain –OH, -CH2, -CO-, -CH3-, -NH2 dan SO42-. Pengukuran koefisien rejeksi yang menunjukkan selektivitas membran dilakukan pada proses penurunan kadar zat warna Remazol Red. Komposisi terbaik diperoleh pada membran kitosan-PVA terikat silang asam sulfat 0,5 M dengan koefisien rejeksi sebesar 79,84 % terhadap larutan Remazol Red pH 4 dan 66,04 % terhadap larutan Remazol Red pH 7.
KUALITAS PELAYANAN E-AUCTION PADA KANTOR PELAYANAN KEKAYAAN NEGARA DAN LELANG SURAKARTA Nugroho, Dwi
JI@P Vol 5, No 1 (2018): JI@P
Publisher : JI@P

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Abstract

Wealth Of State And An Auction Of Surakarta”. Slamet Riyadi University.Thesis, unpublished.The purpose of this study is: to know the procedure of service andcommunity satisfaction in E-Auction at the Service Office a wealth of Stateand an auction of Surakarta? Research conducted at the Service Office awealth of State and an auction. Research conducted using qualitativeapproach. Data collection techniques used are in-depth interviews,documentation, and observation/observation. Data analysis techniquesusing interactive analysis models. Results of the study shows that theprocedures E-auction services On Service Office a wealth of State andSurakarta Auction consists of 11 stages, all stages conducted meleluiinternet media, the level of satisfaction of the public against the E-Auction,belongs to the satisfied, because the expectations of society.Keywords: quality of service and E-Auction.
UJI EFEK ANTIMIKROBA DALAM PRODUK MADU YANG BEREDAR DI PASAR MINGGU JAKARTA SELATAN Kristanty, Ruth Elenora; Suriawati, Junie; Nugroho, Dwi
SANITAS : JURNAL TEKNOLOGI DAN SENI KESEHATAN Vol 8 No 2 (2017)
Publisher : Politeknik Kesehatan Kemenkes Jakarta II

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Abstract

Madu merupakan produk pangan yang bernutrisi tinggi dan dikomsumsi oleh hampir seluruh populasi penduduk di dunia, serta mempunyai fungsi sebagai antimikroba.  Staphylococcus aureus (S. aureus) adalah bakteri Gram positif yang sering ada dalam bahan pangan dan Escherichia coli (E. coli) adalah bakteri Gram negatif  yang sering muncul dalam masalah sanitasi lingkungan yang keduanya dapat menyebabkan penyakit infeksi. Penanganan penyakit infeksi tersebut dapat diatasi dengan antimikroba seperti madu. Tujuan penelitian ini adalah melakukan uji efek antimikroba terhadap produk madu yang beredar di wilayah Pasar Minggu. Uji efek antimikroba dilakukan secara in vitro menggunakan metode difusi agar dengan mengukur zona bening yang terbentuk dimana bakteri terhambat pertumbuhannya dengan adanya madu. Konsentrasi madu yang digunakan 25%, 50%, 75%, dan 100% (tidak diencerkan) dan sebagai kontrol aquades. Hasil penelitian menunjukkan bahwa madu yang diuji dengan berbagai konsentrasi pengenceran menghasilkan zona hambat dan semakin tinggi konsentrasi semakin besar zona hambat yang dibentuk, yang menunjukkan aktivitas antimikroba terhadap bakteri S. aureus dan E. coli.