Articles

PENGARUH UMPAN TERHADAP KEEFEKTIFAN PITFALL TRAP UNTUK MENDUKUNG PRAKTIKUM EKOLOGI HEWAN DI LABORATORIUM EKOLOGI FMIPA UNSYIAH Jaya, Adi Surya; Widayat, Widayat
Jurnal Bioleuser Vol 2, No 3 (2018): Desember 2018
Publisher : Department of Biology, Faculty of Mathematics and Natural Sciences, University of Syiah Ku

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1175.576 KB) | DOI: 10.24815/jobioleuser.v2i3.14963

Abstract

Penelitian ini bertujuan untuk melihat keefektifan penggunaan umpan pada Pitfall trap, sebagai refererensi praktikum ekologi hewan dan ekologi serangga. penelitian ini dilaksanakan dari bulai Mei sampai bulan Agustus 2018 di kebun percobaan Biologi, FMIPA Universitas Syiah Kuala. Identifikasi sampel dilakukan di Laboratorium Ekologi Jurusan Biologi FMIPA, Universitas Syiah Kuala. Metode pengambilan sampel serangga dilakukan dengan metode Pitfall Trap menggunakan umpan berupa feses ayam, sapi serta manusia. Pengambilan sampel dilakukan pada tiga titik dengan masing-masing ulangan sebanyak 10 kali. Data dianalisis dengan menggunakan ANOVA dengan uji lanjut Tuckey. Hasil penelitian menunjukkan bahwa penggunaan umpan feses manusia terdapat pengaruh yang berbeda nyata dengan umpan feses sapi, ayam maupun kontrol. Namun pemberian umpan feses sapi dan ayam tidak menunjukkan perbedaan yang nyata. Jumlah spesies yang ditemukan lebih dominan dari famili Scarabaeidae yang berjumlah 7 spesies. Sedangkan yang lainnya seperti Carabidae, Lycosidae, Acridoidae, Formicidae, Carcinophoridae, Muscidae, Culicidae, Grylidae, Trachelidae, Entomobryadae, Scolopendridae, Anisolabidae, Aphidoidae, Juluidae, Staphylinidae, Pentatomidae, Locustidae hanya terdapat 1 spesies saja. Selain itu, faktor lainnya yang mendukung yaitu faktor lingkungan seperti suhu, kelembaban dan pH tanah. Rata-rata suhu lingkungan harian yaitu 27-31oC dan kelembaban relatif udara 55-85 %.
ULTRASOUND ASSISTED ESTERIFICATION OF RUBBER SEED OIL FOR BIODIESEL PRODUCTION Widayat, Widayat; Fajar Tamtomo Kiono, Berkah
International Journal of Renewable Energy Development Vol 1, No 1 (2012): February 2012
Publisher : Center of Biomass & Renewable Energy, Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (750.91 KB) | DOI: 10.14710/ijred.1.1.1-5

Abstract

Production of biodiesel is currently shifting from the first to the second generation inwhich the raw materials are mostly from non-edible type oils and fats. Biodiesel production iscommonly conducted under batch operation using mechanical agitation to accelerate masstransfers. The main drawback of oil esterification is the high content of free fatty acids (FFA) whichmay reduce the yield of biodiesel and prolong the production time (2-5 hours). Ultrasonificationhas been used in many applications such as component extraction due to its ability to producecavitation under certain frequency. This research is aimed to facilitate ultrasound system forimproving biodiesel production process particularly rubber seed oil. An ultrasound unit was usedunder constant temperature (40oC) and frequency of 40 Hz. The result showed that ultrasound canreduces the processing time and increases the biodiesel yield significantly. A model to describecorrelation of yield and its independent variables is yield (Y) = 43,4894 ? 0,6926 X1 + 1,1807 X2 ?7,1042 X3 + 2,6451 X1X2 ? 1,6557 X1X3 + 5,7586 X2X3 - 10,5145 X1X2X3, where X1 is mesh sizes, X2ratio oil: methanol and X3 type of catalyst.
ENTREPRENEURIAL ATTITUDE AND STUDENTS BUSINESS START-UP INTENTION: A PARTIAL LEAST SQUARE MODELING Widayat, Widayat; Ni matuzahroh, Ni matuzahroh
Jurnal Manajemen dan Kewirausahaan Vol 19, No 1 (2017): MARCH 2017
Publisher : Institute of Research and Community Outreach - Petra Christian University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (379.261 KB) | DOI: 10.9744/jmk.19.1.46-53

Abstract

This article is designed to examine the role of the entrepreneurial spirit, education and in build­ing­ an attitude about working as an entrepreneur, and his influence on the intention to start a business, to the students. Data were collected using a questionnaire has been prepared and maintained the validity and relia­bility. Questionnaires given to the respondent students were selected as samples at several universi­ti­es in Malang, East Java, Indonesia. The collected data were analyzed by using Partial Least Square. The a­­na­­ly­sis showed entrepreneurial spirit and education contribute to the formation of entrepreneurial atti­tu­des. Attitudes are formed encourage entrepreneurship intentions to start a business significantly.
Analisis Kadar Etanol dalam Obat Batuk dengan Metode Kromatografi Cair Nuur Annisa, Arianti; Nuryadi, Handung; Widayat, Widayat; Ayu Sofiati, Dita
Indonesia Journal of Halal Vol. 2 (1) 2019
Publisher : Pusat Kajian Halal Undip

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (441.377 KB) | DOI: 10.14710/halal.v2i1.5277

Abstract

Etanol merupakan senyawa kimia yang umum digunakan sebagai pelarut dalam obat-obatan. Keberadaan etanol dalam obat dapat diragukan kehalalannya. Diperlukan analisa kandungan etanol dalam suatu produk. Kromatografi cair merupakan metode yang akurat untuk mengetahui keberadaan etanol dalam sampel. Penelitian ini bertujuan untuk menganalisa kandungan etanol dalam obat batuk menggunakan metode HPLC. Metode yang dilakukan terdiri dari persiapan standar etanol dan sampel obat batuk, serta analisa sampel dengan HPLC. Data hasil analisa diolah dengan menggunakan software Lab Solutions. Selanjutnya disusun kurva analitik dan persamaan linear. Hasil analisa menunjukkan sampel obat batuk jenis XXX memiliki kandungan senyawa etanol. Dari hasil yang diperoleh dapat disimpulkan bahwa metode HPLC tepat digunakan untuk menentukan kehalalan suatu produk.
PEMBUATAN BIODIESEL DARI MINYAK GORENG BEKAS DENGAN PROSES CATALYTIC CRACKING Buchori, Luqman; Widayat, Widayat
TEKNIK Volume 28, Nomor 2, Tahun 2007
Publisher : Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (395.817 KB) | DOI: 10.14710/teknik.v28i2.2116

Abstract

Crude oil is a source of energy which is not be renewable. This fact motivates so much countries ineconomizing on fuel. Many researches have been done to gets another fuel substitute the crude oil.Biodiesel is represented as fuel instead of diesel fuel, and it is produced from vegetable oil. In the otherside, ex-cooking oil is waste-product from food industry, restaurant and household which is potential tobe alternative fuels because of the high contents of carbon and hydrogen atoms. Commonly the biodieselmade from vegetable oil by esterification and transesterification process. But if using esterification andtransesterification process to ex-cooking oil material, it is not economically feasible because the processmakes another reaction between alkaly catalist and oil to produce soap. One of biodiesel process iscatalytic cracking of the ex-cooking oil. This research is aimed to analyze zeolite catalist size effect(0.125mm; 0.3375mm; 0.425mm; 0.85mm; 1.18mm), and acid concentration on the product (2N; 3N;4N). This result shows that at 4N acid concentration and 0.125 mm zeolite catalist size is optimal whichcan reach diesel specification.
POTENCY OF MICROALGAE AS BIODIESEL SOURCE IN INDONESIA Hadiyanto, Hadiyanto; Widayat, Widayat; Cahyo Kumoro, Andri
International Journal of Renewable Energy Development Vol 1, No 1 (2012): February 2012
Publisher : Center of Biomass & Renewable Energy, Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (931.85 KB) | DOI: 10.14710/ijred.1.1.23-27

Abstract

Within 20 years, Indonesia should find another energy alternative to substitutecurrent fossil oil. Current use of renewable energy is only 5% and need to be improved up to 17%of our energy mix program. Even though, most of the area in Indonesia is covered by sea, howeverthe utilization of microalgae as biofuel production is still limited. The biodiesel from currentsources (Jatropha, palm oil, and sorghum) is still not able to cover all the needs if the fossil oilcannot be explored anymore. In this paper, the potency of microalgae in Indonesia was analysed asthe new potential of energy (biodiesel) sources.
EFEK AERASI TERHADAP PERUBAHAN RESIDU H2O2 AIR FERMENTASI MOCAF (MODIFIED CASSAVA FLOUR) Yaqin, Nurul; Al-Baarri, Ahmad Ni'matullah; Budihardjo, Mochamad Arief; Widayat, Widayat
Jurnal Aplikasi Teknologi Pangan Vol 9, No 1 (2020): February 2020
Publisher : Faculty of Animal and Agricultural Sciences, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17728/jatp.6181

Abstract

Penelitian ini bertujuan untuk mengetahui perubahan kadar H2O2 yang berpotensi menjadi pencemar lingkungan beserta parameter kualitas air fermentasi mocaf (AFM) lainnya setelah diberikan perlakuan aerasi. Limbah mocaf  yang diberikan perlakuan aerasi mengalami penurunan kadar H2O2 lebih besar dari non aerasi. Berdasarkan uji beda T-test antara perlakuan aerasi dengan non aerasi kadar H2O2 memiliki perbedaan yang signifikan (sig. p= 0,018, p<0,05).  AFM non aerasi mengalami penurunan L* sebesar 5,9%, sedangkan perlakuan aerasi menurun lebih besar dengan persentase penurunan sebesar 15,8%. TDS AFM tidak mengalami perbedaan yang signifikan antara perlakuan aerasi dengan non aerasi (P= 0,226 ,p>0,05) demikian juga dengan pameter turbiditas (P= 0,117, P>0,05) dan OD 610 nm (P= 0,987, P> 0,05). 
OPTIMASI PEMBUATAN DIETIL ETER DENGAN PROSES REAKTIF DISTILASI Widayat, Widayat; Satriadi, Hantoro
Reaktor Volume 12, Nomor 1, Juni 2008
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (242.567 KB) | DOI: 10.14710/reaktor.12.1.7-11

Abstract

DiEtil Eter banyak digunakan sebagai bahan pelarut untuk reaksi organik dan pemisahan senyawa organik dari sumber alamnya, sebagai bahan bakar. DiEtil Eter umumnya diproduksi dengan proses dehidrasi etanol dengan katalis asam sulfat pada suhu 125­­­0C ? 1400C (proses barbet). Penelitian ini bertujuan untuk memperoleh kondisi optimum pada pembuatan dietil eter dengan katalis asam sulfat dan proses reaktif distilasi. Variabel yang dioptimasi adalah konsentrasi asam sulfat awal dan perbandingan mol reaktan etanol dengan asam sulfat. Proses optimasi menggunakan metode respon permukaan dan pengolahan data dengan perangkat lunak Statistica(R.) Proses pembuatan dietil eter dilakukan pada volume 700 ml, waktu 100 menit dan suhu operasi 125-1300 C. Hasil penelitian menunjukkan bahwa model matematika yang diperoleh hubungan konversi etanol dengan perbandingan mol reaktan etanol dengan asam sulfat dan konsentrasi awal asam sulfat  adalah . Konversi etanol optimum sebesar 31,83 % pada kondisi operasi perbandingan mol reaktan etanol dengan asam sulfat 1 : 1,30 dan konsentrasi awal asam sulfat 10,98 M.
OPTIMIZATION OF INITIAL PH AND TOTAL SUGAR CONCENTRATION VARIABLES ON CITRIC ACID PRODUCTION FROM PINEAPPLE WASTE WITH ASPERGILLUS NIGER YEAST BY USING RESPONSE SURFACE METHODOLOGY Widayat, Widayat; Abdullah, Abdullah; Satriadi, H.; Hadi, M.
Jurnal Rekayasa Kimia & Lingkungan Vol 8, No 1 (2011): Jurnal Rekayasa Kimia & Lingkungan
Publisher : Chemical Engineering Department, Syiah Kuala University, Banda Aceh, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (248.767 KB)

Abstract

Citric acid can be produced from pineapple waste by using fermentation process. This process is done in bubble column reactor with Aspergillus niger yeast. The objective of this research is to find the optimum conditions of initial pH and total sugar concentration. The optimization method used was response surface methodology. This research was carried out at a temperature of 30 oC, spore concentration of 1.23 x 109 spore/ml, total volume 2.0 liter, flow rate of air 58.07 cc/sec and a 5% antifoam concentration. The fermentation process lasted 7 days and the citric acid concentration was analyzed by High Pressure Liquid Cromatography (HPLC) method. Statistica 6 software was used for the data treatment. The mathematical model for the optimization citric acid fermentation in bubble column reactor is Y = 54.507 + 2.9851X - 8.987X12 - 2.581X2 - 15.446X22 - 7.989X1X2 The parameter of Y is citric acid yield, X1 is a coding initial pH and X2 is a coding total sugar concentration. The results has given an initial pH optimum 3.61 and total sugar concentration 19,285% w/v with optimum an yield of 55.03 % .Keywords: Bubble column bioreactor, Citric acid fermentation, Initial pH, Total sugar concentration, Response surface methodology
STUDI PENGARUH METODE PEMBUATAN DAN SUMBER BAHAN BAKU PADA PROSES PRODUKSI KATALIS DARI ZEOLIT ALAM Widayat, Widayat; Satriadi, H; Roesyadi, Achmad; Rachimoellah, H M
METANA Vol 9, No 01 (2013): Juli 2013
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (201.561 KB) | DOI: 10.14710/metana.v9i01.7206

Abstract

Abstract Indonesia has the potential for considerable natural zeolites. This natural zeolites, silica deposits typically have amounted to 60%, it also contains components of alumina. Silica and alumina oxide compound that can be used as a catalyst, particularly in the process of dehydration. This research aims to study the influence of the method of manufacture of catalysts in the production process of natural zeolite catalyst. The observed response is the surface area in comparison with silica, alumina and kristalitas. The surface area is measured by the method kristalitas and BET with XRD analysis as well as the composition of the silica-alumina with AAS. The methods used in this research is the process of exchanging ions-development with alcohol and dealuminiation process with hydrochloric acid solution. The raw materials used are natural zeolite from Malang, Lampung Province and Regency of Gunung Kidul. The results showed that dealuminasi process with hydrochloric acid produces a better surface area compared to the ion exchange process and development with alcohol. Besides the resulting catalyst with silicate dealuminasi process is a catalyst if the raw material of the Regency of Gunung Kidul and mordenite type if the raw materials used originate from Malang. Key words : Zeolite catalyst, natural zeolites, surface area, crystallite,Si/Al comparison
Co-Authors A. Sadikky DP A. Wildan Abdullah Abdullah Abdullah, Fas Nurussalami Achmad Roesyadi Achmad Wildan Aini, Apsari Puspita Aji Prasetyaningrum Al-Baarri, Ahmad Ni'matullah Andri Cahyo Kumoro Ariadi, Ariadi Ariadi, Ariadi Arief Budiman Arif Budianto, Irawan Arwan, Berriandi Arwan, Berriandi Ayu Sofiati, Dita Baeti Pridiana, Dita Bakti Jos Berkah Fajar Tamtomo Kiono Budianto, Irawan Arief Budiyono Budiyono D. Ingrid A D. soetrisnanto Danny Soetrisnanto Devina Ingrid A. Dewanto Dewanto Driastuti, Faradilla Enda Merizki br Ginting, Enda Merizki H Hadiyanto H M Rachimoellah H Satriadi H. Anggraeni H. Satriadi Hadiyanto Hadiyanto Hanapi bin Mat Handung Nuryadi Hantoro Satriadi Haris Nu’man Aulia I. Hartati Indah Hartati Indah Riwayati Irawan Irawan Ismangoen Ismangoen, Ismangoen Jaya, Adi Surya Jaya, Adi Surya Johnner P Sitompul Kurdianto Kurdianto, Kurdianto Kurnia, Atik Kusmiyati Kusmiyati Laira, Inga Luqman Buchori M. Hadi Masyhad Masyhad Mega, Ayu Meiny Suzery Mochamad Arief Budihardjo Muhammad Rachimoellah Ni matuzahroh, Ni matuzahroh Ni matuzahroh, Ni matuzahroh Ni?matullah Al-Baarri, Ahmad Nur Fatana, Mardelia Nurul Yaqin Nuur Annisa, Arianti Raharjo, Sonya Hakim Rahmi Putri, Sylvia Ratnawati Ratnawati S Suherman Senjaya, Fredy Arief Setia Budi Sasongko Setyawaty, Rety Sitompul, J. P. Soerawidjaja, T. H. Sri Puji Lestari Striadi, H. Sulistyanto, Dwi Suroso Agus Saputro, Suroso Syaiful Syaiful Tatang H. Soerawidjaja Teluk Sebodo, Teluk Tutuk Djoko Kusworo Utama, Bobby Indra Utama, Bobby Indra Utomo, Dani Puji Widiarto Widiarto, Widiarto Winaningsih, Ima Winarni Agustini, Tri Yudhy Dharmawan Yuliyandjaja, John Philia