Judul: Penentuan Kondisi Optimum pada Proses Fenton dalam Pengolahan Limbah Tekstil
Abstrak: Textile waste from the textile industry activity increases with the textile industry activities. Textile waste has relatively high biochemical oxygen demand (BOD), color, total suspended solids (TSS), electrical conductivity, and zinc content. Therefore, waste treatment is needed. One of the waste treatments is Fenton process using Fenton reagent that is hydrogen peroxide (H2O2) and ferrous sulfate (FeSO4). Fenton reagent can oxidize and degrade organic compounds. In this study, textile waste was tested based on the influence of pH, concentration of hydrogen peroxide, and the concentration of ferrous sulfate. The largest decrease occurred in the BOD under pH 5 in combination with H2O2 concentration of 25 mg/L and the concentration of FeSO4 50 mg/L. Beside that, this combination showed significant reduction of the three other parameters, namely TSS, electrical conductivity, and zinc content.
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Judul: Pengolahan limbah cair yang mengandung logam merkuri dengan reaksi Fenton dan presipitasi sulfida
Abstrak: Discharging wastewater to water body can cause environment contamination if its quality does not meet with the corresponding quality standard. For analysis, every laboratory use various hazardous chemicals according to reference methods. This research was intended to reduce environmental contamination by reducing organic matters and metal that exists in wastewater before discharging it to the waters. Wastewater samples were oxidized using Fenton reaction with ratios of 1:10, 1:25, 1:50, and 1:100 (b/b) to reduce its organic matters level and continued by sulfide precipitation using Na2S 13% (b/v) with volumes of 7, 9, 10, 11, 15, and 20 mL in 100 mL samples to reduce its metal content level. The content of organic matters was measured by chemical oxygen demand analysis and for its metal level contents was analyzed using atomic absorption spectroscopy. The highest percentage removal of organic matter level was 92.01% from the ratio of 1:100 and for inorganic compounds reached 99.99% in various Na2S volume. The results indicated that this method could reduce organic matters and metal content level.
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Judul: Karakteristik Suara Song Burung Kenari (Serinus canaria) Postur Besar dan Kecil.
Abstrak: Burung kenari (Serinus canaria) memiliki nyanyian yang sangat bervariasi dengan durasi yang panjang dan merupakan tipe burung bernyanyi open learners. Penelitian ini bertujuan menganalisis karakteristik suara song burung kenari (Serinus canaria). Penelitian dilakukan pada bulan April sampai Juni 2017 di Bogor, Jawa Barat. Perekaman suara song terhadap 12 ekor burung kenari jantan dilakukan dengan menggunakan mikrofon Sennheiser ME66 dan alat perekam Sony PCM-D50. Burung kenari yang digunakan merupakan burung yang pernah mengikuti kontes burung kicau dan memiliki predikat juara kontes burung. Amplitudo, durasi suara, frekuensi, dan volume suara burung dianalisis dengan menggunakan software Raven Pro 1.4. Data tersebut selanjutnya dianalisis deskriptif. Hasil analisis suara menunjukkan bahwa burung kenari memiliki banyak syllable, suara song rapat dan tidak terputus-putus, tempo yang cepat, dan adanya pengulangan suku kata pada setiap suara song. Burung kenari postur kecil memiliki rataan durasi lebih panjang dibandingkan dengan kenari postur besar, tetapi burung kenari besar memiliki rataan max amplitudo, average power, max power, min amplitudo, peak amplitudo, dan peak frekuensi.
Keyword: karakteristik suara (song), kenari, syllable