Judul: Pengolahan limbah cair praktikum analisis kualitatif logam berat menggunakan polialuminium klorida sebagai koagulan
Abstrak: Research activity in laboratory often use substances containing heavy metals. One of them is qualitative analysis for chloride and spot test for measuring the existence of heavy metals on the samples. This wastewater contains various chemicals especially heavy metals and acidic substances. It appears with low pH value and high concentration of dye and heavy metals. Waste storage containers also need handling. Based on observation, polypropylene bottle became dark-colored after it kept heavy metal waste for 2 years. In this research, wastewater samples were treated with coagulation process to obtain optimum condition for polyaluminum chloride (PAC) and to identify polypropylene bottle using scanning electron microscope and energy dispersive spectrometer. Samples were coagulated using PAC at concentrations 500, 600, 700, 800 mg/L, and pH 7, 8, 9, 10. Parameters observed were pH, color, and Cr, Ni, and Pb heavy metal content. The result showed that the highest Cr reduction was 97.99% at coagulation pH 10 and PAC concentration of 700 mg/L. Polypropylene bottle showed carbon content lowering in all 3 sampled bottles, whereas contents of all other elements were relatively not affected.
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Judul: Efektivitas Campuran Poli(Aluminium Klorida) (PAC) dan Aluminium Sulfat (Tawas) sebagai Koagulan dalam Pengolahan Air Bersih
Abstrak: Poly(aluminum chloride) (PAC) and aluminum sulfate (alum) are commonly used coagulants for water treatment. This study aimed to determine the effective coagulant dose of PAC and alum mixture Cisadane river water treatment. Coagulant mixture ratio used were 100:0, 75:25, 50:50, 25:75, and 0:100 with low and high levels of water turbidity. In addition to turbidity, effectiveness in decreasing the Fe, Mn, and organic substances contents were also studied. PAC was more effective in decreasing the levels of turbidity (88.29%), Fe (76.03%), Mn (75.57%), and organic substances contents (41.74%) compared to the other coagulant mixtures. In terms of cost, 75:25 ratio of PAC-alum coagulant mixture was more efficient under condition of high turbidity level.
Keyword: alum, aluminum sulfate, poly(aluminum chloride), PAC, turbidity

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