Judul: Identifikasi dan Pencirian Fisikokimia Gelatin dari Tulang Sapi dan Babi
Abstrak: Gelatine is a derivative product of protein isolated from collagen tissue of animal skins and bones. In this study, gelatines were isolated from bovine and porcine bones, identified and characterized for their physicochemical properties including proximate, viscosity, pH, and mineral contents, as well as functional group and characteristic amino acids composition analysis. Bovine and porcine gelatine isolates were not obtained in crystal form as their standard forms, which affected viscosity and gelling abilities of the gelatines. Low yield of gelatine isolates were due to the high remaining phosphorus content, causing incomplete collagen extraction. Functional group analysis showed the existence of amide A (3438 cm-1), amide I (1651 cm-1), and amide II (1454 cm-1) characterizing the functional groups bovine gelatine isolate. However, the existence of amide III (1245 cm-1) still showed the structure of unhydrolized tropocollagen. Analysis of characteristic amino acids composition showed higher glysine amount in bovine gelatine than that in porcine.
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Judul: Perbandingan Ekstraksi Gelatin Kulit Sapi Split dengan Proses Asam dan Basa
Abstrak: Gelatin is a protein derivative from collagen fiber contained in the skin tissue, bone, and cartilage. Bovine hide is potential to be used in gelatin industry because it contains high collagen fiber, i.e. 89%. The hide can be obtained from the slaughterhouse or tannery industry. Split leather from tannery industry has not been utilized optimally. Gelatin production process can be classified mainly into two processes, i.e. acid or base process. Acid process produced gelatin type A while base process produced gelatin type B. These processes are different based on solution type and soaking period. Acid process is performed by soaking the leather in HCl 1%for 24 hours, while base process is carried out by soaking the leather in Ca(OH)2 3% and NaOH 0.05% for 7 days. Parameters observed in this study were moisture content, ash, protein, fat, color, acidity (pH), gel strength, viscosity, and molecular weight. The yield of gelatin from tannery and slaughterhouse leather obtained in this study were 22.12% and 30.77% for gelatin type A, respectively, and 6.40% and 26.12% for gelatin type B, respectively. The characteristics of the gelatin, from tanning manufacture and slaughterhouse, had complied SNI (1995) and BSI (1975). Thus, tannery leather is a potential source for gelatin. The yield showed that the acid process was better than the base process, while based on properties such as the viscosity, molecular weight, and gel strength, the base process was better than the acid process.
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Judul: Alat Perekam Data Hujan dengan Mode Hemat Daya
Abstrak: Pengukuran intensitas hujan dapat dilakukan dengan beberapa pendekatan, seperti menggunakan perekam data hujan otomatis (automatic rain recorder). Data curah hujan yang terukur oleh tipping bucket akan tersimpan dalam SDcard setiap kejadian hujan terjadi. Penggunaan arduino sebagai komponen utama dipilih karena perangkat open source yang mudah dimodifikasi. Beberapa komponen arduino yang dapat dimodifikasi adalah ATmega dengan konsumsi daya sebesar 12 mA pada 3 volt serta 17 mA pada 5 volt. Adapun FTDI mengkonsumsi daya sebesar 20 mA pada 5 volt. Voltage regulator mengkonsumsi daya sebesar 38 mA pada 5 volt, 64 mA pada 9 volt, 103 mA pada 12 volt, selain itu led mengkonsumsi 1 mA pada 5 volt. Komponen yang dapat dihilangkan pada arduino antara lain FTDI, voltage regulator, serta led. Pengurangan komponen ini bertujuan agar daya tahan baterai menjadi 6.5 kali lebih hemat dibandingkan arduino standar. Setelah bagian bagian tersebut dihilangkan maka total konsumsi daya yang diperlukan oleh mikrokontroler on board arduino adalah 12 mA saat 3 volt dan 17 mA saat 5 volt saat mode kerjanya. Hasil pengujian menunjukkan bahwa pada penggunaan mode sleep lebih efisien daya dibandingkan mode power save. Mode sleep membantu cara penghematan daya pada pembuatan alat perekam data hujan Penggunaan metode ini jika diasumsikan kejadian hujan hanya terjadi selama tiga jam dalam sehari maka dengan menggunakan baterai sebesar 400 mAh dengan tegangan 3 volt maka alat perekam data hujan ini dapat hidup selama 15 Hari….
Keyword: Arduino, Power save, Rain, Automatic recorder, Tipping bucket, Geophysics and Meteorology, Rain fall, Model penakar hujan, Arduino promini, Arduino uno