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Abstract:Steam reforming of methanol for production of hydrogen can be carried out over copper based catalyst. In the work presented here, the catalytic properties of a CuO/ZrO 2 catalyst (8.5 wt%) synthesised by a templating technique were investigated with respect to activity, long term stability, CO formation, and response to oxygen addition to the feed. The results were obtained using a fixed bed reactor and compared to a commercial methanol synthesis catalyst CuO/ZnO/Al 2 O 3 . It is shown that, depending on the time on stream, the temporary addition of oxygen to the feed has a beneficial effect on the activity of the CuO/ZrO 2 catalyst. After activation, the CuO/ZrO 2 catalyst is found to be more active ( per copper mass) than the CuO/ZnO/Al 2 O 3 system, more stable during time on stream ( measured up to 250 h), and to produce less CO. Structural characterisation by means of X-ray powder diffraction (XRD) and X-ray absorption spectroscopy (XAS) reveals that the catalyst (as prepared) consists of crystalline, tetragonal zirconia with small domain sizes ( about 60 Angstrom) and small/disordered crystallites of CuO.

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Protection capacity of mosquito repellent ink from citronella (Cymbopogon nardus L.) and clove leaf oils (Syzygium aromaticum) againts Aedes aegypti AIP Conference Proceedings 1855, 020023 (2017) Abstract. The current tinting industries return to the use of natural dyes because of their characteristics including safe and environmentally friendly. Indonesia can widely promote the potential of natural colours due to the availability of abundant natural dye plants. One of the potential plants that generates blue colour is Indigofera tinctoria. This research was conducted to improve the quality and quantity of natural indigo dye for batik production that supports the environment sustainability. The indigo dark blue paste was produced by initial treatment of soaking in cold water for 48 hours. The 48 hours fermentation anaerobic conditions reached optimum temperature, due to time and pH were also met by nutrients. Aeration was done in ten minutes using an aquarium air pump to increase mixing in water immersion with solution of calcium oxide. Indoxyl in the fermented leaves of Indigofera tinctoria is easily oxidized by air in alkali solution that will form pigment indigo. In that condition, lime (CaO) can be used in the manufacture of indigo paste. In this study, the higher concentrated of blue colour was achieved by lesser amount of lime. The soaking treatment in cold water produced high amount of dyes rather than the initial treatment by both hot water and grounding the indigo leaves. Analysis were done by using UV-Vis Spectrophotometry which showed the value of absorbance. The sample that was soaked in 5 liters of water added by a kilogram of Indigofera tinctoria leaves and 15 grams of lime for 48 hours, obtained the highest absorbance or concentration level. The application of the indigo dyes with or without mordanting agent was also tested for colour fastness.

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ABSTRAKLatar belakang: Kualitas mikrobiologi makanan masih menjadi masalah pada keamanan pangan. Di Bali banyak terdapat pedagang makanan khas tradisional, salah satunya adalah lawar. Lawar tidak hanya disukai oleh masyarakat lokal, tetapi juga oleh wisatawan mancanegara. Pemeriksaan mikrobiologi terhadap lawar perlu dilakukan agar sesuai dengan standar kualitas makanan yang dapat mencegah terjadinya kasus traveler's diarrhea. Dalam mempersiapkan makanan khas tradisional sebagai food tourism maka diperlukan kajian mengenai kualitas pangan. Hal ini untuk memenuhi keamanan pangan sehingga mampu bersaing di pasar global. Penelitian ini bertujuan untuk mengetahui kualitas mikrobiologis dan higiene pedagang lawar di kawasan pariwisata Kabupaten Gianyar, Bali serta proses pengolahan yang baik. Metode: Penelitian ini merupakan studi analitik cross sectional dengan pendekatan kuantitatif dan kualitatif menggunakan alat ukur pedoman observasi, wawancara dan pemeriksaan laboratorium. Pengambilan sampel menggunakan teknik random sampling dengan jumlah sampel sebanyak 44 penjamah makanan dan 44 sampel lawar. Wawancaara mendalam dilakukan pada 6 orang pedagang lawar untuk mengetahui proses pengelolaan lawar yang baik. Pemeriksaan E.Coli pada sampel lawar dilakukan di Laboratorium Mikrobiologi Fak. Kedokteran dengan Total Plate Count (TPC) dan Most Probable Number (MPN) yaitu perkiraan jumlah kuman yang mendekati per 100 ml air. Hasil: Proporsi sampel lawar dengan E. coli positif sebesar 72,7%. Dari hasil observasi ditemukan bahwa higiene penjamah makanan dalam kategori kurang baik sebesar 72,7%, fasilitas sanitasi kurang memadai 59%, kebersihan lingkungan kurang 54,5%. Hasil analisis bivariat menunjukkan bahwa variabel yang bermakna berhubungan dengan kontaminasi E. Coli yaitu: higiene penjamah makanan (p=0,00), fasilitas sanitasi (p=0,00) dan kebersihan lingkungan (p=0,05). Simpulan : Proporsi lawar yang terkontaminasi E. coli masih sangat tinggi dan berhubungan dengan higiene penjamah makanan, fasilitas sanitasi dan kebersihan lingkungan.Kata kunci : lawar, kualitas mikrobiologis. Gianyar Bali. ABSTRACT

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