Modification of Nanozirconia with Sulfuric Acid and Calcium Oxide as Heterogeneous Catalysts for Biodiesel Production from Used Coconut Cooking Oil

The commercial zirconia nanopowder was modified using sulfuric acid and calcium oxide to synthesize SO4/ZrO2 and Zr/CaO catalysts. The wet impregnation technique was utilized to obtain SO4/ZrO2 acid catalyst, and the Zr/CaO base catalyst was produced as well using reflux method through the microwave heating process. The highest total acidity of SO4/ZrO2 catalyst was treated by 0.9 M H2SO4 and 500 °C of calcination temperature, and this catalyst was succeeded in reducing used coconut cooking oil FFA from 1.18% to 0.42% in the esterification process. The highest total alkalinity was reached using 1% w/w Zr/CaO and 900 °C of calcination temperature, and this catalyst was applied in the transesterification stage and successfully converted used coconut cooking oil into biodiesel by 62.25%. The formation of biodiesel was confirmed by the presence of methyl laurate (50.48%), methyl myristate (19.05%), methyl stearate (11.05%), methyl 11-octadecanoic (6.09%), methyl octanoate (5.25%), methyl decanoate (5.05%), and methyl octadecanoate (3.03%)

Pengambilan keputusan manajerial instansi pemerintah

Data kunjungan pelayanan Hemodialisa di RSUD meningkat sejak tahun 2017 sampai 2021. Kebutuhan investasi alat kesehatan hemodialisa sangat penting untuk peningkatan pelayanan Kesehatan dan optimalisasi potensi pendapatan dari layanan ini. Namun, keputusan manajerial belum didasarkan pada analisis yang komprehensif sehingga perhitungan secara kuantitatif dan evaluasi secara kualitatif perlu dilakukan. Tujuan penelitian ini untuk memberikan pertimbangan kepada manajemen dalam pengambilan keputusan manajerial instansi pemerintah yaitu mengenai opsi membeli atau kerjasama operasi pengadaan alat kesehatan hemodialisa di RSUD X. Pendekatan penelitian yang digunakan adalah deskriptif dengan menggunakan data kuantitatif  dan evaluasi kualitatif. Unit analisis penelitian adalah  Unit Hemodialisa di Instalasi Rawat Jalan RSUD X. Hasil penelitian bahwa cost benefit analysis untuk nilai NPV opsi kerjasama operasi 0 yaitu sebesar Rp.3.160.603.300,32 dan positif, sedangkan nilai NPV opsi membeli 0 yaitu sebesar (-) Rp.7.751.854.763,93 dan negatif. Analisis cost benefit ratio, CBR opsi kerjasama operasi ≥ 1 yaitu sebesar 1,06, sedangkan CBR opsi membeli 1 yaitu sebesar 0,93. Singkatnya, usulan kerjasama operasi merupakan investasi layak diterima dan memberikan manfaat yang lebih besar dibandingkan dengan opsi membeli

A naphthalene-thiophene hybrid molecule as a fluorescent and logic gate with Zn2+ and OAc- ions as inputs: Cell imaging and computational studies

A naphthalene-thiophene hybrid molecule (Z)-1-((thiophen-2-ylmethylamino) methylene)naphthalen-2(1H)-one (HL) was prepared by condensation of 2-thiophenemethylamine and 2-hydroxy-1-naphthaldehyde. According to FTIR, 1H NMR spectrometry and single crystal X-ray analysis, HL exists in the cis-keto-amine tautomeric form. HL behaves like a molecular AND type binary logic gate with two inputs viz. Zn2+ and OAc- ions whereby the fluorescence of the system turns on. The structures of HL and its zinc acetate complex were also optimized by DFT calculations. HL binds Zn 2+ in a 1 : 1 ratio with an association constant Ka = 2.05 × 104 M-1, and detects Zn2+ as low as 3 × 10-8 M. HL is useful for the detection of intracellular Zn2+ under a fluorescence microscope. © The Royal Society of Chemistry 2013