In this work, two families of catalysts based on mixed metal oxides derived from MgAl hydrotalcites were synthesized with a Mg/Al molar ratio 3. On the one hand, in first family, fluoride anion was incorporated interlayer space by using ammonium fluoride, exploiting “memory effect” characteristic hydrotalcites. second anions substituted layer, incorporating directly them during precipitation hy...

aquatic animals are important resources for extraction of valuable compounds such as enzymes. in this study, lipase was extracted from the intestine of rainbow trout. samples were defatted with acetone several times; ammonium sulphate (60%) was used for precipitation followed by ultrafiltration for concentrating the samples. the final purification of the enzyme was performed by passing of the s...

Process safety, as well as the safe storage and transportation of hazardous or reactive chemicals, has been a topic of increasing interest in the last few decades. The increased interest in improving the safety of operations has been driven largely by a series of recent catastrophes that have occurred in the United States and the rest of the world. A continuous review of past incidents and disa...

Silicon nanowires (SiNWs) were fabricated by metal-assisted chemical etching (MACE) where hydrofluoric acid (HF), which is typically used in this method, was changed into ammonium fluoride (NH4F). The structure and optical properties of the obtained SiNWs were investigated in details. The length of the SiNW arrays is about 2 μm for 5 min of etching, and the mean diameter of the SiNWs is between...

With the idea of finding a more selective radiotracer for imaging herpes simplex virus type 1 thymidine kinase (HSV1-tk) gene expression by means of positron emission tomography (PET), a novel [¹⁸F]fluorine radiolabeled pyrimidine with 4-hydroxy-3-(hydroxymethyl)butyl side chain at N-1 (HHB-5-[¹⁸F]FEP) was prepared and evaluated as a potential PET probe. Unlabeled reference compound, HHB-5-FEP,...

By using an ionic liquid of 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, we uniformly dispersed single-walled carbon nanotubes (SWNTs) as chemically stable dopants in a vinylidene fluoride-hexafluoropropylene copolymer matrix to form a composite film. We found that the SWNT content can be increased up to 20 weight percent without reducing the mechanical flexibility or softnes...

The synthesis, radiolabeling and in vitro evaluation of new silicon-fluoride acceptor (SiFA) derivatized D(2)-receptor ligands is reported. The SiFA-technology simplifies the introduction of fluorine-18 into target specific biomolecules for Positron-Emission-Tomography (PET). However, one of the remaining challenges, especially for small molecules such as receptor-ligands, is the bulkiness of t...

Rifampisin merupakan salah satu obat anti-tuberkulosis. HPLC metode pilihan karena kepekaan, reprodusibilitas dan spesifitasnya. Namun terbaru dari kromatografi cair membutuhkan penambahan tetra-butyl ammonium hydroxide yang dapat memperpendek umur kolom. Penelitian ini bertujuan untuk mengembangkan suatu dengan waktu pengerjaan efisien dibandingkan metode-metode sebelumnya. Sistem yaitu Allian...

In this report, dysprosium fluoride (DyF3) - a material for the preparation of (Dy) metal was prepared by fluorination oxide (Dy2O3) ammonium bifluoride (NH4HF2) reagent. The effect reaction time and temperature on formation salt has been studied. phase composition crystal structure obtained products were analysed X-ray diffraction (XRD). Thermal analysis techniques applied to determine range f...