Crystallization

Pharmaceutical synthesis involves various methods and techniques. These techniques are crucial and require profound knowledge and understanding of the chemistry and handling of drug compounds. A pharmaceutical drug (also referred to as a pharmaceutical, pharmaceutical preparation, pharmaceutical product, medicinal product, medicine, medication, medicament, or simply a drug) is a drug used to diagnose, cure, treat, or prevent disease.[1] Most drugs are natural: collected from sources such as…

Reading Notes – Week 8 – DYER-WITHEFORD: John Gould While I am still reflecting on Cyber-Proletariat: Global Labour in the Digital Vortex, and am not entirely finished reading the first five chapters, I have taken Dyer-Witheford’s main argument to (big surprise!) revolve around this idea of the vortex and how it is altering the middle class. Dyer-Witheford argues that capitalist production is best characterized as a spiral that is “self-expanding in value, taking the form of commodities,…

1a) Yes, there is a correlation between the structures and the observed volatilities of compounds in Step (1a) and Step (1b). In Step (1a), n-pentane had the highest vapor pressure because the compound evaporated the fastest. N-heptane had the second highest vapor pressure, followed by n-decane with the lowest vapor pressure. The molecular structure correlates with the volatility because of the molecular weight for each compound. N-pentane is the lightest compound, followed by n-heptane and…

Interaction of concentrated nitric acid and sulfuric acid generated nitronium ion which is electrophile. And methyl benzoate nitration is one of electrophilic aromatic substitution. Nitronium ion will reacts with protonated intermediate at the meta position. After NO2 substituted, it becomes arenium ion intermediate. Then, the remained product HSO4- will attack hydrogen then transfer the proton to methyl 3-benzoate. In the experiment, students placed around 12 drops of concentrated H2SO4 in…

attributed to the high melt temperature due to strong intermolecular interaction. 3. Another problem for PHB is the progressive decrease of its mechanical properties, such as tensile strength, because of secondary crystallization and gradual loos of plasticizers over time. The secondary crystallization that occurs during storage at room temperature forms new lamellae in the amorphous phase. It has a low nucleation density. Therefore, it forms large spherulites with cracks and splits, which have…

atmosphere with or without Fe or Ni powders.22 Kim et al.23 and Xie et al.24 synthesized Si3N4 nanowires by the reaction of silicon substrate and NH3 with Fe nanoparticles as the catalyst. Zhang et al. synthesized Si3N4 nanowires via the direct crystallization of amorphous Si3N4 (a-Si3N4) powder under high temperature in N2 flow25, but is not consistent with…

com/how-long-does-an-ice-sculpture-last/ What do you think that this means for crystallizations in general (since ice is crystallized water)? Crystallization is the physical transformation of substances like liquid, therefore, the water undergoes a physical transformation from water to crystallized water. These two are both the same substance; they are just in a different physical state (liquid to solid). Furthermore, this proves crystallization occurs as substances change from one state to…

1.3. AMORPHOUS STATE The amorphous state of solids is composed of molecules that have a disordered arrangement, which do not constitute to the characteristic of the crystal grid and, therefore, have zero crystallinity. The distribution of molecules in the solid amorphous form is not entirely random as it is specific to a gaseous state because it has a certain degree of order between neighboring molecules. Due to the lack of regulation and the absence of a crystal grid, compared to the crystal…

another filtration. - Do not let the solvent react with the substance, or resulting in loosing amount of desired compound during recrystallize process. - The solvent should have enough volatility in order for removing the sample after crystallization. It helps the drying process of the compound become easier and faster. [1] Why are crystals washed with additional solvent when collected? Why cold…

referencing to get the information. Facts; Glass-ceramics have an amorphous phase and one or more crystalline phases and are produced by a feature called "controlled crystallization" in contrast to a spontaneous crystallization, which is usually not wanted in glass manufacturing. They don’t find it ideal to have "spontaneous crystallization" because they cannot have a perfectly formed shape and it is ideal for engineers to obtain the shape they want. It is usually said that ceramics have an…