Even though cooling crystallization and anti-solvent crystallization are convenient, it has major drawbacks in terms of slow rate of crystallization, high supersaturation degree , solvent and anti-solvent selection based on solubility. Some of the newer methods for crystallization include ultrasound assisted (UA) cooling crystallization , UA anti-solvent crystallization  and melt sonocrystallization , . Ultrasound based approach has been found to initiate nucleation at lower supersaturation. Reduction in induction time has been observed in most of the APIs when the supersaturated solution is subjected to ultrasonic irradiation
The separation efficiency of SCOT columns is higher than WCOT columns due to the greater surface area of the stationary phase coating. In FSOT column, the walls of capillary fused silica tubes are strengthened by a polyimide coating. This type of capillary column is flexible and can be wound into coils. All of these three types of capillary column are more efficient than packed
CZE, also known as free solution capillary electrophoresis, is a separation technique that predominantly takes into account the ratio of the particle’s charge to mass, where those with large charge to mass ratio separate from the rest first; therefore, the larger the ratio, the quicker the separation. In addition to the electrophoretic mobility of the molecules, CZE is heavily dependent on the application of constant field strength throughout the capillary and on the pH of the buffer solution. CZE is an excellent choice of technique to employ in cases where there are very small pI (isoelectric point) differences in protein
This was first done by Italian chemist, Piria (1839). Salicin hydrolyses in aqueous media to form glucose and salicylic alcohol (saligenin). Salicylic alcohol is then oxidised to form salicylic acid. (Schrör 2010) Another natural source of salicylic acid is methyl salicylate present in wintergreen oil. Salicylic acid is obtained by hydrolysing methyl salicylate, an ester under basic conditions.
Sakka and co-workers first employed sol-gel method to prepare HAp. It is well recognized that sol-gel techniques have several benefits for producing ceramic particulates amid high purity, high crystallinity, and controllable grain size with good scalability. Sol-gel process, though, has a few drawbacks such as the need of costly precursor resources and little homogeneity of the finishing product. We report, herein, a cost effective sol-gel method for the gram-scale synthesis of hydroxyapatite nanoparticles using inexpensive starting materials of less toxicity. 5.1.2
The hydrolysis formed salicylic concentration which was mixed with iron(III) solution to form a purple complex. This was then use to study under the UV/Visible absorption spectroscopy which gave absorbance values recorded at 525nm to determine the concentration of salicylic acid using the Beer Lambert’s Law and later corrected to find the actual concentrations. The concentrations of aspirin at various intervals was found from salicylic concentrations. Upon plotting a graph of ln(aspirin) vs time, it produced a linear equation from which the gradient gave the rate constant of 0.0083min-1 and the overall shape of the graph concluding this reaction to be pseudo first order with respect to the concentration of aspirin with the deviations and improvements as
As can be seen in Fig.4, a higher ratio of p-xylene to methyl acetate can produce higher selectivity of acetic acid against water. It showed the positive influence of the high amounts of p-xylene on the selectivity. This is coherent with the idea that adding p-xylene into methyl acetate as a mixed solvent could lead to enhance the values of capacity of extraction and selectivity of acetic acid against water. This result showed p-xylene is powerful enough to be considered as the feasible solvent when mixed with methyl acetate. Likewise, the use of p-xylene
One of the reasons why SPE is a suitable technique for this analysis is the fact that there should be higher recoveries (% recoveries)since both caffeine and theophylline are polar compounds, with theophylline being more polar than caffeine which tells us that caffeine will have the longer retention time than theophylline. Other reasons include advantages such as SPE provides cleaner extracts and is easier to automate compared to other extraction
The chromatography term is derived from a Greek word Chromo for color and Graphe for writing. Chromatography is a separation technique based on the partitioning behavior. The concept of chromatography was introduced by a Russian botanist Mikhail Tswett in 1906. In this technique solute of interest is partitioned between two phases i.e. a mobile phase and a stationary phase depending on the partitioning value.
The Grove - Gas Sensor (MQ2) module is useful for combustible gases. And most of the pollutants are combustible gases. MQ2 is very reliable device because of its wide detecting scope, fast response and high sensitivity. Since the researchers needed numerical data for the quantitative research, Arduino was altered. It was originally programmed to indicate only the levels of health concern which includes Good, Moderate, Unhealthy for Sensitive Groups, Unhealthy, Very Unhealthy, and Hazardous.