pH is one of the most important factors influencing removal efficiency of many chemical and biological reactions (19). Removal efficiency by the nano-catalyst with exposure to UV radiation was reported as 99.14%, while in the absence of nano-catalyst was 86.72%. The greatest removal rate was reported at pH=11 in the presence of the nano-catalyst as much as 90 mg/L, owing to the high concentration of hydroxyl radical in the solution (20) (p<0.05). These radicals play an important role in oxidizing organic contaminants (21).The advanced oxidation processes are based on hydroxyl radicals, causing oxidation and removal of contaminants (19, 20). pH has an important impact on contaminant molecules, the surface charge of nano-catalysts, and the mechanism of the degree of production of hydroxyl radicals (22). …show more content…
The study by Mendez et al in 2011 in Spain through UV/TiO2 process for removing fluoxetine indicated that photolysis of fluoxetine is justifiable only at alkaline pH. The UV/TiO2 process results in 50% removal of fluoxetine at initial fluoxetine concentration of 0.11 mM, pH=11, and time of 60 min. This was due to the fact that elevation of pH led to increased absorption of fluoxetine on TiO2 and oxidation of the contaminant by hydroxyl radicals (24), congruent with the results of this research. Elmolla et al studied photocatalytic removal of the antibiotics of amoxicillin, ampicillin, and cloxacillin from aquatic environments in 2010 in Iran. The greatest removal level was obtained at pH=11. They stated that at alkaline pH, more hydroxyl ions become available to the catalyst, thereby producing more hydroxyl radicals, culminating in oxidation of the antibiotic (25), consistent with the results of this
To begin the separation of the sucrose from the Panacetin, approximately 3 grams of Panacetin was transferred to a 125-mL Erlenmeyer flask. Added to the flask was 50 mL of dichloromethane to dissolve the Panacetin to aid in the separation. A fluted filter paper was used to filter the Panacetin and dichloromethane mixture by gravity using a glass funnel. The remaining filtrate was set aside than transferred to a separatory funnel and the substance on the filter paper was dried and weighed. The filtrate was extracted with 2 increments of 25-mL portions of aqueous 1 M sodium hydroxide. During this step the filtrate in the separatory funnel was shook and vented 3 times.
The makeup of a compound drastically changes its intermolecular forces (IMFs) with the polar silica gel of a TLC plate; this concept is responsible for the variability of Rf values observed throughout the course of lab. The weaker the IMFs, the further a compound will travel through the silica. For instance, ionic interactions are the strongest IMF, but were not present during this experiment. H-bonding IMFs had the greatest impact for our specific compounds. Resorcinol and 3-chlorobenzoic acid exhibited low Rf values, due to its ability to H-Bond to silica’s hydrogen donors and oxygens acceptors (See graph 1). Both were adept to strongly H-bonded to silica because the compounds contained at least 1 H-donor and 2 H-acceptors. Thus, stronger/more
In the experiment, the cyclohexanol solution is used to perform the dehydration process. Cyclohexanol is a six carbon aromatic hydrocarbon with 1 of the hydrogen atoms is substituted by 1 hydroxyl group, OH-. Through dehydration reaction, the hydroxyl group of cyclohexanol is removed causing formation of cyclohexene. Cyclohexene is a six carbon hydrocarbon with a single double bond. Cyclohexanol will undergo E1 elimination mechanism to form cyclohexene. This elimination reaction will cause the loss of a small H-X molecule from adjacent carbon resulting in formation of pi bond. All the E1 mechanism reaction will undergo a process known as heterolytic bond cleavage. The condition for this heterolytic cleavage to occur is when one atom leaves a compound with both of the original bond’s electrons. This will lead to formation of ions. For example, elimination of H-X from an organic compound involves the loss of a proton and a
Concentration response curves to methacholine showed leftward shift in asthmatic group compared to group C, but the curves of treated groups with dexamethasone and all concentrations of curcumin were shifted to right compared to group A (Fig. 4a). The EC50 value in group A was significantly lower than group C (p<0.001, Fig. 4b). The values of EC50 in treated groups with all concentrations of curcumin and dexamethasone were significantly improved compared to the group A (p<0.001 for all cases, Fig. 4b).
Stimulant medication for ADHD has evidence for safety and efficacy, however this does not rule out 30% of the population that does not respond to stimulants. Non-stimulants are very useful in these situations. Atomoxetine (ATM) is a norepinephrine transport inhibitor and was the first non-stimulant to be approved for use in ADHD. The daily recommended dose for children is 1.4mg/kg. The exact mechanism of action is unknown for ATM, however research suggests it is a selective inhibitor of presynaptic NOR transporters, therefore inhibiting reuptake of norepinephrine. Primarily, the CYP2D6 isoenzyme pathway hepatically metabolizes ATM and undergoes oxidation, forming the active metabolite 4-hydroxatomoxetine. The second metabolite
Ciprofloxacin is a fluorinated antibiotic which is used to treat different types of bacterial infections. There is significant concern that antibiotics and hormonal based medications particularly those found in the pill are effecting the breeding cycles of animals, in particular in the oceans. These chemicals are found in domestic waste and pass through waste water treatment facilities (WWTF) into the water ways. This experiment determined the ciprofloxacin concentration in the sea water at three locations in major city (See map below, red dots indicate locations, red arrow
Semi-Microscale Oxidation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
The MD I have been working with in clinic is married to a cardiologist who likes to use Trilipix (fenofibric acid). Is there any expected difference between fenofibric acid and fenofibrate? He claims that the LFT elevations (Liver Function Test) are much less with fenofibric acid compared to fenofibrate. This doesn’t make sense to me at all. Do you have any information that maybe I’m missing? Do you have any rationale to justify this?
Caffeine is a drug that affects the brain and acts as a stimulant to the central nervous system [3]. It is one of the most common substances found in chocolate, tea and coffee [1]. The purpose of this experiment was to determine how much caffeine are in tea leaves by extracting the source from tea bags and being able to identify its properties compared with a real sample of caffeine through thin-layer chromatography. Methylene chloride was used to extract the caffeine from the tea, and sublimation was used to purify the product. The product was then tested with TLC with an authentic caffeine sample, and an unknown sample to verify the purity of the product and to see whether the unknown contained caffeine.
The reason for this experiment was to distinguish an unknown sample utilizing strategies for preliminary classification tests, solubility tests, chemical tests, infrared (IR) spectroscopy, NMR which is nuclear magnetic spectroscopy, and orchestrating a derivative of the unknown. The outcomes demonstrate that the unknown was observed to be 9-Fluorenone.
Due to disinfection (microorganisms) and oxidation (e.g. taste and odour control, elimination of micropollutants, etc.), chlorine is commonly used in water disinfection processes (Gunten et al., 2006). However, under certain circumstances, oxidants can induce formation of potentially harmful by-products or transformation products due to their reactivity with micropollutants in water (Kranser et al.,
The high toxicity and carcinogenicity of DNP and Cr (VI) compounds makes it essential that these should be effectively removed from the wastewater streams thereby posing limitations on the conventional
According to World Health Organization (WHO) (2012), depression is a mental disorder which is characterized by loss of interest and enjoyment, guilty feeling, low self-esteem, decreased energy, low concentration and sleep and appetite disturbances. Those issues can become repeated, chronic and can lead to prolonged damages to one’s capacity to carry on with everyday tasks. In the worst cases, depression drives to suicide. Figure (1) shows populations more vulnerable to depression.
The removal of 4-chlorophenol from aqueous solution by Phanerochaete chrysosporium impregnated with Fe3O4 magnetic nanoparticles was experimentally investigated. Air floatation, an efficient solid liquid separation technique, was trialed out as a tertiary treatment technique for 4-chlorophenol removal, after biosorption with cetyl trimethyl ammonium bromide (CTAB) as surfactant. Consequences were so amazing that in addition to efficient solid liquid separation, percentage removal was maximized to permissible limits, got a concentrated overflow and highly clarified underflow. Influence of various working parameters like initial feed concentration, pH, biosorbent dose, equilibrium time, catalyst dose, liquid pool height, surfactant concentration
Nanoparticles are being used in a diverse range of products for multiple applications which increases the chances to contaminate the environment. Nanomaterial can be released accidentally or intentionally. Being released to air, soil and water NPs pose threat as they are very small particles and can float into air or get transported to another place through water. Soil contamination leads to accumulation for long time and further pollutes ground water (Tripathi et al. 2012). Among the applications coatings, paints, and pigments are quite important and have the highest possibility of being released into soil and water. Electronics and optics signify a major application, and NPs used are more likely to be disposed in landfills. Nanoparticles