Chemistry Dissertations | Free Dissertations on Chemistry

Supercritical Fluids (SFCs) / Supercritical Fluid Extraction

Published Date: 08 Feb 2018

27 Pages (10,413 Words)

I. ABSTRACT (ENGLISH) The experimental determination of the yield of pyrethrins from the Chrysanthemum cinerariaefolium flower is usually carried out with Chromatographic Techniques. A lot of methods about this have been reported over the years [Z-M. ChertY.H. Wang (1996)]. These include HPLC [13 -22], GC [22-26] and SFC [B. Wenclawiak, A. Otterbach (2000) methods. Because of the need for only analyzing the pyrethrins (not reporting for ...

Click here to read more

Processes of Drugs Metabolism in the Body

Published Date: 08 Feb 2018

30 Pages (11,956 Words)

Abstract Metabolism of drugs is a complex and major process within the body, occurring primarily in the liver. The aim of metabolism is to make the drug more polar to enable excretion via the kidneys. The basic understanding of drug metabolism is paramount to ensure drug optimisation, maximum therapeutic benefits and a reduction in adverse effects. Essentially drug metabolism is broken down into two phases, Phase ...

Click here to read more

Literature Survey on Hydrogen Separation Technique

Published Date: 08 Feb 2018

26 Pages (10,012 Words)

Literature review has been performed in order to identify recent publications on hydrogen separation methods, hydrogen solubility, materials and concepts in research institutes and laboratories. The aim of the performed literature survey was to monitor recent worldwide literature and find out whether some of the developed and reported solutions might possibly help to improve existing hydrogen separation concept in PDh system, enabling efficient complete separation of ...

Click here to read more

High Performance Liquid Chromatography (HPLC) 214

Published Date: 08 Feb 2018

13 Pages (4,881 Words)

Introduction High performance liquid chromatography 214 is the most widely used of all of the analytical separation techniques. The reasons for the popularity of the method is its sensitivity, ready adaptability to accurate quantitative determinations, suitability for separating non-volatile species or thermally fragile ones, wide spread applicability to substance that are of prime interest to industry, many fields of science and the public. The applications of ...

Click here to read more

Physico-chemical Processes that Occur During Freezing

Published Date: 08 Feb 2018

38 Pages (14,847 Words)

1. Introduction Lyophilization respectively freeze-drying is an important and well-established process to improve the long-term stability of labile drugs, especially therapeutic proteins.[1] About 50% of the currently marketed biopharmaceuticals are lyophilized, representing the most common formulation strategy.[2] In the freeze-dried solid state chemical or physical degradation reactions are inhibited or sufficiently decelerated, resulting in an improved long-term stability.[3] Besides the advantage of better stability, lyophilized formulations ...

Click here to read more

Flow Cytometry for the Evaluation of Semen

Published Date: 08 Feb 2018

42 Pages (16,594 Words)

State of the Art in Sperm Assessment Using Flow Cytometry Abstract Flow cytometry is emerging as a substantial tool in the domain of modern andrology for the routine analysis of spermatozoa. Recent application of flow cytometry in the artificial insemination industry especially for pig is a new approach. Until very recent, analysis of semen samples was routinely performed by microscopical evaluation and manual techniques by laboratory ...

Click here to read more

Predicting Effects of Environmental Contaminants

Published Date: 08 Feb 2018

35 Pages (13,816 Words)

1.1. Debunking some chemical myths… In October 2008, the Royal Society of Chemistry announced they were offering £1 million to the first member of the public that could bring a 100% chemical free material. This attempt to reclaim the word ‘chemical' from the advertising and marketing industries that use it as a synonym for poison was a reaction to a decision of the Advertising Standards Authority ...

Click here to read more

Effects of Atmospheric Aerosols on Human Health

Published Date: 08 Feb 2018

39 Pages (15,467 Words)

Abstract: A highly Sensitive (LOD; 0.04-0.4 ng/ml) method is developed for detection and quantification of acidic compounds (C3 -C10) containing mono and dicarboxylic acids on GC-MS. These compounds (C3 -C10) existed in trace amount, as secondary organic aerosols i.e. important constituents of Aerosols. Membrane extraction technique was utilized for selective enrichment (1-4300 times) of target compounds. Good repeatability (RSD% ≤ 10%) from selective organic phase (10% ...

Click here to read more

Enantioselective Disposition of MDMA and its Metabolites

Published Date: 08 Feb 2018

30 Pages (11,800 Words)

INTRODUCTION Amphetamine-type stimulants (ATS) are a group of drugs, mostly synthetic in origin, that are structurally derived from β-phenethylamine (Figure 1). Amphetamine (AMP, "Speed") was initially synthesized in Berlin in 1887 as 1-methyl-2-phenethylamine. It was the first of several chemicals, including methamphetamine (MET, "Ice") and 3,4-methylenedioxymethamphetamine (MDMA, "Ecstasy"), which have similar structures and biological properties, and are referred to collectively as "amphetamines" (Cody, 2005). Since 1887, ...

Click here to read more