apex chemical essay

is accumulated in cells shifted to higher temperatures; it seems that the disaccharide represents a stress response product. In addition to being non-reducing, it possesses several unique physical properties, which include high hydrophilicity and chemical stability and the absence of internal hydrogen bond formation. Due to its unusual physical features, trehalose is able to protect the integrity of the cell against a variety of environmental injuries and nutritional limitations. These characters

Rhenium, pronounced REE-nee-em, was the last naturally occurring element to be discovered. It was found by the German chemists Ida Tacke-Noddack, Walter Noddack and Otto Carl Berg in the year of 1925 (Rhenium - Element Information). They named the element after the Rhine River river in Germany since that was the country of which they were from. Rhenium does not have any other aliases which is why its element symbol of “Re” is not very different from its actual name. It holds the atomic number of

Residual solvents are defined as organic volatile impurities that may remain in active Pharmaceutical substances, excipient or medicinal products after processing. During the manufacturing processes, the solvents are not completely removed. The solvents may be used to improve the yield in the synthesis of active pharmaceutical substances besides imparting characteristics of crystal form, purity and solubility. Residual solvents do not have any therapeutic effect. Therefore, efforts should be made

Iron is a chemical element with the symbol Fe and atomic number 26. It has a melting point of 1,538 °C and a boiling point of 2,862 °C. The term ferric refers to any compound or material containing iron. The oxidation numbers 2+ and 3+ denote the chemical structure of the ferric compound. [11] By its mass, iron is the most common element on earth forming much of the inner and outer core of the planet. Iron is the most abundant transition metal in the body. It is involved in many bodily functions

Quinazoline nucleus is an essential building block. This nucleus can be found in a huge number of natural products as well as synthetic derivatives [1]. From the chemistry point of view, quinazoline can be considered as a benzo [d]pyrimidine heterocyclic fused ring. 4-Aminoquinazoline derivatives, an important class of heterocyclic compounds [2], which have shown broad variety of biological activity profiles, e.g. anticancer [3-5], antimalarial [6], antimicrobial [7], and antiviral activities [8

"Stem cells?" "Yeah, they're blank cells, and you can manipulate them to become almost any type of cell you want." My brother was picking me up from school and I asked him how he was doing in school. At the time, I was in seventh grade and my brother had started his first semester at the community college, he told me about a research paper he was writing on stem cells. He briefly explained that stem cells were "blank" cells that are transformed into a specialized cell. I was unable to comprehend

In Chemistry, when a student conducts their experiment and is asked to calculate the percent yield for their reaction it may be possible that they can get either a low percentage yield or a high one even above 100%. The first thing they need to understand what a percent yield is to begin with. A percent yield is calculated to be the experimental yield divided by theoretical yield multiplied by 100, basically it is the total amount of product that could be created in a reaction, calculated referring

2) Correctly position the impact tip in the center of the head and establish the zero point before impacting. Unlike open head injury, the impact tip positioning is relatively difficult. First, the size of the impact tip and the impact center affect the injury degree and lesions. An optimized 9mm tip is used in this protocol. Based on mouse brain anatomy, the impact center is designed to correspond to the central sagittal suture midway between coronal and lambdoid sutures. To positioning a correct

Upon contact of the core-in-cup tablet with medium, those plug layers, comprising of SA, NaCMC and HPMC, absorbs water. Consequently, those polymer swells and stretches. As the contact time increases, the swelling of the plug further extends, builds a obstruction which postpones the contact of fluids with the surface of the core tablet. It may be additionally suggested that the swelling of the plug layer might destabilize the plug itself gradually bit by bit prompts its disintegration or evacuation

My work this semester involved the continued study of the rhodamine spirolactam derivative that I synthesized in the previous semester. This rhodamine derivative is a photoactivateable dye, and exposure to 405 nm light converts the closed form of the dye to a fluorescent open form (Figure 1). This open form can then be excited with green light (510-565 nm) to observe fluorescence emission in the range of 570-650 nm1. An interesting additional consideration is the effect of pH on the stability