Updated:

Nuclear Engineering: Atomic and Molecular Structure Report

Exclusively available on Available only on IvyPanda® Made by Human No AI

Introduction and Background

Nuclear systems present a wide scope of radiations drawn from various particle and rays present within the system. To this end, it is highly probable that such particles as alpha, beta and neutrons together with gamma rays are always present in a given nuclear system. While most of these particles lose their energies owing to nuclear interactions and individual scattering events, gamma rays are relatively different. Comparatively, these rays penetrate matter with ease and, on impact they interact with matter through Compton scattering, photoelectric effect and pair production. Vitally, once they penetrate matter it is apparent that the intensity of the rays decreases. As such, this drives us to ponder how both the absorber and the rays correlate.

Basically, since an absorber affects the intensity of the exiting rays then it follows that the magnitude of a ray is a function of the absorber thickness. Consequently, this can be represented as below mathematically:

I = I0·eµx (Lehmann 34) (1)

Where; I, I0, µ and x represent the intensities after and before interaction, the attenuation coefficient and the absorber thickness respectively. This can be simplified by the introduction of natural logs to:

Ln (I/I0) = -µx (2)

When the quotient of this ratio results to 0.5 then the thickness responsible for this is referred to as the half value thickness (x).

Description of Experimental Setup

The setup in this experiment is as shown below:

(Fig 1). (Radium 750-1000 No Chiclig)
(Fig 1). (Radium 750-1000 No Chiclig)

List of Equipment Used

The below is a list of all the raw material and equipment used:

Source (Radium 750-1000 No Chiclig), Absorber (Aluminum sheets 2.5 cm thick), detector (6B *Gas filled * 12-4-97).

Procedure

The equipment was arranged as is in figure 1 above and hence ready for analyses. The detector was then turned on prior to the commencement of the experiment, the rational being to record the background counts vital in eliminating experimental errors due to background sources. The source was then placed at a distance of approximately 3 cm from the detector and, prior to placing an absorber, the detector reading was given a moment to stabilize. This was then followed by placing an absorber between the sources and the detector before a gross count reading was taken and recorded. While maintaining the same position, sheets of aluminum were added momentarily while taking the detector readings until the readings were 25% that of the initial reading. The results were then plotted on a semi-log paper for analysis.

Similarly, while maintaining a similar position to that of the aluminum plate, a wooden absorber 1 cm thick underwent the same procedure and, later, the results were compared.

Data

Table 1: showing natural log of the original intensity I0 and the thickness (x) of the absorber (Aluminum).

Ln I0Thickness x (cm)
5.4162.5
4.6055
3.1927.5
2.30310

Table 2: showing natural log of the original intensity I0 and, the thickness (x) of the absorber (Wood).

Ln I0Thickness x (cm)
5.31
4.832
3.93
34

Analysis of Data

The raw data was manipulated using the formula below (3) after the introduction of natural logarithm on either side of equation (1). The intensity of radiation is a function of the thickness x of the absorber hence the equation;

I = I0·eµx (Lehmann 34) (3)

Introducing natural logs:

Ln I – LnI0 = µx (4)

Rearranging:

Ln I0 = -µx + Ln I (5)

As such, the gradient m = -µ and, the y-intercept = Ln I.

From the graph the background count was found to be 25 cpm and, the half value thicknesses was calculated courtesy of the information obtained from the plots i.e. the values of the attenuation coefficient µ. For the aluminum and wood these values were found to be 1.6 1 and 0.89 centimeters respectively. To obtain the half-thickness for aluminum the below formula is applied:

x1/2 = 0.693/µ

But; the attenuation coefficient of Aluminum µAl = mAl = -0.43

formula

As portrayed by the linear equations, the values for the gradients otherwise µ for both the aluminum and wood are -0.43 and -0.78 respectively.

Of natural log of the original intensity (I0) against the thickness (x) of the absorber (Aluminum).
Graph 1: Of natural log of the original intensity (I0) against the thickness (x) of the absorber (Aluminum).
Of natural log of the original intensity (I0) against the thickness (x) of the absorber (wood).
Graph 2: of natural log of the original intensity (I0) against the thickness (x) of the absorber (wood).

Discussion of Results

The objective of this experiment was to investigate the shielding effect of different materials. This was achieved using a gas-filled detector. From the analyses done it is evident that the half value thicknesses for both aluminum and wood were 1.61 and 0.89 cm respectively. In order to obtain this, it was necessary to extrapolate the graph beyond the count rate data to establish the original intensity of the two. However, with Excel, you can get this from the formula. In this case, when comparing the two, a 1 cm thick, wooden plate is a better shielding material than a 2.5 cm thick, Aluminum plate.

As portrayed by the linear equations, the values for the gradients otherwise the µ for both aluminum and the wooden plates are 0.43 and 0.78 respectively. As such, as opposed to the wooden plate, gamma rays easily penetrate the aluminum plate.

To improve on the accuracy of the results then future experiments need to be performed in an enclosed environment and, concurrently rather than subsequently.

Conclusions

The objective of the experiment was met and hence; it was established that a 1 cm thick, wooden plate is a better shielding material than a 2.5 cm thick, Aluminum plate.

Reference

Lehmann, Walter. Atomic and Molecular Structure: the development of our concepts, San Francisco: W.H. Freeman & Co., 1972. Print.

More related papers Related Essay Examples
Cite This paper
You're welcome to use this sample in your assignment. Be sure to cite it correctly

Reference

IvyPanda. (2022, May 11). Nuclear Engineering: Atomic and Molecular Structure. https://ivypanda.com/essays/nuclear-engineering-atomic-and-molecular-structure/

Work Cited

"Nuclear Engineering: Atomic and Molecular Structure." IvyPanda, 11 May 2022, ivypanda.com/essays/nuclear-engineering-atomic-and-molecular-structure/.

References

IvyPanda. (2022) 'Nuclear Engineering: Atomic and Molecular Structure'. 11 May.

References

IvyPanda. 2022. "Nuclear Engineering: Atomic and Molecular Structure." May 11, 2022. https://ivypanda.com/essays/nuclear-engineering-atomic-and-molecular-structure/.

1. IvyPanda. "Nuclear Engineering: Atomic and Molecular Structure." May 11, 2022. https://ivypanda.com/essays/nuclear-engineering-atomic-and-molecular-structure/.


Bibliography


IvyPanda. "Nuclear Engineering: Atomic and Molecular Structure." May 11, 2022. https://ivypanda.com/essays/nuclear-engineering-atomic-and-molecular-structure/.

If, for any reason, you believe that this content should not be published on our website, please request its removal.
Updated:
This academic paper example has been carefully picked, checked and refined by our editorial team.
No AI was involved: only quilified experts contributed.
You are free to use it for the following purposes:
  • To find inspiration for your paper and overcome writer’s block
  • As a source of information (ensure proper referencing)
  • As a template for you assignment
Privacy Settings

IvyPanda uses cookies and similar technologies to enhance your experience, enabling functionalities such as:

  • Basic site functions
  • Ensuring secure, safe transactions
  • Secure account login
  • Remembering account, browser, and regional preferences
  • Remembering privacy and security settings
  • Analyzing site traffic and usage
  • Personalized search, content, and recommendations
  • Displaying relevant, targeted ads on and off IvyPanda

Please refer to IvyPanda's Cookies Policy and Privacy Policy for detailed information.

Required Cookies & Technologies
Always active

Certain technologies we use are essential for critical functions such as security and site integrity, account authentication, security and privacy preferences, internal site usage and maintenance data, and ensuring the site operates correctly for browsing and transactions.

Site Customization

Cookies and similar technologies are used to enhance your experience by:

  • Remembering general and regional preferences
  • Personalizing content, search, recommendations, and offers

Some functions, such as personalized recommendations, account preferences, or localization, may not work correctly without these technologies. For more details, please refer to IvyPanda's Cookies Policy.

Personalized Advertising

To enable personalized advertising (such as interest-based ads), we may share your data with our marketing and advertising partners using cookies and other technologies. These partners may have their own information collected about you. Turning off the personalized advertising setting won't stop you from seeing IvyPanda ads, but it may make the ads you see less relevant or more repetitive.

Personalized advertising may be considered a "sale" or "sharing" of the information under California and other state privacy laws, and you may have the right to opt out. Turning off personalized advertising allows you to exercise your right to opt out. Learn more in IvyPanda's Cookies Policy and Privacy Policy.

1 / 1