Calibración de Fotodiodos OPT101

Antes de comenzar a trabajar en depósito químico hace dos semanas estuve trabajando en la calibración de fotodiodos para poder colocar un piranómetro de bajo costo en base de los opt101.

Lo último que realicé fue la calibración, y un prototipo en PVC del cuerpo del instrumento.

Aquí les presento los datos recolectados para la calibración

Se puede observar que la correlación que más se aproxima a los datos experimentales es una curva cuadrática del tipo polinomial.

How to add math on your blog : MathJax + Blogger

This tip is useful for engineering and science bloggers who want to share their knowledge on the web. Here is the way I found. I recently tested it on the blogger system,  the purpose is to share science tutorials with you using the correct math way.

Let's do it!

Draft on paper of the Debye-Scherrer equation for crystal size calculation 

Step 1: Add a new gadget to your blog and copy and paste the following script.

<script src="https://polyfill.io/v3/polyfill.min.js?features=es6"></script>
<script id="MathJax-script" async src="https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-mml-chtml.js"></script>

Step 2: Write code in a new post following using latex language inside:

• Inline \( latex code here \)
• Paragraph  \[ latex code here \]

Step 3: Equation test: Debye -Scherrer  for crystal size calculation
$$D(\text{nm})=\frac{0.9\lambda }{\beta \cos \theta }$$

• D: Crystal size 
• $\lambda$ : 0.15406 nm  X-Ray wavelength 
• $\beta$ :  FWHM in radians (Full width at half maximum)  
• $\theta$ : Angle location of the peak in radians. 

If you have any questions, please comment on the post.

Samples from : https://www.mathjax.org/#samples

• The Quadratic Formula

$$x=\frac{-b\pm \sqrt{b^2-4ac}}{2a}$$

• Cauchy's Integral Formula

$$f(a)=\frac{1}{2\pi i}\oint \frac{f(z)}{z-a}dz$$

• Angle Sum Formula for Cosines

$$\cos (\theta +\varphi )=\cos (\theta )\cos (\varphi )-\sin (\theta )\sin (\varphi )$$

• Gauss' Divergence Theorem

$${\int }_D(\mathrm{\nabla }\cdot F)dV={\int }_{\partial D}F\cdot ndS$$

• Curl of a Vector Field

$$\overrightarrow{\mathrm{\nabla }}\times \overrightarrow{F}=(\frac{\partial F_z}{\partial y}-\frac{\partial F_y}{\partial z})\mathbf{i}+(\frac{\partial F_x}{\partial z}-\frac{\partial F_z}{\partial x})\mathbf{j}+(\frac{\partial F_y}{\partial x}-\frac{\partial F_x}{\partial y})\mathbf{k}$$

• Standard Deviation

$$\sigma =\sqrt{\frac{1}{N}\sum _{i=1}^N(x_i-\mu {)}^2}$$

• Definition of Christoffel Symbols

$$({\mathrm{\nabla }}_{X}Y{)}^k=X^i({\mathrm{\nabla }}_{i}Y{)}^k=X^i(\frac{\partial Y^k}{\partial x^i}+{\mathrm{\Gamma }}_{im}^k{Y}^m)$$

Exploring the XRD system at IFUAP

A scientist is continuously seeking the truth of nature. There is a jungle of fields to explore from material science to the universe, a scientist could be doing experiments at the laboratory, or maybe they just need a comfortable place to think and create new theories which will explain new phenomena. 

Training day: XRD System  and software High Score Plus, BUAP

Today I was able to explore the XRD system at IFUAP (shown in the above picture). The purpose of this visit was to analyze a previous measured XRD pattern. Gratefully the responsible researcher allows me to manipulate the software High Score Plus to perform a qualitative analysis to identify the phases in the material.

High Score plus, performing phase analysis, and calculation of crystal size.

To identify the phase three steps should be performed in the following sequence:

1. Background determination: This is a must step due phase analysis depends on it.
2. Peak search: Automatic + Manual is the best
3. Phase analysis: Should be restricted to the constitutive elements to gain time. In my case, the restriction increase using just inorganic materials and star quality powder diffraction files (PDFs) from the database.

Once these three steps are done, the analysis gives you three important values: 

• Background: This information is necessary to make a good report where the background should be extracted from the observed XRD measurement.
• Constitutive phases: This data confirms if your material is pure or is mixed
• Crystal size: This parameter gives the size domain D < 100 nm makes you think in the nanoworld.

If you want to know how the XRD system works  watch the following video: 

Have you ever seen an XRD system with your own eyes?