How to Obtain High-Quality Data in Your Optical Measurements (S/N ratio, etc.)

this is why the S/N ratio is important! (image is from here) 

Good research constitutes three factors: (i) high quality of the data; (ii) effective presentation (including writing); and (iii) importance in the research context in the field. Data quality is the one you can easily enhance if you know how. It is sad to see low-quality data drag down your research quality.

All spectroscopy, including FT-IR, absorption, FL, even XRD, can improve the data quality of a signal-to-noise ratio based on the same principal, which is the topic of this post. One of the factors for such results is the smoothness of the spectrum, so I focus on telling how to obtain a smooth spectra (aka high S/N ratio)

 

This is what I mean by "good quality of data" image is from here

(1)    The longer exposure time, the better S/N ratio

The golden rule: If your S/N ratio is enhanced by the square root time you spend, i.e., if you spend four times longer, you will have a two times better S/N ratio. If you spend 100 times longer, you will have 10 times better S/N ratio.

(2)    You may compromise the data point

In reality, you may not want to spend 100 times longer for a measurement than usual. For many spectroscopic measurements, you may compromise the data point. For example, you may not need 0.01 nm resolution in gold nanocrystal absorption. In that case, it would be a nice call if you change the measurement setting to 1 nm resolution and spend 100 times longer for each point.

(3)    Why not use the measurement multiple times?

Via the same principal, if you overlap multiple measurements, you will have a similar effect to enhance the S/N ratio. For some instruments, you may not be allowed to expose a signal to a detector for such a long time. In that case, this strategy is useful.

Good luck on your smooth operation!

Foresee what you are going to see and write it down in advance in your experiment notebook.

This is a famous art trick. You may see an old woman’s side face in a drawing—or, if you change your perspective, you may see a young girl looking at the other side in the same drawing.

This famous optical illusion is called “psychological scotoma.” Once you determine how you see it, you will be stuck inside that perspective.

In your daily experiments, you will see A LOT of things. For example, when you synthesize your nanocrystals, you might see color changes. Even in the color change, there is a lot going on such as what was the starting, intermediate, ending, what is the spectrum, where is the peak top, how narrow is your peak, how is the optical density, etc.

Life is full of information, but, in experiments, you may want to get all the information. Problems may include an overwhelming amount of information, even in a simple experiment, and it is difficult to see what it is because of your psychological scotoma. There are two solutions for that: Be super mindful and remember all that happened—or you get prepared for the change. Instead of cultivating meditation and mindful skills, I chose the second one; again, the key is organization skills.

If we can foresee the result of our experiments in a quartz sphere, research is going to be easy...

Here are some tips to keep you organized:

1. Write down what you will expect  

What you are going to make is the form that you will fill in the result.

2. Also check the event list

Such as “the color was changed from blue to red after the injection.”

By writing it in advance, you will be keen on the observation.

3. Write any other things that you realized

By preparing for things to happen, you will realize yourself that you will be keen on them. Obviously, there is a lot going on if you are mindful.

4. In the end, conclude your experiments

You want to understand what you observed. As much as you observe, you will have more evidence to support your hypothesis. Probably thinking about it might give you another perspective that you want to observe carefully for the next reactions.

Good luck on sucking up all information from a mindful experiment!

Learning new things

I was not good at chemistry exams when I was a high school student. Chemistry in high school was a straight-up memorizing-demanding subject, and I did not understand why I needed to remember the name of atoms with which atomic number 2 was called helium, or that the color of flame that generates when you burn calcium was orange.

The beauty of being an adult is that you do not have to take an exam. Don’t get me wrong. You most likely have to learn things day by day whatever occupations you get. Especially in research jobs, i.e., the more you enjoy, the more curious you will be. (“The less you know, the better” is rarely applied to academic research.)

You want to learn things from reliable information sources, and you want to learn with less time. Here are several tips.

1.          Find a good paper. Use Web of Science, Google Scholar, and SciFinder frequently.

2.          Check the reliability of the paper. For example, you may check (i) the author (Is the corresponding author known in the field?); (ii) the paper itself (Is it well-cited? Is it in a well-recognized journal not like a predatory journal?); (iii) Is it fairly new and old? (If it is too new, the idea might not be tested; if it is too old, the idea might be already denied.)

3.          Use a textbook. Although it may not be updated to the latest research, it usually has more tested results. Books are useful.

4.          Save the information and make your own library for a topic. As far as it is organized, the more information you have, the sharper you will be.

5.          If it is a problem that you don’t fully understand at this point, take a note. It is going to be a waste of time if you just make sure that you don’t understand some things the next time you read the paper. Easy scratching makes a big difference.

Good luck on your “The more you know, the better!”