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Without a direct example, I'm not sure I can confirm whether our instrument is doing the same. DTA and DSC are closely related techniques, with the difference being that DTA measures temperature differences between a sample and a reference, while DSC measures heat flow differences between a sample and a reference. Since the SDT650 measures temperature through both the sample and reference beams, it is quasi-DTA. However, it isn't optimized for that technique so I wouldn't use it as such.

@@materialscharacterization4168 Thank you so much. Regards.

Unfortunately, we don't own either of those instruments, so we won't be doing those techniques.

We have done some clay samples in our XRDs. Collecting data for clay is rather simple. However, clay can contain several completely separate phases which overlay and make phase identification (not included in this video) rather complex. There are some procedures out there to help isolate certain phases. Google searching "Clay separations for XRD" can give you some good starting resources.

We don't currently recommend putting a slit in the reference beam location. Our "slits" are actually just thick pieces of magnet from which we've cut holes of different sizes. Because of their glossy surface, they do reflect some light, and can cause reflectance values greater than 100%. By narrowing the beam down in the transmission space, the beam that hits the reflectance side is also altered. If a person is interested in reflectance data, we recommend they turn on the "align" mode, then chose and position a transmission slit so that the beam hitting the back of the integrating sphere (in the R position) is the right size and shape for the sample in question.

Can you clarify - what do you mean by "adapters?" And for the deflectometer, are you asking about an extensometer (such as for tension/ compression tests) or a deflectometer (such as for flexture tests? Depending on the model of your adapters or deflectometer, I can try to assist.

Hi, our D2 Phaser came with several manuals ranging from quick start guides to more in-depth maintenance and operation procedures. May I ask what the manual is needed for? Is this something you've already contacted Bruker about without success?

We have had that same issue repeatedly on our instrument as well. In the past, depending on the age of the W bulb, changing that lamp can sometimes help smooth things in that area. I believe you can also experiment with the gain and response settings in the detector settings on the schematic page of the method setup. I don't have much experience with how to change those settings, but it has been recommended to us by Perkin Elmer. Since the detector and the monochromator change at the same time, adjusting the relevant detector can help smooth that noise as well

You're hoping to use BaSO4 as the reference material? There are a few ways to handle reflection baselines. The first is with the typical 100/0% baselines I talk about in the video (just after minute 30). When running those, put your BaSO4 material in the reflection port in place of the spectralon standard provided. To take it a step further, you can also use the Reflection Corrections section underneath the 100/0% baseline section. I don't have much experience with those corrections, but they would help you differentiate between a specular (like a mirror) or a diffuse (like BaSO4) reflector.

@@materialscharacterization4168 Yes, this is exactly why I ask. Thank you for answering. I basically wanted to record a baseline measurement with BaSO4 (use it as a reference) and then measure the sample, but I was confused about one thing. Should my sample be also mixed with BaSO4 (both in powder form of course) or does my sample not need BaSO4 for the measurement anymore after the baseline? In this case, what was the reason for the BaSO4 in the first place? Was it to let the detector know the maximum diffuse reflection it can get from the BaSO4 or for which reason exactly? I think this confusion comes from thinking about the UV vis as an extension to the KBr - FTIR measurement. I thought it would be the same principle with the sample being disperesed in a matrix of the background (The KBr).

@@mahmoudsorour2028 I can see how that would be confusing. The KBr and BaSO4 are working in completely different capacities here. KBr is invisible to IR light, which is why it's used in FTIR. BaSO4 is (nearly) 100% reflective (so the opposite of invisible) and is merely used to define where 100% lies. If you think in terms of physics, there's no such thing as "100% light." It has to be a relative measurement, and you're using BaSO4 as the reference point. Your sample should, usually, not be diluted with the BaSO4. Hopefully that cleared it up!

@@materialscharacterization4168 All clear now. Thank you so much for your time. Appreciate it. I thought about it today in the morning and reached the same conclusion. Glad to have the confirmation from you. Thank you again and have a nice one!

You can find our hourly rates for using the equipment at mcl.mse.utah.edu.

Are you interested in setting up a method, or installing the fixture? We use the www.instron.com/en/products/testing-accessories/flexure-fixtures/three-point-bend-test-fixtures?region=Global%20Site fixture in our lab; is that the same one you're interested in learning about?

Yes, that's what many choose to do. Some do prefer to do the subtraction themselves, so they'll run empty as the background, then run the reference KBr pellet as sample 1, then run the sample KBr pellets. I find that to be more work for an equal return, but it's up to the researcher.

Hi Ricardo, I'm sorry to hear that your computer crashed. We purchased our (Windows 10) software in 2020 from Perkin Elmer. I know they don't directly support some aspects of the Lambda 950 anymore, but they still make WinLab for their other Lambda series (850 and 1050). You should be able to reach out to them to purchase a new license for your machine. Since we paid for our license, I don't feel comfortable sharing it outside of our lab. Best of luck!

I know most XRD machines have the capability to calibrate the instrument, but I'm not familiar with the procedure for doing so on the D2 Phaser. We do regularly run a NIST Si line standard (every 3-4 months) which we use to calculate the offset of the instrument. The D2 Phaser remains pretty consistent from month to month.

Hi Nisar. Are you hoping to learn about how to connect different gasses to the machine (so the software recognizes them) or what analysis parameters to use for different gasses? I have used argon on our instrument, so I may be able to help guide you in the right direction!

@@materialscharacterization4168 That's great news...and Thank you very much for your kind reply...that will indeed will help me

@@MrNisarB Does that mean you need to learn both? Do you have access to the 3Flex manual?

Thank you for the kind words! Best of luck with your work!

We don't have an 8801 here, so I'm not sure about its specifics. But if you're using Bluehill Universal, you'll likely be doing either a creep method or a test profiler method. Creep methods are best for pulling (or pushing) to a certain displacement (or force) then holding the sample there for a set amount of time. This will measure the amount of displacement or force relaxation in the sample over time. A test profiler method is much more versatile, and would allow you to do things like cycles of tension, holds, and compression. We recently completed a test that ran 10,000 cycles of compression. There are some software limitations (we were unable to track the displacement at each of the 10,000 maximum forces), but we used a secondary software to do the final analysis on the actual fatigue over the multiple cycles. Hope this helps somewhat!

Hi, glad you liked the video! I'm not sure I know what you mean by "finding peaks options." If you mean analysis software that can identify the peaks and do matching, we use Match! Crystal in our lab. We have used HighScore Plus in the past. There are many other options, though, that range from expensive to free. GSAS is a common one that our students use. It's free, but requires some python programming knowledge.

Hi. TA (the manufacturer) recommends calibrating their instrument approximately every month. Calibration includes running known, high-purity standards to ensure the detectors are reporting the correct temperature, weight, and power values when a sample is being run. TA also recommends that if you change the pan type, gas type, gas flow, or heating rate, that you recalibrate. Each of these changes can affect how the machine detects power, temperature, and weight changes, and could potentially invalidate the calibration that was done previously. In my experience, changing gasses does not invalidate the calibration to a large degree. We regularly switch back and forth between air, nitrogen, and forming gas. We run all of those with our "Nitrogen" calibration and get little perceptible error. If you require a high degree of certainty in your results and your calibration is done with nitrogen, I recommend running a new calibration in air with the same parameters (pan type, heating rate, gas flow rate) as you wish to run your sample.

Hi! The basic principle is that T+A+R=100% of the light. If you assume there is no transmittance (T=0) then A and R can be directly equal. In the case of a thick pellet of powder, you can assume there is no light transmitted through the sample, so it should be ok to change between A and %R and have them both be correct. Just keep in mind that the machine is measuring %R and calculating A.

@@materialscharacterization4168 I've tried to measure and compare the same sample in two modes: A and R. The results showed that the peaks in the spectrum obtained in R mode are much wider than in A mode, however the positions of the peaks didn't change. Using Kubelka-Munk transformation makes the peaks even narrower. Which option, in your opinion, is more correct?

@@КонстантинГорбунов-ы7ц Without being involved in your analysis and knowing the parameters of your material and the machine you're using, I am unable to comment on which method is more correct. You would probably do best to find a materials-trained person in your research facility to discuss the results with them.

@@materialscharacterization4168 Thanks for the answer.

Thanks for your question! The purpose of running multiple scans to co-add is to reduce noise and increase the signal-to-noise ratio. In some cases where the results are being observed by a governing body (for example the FDA), they might require that the background and the samples have the same number of scans to co-add. However, we have found that it makes little to no functional difference in the research conducted in our lab.

Hi Mohammad - that tutorial is in the works. We're hoping to have additional material for all of our machines sometime in 2021.

@@materialscharacterization4168 Hi, Is there an integrating sphere underneath the URA ?

@@pattabhidyta7991 I am not 100% sure, but I don't think so. The URA uses a system of mirrors to reflect the light at incident angles between 8 and 65 degrees to the sample surface. I don't think it uses an integrating sphere to collect that data; I think it's more mirrors that direct the light to the detector.

@@materialscharacterization4168 Thank you. Also wanted to know, What would be the power output of the light through the transmittance port of the integrating sphere? Is it good enough to place a fruit (say an apple) ?

@@pattabhidyta7991 So sorry I didn't see this until now. I believe the Lambda 950 is meant to handle ~6 OD, which means that 1 photon for every 1,000,000 photons gets through the sample. If the slice of apple was thin enough to allow at least that much light through, it could be analyzed. Since the transmittance of light through an entire apple is 0, that would not be possible. In that case, a sort of reflectance measurement would be the best option.

Hi, so sorry we didn't see this comment sooner! Absorption can be measured using reflectance and transmittance, as you mentioned. Many times, users will make the assumption that one of those is nonexistent (such as with a very thick sample, there is little or no T). In that case, R and A would be inverse of one another. The same is true if you assume no R (A and T would be inverse). Those are the most common ways one could find exact absorbance with this machine.