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Thanks for the reply. My question is more driven by getting an understanding on what does it mean when a polymer is above Tg and below Tm. Money, processing time etc. is not important for now. When read about it, polymers heated above Tg are no longer brittle and they can now be plastic...

Thanks for the reply. I get that mixing is possible when heated above the melting temperature but is it also possible when heated above the glass transition temperature but below the melting point? In real life the polymer will have some degree of crystallinity. In this case, is it necessary...

Same polymer, same glass transition temperature, same size, same everything. Regarding the size: >10 um to avoid strange effects at the nanoscale.

I am wondering if two polymer particles, of same kind, heated above Tg can be mixed, over time, if they are squeezed together. By mixing I mean that the surfaces of the two particles will mix into one after they are squeezed together. For simplicity let's assume that the polymer particles are...

Hello everyone Can someone help me out solving this integral: \begin{equation} S_T(\omega)=\frac{2k_BT^2g}{4\pi^2c^2}\int_0^{\infty}\frac{sin^2(kl)}{k^2l^2}\frac{k^2}{D^2k^4+\omega^2}dk \end{equation} Where $$D=g/c$$ According to this paper https://doi.org/10.1103/PhysRevB.13.556. The...

Hi MisterX Thanks for your reply. I do understand that the input and output of a system often have units. However, from your definition of the transfer function above you can rewrite like this: H(s)=K⋅G(s) Where K is the gain and has some units that are specifik to the system of interest. We...

Hi All Probably a very basic question. What are the units of the constants in transfer functions? It we take a look at the transfer function of a second order system we then have: H(s) = ω02/(s2+2ζω0s+ω02) ω0 is the natural resonance frequency and has a unit of rad/sec. ζ is the damping...

Hi I am trying to characterize a microscale resistive heater. In my Bode plot there is decay that is less than -20dB/decade indicating that there is a zero in the system. Anyone having an idea of what physical meaning a zero in a resistive heater has? Thanks.

Thanks for the replies. An OPA569 seems like a good option. I will go for it. Again thanks.

Thanks for your reply. By thermal I do mean thermal as in heating. An example of a thermal actuator operating at 10 kHz can be found in this paper, see figure 11: In depth characterization and control of AFM cantilevers with integrated sensing and actuation. I can't go into too much details...

Thanks for your reply. The problem/challenge is to get a high current at 100 kHz. Ideally I would like to drive my actuator using a DAQcard but a normal DAQcard is not capable of delivering a 2 A current. So it is my plan control the signal to some extend. At the moment my best option is a...

Well it is actually what I want to do. The actuators I am working with have a bandwidth of 3 kHz but at higher frequencies the amplitude starts to decrease as the time constant if the actuator is too long. However, by modulating the drive signal you can increase the bandwidth of the actuator...

Hi All I hope that someone can help me. I have this thermal actuator with a resistance of ~1 Ohm that I want to operate at high frequencies, up to 100 kHz. In order to get the right amount of actuation I need to pass 1-2 A through the actuator. Can anyone tell me what kind of circuit would be...

I want to find the best materials for passivating electrodes in ionic solutions.

Okay, thanks. Instead of testing every metal oxide there must be a way of finding those oxides that are most likely to be the best. Any idea of how to this?