Almost every lab uses pH, ion-selective and ORP electrodes. They are quite expensive, do not last much, and can be easily ruined.

On the other side, there are numerous electrode manufacturers, and their products vary significantly in quality and price. Unfortunately, higher price does not always correspond to higher quality. The reproducibility of the quality/properties of the same model electrode could vary, too. Therefore, the selection of the best manufacturer and electrode model for the available budget is an important one.

I have been looking unsuccessfully for a sources that provide objective information and compare electrodes from different manufacturers. If the forum members are willing to share their experience with different models and manufacturers, maybe we can build such a database that will help the labs to select the best quality and value electrodes.

Thank you in advance!

Bear in mind that all problems are problems of 3 spatial dimensions because we live in a 3D universe. But in some system geometries, due to symmetry or whatever, we can treat the wavefunction as separable and then only worry about 1 or 2 of those dimensions. As an example, long conjugated molecules are three-dimensional structures, so properly speaking we should treat them with three dimensional wavefunctions. But the long dimension is so distinct from the other two that we can approximate the system as one dimensional and worry only about a one-dimensional wavefunction to achieve some relatively good, although approximate, results for how an important subset of the electrons in that system behave. It happens that most of the properties of interest arise out of changes between states defined almost exclusively by wavefunctions along the long axis, so approximating the system as "one dimension" works really well here. We cannot do this in a spherical atom, however, in which all three dimensions have almost equal important by virtual of the system's geometry.

This kind of dimensional reduction is common in physics due to how much it can simply the math. We often go so far as to actually design experimental systems so that 1D mathematical treatments can be used. If we want to know heat transfer coefficients in a new material, for example, the common approach would be to fashion the material into a long, thin geometry like a wire or bar. This way, you can use the 1D heat equation, which has much easier solutions than its multidimensional counterpart. In fact, some multidimensional differential equations aren't even analytically solvable, so reducing the dimensionality of your experimental system may be your only way to get an exact value for parameters of interest.

My work is wanting me to make a method to look for a very specific nonpolar analyte at a PPB level. I've never made a method before and I am concerned that I won't have time to do everything I need to do by the deadline. I have looked through the internet to see if I can find a method detecting this analyte and I can't find it anywhere. Does anyone have any advice on how to move forward?

We use a Thermoscientific triplus 500 headspace, a Trace 1600 GC with a nonpolar column, and we have a triple quadripole  TSQ 9610 Mass Spec.

Hello,

I was just wondering whether the wavefunction ψ can take on any dimension? My textbook uses the Schrodinger Eq to derive solutions for a particle in a 1D box, but can it also yield solutions for higher dimensions?

Thanks!

Are we supposed to know what pressure the diver ordinarily breathes?

Yes. Think standard pressure and composition of air. This definitely counts as a common knowledge.

Plus what Hunter wrote - pressure in the tank is not what you are breathing while diving, air is delivered at the pressure consistent with the pressure at the depth the diver is at. 8 atm would mean around 70 meters.