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#1
Probe for EPMA / Re: Wish List for PFE Features
Last post by John Donovan - Today at 04:16:39 PM
Do you mean in the User Specified output?

I think it would make more sense to stay with Roman numerals to avoid confusion with the Siegbahn notation.
#2
Probe for EPMA / Re: Wish List for PFE Features
Last post by dawncruth - Today at 03:59:51 PM
Can we add Bragg orders to the export options. For example, export data for net intensities are given as Si ka (1,TAP) NECNT. Can we get something like Si ka1 (1, TAP), for the first order ka and Si ka3 for third order ka, etc.?

Thanks!
#3
Some thoughts about TMP's I've seen implemented in various instruments:

Some JEOL SEM's in the 90's used a Seiko mag-lev TMP. A bit sensitive to mechanical shock as the TMP's rotor could be knocked out of bounds and the TMP would crash. Crash, meaning the rotor magnetic suspension would turn off and the rotor would fall onto the emergency bearing. Very loud and screechy. Only a few such crashes could be tolerated before permanent damage was done. This TMP could handle total power losses, but only if the back up battery were charged and in good condition (not older than its reasonable useful lifetime). If you are bringing one of these back to life, you'll need to replace that battery (NiCd?). This TMP needed a battery for use in suspending the rotor during RPM rampdown after power loss. I'm not sure, but this TMP could have employed electromagnetic braking on power loss to reduce RPM rampdown time. The need for a battery in that era of Seiko TMP+ contro implies that they had not employed a rotor/motor power generation to power the suspension and centering magnets.

In our IonTOF instrument, a Leybold mag-lev TMP serves the main chamber that does employ rotor/motor power generation to power the suspension and centering magnets. So there is no battery to go bad. I've never caused this TMP to crash via mechanical shock, not for lack of unfortunate incidents! The mag-lev system has noiselessly brought the TMP to zero RPM after numerous power down events. The controller did go bad once, and Oerlikon-Leybold repaired it by replacing all of the aluminum capacitors. I should have thought of that!
#4
Alejandro's script above is very nice, but if you only want to just import the compositional data from your current Cameca or JEOL standard compositions (and any other available fields), you can simply utilize one of these two menus in the Standard application:



See also appendix A or B in the attached pdf.
#5
Few questions about turbo pumps maybe someone could answer it.

A) turbomolecular pump emergency braking.
Do anyone knows what happens with turbo pump at mains power loss? Agilent TP manuals tells this:
QuoteEmergency stop can be achieved by removing the power supply.
, which I think is equal to situation with mains power loss/blackout. More recent manuals also added disclaimer:
Quote...The use of this stop mode
could lead to faults and/or damages at the pump. ...
. The first sub-question is if that "emergency stop" is not the same as engaging "Stop" command?, where "stop" simply stops powering the motor and leaves it in inertial rotation state. If no air/gas at pump's vent port is applied, it would spin with very slow spindown for about 20-30 minutes until would fully stop on its own. Maybe disclaimer has in mind  the danger would come from other parts of vacuum system (i.e. probability of introducing atmosphere pressure by inoperable backing pump, as cutting of power rather of whole system (as EMO buttons do) and not just selectively of TP???). Or maybe pump is indeed stopped to halt in very short time, and thus danger comes from enormous strain introduced to blades due to fast, near instantaneous de-acceleration? Could such thing even be achieved at all? One of possible way I can think about would be shorting engine coils with high resistance, so TP would work at such event as generator with very huge load and would stall (that is not good not only for blades, but for coils or more precise both rotator and stator, where both would highly overheat (and rotator is practically impossible to cool).

B) electrical braking of TP
(Just to not confuse with emergency braking, at this point B it means a smooth slowing down of pump)
I looked through different manuals of TP, and none major vendors mentions such ability. I came across some hobbyist projects which implements such thing. There are some TPs on ebay (and similar) often either missing controllers, or being sold with damaged controller (i.e. cut wires and other atrocities). So naturally some hobbyist came up with own controller designs and some had implemented electric braking function.
    Meanwhile, all TP vendors have a unified way to slow down TP with introduction of small regulated air (or clean gas) stream at middle point of TP. For that all TPs have such vent port (inlet). Most of controllers has reserved pins for connection with valve connected to TP vent port, and controller then controls its operation, when "stop" command is being engaged, or if power is lost (where existence of emergency brakes hypothesized in point A by me are redundant).
    However, It gets interesting in official video from Agilent "Turbo Pump Care and Use 101 - Part 5 - Venting and Shutdown", at 3:29 there is a section "electric braking of the rotor" (https://www.youtube.com/watch?v=g33_NQsTMa0&t=209s). It is stated there that newest design has that mode. Actually I then dig deeper and found out that "newest" also include over 10 year Varian pumps, which ,honestly speaking, is not so "newest". It just seems this feature was never properly marketed and actually still is not. Even the most recent manuals and Datasheets of Agilent TwissTorr 305 has exactly 0 mentioning about that feature. It is cryptically described in integrated (small) controller manual (at RS232 communication protocol) and a bit more described (but also in very limited way) in the manual of rack-mountable controller. The feature can be completely overlooked if not knowing what to look for (it is called in controller manuals "Active Stop").
    I think it is very useful feature for SEM and EPMA, as there are situations where TP would be wished to be brought to halt (for safety), but without venting a chamber. I believe our Zeiss SEM use that function, as TP slowing down can be hear even if vent gas bottle is being closed at "vent chamber" command. Zeiss SEM also has feature of partial-vent which again, stops the TP, and keeps residual vacuum in the chamber (kind of energy efficient stand-by mode). As for EPMA-FEG, such mode would be useful for some of maintenance procedures, in example: swapping/doing maintenance of primary pump, doing maintenance of air compressor (all valves automatically closed, TP would loose backing vacuum), power saving during blackout (so UPS could keep UHV at gun for much much longer)...

  Had anyone hear anything about electric brakes of other vendor TP?
#6
JEOL / Re: Observation ON/OFF for sam...
Last post by sem-geologist - Today at 01:10:44 AM
Reading all that confusing terminology invented by JEOL, I can't help, but it reminds me knights who no more says "Ni" but "ekki ekki ekki ekki ptang zoom boing z'nourwringmm" from Monty Python's Holy Grail  ;D.  Why not use terminology of EHT (electron High tension), Isolation Valve, Heat Current, which are as clear as it can get clear.
#7
JEOL / Re: Observation ON/OFF for sam...
Last post by KerstinGruender - January 16, 2025, 07:08:43 PM
Hi, replying to myself and Anette - I had a look at what happens to the valves, and if I leave observation on and vent the exchange chamber, the beam 'retreats' into the top part of the column and a valve closes, but the beam itself stays on. This valve automatically re-opens during evac after the sample change. Not sure at what stage it is triggered and why, maybe related to the vacuum. Turning observation off turns the beam totally off (no more beam in the sketch in the observatioon tab). So may be a different setup to what you're referring to, Anette, and potentially the beam is protected automatically. In any case, I'm continuously learning about the instrument. Something new every week :)
Kerstin
#8
JEOL / Re: Observation ON/OFF for sam...
Last post by KerstinGruender - January 16, 2025, 05:20:21 PM
Thank you, Anette!  :)

Makes sense that vacuum fluctuations will be worse for the filament life. I'm not really fond of changing the filament more frequently than I'd need to ;) Six months is pretty good!
I wonder if it may also depend on how good your vacucum is to start with/how much it will fluctuate. Perhaps this is why diffeent people who have worked on different probes/labs remember different things. I'll quiz the JEOL engineer about it too, next time they come.
I'll continue to turn observation off/on for now and will see what works best for us with the saturation. Our probe is running almost 24/7 anyway, so not much time to even think about standby.

How, and how often, did you monitor the filament saturation? Run an auto saturation to see whether the code has changed - like every week, or more/less frequently?

Cheers,
Kerstin
#9
Probe for EPMA / Re: Trying to combine selected...
Last post by John Donovan - January 16, 2025, 09:58:20 AM
Just a quick note to point out the two ways one can combine samples run under different conditions with different elements in the Probe for EPMA Analyze! window.

The Combine Samples feature can be performed two different ways:



Either way you can combine either elements (or data lines) for various purposes. In the following example Scott Boroughs acquired some elements at 15 keV (using TDI to correct for beam sensitivity) and some elements at 25 keV (again using TDI) including Br Ka.

Combining them using either method yields this output (note the different keVs):

Un   92 (Un   60  10Br, Un   88  10Br)
(Magnification (analytical) = 300000),        Beam Mode = Analog  Spot
(Magnification (default) =      100, Magnification (imaging) =    100)
Image Shift (X,Y):                                         .00,    .00

Formula Based on Sum of Cations = .000   Oxygen Calc. by Stoichiometry
Number of Data Lines:  20             Number of 'Good' Data Lines:  20
First/Last Date-Time: 12/12/2024 02:11:46 PM to 12/12/2024 02:53:45 PM
WARNING- Using Time Dependent Intensity (TDI) Element Correction

Average Total Oxygen:       43.860     Average Total Weight%:   96.454
Average Calculated Oxygen:  43.860     Average Atomic Number:   11.352
Average Excess Oxygen:        .000     Average Atomic Weight:   20.442
Oxygen Equiv. from Halogen:   .173  Halogen Corrected Oxygen:   43.686
Average ZAF Iteration:        3.00     Average Quant Iterate:     5.00

Oxygen Calculated by Cation Stoichiometry and Included in the Matrix Correction
Oxygen Equivalent from Halogens (F/Cl/Br/I), was not Subtracted in the Matrix Correction (because oxygen from halogens was greater than zero)
WARNING- Duplicate analyzed elements are present in the sample matrix!!
Use Aggregate Intensity option or Disable Quant feature for accurate matrix correction.

Combined Analytical Condition Arrays:
ELEM:       Na      Ca       S       U       B      Al      Br      Si      Th       S
CONDN:       1       1       1       1       1       1       1       1       1       1
CONDO:       1       1       1       1       1       1       1       1       1       1
KILO:     15.0    15.0    15.0    15.0    15.0    25.0    25.0    25.0    25.0    25.0
CURR:     12.0    12.0    12.0    12.0    12.0    10.0    10.0    10.0    10.0    10.0
SIZE:     12.0    12.0    12.0    12.0    12.0    12.0    12.0    12.0    12.0    12.0

Un   92 (Un   60  10Br, Un   88  10Br), Results in Elemental Weight Percents
 
ELEM:       Na      Ca       S       U       B      Al      Br      Si      Th       S       O
TYPE:     ANAL    ANAL    ANAL    ANAL    ANAL    ANAL    ANAL    ANAL    ANAL    ANAL    CALC
BGDS:      MAN     MAN     MAN     MAN     LIN     MAN     MAN     MAN     MAN     MAN
TIME:    50.00   50.00   50.00   50.00   40.00   40.00   40.00   40.00   40.00   40.00     ---
BEAM:    12.07   12.07   12.07   12.07   12.07    9.92    9.92    9.92    9.92    9.92     ---

ELEM:       Na      Ca       S       U       B      Al      Br      Si      Th       S       O   SUM 
XRAY:     (ka)    (ka)    (ka)    (ma)    (ka)    (ka)    (ka)    (ka)    (ma)    (ka)      ()
  2079  13.280   5.456    .056   -.021   1.466   5.457   1.613  25.022   -.013    .066  43.594  95.976
  2080  13.125   5.512    .056   -.007   2.028   5.395   1.793  25.223   -.003    .059  44.978  98.160
  2081  13.174   5.279    .064   -.024   1.312   5.398   1.707  25.210   -.014    .064  43.315  95.486
  2082  13.040   5.429    .057   -.025   1.274   5.443   1.796  25.113   -.013    .058  43.156  95.329
  2083  13.406   5.342    .062    .000   1.687   5.401   1.687  25.077    .009    .064  44.108  96.843
  2084  13.320   5.178    .059   -.023   1.692   5.438   1.718  25.132   -.003    .072  44.122  96.704
  2085  13.306   5.343    .059   -.017   1.339   5.449   1.751  25.283   -.026    .078  43.588  96.152
  2086  13.152   5.400    .063   -.004   1.539   5.413   1.727  24.909   -.003    .049  43.511  95.755
  2087  13.363   5.232    .059   -.010   1.370   5.405   1.829  25.207   -.008    .067  43.493  96.007
  2088  13.363   5.389    .062    .010   1.484   5.446   1.723  25.086   -.010    .074  43.725  96.352
  2089  13.393   5.365    .062   -.002   1.616   5.485   1.729  25.119   -.014    .057  44.065  96.876
  2090  13.415   5.260    .057   -.012   1.570   5.468   1.726  25.027   -.004    .074  43.825  96.406
  2091  13.295   5.477    .049   -.016   1.491   5.441   1.730  25.173   -.002    .062  43.808  96.508
  2092  13.438   5.538    .063   -.043   1.750   5.475   1.654  25.087   -.003    .082  44.436  97.477
  2093  13.218   5.347    .061   -.019   1.310   5.480   1.627  25.200   -.009    .069  43.420  95.705
  2094  13.321   5.324    .056   -.001   1.576   5.436   1.792  25.063   -.028    .062  43.823  96.425
  2095  13.563   5.411    .059   -.015   1.662   5.476   1.768  24.963   -.004    .066  44.066  97.016
  2096  13.126   5.227    .057   -.001   1.702   5.403   1.734  25.097    .002    .073  44.027  96.446
  2097  13.258   5.348    .056    .007   1.829   5.441   1.755  25.101   -.021    .074  44.442  97.290
  2098  13.319   5.250    .064   -.037   1.540   5.452   1.793  25.015   -.001    .071  43.697  96.164

AVER:   13.294   5.355    .059   -.013   1.562   5.440   1.733  25.105   -.008    .067  43.860  96.454
SDEV:     .127    .099    .004    .014    .193    .029    .057    .093    .009    .008    .435    .697
SERR:     .028    .022    .001    .003    .043    .007    .013    .021    .002    .002    .097
%RSD:      .95    1.84    6.03 -103.97   12.34     .54    3.27     .37 -110.91   11.96     .99
STDS:      104      17      17    4001      43      48    7000      48     150      17     ---

STKF:    .3213   .2702   .2216   .8671   .4010   .0236   .6301   .1232   .9072   .2090     ---
STCT:   4130.0   507.0  6480.7  3089.1  1627.6  1219.3  5055.2  3686.3  5079.2  2226.0     ---

UNKF:    .0776   .0489   .0005  -.0001   .0013   .0304   .0135   .1541  -.0001   .0004     ---
UNCT:    997.5    91.7    13.7     -.3     5.2  1574.0   108.5  4608.8     -.4     4.4     ---
UNBG:      4.5     1.2     8.9     6.3     3.6    22.1    40.4     7.3     8.8     2.7     ---

ZCOR:   1.7134  1.0960  1.2587  1.3472 12.1592  1.7891  1.2807  1.6296  1.0996  1.6065     ---
KRAW:    .2415   .1808   .0021  -.0001   .0032  1.2908   .0215  1.2502  -.0001   .0020     ---
PKBG:   223.84   74.98    2.54     .95    2.50   72.09    3.68  634.63     .95    2.64     ---

TDI%:    5.440    .000    .000    .000    .000    .000    .000  -2.139    .000    .000     ---
DEV%:       .2      .0      .0      .0      .0      .0      .0      .1      .0      .0     ---
TDIF:  LOG-LIN    ----    ----    ----    ----    ----    ---- LOG-LIN    ----    ----     ---
TDIT:    59.75     .00     .00     .00     .00     .00     .00   48.60     .00     .00     ---
TDII:    1002.    ----    ----    ----    ----    ----    ----   4612.    ----    ----     ---
TDIL:     6.91    ----    ----    ----    ----    ----    ----    8.44    ----    ----     ---

Note that we did fix a minor bug that was preventing analysis of combined standard samples, but this is fixed in the latest Probe for EPMA update. Update as usual from the PFE Help menu.

The advantage of this method is that one can acquire all their samples with some elements at one keV, and then acquire different elements at a different keV (or beam current, say for trace elements) and then combine them later.

This method also allows one to acquire TDI intensities on multiple elements on the same spectrometer!
#10
EPMA Standard Materials / Re: SPI Microanalytical Standa...
Last post by Dan R - January 16, 2025, 08:32:53 AM
Thanks, Rob -- is this your website?
https://micro-analysis.com/standards
?