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--- weight_percentage_in_original [2022/01/21 02:54] – rowlesmr3
+++ weight_percentage_in_original [2022/11/03 15:08] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
+====== Calculating the weight percentages in the original specimen when using an internal standard  ======
+When quantifying specimens with an internal standard, TOPAS provides the keywords ''spiked_phase_measured_weight_percent'', ''corrected_weight_percent'', and ''weight_percent_amorphous'' to set the amount of spike phase added, to get the corrected weight percentage of a phase, and to get the total amorphous amount in the specimen. These values refer to the specimen _with_ the standard in it. You often need the values referring to the original specimen, that is, without the standard.
+The following macros calculate those values for you. Furthermore, the macros also allow for the addition of a standard that itself has a (known) amorphous fraction; the calculation of the amorphous fraction in the original sample takes this additional amorphous fraction into account.
+===== To use the macros =====
+These macros should work in TOPAS version 5-7.
+**The str which is the standard must be the first str to appear in the xdd**
+Potential usages:
+The first example has a sample containing 25 wt% standard, that is itself 100% crystalline. The following "0" is a placeholder for the amorphous weight percentage, which will appear after refinement.
+All non-spike phases have the Original_WP macro. After refinement, the values will be updated with their weight percentages in the the original sample.
+<code topas>
+xdd
+   str 'This is the first str. It must the standard str.'
+      Spike_amount_in_specimen(25, 0)
+   str
+      Original_WP(0)
+   str
+      Original_WP(0)
+   str
+      Original_WP(0)
+</code>
+The second example has a sample containing 50 wt% standard, which is itself 90% crystalline. That is, equal weights of standard and sample were mixed together. The analysed specimen contains 5 wt% amorphous material from the standard, in addition to any already present in the sample.
+<code topas>
+xdd
+   str 'This is the first str. It must the standard str.'
+      Spike_amount_in_specimen(50,90, 0)
+   str
+      Original_WP(0)
+   str
+      Original_WP(0)
+   str
+      Original_WP(0)
+</code>
+===== The macros =====
+<code topas>
+macro Spike_amount_in_specimen(& std_wt_pct, amor) 'this goes in the spike phase str'
+{
+	'The spike phase str must be the first str in the xdd. This is because of how move_to works'
+	Spike_amount_in_specimen(std_wt_pct, 100, amor)
+}
+macro Spike_amount_in_specimen(& std_wt_pct, & std_cryst, amor) 'or this goes in the spike phase str'
+{
+	'The spike phase str must be the first str in the xdd. This is because of how move_to works'
+	move_to xdd
+		local !whole_specimen_total_std_addition_ = std_wt_pct;
+		local !whole_specimen_cryst_std_addition_ = std_cryst whole_specimen_total_std_addition_ / 100;
+		local !original_sample_amorphous_  100 : amor
+	move_to str
+		spiked_phase_measured_weight_percent = whole_specimen_cryst_std_addition_ ;
+}
+macro Original_WP(result) 'this goes in every non-spike str in the xdd'
+{
+	local orig_wt_ = 100 Get(corrected_weight_percent) / (100 - whole_specimen_total_std_addition_); :  result
+	existing_prm original_sample_amorphous_ -= orig_wt_;
+}
+</code>