Improving a PGNAA Technique to Detect Heavy Metals in Solid Samples
Round 1
Reviewer 1 Report
The manuscript Improving the detection of heavy elements in soil samples using a PGNAA technique describes the PGNAA technique used for the determination of the concentrations of Cr, Ti and Zn. The topic is not specifically novel but it is within the aims and scope of the journal. The submitted manuscript needs major revision to be suitable for publishing in the Applied Sciences. In this form, I do not suggest it for publication.
Some specific details/comments are given in the following text:
The abstract should be rewritten with details about the novelty of this study.
The Introduction should be improved with revised aims (the authors should pinpoint what is the novelty of this study in the aims).
The discussion is lack and does not have the significant scientific references. It should be improved.
Generally, in this form, the manuscript does not represent novel and scientifically significant research for publishing.
Author Response
Please see the attached file
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The manuscript is devoted to the modifying the methodology for determining the concentrations of certain metals in soil samples using prompt gamma-ray neutron activation analysis.
The abstract needs to be improved by expanding the description of the results obtained. It is also important to note why Cr, Ti, and Zn were studied rather than other metals. What is the fundamental novelty of the proposed improvement of the analysis method?
Keywords: keywords should not repeat the words from the title.
- Introduction.
More attention needs to be paid to examples of PGNAA applications for the analysis of the chemical composition of environmental samples. For instance, nothing is said about the possibility of using this method for the analysis of metal concentrations in bottom sediments. It is helpful to briefly reflect the breadth of application of the method for completely different objects (second paragraph of the introduction).
TNC, BGO should be deciphered at the first mention - what do these abbreviations stand for?
Figure 1: Please indicate in the caption which lines of the spectrum refer to which case. For example, instead of “background with a moderator before the detector”, it is useful to specify “background with a moderator before the detector (BkGd-Mod)”, etc. (if I correctly matched the caption and legend of the figure).
- Experimental.
DD reaction – please explain what DD means.
2.2. Sample preparation.
It is not clear by what method the metal concentrations were determined (four values for each metal). What were the concentrations of metals in soils before the introduction of additional masses of metals? What soils have been studied (give a brief description of them, at least what type they belong to, whether the content of organic matter is high, what is the grain size distribution, etc.).
- Results and Discussions
MDC – please decipher.
Fig. 5: Why is the spectrum of pure Zn not shown (as the spectra of pure Cr and Ti are shown in Fig. 3 and Fig. 4)?
“where ?, ?, and ? are related to the net counts P, element's concentration in (wt.%), and the
associated background counts; respectively.” – which letter indicates the concentration (C or P)?
Fig. 6-8: On fig. 6 shows the number of neutrons (in MeV), and in fig. 7 and 8 are not specified. The solid line in fig. 6 was carried out using Monte Carlo simulations, and in fig. 7 and 8, it was carried out using a different method. It is necessary to bring the captions to these three figures to a single format and draw an approximation line using the same method, otherwise it is difficult to compare.
The results of the experiment showed that “For Cr, the detection limit of 0.85 ± 0.26 wt % shows a slight improvement by 6.0 %, while our results for Ti (0.69 ± 0.19) wt % and Zn (1.53 ± 0.47) wt % show a downgrade by 23% and 38%, respectively”, that is, only for Cr it was possible to achieve a lower detection limit, while for Ti and Zn the results were less successful. Therefore, doubts arise about: (1) the correctness of the title of the paper (“Improving the detection of heavy elements” is not demonstrated in the manuscript); (2) the practical significance of the results obtained - for what purposes the modified method proposed by the authors may be useful. This requires more detailed discussion in the manuscript.
The list of references must be made according to the Journal’s requirements.
The manuscript must be made according to the Journal’s requirements.
Thus, the manuscript requires major revisions.
Author Response
Please see the attached file.
Author Response File: Author Response.pdf
Reviewer 3 Report
Toxic metal remediation is one of important issues in environmental study. It is interesting and useful that the authors have evaluated a method for prompt gamma-ray neutron activation analysis (PGNAA) to detect heavy elements in soil samples. In total, the MS was written sound. Hence, it is recommended to be published after some revisions.
- It is better to have a sub-section of calculation and statistical analysis for data in M&M section.
- It is better to change from present tense form to past tense form in the MS, such as “are being”; “are shown”; “are presented” changed to “were xxx”.
Author Response
Please see the attached file.
Author Response File: Author Response.pdf
Reviewer 4 Report
Dear Editors and Authors,
I have carefully read your manuscript entitled "Improving the detection of heavy elements in soil samples using a PGNAA technique". The problem of soil contamination with heavy metals and the need to monitor their content in the soil has been known for many years and (unfortunately) still very relevant today. I suggest a minor revision of the paper. Below I am presenting my comments:
- keywords should differ than words in the title;
- please add an introductory sentence at the beginning of your abstract. Why is this technique worth to paying attention?
- in my opinion, in the Introduction section, one paragraph about heavy metals pollution could be added to show how significant is the problem.
- please add the full name of chemical elements when you first time write symbols
- in my version of the manuscript, the quality of figures 2 and 3 is poor. Can you check it?
- please add 2-3 more of the newest literature citation (one paper from 2022, no papers from 2021, two from 2020). The potential reader must be sure that the described results are new and that no one has published such reports so far.
- please, remove citations from the conclusion section, it should be your own thoughts, additionally please indicate clearly the novelty statement resulting from this manuscript
Best regrds
Author Response
Please see the attached file.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
I strongly respect that the authors made an effort to improve the manuscript. After the check of the changes the authors made I do not feel that the manuscript was significantly improved (I do not suggest it for publication in Applied science). Anyhow, I suggest the editor to make the decision based on the all revisions.
Author Response
Reviewer comment: I strongly respect that the authors made an effort to improve the manuscript. After the check of the changes the authors made I do not feel that the manuscript was significantly improved (I do not suggest it for publication in Applied science). Anyhow, I suggest the editor to make the decision based on the all revisions.
Our answer: We really appreciate the time and effort the reviewer spent in reading the manuscript not only once but twice. His/her decision is highly respected, but we did not get specific comments from him/her that helped us modifying the mansuscript in order to accomodate the criteria for acceptance.
The novility of the work focused on improving the signal-to-noise ratio in the detector in order to exctract information from overlapping gamm-ray peaks, mainly peaks from the activation of the detector elements with those from the elements in the sample. New optimization of the PGNAA setup was performed, and the achievements were proved by measuring the MDC of Ti, Zn and Cr in soil samples. Their gamma-rays following fast neutron reaction were being built on strong peaks from the detector. The results we found are in almost perfect agreements with the reported data, which had more clean setup and greater neutron fluxes. Other significant achievements were: Reducing the size of the sample from 2.0 kg to 650 g, and irradiation time from 4000 s to 2000 s.
Reviewer 2 Report
The authors fully responded to my comments and made the required corrections to the text. Therefore, the manuscript can be accepted for publication in its current form.
Author Response
Viewer Comment: The authors fully responded to my comments and made the required corrections to the text. Therefore, the manuscript can be accepted for publication in its current form.
We thank the reviewer for his time in evaluating our manuscript. We really appreciate his comments that helped us improving the whole text and the figures. We wish him/her the best.
