Study on the Equivalence of Metallic-Cerium-Simulated Uranium-Aerosol Generation under Fire
, Ming Guo 1,*, Biao Li 1, Fei Wu 1, Jie Tian 1 and Desheng Ma 1Round 1
Reviewer 1 Report
l There are statements attributed to other work which is not cited. For example, authors have to show the reference after “in literature” in line 179 and in the caption of Fig.4. Authors should check the whole manuscript.
l The captions of figures and tables should be more informative. For example, “Fig. 6 combustion products XRD analysis” is poor in grammar. “Table 6. Particle size distribution data” of what? Authors should carefully check all captions.
l Table 7: It seems curious that the minus content of Zn in this table. What does this minus value mean?
l What is “MMAD” in line 283?
l Authors should describe “Conclusion” of “concluding remarks” in Page 10, based on results and discussion.
l The reference list is not completed. Please follow the instruction of the journal.
Author Response
Response to Reviewer 1 Comments
Point 1: There are statements attributed to other work which is not cited. For example, authors have to show the reference after “in literature” in line 179 and in the caption of Fig.4. Authors should check the whole manuscript.
Response 1: References have been marked in the manuscript and in the title of Figure 4. And we have checked the whole manuscript.
Point 2: The captions of figures and tables should be more informative. For example, “Fig. 6 combustion products XRD analysis” is poor in grammar. “Table 6. Particle size distribution data” of what? Authors should carefully check all captions.
Response 2: We have added more details to the captions of Figure 6 and Table 6. The other captions in the paper were also checked.
Point 3: It seems curious that the minus content of Zn in this table. What does this minus value mean?
Response 3: Since the experiments on metallic zinc were conducted before this experiment, trace amounts of zinc may be present inside the experimental apparatus. Therefore, the elemental zinc was also analyzed during the semi-quantitative analysis. The minus values of zinc indicate that the residual zinc inside the experimental apparatus is very small, difficult to detect, and negligible.
Point 4: What is “MMAD” in line 283?
Response 4: “MMAD” is Mass Median Aerodynamic Diameter.
Point 5: Authors should describe “Conclusion” of “concluding remarks” in Page 10, based on results and discussion.
Response 5: We have added a description of the concluding section of the manuscript.
Point 6: Line 121: The reference list is not completed. Please follow the instruction of the journal.
Response 6: We have completed the reference list as required by the journal.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The topic is relevant. The English language must be thoroughly revised - in most cases I was able to understand and sugegsted modifications (file attached, see comments on pdf), but for a few sentences the meaning is obscure. Also revise with an online corrector, such as Grammarly or similar.
Add interpretation of Oxide presence in Figure 2A (visual).
2.4.3: I understand the difficulties encountered - but this is history - it is true that we learn more from errors than from success. The relvant outcome, however, is that you were able to solve this problem using a more sensitive detector. Only this should be recorded here.
Figure 4: you are representing points as dots. indeed each measurement involves uncertainty both on the x and y axes - if possible you should add uncertainty bars.
Page 6 lines 180-183: I am not an expert but I would definitely like some discussion about the stability of very fine aerosols. From my knowledge, when you get close to the size of molecules, aerosols become very unstable. I require some comment if possible.
Figure 4b: When considering cumulative mass fractions, it is clear that errors for large particles have a very strong influence. This is linked to my previous comment about the possibility of providing uncertainty evaluations (as is usual in experiments). It may be true that the errors are probably smaller when considering 10 micron rather than 0,1 or 1 - but it is exactly this that should be argomented.
Page 9 line 261: is this the reason...? I WOULD HAVE SUSPECTED THAT A KIND OF COHALESCENCE IS PRESENT - which is quite common with aerosols....
Page 9 line 273: ...so you agree: there was cohalescence - aggregation or adsorption. And with larger air flow you have droplet breakdown and collapse, generating finer particles......... in liquid combustion studies there is considerable published work about droplet breakdown, aggregation, etc.
Page 10 lines 308-312 (conclusions): ... from the discussion, it appears that you feel that there is no direct evidence of the suitability of using Cerium instead of Uranium - that is, that you did not have success.
This is in general not a positive result - even if experience can be valuable.
Comments for author File: Comments.pdf
Author Response
Response to Reviewer 2 Comments
Point 1: The topic is relevant. The English language must be thoroughly revised - in most cases I was able to understand and sugegsted modifications (file attached, see comments on pdf), but for a few sentences the meaning is obscure. Also revise with an online corrector, such as Grammarly or similar.
Response 1: We have used the DeepL software to correct the grammar of the manuscript.
Point 2: Add interpretation of Oxide presence in Figure 2A (visual).
Response 2: The surface of the cerium metal gradually darkens in the high temperature flame. It shows that the surface of cerium metal reacts with oxygen at high temperature to form a black oxide.
Point 3: 1.4.3: I understand the difficulties encountered - but this is history - it is true that we learn more from errors than from success. The relvant outcome, however, is that you were able to solve this problem using a more sensitive detector. Only this should be recorded here.
Response 3: We removed the part of the method of failure measurement that was used in the 1.4.3. Only the successful methods were retained.
Point 4: Figure 4: you are representing points as dots. indeed each measurement involves uncertainty both on the x and y axes - if possible you should add uncertainty bars.
Response 4: Since there are many lines in Figure 4, adding uncertainty bars will make Figure 4 look more confusing.
Point 5: Page 6 lines 180-183: I am not an expert but I would definitely like some discussion about the stability of very fine aerosols. From my knowledge, when you get close to the size of molecules, aerosols become very unstable. I require some comment if possible.
Response 5: When the aerosol particle size is close to the molecular level, the aerosol particles are mainly influenced by Brownian motion. The fine aerosol particles tend to condense into larger aerosol particles when they touch each other. Since the scale of aerosol particles studied in this paper is much larger than the molecular scale, the stability of fine aerosol particles is not investigated.
Point 6: Figure 4b: When considering cumulative mass fractions, it is clear that errors for large particles have a very strong influence. This is linked to my previous comment about the possibility of providing uncertainty evaluations (as is usual in experiments). It may be true that the errors are probably smaller when considering 10 micron rather than 0,1 or 1 - but it is exactly this that should be argomented.
Response 6: This is indeed the case. Aerosol particles have better stability in the larger particle size range. As can be seen in Figure 4b, the aerosol particle size distribution varies significantly at smaller scales, while it exhibits very similar trends at larger scales.
Point 7: Page 9 line 261: is this the reason...? I WOULD HAVE SUSPECTED THAT A KIND OF COHALESCENCE IS PRESENT - which is quite common with aerosols....
Response 7: There was no evidence that the presence of a particular cohalescence influenced the experimental results. Since only cerium is measured in this paper, the presence of cohalescence will not affect the experimental results.
Point 8: Page 9 line 273: ...so you agree: there was cohalescence - aggregation or adsorption. And with larger air flow you have droplet breakdown and collapse, generating finer particles......... in liquid combustion studies there is considerable published work about droplet breakdown, aggregation, etc.
Response 8: The aerosol particles in this paper are not liquid droplets, but metal oxide solid particles, and therefore cannot be simply explained by the liquid combustion theory.
Point 9: Page 10 lines 308-312 (conclusions): ... from the discussion, it appears that you feel that there is no direct evidence of the suitability of using Cerium instead of Uranium - that is, that you did not have success. This is in general not a positive result - even if experience can be valuable.
Response 9: According to the experimental results, the effect of cerium instead of uranium to simulate the particle size distribution is not very good, but the effect of cerium instead of uranium to simulate RF is better.
