Review Reports - Features of Generation, Propagation and Application of Special Ultrasonic Impulses in Viscous Liquids

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Comments

The study titled “Features of a Generation, Propagation, and Application of Special Ultrasonic Impulses in Viscous Liquids” aimed to evaluate the efficiency of using ultrasonic pulses compared to continuous ultrasound radiation, particularly in scenarios where there is a significant distance between the emitter and the reaction zone. A notable contribution of the study is its exploration of the ability to regulate pressure drops and the speed of the acoustic signal, which holds promising implications for special force effects and information transmission.

However, before the article can be considered for acceptance and publication, some adjustments and additional details are necessary to enhance its clarity and overall quality. In particular, certain sections would greatly benefit from more comprehensive descriptions, especially in the presentation of the study results, as this would strengthen the manuscript's overall argument. With these revisions, the paper has the potential to make a valuable contribution to the field.

General Comments

I would kindly ask you to consider the following text and provide your perspective on what novel contributions your study presents in relation to it:

“During the 20 to 30 last years, a special attention has been devoted to the modelling of the ultrasonic wave propagation in viscous media. In almost these models, the phenomenon of propagation is represented by a slightly dispersive linear system for which the phase is a linear function of frequency (Hertz & Al, 1991). Unfortunately the response of such systems is not causal (D.T, 1995). Hilbert transform or Fractional Calculus are some of the main mathematical tools which have been used to develop theoretical models respecting causality (Hertz & Al, 1991) (D.T, 1969) (He, 1999). In the case of viscous media for which the attenuation of the waves is proportional to the frequency squared, the methods based on Laplace transform allow the derivation of impulse responses respecting the causality (Thomas.L, 1995) (D.T, 1969) (Norton & Purrington, 2009)”.

Your insights would be greatly appreciated to clarify how your research builds upon or differentiates from the aspects highlighted in this excerpt.

Oudina Assia and Djelouah Hakim. “Propagation of Ultrasonic Waves in Viscous Fluids”.Wave Propagation in Materials for Modern Applications. Andrey Petrin (Ed.), ISBN: 978-953-7619-65-7, InTech, 2010.

https://cdn.intechopen.com/pdfs/6473/InTech-Propagation_of_ultrasonic_waves_in_viscous_fluids.pdf

Conducting academic research requires a thorough review of the current state of the research field. This process not only facilitates a comprehensive understanding of the subject but also highlights gaps and opportunities for further investigation. To achieve this, it is crucial to carefully select and cite key publications, as they offer valuable insights and provide the foundational framework for building new findings. Neglecting this step may result in a lack of contextual relevance or the inadvertent omission of significant contributions from prior studies. Therefore, a meticulous literature review is an essential component of producing high-quality and impactful research. From this perspective, I kindly suggest adding a paragraph to the introduction that addresses the aforementioned aspects.

It would be highly advantageous for the article to adopt the structure recommended in the journal's Instructions for Authors: Introduction, Materials and Methods, Results, Discussion, and Conclusions (optional). In the current study, the Materials and Methods, Results, and Discussion sections were merged into a single section. Additionally, the discussion was relatively superficial, focusing exclusively on the results of this study. The journal's Instructions for Authors emphasize that researchers should analyze their findings and interpret them in the context of prior studies and the proposed hypotheses. The discussion should explore the broader implications of the results while addressing the study's limitations. Suggestions for future research directions may also be included.

The abstract is dense, and some sentences are overly complex, making it difficult to follow the main ideas. Simplifying and breaking down sentences could enhance readability. The abstract should consist of a single paragraph and follow a structured format, without the use of headings. It should include the following elements: 1) Background: Introduce the research question within a broader context and clearly state the purpose of the study; 2) Methods: Provide a concise description of the primary methods or procedures employed, mentioning any relevant preregistration details, as well as species and strains if animals were involved; 3) Results: Present the key findings of the research succinctly; and 4) Conclusion: Highlight the main conclusions or interpretations derived from the study.

Specific Comments

The following list shows my comments for individual sections:

A. Abstract

1. Statements such as "unique conditions for a special force effect or information transmission" and "a possible way to a new technology" are vague and lack specificity. More concrete descriptions or examples would make the claims more compelling.

2. While the text mentions the development of "unique conditions" and "a possible way to a new technology," it does not clearly highlight what makes this work novel or superior compared to existing approaches. Explicitly stating the innovation would strengthen the summary.

3. Although applications like "metal dissolution" and "mass transfer" are mentioned, their relevance to the described technology is not clearly explained. Connecting the described waves more explicitly to these applications would improve the reader's understanding of the practical significance.

4. Phrases like "far away treatment of different objects" and "fine peculiarities of providing the necessary properties" are awkward or non-standard in English. Refining the phrasing would make the text sound more polished.

5. The abstract lacks specific data, findings, or evidence supporting the claims made. Including even brief quantitative or qualitative results would lend more credibility to the work.

A. Introduction

1. Page 1, lines 23-25. I believe the author should consider citing only studies that utilized ultrasound.

2. Lines 33-37. Has the influence of the acoustic signal structure on process intensification and the effectiveness of ultrasound stimulation been extensively studied in the literature? Given the emphasis on the importance of selecting the appropriate type of ultrasound exposure to maximize productivity, it would be valuable to know if there are comprehensive studies addressing these aspects.

3. Page 2, lines 67-69. I believe this type of sentence would be more appropriate for the discussion or conclusion section of the study.

B. Section 2

1. Equation 1. Does the first parameter in this equation refer to density? Shouldn't it be represented by the Greek letter "rho"?

2. Equation 1. “ηΔv”. Could the author kindly verify whether this expression is correct?

3. Page 3. “calculations given in the papers [21,24]”. References 21 and 24 are books.

4. It is important for the author to describe all the parameters used in Equations 4 and 5. Additionally, could the author clarify what "c" represents?

5. It is important for the author to describe all the parameters used in Equations 6 and 7.

6. “the ratio div{∂φ/∂z Grad φ} = ∂φ/∂z Δφ + 0.5 ∂z (Grad φ)²”. Could the author please check if anything is missing here?

7. Page 4, lines 151-156. The author could include a reference to support this sentence.

8. Page 5, lines 184-186. The reader might question the differences between the present study and those cited by the author. It would be helpful to clarify this in the discussion section.

9. It is important for the author to describe all the parameters used in Equations 14, 15, 16 and 17.

10. Figure 1. The text refers to figures 1a and 1b, but the authors did not label these figures with the letters “a” and “b”.

11. Page 6, lines 208-209. It is highly important for the author to specify the software used to perform the simulations and numerical analysis of the data.

12. Page 7, Figure 2. It is highly important for the author to specify the units of measurement in Figure 2 and its caption.

C. Section 3

1. Page 7, lines 245-248. Kindly consider including a reference to support this sentence.

2. Page 9. It is important for the author to describe all the parameters used in Equation 23.

3. Page 11, Figure 4. This figure should be revised as it contains overlapping information. Additionally, it is important for the author to provide more details about the figure in the text. For instance, what do "27.11" and "H, 1, 1" represent? Do the gray columns indicate identical values?

D. Conclusion

1. Page 11. “The possibility of modifying the shape of nonlinear ultrasound pulses, substantiated in this work, seems to be a promising tool not only for a more noticeable intensification of a number of processes in comparison with traditional irradiation, but also for obtaining good results in cases where the use of conventional ultrasound is ineffective. In particular, the irradiation of large volumes of dissipative liquids with suspended solids particles is met with the problem of reducing the efficiency of intensification in areas far from the source of the ultrasonic unit due to the exponentially rapid absorption of acoustic energy”. I firmly believe that the author could enhance the study by conducting computational simulations to more accurately explore the comparative efficiency of continuous and pulsed ultrasound radiation in intensifying processes such as dissolution, extraction, and dispersion of metal compounds. The results currently presented do not provide sufficient evidence for the reader to draw this conclusion.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The article addresses the comparative effectiveness of using pulsed and continuous ultrasound in enhancing various chemical processes, such as metal dissolution, solvent extraction, and mass transfer through immiscible liquid interfaces. The author proposes a theoretical approach to compare the effectiveness of the two types of ultrasound irradiation using mathematical models and efficiency coefficients (H) for different applications. The study also presents results on the industrial applications of pulsed ultrasound, particularly in dissipative liquids and complex media.

The use of ultrasound in chemical processes is an important research area, and the pulsed approach could offer interesting solutions for optimizing these processes. The article is well-structured in terms of theory, using mathematical models to demonstrate the advantages of pulsed ultrasound in industrial applications The discussion on the benefits of pulsed ultrasound for processes such as metal dissolution, solvent extraction, and mass transfer in immiscible liquids is highly relevant, particularly for the chemical and industrial sectors

While the introduction clearly presents the study's objectives, it would benefit from a more detailed literature review on previous works addressing the impact of pulsed versus continuous ultrasound in similar processes. This would provide more context for the study and highlight the novelty of the proposed method.

Some technical terms, such as the attenuation coefficient $κd\kappa_d$ , are introduced without detailed explanations. A clarification or a reference to a preliminary theoretical section could be helpful for non-specialist readers.

The section presenting the results and their discussion could be expanded. It would be beneficial to explain more thoroughly the practical implications of the obtained results, particularly in the industrial context, and to add specific examples of applications.

Although the article presents theoretical relationships, it would be essential to include more experimental data to validate the theoretical results. This would strengthen the credibility of the models and show the real-world applicability of the findings. Figures comparing theoretical results with actual measurements would be very useful.

The metal dissolution model (Equation 25) could be further detailed. For example, the effects of metal size, acid concentration, and other variables could be explored more deeply to better understand the interactions between ultrasound and dissolution.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Comments

As noted in the previous review, the work is interesting and has potential; however, certain aspects require improvement before it can be considered suitable for publication.

General Comments

In the previous review, I included a transcript of an excerpt from the study conducted by Assia and Hakim (2010), which represents the state of the art in this area of research. The authors could have adopted a similar approach to clearly highlight the research gap they intended to address. However, only a single excerpt related to the reference I provided was included.

In light of this, I transcribe below the same text used in the previous review:

Conducting academic research necessitates a thorough review of the current state of the research field. This process not only fosters a comprehensive understanding of the subject but also identifies gaps and opportunities for further exploration. To achieve this, it is essential to carefully select and cite key publications, as they provide valuable insights and form the foundational framework for building new findings. Overlooking this step can lead to a lack of contextual relevance or the inadvertent omission of significant contributions from prior studies. Consequently, a meticulous literature review is a fundamental component of producing high-quality and impactful research. With this in mind, I kindly suggest including a paragraph in the introduction to address the aforementioned aspects.

I transcribe below the same text used in the previous review:

Could the author clarify why the parameters used in the simulations were not included in the methods or methodology section? It might be beneficial for the author to review the structure of the article to better align with the journal’s standards and enhance the reader’s understanding.

Specific Comments

The following list contains my comments on each section, most of which were carried over from my previous review:

A. Abstract

2. "Using this small parameter." Which parameter is being referred to as "small"? Could you clarify why this adjective was chosen?

A. Introduction

1. Page 1, lines 23-25. “and, in addition, plays an important role in solving the problem of recycling electronic devices, which is now of paramount importance all over the world [12-16]”. As the author is discussing applications of ultrasonic systems, it would be more appropriate to cite studies that specifically utilized ultrasound. If I understand correctly, only 16 of the cited references utilized ultrasound. Is that correct?

Answer: “The dependence of the degree of stimulation of many processes by ultrasound on its intensity is well known [20]. As a rule, it grows with the increase in the amplitude of ultrasound (up to a certain limit, of course). The purpose of this work is to propose a method for delivering high-intensity ultrasound pulses over a long distance with minimal wave energy losses”.

The text related to reference 20 addresses the following question: "At the same time, the standard use of ultrasonic devices in a liquid or gas occurs through the excitation of harmonic oscillations in them with the help of probes, hydrophones, and various sensors [20]." In light of this, I stand by the comment made during the first review of this work.

B. Section 2

1. Page 3. It is important for the author to describe all the parameters used in Equations 4 and 5. Additionally, could the author clarify what "c" represents?

Answer: The value "c" has been written below Eq. (5) and represents the velocity of sound for linear limit.

I apologize, but I could not find this information in the text. If the "c" parameter is not defined in the text, please do so. If the author reviews the study by Gusev and Rudenko (2013), they will notice that the researchers provided a detailed description of all the parameters used in their research, including the constants.

2. 8. Page 5, lines 192-194. “The similar approach was used in the papers [27,28] for solving nonlinear problems in plasma. The application of a similar method in a liquid 193 was presented in the paper [7] for video pulses stimulated a liquid extraction”. The reader might question the differences between the present study and those cited by the author. It would be helpful to clarify this in the discussion section.

Answer: The related discussion has been added into the conclusion section.

Below, I have transcribed a fragment from the "Instructions for Authors" provided by this journal:

Discussion: Authors should discuss the results and how they can be interpreted in the context of previous studies and the working hypotheses. The findings and their implications should be examined in the broadest context possible, with the limitations of the work clearly highlighted. Future research directions may also be mentioned. This section may be combined with the Results.

In light of this, I recommend that the analysis suggested in the first review of this manuscript be performed thoroughly, including proper citation of the studies being compared to this one.

3. It is important for the author to describe all the parameters used in Equations 14, 15, 16 and 17. The text does not define certain parameters, such as ω, τ, k, c.c., ε, Ω, δ, B₁ and ξ. Could you clarify what these parameters represent? In physics, constants hold specific meanings, and many are associated with units.

4. Page 6, lines 205-217. It is essential for the author to specify in the manuscript the software used for performing simulations and conducting numerical analyses of the data.

5. Page 7, figure caption. Please, replace “0,5” with “0.5”. Additionally, could you clarify why the author assigned a value of 0.5 to this parameter group? It would be helpful if this rationale were included in the text.

C. Section 3

1. Page 9. It is important for the author to describe all the parameters used in Equation 23.

2. Page 11, Figure 4. I understand that Figure 4 was distorted during its transformation within the Journal. However, it would be helpful if the author could provide additional details about the figure in the text. For example, what do "27.11" and "H, 1, 1" represent? Do the gray columns signify identical values?

D. Conclusion

Comments for author File: Comments.pdf

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 3

Reviewer 1 Report

Comments and Suggestions for Authors

Comments

Overall, the author appeared to focus on countering the comments provided in the earlier review rather than using them constructively to enhance the quality of the work.

1. “Answer: Unfortunately, I did not understand which paragraph should be included in the Introduction. What should it be about? If something may be omitted, then, in my opinion, this does not harm the content of the article”.

Comment: To enhance the introduction of the study and emphasize its originality and relevance, the authors are encouraged to include a paragraph that presents the state of the art on the subject matter. This paragraph should briefly summarize the key research or advancements in the field, highlighting existing gaps, controversies, or areas that remain underexplored. Such context will enable readers to better understand the framework in which the study is situated and how it contributes to advancing knowledge in the field.

For instance, the authors might outline current approaches, their limitations, and how this study proposes an innovative solution or complements prior research. This contextualization will strengthen the rationale for the study and underscore its academic or practical significance.

2. Author's comment: “The parameters that were used in the numerical decisions are of no scientific value, and it seems to me difficult to pass them off as some kind of achievement”.

Comment: The study aims to demonstrate that the proposed method can effectively deliver high-intensity ultrasound pulses over long distances with minimal energy loss. Without providing complete information, other researchers will lack a solid starting point to initiate their studies. Additionally, the absence of such details makes it impossible to reproduce this study

3. Previous comment: The text related to reference 20 addresses the following question: "At the same time, the standard use of ultrasonic devices in a liquid or gas occurs through the excitation of harmonic oscillations in them with the help of probes, hydrophones, and various sensors [20]." In light of this, I stand by the comment made during the first review of this work.

Answer: The question of "the influence of the acoustic signal structure on process intensification and the effectiveness of ultrasound stimulation" is not considered in this article and its discussion is beyond the scope of the presented work”.

Comment: In light of this comment, the reviewer would like to ask the author about the relevance of the following excerpt to the present study:

“At the same time, the use of ultrasonic devices has already become common in a wide range of industrial applications from metal hardening [17] to cleaning soils from inorganic pollutants [18] or stimulating oil wells [19]. At the same time, the standard use of ultrasonic devices in a liquid or gas occurs by excitation of harmonic os36 cillations in them with the help of probes, hydrophones, and various sensors [20]”.

After analyzing the author's comment, the reviewer believes that this excerpt is irrelevant. It would be more beneficial to implement the suggestion provided in the first review, as emphasized in the corrections: to present the state of the art of the present study. The study presented by Barry et al. offers valuable insights for researchers seeking to write effective state-of-the-art paragraphs in their scientific articles.

Barry ES, Merkebu J, Varpio L. How to Conduct a State-of-the-Art Literature Review. J Grad Med Educ. 2022 Dec;14(6):663-665. doi: 10.4300/JGME-D-22-00704.1. PMID: 36591421; PMCID: PMC9765899.

4. Previous comment: It is important for the author to describe all the parameters used in Equations 4 and 5. Additionally, could the author clarify what "c" represents?

Answer: The value "c" has been written below Eq. (5) and represents the velocity of sound for linear limit.

Previous comment: I apologize, but I could not find this information in the text. If the "c" parameter is not defined in the text, please do so. If the author reviews the study by Gusev and Rudenko (2013), they will notice that the researchers provided a detailed description of all the parameters used in their research, including the constants

Answer: The parameter "c", just like the other parameter "χ", is a constant and is expressed in terms of the characteristics of the fluid using the formulas given in (5). There is no need to discuss these constants in the text of the article, in my opinion.

Comment: In my opinion, the requested information should be included in the manuscript to ensure the study is replicable by other researchers. It is important for readers to fully understand the methods used in the study and how to address any gaps that were not explored in the current research.

5. Comment: The equations presented include various parameters; however, their meanings were not explained. You merely stated that they are conditions or constants. I maintain the same comment as previously stated.

Example: “The properties of nonlinear wave formations can be described most simply when they are excited when the condition ε = z0/R << 1 is fulfilled, i.e. when the characteristic scales of wave change in different directions”

6. Author's comment: “In numerical calculations, publicly available mathematical software was used. To present it in the text of the article is to me the equivalent of mentioning that I used paper of a certain quality and a pen of a certain brand, as well as a computer of a certain brand, for calculations and writing. For me, this is undesirable, because I would like to look like a normal person in the eyes of readers”.

Comment: This comment is inappropriate, as comparing data using different statistical software often yields slightly different results; a brief search of the literature would confirm this. In addition, implementing algorithms to perform simulations in Matlab, Mathematica, or Python can yield slightly different results, even when using identical models and parameters. This variation arises from differences in numerical algorithms, solution methods, precision, and randomness management across these software platforms.

Therefore, it is essential for readers to be aware of the specific software used in a study to ensure reproducibility.

Author's comment: The article introduces the concept of relative "efficiency" of one type of radiation in relation to another "H". This value is shown in Fig.4 in the form of columns for the three examples of stimulation considered. The number "27.11" indicates the value of "H" for the first example discussed. The value of "1" indicates the relative effectiveness of radiations with the same degree of impact. Columns of this size are for comparative purposes. The amplitude “A” is explained in the formula (23).

Comment: This information should be clearly stated in the text.

Author Response

Please, see the attachment.

Author Response File: Author Response.pdf

Round 4

Reviewer 1 Report

Comments and Suggestions for Authors

The dedication to enhancing the quality of the manuscript and the thoughtful consideration given to the comments are genuinely appreciated. It is evident that significant effort and care have been invested in producing a high-quality study, which is truly commendable.

Please rest assured that our goal is aligned: to refine the manuscript and ensure it meets the highest standards. I understand that some comments may be challenging to address fully, and I remain committed to working collaboratively with you through this process.

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“As the reviewer noted in the following commentary below, "The study aims to demonstrate that the proposed method can effectively deliver high-intensity ultrasound pulses over long distances with minimal energy loss." Unfortunately, I am not aware of any key studies, achievements, or works in this area in general that would pose and solve such a problem. If the Reviewer knows anything about the existence of such works, I would be very grateful for that information. It would then be possible to summarize key research or achievements in the field, highlighting existing gaps, contradictions, or areas that remain underexplored”.

In light of this comment, I kindly suggest that the author include in the introduction a statement highlighting the lack of studies addressing the topic analyzed in this research.

Author Response

The necessary addition has been installed to the text of the manuscript