Study on Heat Transfer Performance and Anti-Fouling Mechanism of Ternary Ni-W-P Coating

Round 1

Reviewer 1 Report

The manuscript entitled " Investigation on Heat Transfer Performance and Anti-fouling Mechanism of Ternary Ni-W-P Coating "  deals with the assessment of a surface morphology, microstructure, fouling behavior and heat transfer performance of Ni-W-P coatings.

 

The paper is very interesting but some changes should be addressed

Abstract: Describe the abbreviation of Ni-W-P when it is used the first time in the text.

 

Keywords: should be in alphabetical order, KEYWORDS should not contain the same words that are within the title of the text.  Thus these should be changed appropriately

Also, some minor spell check is required.

Author Response

Referee #1: General comments: Comment 1: Abstract: Describe the abbreviation of Ni-W-P when it is used the first time in the text. Answer: Many thanks for the comment of our insufficient work. Ni-W-P in the manuscript represents for the ''nickel-tungsten-phosphorus''. Finally, we checked the whole manuscript, and corrected similar problems to avoid ambiguity. We hope that this new version will be reasonable. Comment 2: Keywords: should be in alphabetical order, KEYWORDS should not contain the same words that are within the title of the text. Thus these should be changed appropriately Answer: I apologize for making an incorrected keyword. We modified the order of KEYWORDS and the inappropriate keywords as, Keywords: Anti-fouling performance; First principle; Heat-transfer characteristic; Surface modification; Thermal conductivity; Transient state. Comment 3: Also, some minor spell check is required. Answer: Thank you for giving your comment which would help us both in English and in depth to improve the quality of the paper. In order to improve the language level of this paper, we ask a language-edit services for help. Besides, to avoid unnecessary technical error, we have asked for the English-speaking colleague (Prof. Qingguo WANG) to check our manuscript word by word, then we revised the manuscript both in English and in depth to improve the quality of the paper. Many thanks for the comment of our insufficient work. The modified statements have been highlighted in the modified manuscript.

Author Response File: Author Response.docx

Reviewer 2 Report

The manuscript "Investigation on Heat Transfer Performance and Anti-fouling Mechanism of Ternary Ni-W-P Coating" by Ren et al. evaluates the use of a ternary Ni-W-P coating to inhibit the fouling deposition.

This manuscript is well structured and written. The experimental design proposed in the manuscript allows the authors to respond to most of their objectives. This paper describes the results derived from well-designed experiments.

Nevertheless, the authors should make some changes before getting their manuscript accepted for publication. The comments from the reviewer are listed below:

 

1. The authors should follow MDPI and Applied Sciences authors' instructions for the editing of their manuscript.
2. They should use IS units and abbreviations (i.e., hours h)
3. The authors should run some statistical analysis for a better comparison of the quantitative data.
4. The experimental section should be extended to include surface morphology experiments, scanning electron microscope (SEM), energy dispersive spectroscopy, and X-Ray diffraction studies.
5. The authors should decide to merge results and discussion sections, whether reorganize them. The results section should not include references or comparisons with previous studies. On the contrary, all this information should be included in the discussion section. A merged section could also be appropriate.

Author Response

Referee #2: General comments: Comment 1: The authors should follow MDPI and Applied Sciences authors' instructions for the editing of their manuscript. Answer: Thank you for the comments on this. As required, we follow MDPI and Applied Sciences authors' instructions for the editing of their manuscript.; a) MDPI template has been utilized to correct the format of manuscript. b) We checked all the mechanisms in the manuscript and the inappropriate expressions have been modified. c) Equations are stored and can be used for typesetting. We supplied symbol expression near the related equations. d) Grammar and sentence pattern have been improved. Comment 2: They should use IS units and abbreviations (i.e., hours h) Answer: Thank you for giving your comment. We re-edit the IS units and abbreviations and inconformity expressions have been modified in the manuscript. ''℃'' to ''K'', ''mg'' to ''g'', '' hours'' to ''h''. Besides, units in Tab.4, Fig.8 and Fig.9 have been modified as required. Comment 3: The authors should run some statistical analysis for a better comparison of the quantitative data. Answer: Thank you for this comment. However, I am not quite sure for the statistical analysis process. The error bars have already been added in all figures while the results of some multiple quantitative data are consistent. To be convincing, more references have been supplied in the manuscript to make the comparison. Comment 4: The experimental section should be extended to include surface morphology experiments, scanning electron microscope (SEM), energy dispersive spectroscopy, and X-Ray diffraction studies. Answer: Thank you for giving your comment. As required, we supplied the experimental section 2.3 on surface morphology, microstructure and phase composition. The related expression can be show as follow, 2.3. Surface morphology, microstructure and phase composition After the specimens were fouled for a set time, specimens with fouling were taken out. After the process of fouling adhesion, surface morphology of fouled specimen and Ni-W-P coating were characterized by means of a scanning electron microscopy (SEM, Model QuantaTM250, FEI, USA). Elementary changes of Ni-W-P coating were analyzed with energy dispersive spectroscopy (EDS, Model QuantaTM250, FEI, USA). Crystal forms of fouling on the surface of Ni-W-P coating and bared mild steel were studied with the method of X-ray diffraction (XRD, D8 ADVANCE, Bruke, Germany). Through the results of scanning electron microscopy and X-ray diffraction on different surfaces. Different phase calcium carbonate can be determined. Comment 5. The authors should decide to merge results and discussion sections, whether reorganize them. The results section should not include references or comparisons with previous studies. On the contrary, all this information should be included in the discussion section. A merged section could also be appropriate. Answer: Thank you for giving your comment. In the result section, we described the results of material characteristics, heat transfer behavior and adsorption properties, separately. However, in the discussion section, we analyzed the results uniformly. Thus we do think that the classification is necessary. In order to evidence the experimental consequences, we quoted some references and previous publications and compared the results with them. Of course, the comment you have mentioned is very vital for us. We have improved the structure and text in the manuscript and we also deleted unnecessary references.

Author Response File: Author Response.docx

Reviewer 3 Report

This paper shows the effect of Ni-P-W on calcareous deposition. Samples with different W concentration are evaluated. The topic of paper is interesting.

Some general comment: more details about experimental apparatus and geometry could be introduced (form and samples position, dimension of plant – see point to point comment).

In all text and captions: pay attention to subscript and apex of chemical formula

The text need a revision improving the quality of figures and discussion. Particularly considering the figures more comparisons with uncovered substrate result necessary. Considering some figures, it is preferable to increase the clearness to split in two figures (see comments point to point)

 

Following The number on the left is the line number.

In abstract:

17: Indicate details about the Ni-W-P coating deposition

36: describe also the presence of corrosion products

88. The form of samples is cylindrical? Part of tube? only continuing reading the text it is possible to understand.

97: table 3: introduce the measure units of electro-less bath deposition

93-95. Introduce other information about deposition of coatings: pH, bath stirring, temperature control.

96: table 2: introduce the polishing effect of Po1yoxyethylene octylphenol ether

107-108: supersaturation solution of CaCl₂ and NaCO₃? Calcium-carbon is not correct.

124: fig 2: correct the chemical formula: subscript and apex. Highlight the sample position (also in fig.3)

123: why the stainless steel limited the deposition of calcium carbonate?

130 and foll.: description of parameters of all equations (for ex. for eq.1:  m1 = mass ….). Pay attention to subscript and apex in the text.

152: why corrosion product (red rust) is present on external surface (in particular on the right)

135- 151 and 154-164: introduce refs.

165: what means “material studio”

192-194:  from figures 4 it is not possible to affirm the followed sentence “As shown in Fig.4c and 4d, brown products and plenty of white particles deposited on the surfaces of the specimen. The coated surface is still dense without pores. Compared with the fouling on the surface of bare substrate in Fig.4c, we can clearly notice that the amount of fouling on the coated surface (Fig.4d) is conspicuously thinner than uncoated one.”. Change the figures with high magnification. Use the same magnification and illumination of pictures. What are the colored area (red on sample 4C and black-gray on sample 4d)?

213: increase the quality of fig. 4 caption

212: in fig. 4e introduce the mass change with uncoated sample too. Fig.4a and 4b are not useful at this magnification: it is not possible to note the differences.

204: from fig.4e it possible to conclude that no influence W content in the coatings, as highlighted by authors (“Fig.4e, the result reveals that the fouling on the surface of the specimen did not change significantly with the increase of W content”). However, considering the dispersion data, a strange result is observable: the differences among samples are high without a clearly correlation. Could be a connection with the mass measurement methods?

This part must be improved

217. The part connected with fig. 5 – structures of deposits must be improved.

Introduced SEM pictures of cross section of all samples (but from metallographic mirror polished samples).

The “furuncle”: is better: globular morphology or nickel accumulation, typical of electroless nickel.

Separate the fig. 5: it is better to made two figures: one with SEM micrographs and one with EDS chemical analysis.

219-220: “(d) Cross-sectional 219 image of Ni-W-P coating of specimen 1; (e) Cross-sectional image of Ni-W-P coating of specimen 5;” ERROR! Both figures are related to the same area of the same sample (one in BSE one in SE detector!!)

231: “thickness distribution of Ni-W-P coating after 3 hours plating is 20μm±2μm” ? at line 92 is written 2 hours of deposition!

244-245: “Compared with specimens coated with ternary Ni-W-P coatings in Fig.6c-6f, the deposited product layers were much thinner” it is not possible to have a correct information about thickness of deposits using picture of surface.

246: “Additionally, there is un-conspicuous fouling in some areas where the cell bodies of ternary Ni-W-P coatings in Fig.6a could be observed” considering the caption: 6a is uncoated sample

273: split the fig. 8d in two figures.

368 and 394: introduce in fig. 10a the contact angle data of uncoated sample. The behavior (surface free energy) of sample 40 is not clear comparing the other data and the trend with increase of W presence. Introduce justification

408: subscript and apex in chemical formula in the table caption

About references:

Very ref 33: NH₃ not Nh3

 

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 3 Report

Line 5-: pay attention to the dimension of character and of the numbers (1 and 2 after China and South Africa in not necessary)

Line 17: .

Line 157: introduce ref. about the influence of s.s. on the reduction of the carbonate deposits quantity

Line 223: thanks for information, however it is better to write: “Material Studio 8.0 software"

Line 171: Caption of fig.4: please check if the assignment of the figures is correct:comparing with the first version, the bare surface could be 4b.

line 356: pay attention at the dimension of the characters: q_m1 is different than q_m2

line 448: “Contact angle and surface energy of uncoated specimen and the Ni-W-P coatings"

line 509: CaCO₃   (pedex)

about references: some ref.s are not in the standard. For example:  ref 8: names of authors are in capital; ref. 15 the same; ref.61: Caco3 change in CaCO₃ ref 36: NH₃. Check all references considering the Journal instruction

Author Response

Referee #3:

General comments:

Comment 1: Line 5-: pay attention to the dimension of character and of the numbers (1 and 2 after China and South Africa in not necessary)

Answer: The dimension of character and of the numbers have been checked and thank you for your careful review.

 

Comment 2: Line 17: .

Answer: We apologize for making an omission. “.” has been supplied as required.

 

Comment 3: Line 157: introduce ref. about the influence of s.s. on the reduction of the carbonate deposits quantity

Answer: Thank you for this comment. Reference has been introduced as required. Please kindly find it in the manuscript.

 

Comment 4: Line 223: thanks for information, however it is better to write: “Material Studio 8.0 software"

Answer: Thank you for this comment. The expressions have been improved as required.

 

Comment 5: Line 171: Caption of fig.4: please check if the assignment of the figures is correct: comparing with the first version, the bare surface could be 4b.

Answer: We apologize for making a mistake and thank you for your careful review. The fig.4 caption have been modified.

 

Comment 6: line 356: pay attention at the dimension of the characters: qm1 is different than qm2

Answer: Thank you for this comment. Variate size of q_m1 and q_m2 were modified. We will avoid such problems in the future.

 

Comment 7: line 448: “Contact angle and surface energy of uncoated specimen and the Ni-W-P coatings"

Answer: Thank you for this comment. The figure caption in line 448 has been modified in the manuscript.

 

Comment 8: line 509: CaCO3   (pedex)

Answer: Thank you for this comment. “CaCO3” has been modified “CaCO₃”.

 

Comment 9: about references: some ref.s are not in the standard. For example:  ref 8: names of authors are in capital; ref. 15 the same; ref.61: Caco3 change in CaCO3 ref 36: NH3. Check all references considering the Journal instruction

Answer: Many thanks for the comment of our insufficient work. All references styles have been checked as required of Journal instruction.

Author Response File: Author Response.docx