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Applied Surface Science 273 (2013) 570–577 Contents lists available at SciVerse ScienceDirect Applied Surface Science jou rn al h om epa g e: www.elsevier.com/locate/apsusc Tribological and stability investigations of alkylphosphonic acids on alumina surface M. Cichomski a,, K. Ko´ sla a , J. Grobelny a , W. Kozłowski b , W. Szmaja b a University of Łód´ z, Faculty of Chemistry, Department of Materials Technology and Chemistry, Pomorska 163, 90-236 Łód´ z, Poland b University of Łód´ z, Faculty of Physics and Applied Informatics, Department of Solid State Physics, Pomorska 149/153, 90-236 Łód´ z, Poland a r t i c l e i n f o Article history: Received 31 October 2012 Received in revised form 28 January 2013 Accepted 14 February 2013 Available online 27 February 2013 Keywords: Alkylphosphonic acids Alumina surface Tribology X-ray photoelectron spectroscopy Time of flight secondary ion mass spectrometry Fourier transform infrared spectroscopy a b s t r a c t Alumina substrates are commonly used for various micro-/nanoelectromechanical systems (MEMS/NEMS). For efficient and lifetime longevity of these devices, lubricant films of self-assembled monolayers (SAMs) with nanometer thickness are increasingly being employed. In the present paper, we report preparation, tribological and stability investigations of alkylphosphonic acids on the alumina surface. The alkylphosphonic acids were prepared on the alumina surface using the liquid phase deposition method. The effectiveness of modification of the alumina surface by alkylphosphonic acids was investi- gated using water contact angle measurements, secondary ion mass spectrometry, X-ray photoelectron and infrared spectroscopy. Frictional behavior in milinewton load range was studied by microtribometry. It is shown that surface modification of the alumina surface by alkylphosphonic acids reduces the coefficient of friction values compared to the unmodified alumina. In comparison to the non-modified alumina surface, all tested alkylphosphonic acids cause a decrease in the friction coefficients in friction tests for counterparts made from different materials, such as steel, zirconia and silicon nitride. It is also found that the alumina surface modified by alkylphosphonic acids with longer chain has a higher degree of hydrophobicity and lower coefficient of friction. The best frictional properties are obtained for the system consisting of the alumina surface modified by n-octadecylphosphonic acid and silicon nitride counterpart. Stability tests in different environmental conditions: laboratory, acidic and alkaline solutions were also monitored. © 2013 Elsevier B.V. All rights reserved. 1. Introduction The surface modification of metal oxides is of great inter- est due to their significance in biomaterials [1], catalysts [2], inorganic-organic hybrid materials [3] and membranes [4,5]. A major approach for the surface modification of metal oxides uses the covalent attachment of organic coupling molecules, which may form monolayers on the surfaces of these materials. Over the last two decades, phosphonic acids of the type RPO(OH) 2 (R = alkyl or perfluoroalkyl chain) have received much attention as coupling agents in metal oxides. These molecules have a linear hydrocarbon chain with a phosphonic acid head group (phosphorus tetrahedrally bonded to carbon, oxygen atoms and two hydroxyl groups) at the terminus. The head group is expected to bind to an oxide surface via two or three condensate bonds to sur- face oxygen atoms. This head group can react with surface hydroxyl Corresponding author. Tel.: +48 42 6355836; fax: +48 42 6355832. E-mail address: [email protected] (M. Cichomski). groups of the oxides, such as TiO 2 , ZrO 2 ,Y 2 O 3 or Fe 3 O 4 , via conden- sation reactions, resulting in the formation of covalent bonds [6,7]. The alkyl chains from phosphonic acids are tilted from 31 to 40 , depending on the substrate in which acids form bonds [8]. The phosphonic acids are used for building thin film devices due to their ability to form well-defined and stable films on oxide surfaces. Therefore they are used in a variety of applications to pro- mote the adhesion of polymers to inorganic surfaces such as glass or metal oxide particles. They are also being used for applications in the field of electronics and biosensor development, and studies of their order and uniformity are found to be of large importance. A variety of experiments proved the high stability of the P O M (M = Al, Ti, Zr) bond under various conditions, such as ultraviolet (UV) irradiation, thermal treatment and hydrolysis at different pH values. This is one of the main advantages for using the phosphonic acids. In this paper, two alkylphosphonic acids with different chain length [decylphosphonic acid (DP) and octadecylphosphonic acid (ODP)] are used in investigations. First, we investigated the optimization of liquid phase deposition method parameters for 0169-4332/$ see front matter © 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.apsusc.2013.02.081

North of England Veterinary Medical Association

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Page 1: North of England Veterinary Medical Association


The results of the experiments have, to say the least, been staggering; for, while we find the sheep and guinea-pigs readIly succumhing to inoculation with vIrulent material, the calves, on the other hand, whether inoculated, setoned, or control animals, have alI ~ucce~,fully with~tood its influence. This would appear to indicate that sheep are actually more susceptible to black-leg than calve~ if the virus be directly introduc~d into the system; it lIkewise points to the possibility of many calves being clas~ed as protected by inoculation, when in reality they may have possesoed some mherent immunity from the disease.

It would also seem that the risk of contagion from black-leg, at least so feu as calves are concerned, cannot be yery great.

Finally, they clearly show that the prevention of black-leg by protective inoculation is still, so far as this country is concerned, by no means estab­lished.

liVe regret that the results we furnish you are not more definite; at the same time we think they must be beneficial If they only convince you of the undoubted necessity for further investigation.


A quarterly meeting of this Society, held at N ewca~tle on the 20th of November last, was devoted to a discU5~ion on the leSIons of contagious pleuro-pneumonia in cattle. The meeting was arranged in the expectation that Professors Williams and M'Fadyean would attend and exhibit specimens in support of their respective opilllons regarding the nature of the lesions discovered in the lung of a particular American ox slaughtered at Deptford in April of the present year. Professor Williams declined to comply with this request, but Professor l\I'Fadyean attended and gave a demonstration of microscopic, naked-eye, and lantern sections to prove that the lesions present in the Deptford ox had all the characteristics of cc,ntagious pleuro-pneumonia. The specimens exhibited included sections from the Deptford ox and others taken from home cattle slaughtered for pleuro-pneumonia, and none of the members present were able to distinguish the American specimens in the mixed series exhibited.

Dr Hunter, Lecturer on Physiology In the New Veterinary College, on the invitation of the chairman, then addressed the meetmg. He exhibited a lantern-photograph of a section from the lung of the Deptford ox, and described at great length the histological changes shown in it. These, he contended, were characteristic of catarrhal pneumonia; and he said that although he had at fir~t 5ight of the lung of the Deptford ox inclined to the opinion that the case was one of contagious pleuro, hIS microscopic inve~tiga­tion of the lung had convinced him that it was a case of catarrhal or broncho­pneumonia. In support of this opinion, he exhibited on the screen a photo­graph, from the lung of an ox affected with pleuro pneumonia, this showing no catarrhal changes. He also referred at length to the investigations of Professor N ocard of Paris regarding an infectious form of catarrh:ll-pneumol1la discovered by him in some American cattle ex posed in the Paris mal ket. Dr Hunter contended that the Deptford ox had been the subject of the same disease.

l\Ir Bowhill, of the New Veterinary College, supported the opinions expres~ed by Dr Hunter. He had, he saicl, been able to find in the lung of the Deptford ox bacteria which, in point of shape and size, agreed with those found by Professor N ocard in infectious broncho-pneumonia, or the so-called "corn-stalk disease." That these bacteria were identical with those de"cribed

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by l\1. N ocard he had not been rtble to prove absolutely, as there was no opportunity to test their effects by inoculation.

A lengthy discussion on the part of the members of the Society then took place, every speaker, including Mr Clement Stevenson, of Newcastle; Mr Hunting, senior, of South Hetton ; and Messrs Moore, Hunter, and Elphick, of N ewcrtstle, after reviewing the evidence laid before them by Professor M'Fadyean on the one hand, and Professors Hunter and Bowhill on the other, declared in f<Lvour of the view that the Deptford ox had been the subject of contagious pleuro-pneumonia, and strongly upheld the action of the Board of Agriculture in the mrttter.

Professor M'Fadyertn, in replying at the close of the debate, said that he was much gratified at the conclusion arrived at by the meeting. He confessed that he had listened with considerable impatience to Dr Hunter's description of the lantern photographs. The catarrhal pneumonia shown in the photo­graph of the lung of the Deptford ox, he could parallel from almost every case of genuine pleuro-pneumonia occurring in Bntish cattle. Since Dr Hunter had spoken, lie had submitted to him a number of specimens under the micro­scope. One of these, Dr Hunter admitted, showed lec;ions similar to those that he had found in the Deptford ox. This lung, l'rofessor M'Fadyean informed the meeting, was from an Edinburgh cow, slaughtered while suffering from typical contagious pleuro-pneumonia.

At this stage of the proceedings, Professor M'Fadyean in presence of the meeting passed a specimen to Mr Bowhill, and asked him, after examination, to say what in his opmion the lesion was. l\Ir Bowhill promptly declared that it was catarrhal pneumonia. This also, Professor M'Fadyean explained to the meeting, was from a case of undoubted British contagious pleuro-pneumonw, and he called the attention of the meeting to the fact that he had publicly con­victed both Dr Hunter and l\Ir Bowhill of inability to distinguish genu me pleuro-pneumonia when they saw it under the microscope. In conclusion he said that after the day's proceedings and the opinions which he had been able to lay before them from eminent Continental authorities, no reasonable person could entertain any doubt that the lesions present in the lung of the Deptford ox were not distinguishable from those of contagious pleuro-pneumonia, and in the absence of any clinical history it must be held that the disease was genuine contagious pleuro-pneumonia.

The meetmg was brought to a close with votes of thanks to Professors M'Fadyean, Hunter, and Bowhill.


THE Quarterly Meeting of this Association was held in the J\1edical Institute, Hope Street, Liverpool, on Wednesday, 16th December, Mr Arthur Leather, F.R.C.V.S., President of the Association, in the chair. There was a large attendance of members. Mr Laithwood of Congleton was nominated <IS a member of the Association, and Messrs J. M'Kinna, Huddersfield, H. D. Chorlton, Manchester, and A. Breakell, Garstang, were elected to member­ship.

l\Iessrs LOCKE and TAYLOR reported on the question of obtaining a better l11eeting-place at Manchester, but it was ultimately resolved to remain for the present at the old place of meeting. Mr S. Locke was elected a life govern or of the benevolent branch of the National Veterinary Benevolent and Defence Association, in the room of Mr 'Yoods deceased.

Mr 'Y. A. TAYLOR, in proposing that Mr W. 'Yoods of lYigan be elected President for the ensuing year, said that that gentleman was one who would do credit to the Association. NIr Whittle seconded this, and it was unani-