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The performance of oil-filled pressure cores is very much affected by the corrugated diaphragm and the oil filling volume. The purpose of this paper is to show the effects of different corrugated diaphragms, different oil filling volumes and different treatments of the corrugated diaphragms on the performance of pressure sensors.

Pressure-sensitive cores with different diaphragm diameters, different diaphragm ripple numbers and different oil filling volumes are produced, and thermal cycling is introduced to improve the diaphragm performance, and finally the performance of each pressure-sensitive core is tested and the test data are analyzed and compared.

The experimental results show that the larger the diameter of the corrugated diaphragm used for encapsulation, the better the performance. For pressure-sensitive cores using smaller diameter corrugated diaphragms, the performance of one corrugation is better than that of two corrugations. When the number of corrugations and the diameter are the same size, the performance of the outer ring of the diaphragm with concave corrugations is better than that with convex corrugations. At the same time, the diaphragm after thermal cycling treatment and appropriate reduction of encapsulated oil filling can improve the performance of the pressure-sensitive core.

By exploring the effects of corrugated diaphragm and oil filling volume on the performance of oil-filled pressure cores, the design of oil-filled pressure sensors can be guided to improve sensor performance.

Particles are of the controlled release delivery systems. Also, topically applied olive oil has a protective effect against ultraviolet B (UVB) exposure. Due to its sensitivity to oxidation, various studies have investigated the production of olive oil particles. The purpose of this study was to use chitosan and sodium alginate as the vehicle polymers for olive oil.

The gelation method used to prepare the sodium alginate miliparticles containing olive oil and particles were coated with chitosan. Morphology and size, zeta potential, infrared spectrum of olive oil miliparticles, encapsulation efficiency and oil release profile were investigated. Among 12 primary fabricated formulations, formulations F₅ (olive oil loaded alginate miliparticles) and F₁₁ (olive oil loaded alginate miliparticles + chitosan coat) were selected for further evaluations.

The size of the miliparticles was in the range of 1,100–1,600 µm. Particles had a spherical appearance, and chitosan coat made a smoother surface according to the scanning electron microscopy. The zeta potential of miliparticles were −30 mV for F₅ and +2.7 mV for F₁₁. Fourier transform infrared analysis showed that there was no interaction between olive oil and other excipients. Encapsulation efficiency showed the highest value of 85% in 1:4 (olive oil:alginate solution) miliparticles in F₁₁. Release study indicated a maximum release of 68.22% for F₅ and 60.68% for F₁₁ in 24 h (p-value < 0.016). Therefore, coating with chitosan had a marked effect on slowing the release of olive oil. These results indicated that olive oil in various amounts can be successfully encapsulated into the sodium-alginate capsules cross-linked with glutaraldehyde.

To the best of the authors’ knowledge, no study has used chitosan and sodium alginate as the vehicle polymers for microencapsulation of olive oil.

“This article is mainly concerned with swarf produced by machine tools using neat cutting oils. If the factory has no means of extracting the oil from this, anything from 40 to 80 gal/ton swarf will be carried away on the scrap dealer's lorry. But it can be a messy and uneconomic proposition if no thought is given to it”.

The purpose of this paper is to evaluate local biodegradable oils with long chain fatty acids namely: castor (Ricinus communis L.), jojoba (Simmondsia chinensis L.), olive (Oleo europaea L.), and sunflower (Helianthus annuus L.) oils for lubrication candidacy as a substitute to petroleum mineral oils.

Evaluation criteria includes antiwear, lubricity, and extreme pressure (load carrying capacity) using the four‐ball configuration, oxidation induction by pressure differential scanning calorimetry, thermal stability by thermo‐gravimetric analyses, and viscometry using relevant American Society of Testing and Materials (ASTM) standards.

The results show that the lubrication films at the interface failed by the decomposition of the metallic soaps formed by the chemical reaction of the constituent fatty acid molecules and the rubbing surfaces. The biodegradable oils show superior lubricant performance compared to the paraffin‐based mineral oil, despite their poor oxidation stability. Oxidation induction and thermo‐gravimetric characteristics of the biodegradable oils are closely related to their polyunsaturated and monounsaturated fatty acid composition.

The paper shows how these biodegradable oils could be used as good substitute for petroleum mineral oils in as‐received state or little antioxidant additives.

The lubricating oil is a non‐renewable source of energy and its useful life is limited due to deterioration during its usage. It is desirable to maximize its use to conserve this scarce resource. At present, continuation or change of the engine oil is decided, based on the manufacturer's recommendation and experience. The suggested engine oil change period is conservative and results in non‐efficient usage of engine oil. This practice needs refinement to include all possible properties/attributes of engine oil and use of appropriate procedure to assess its realistic performance. The paper aims to analyze the procedure.

Oil reliability polygraph is used to analyze the engine oil performance during operation. Reliability analysis of the engine oil is carried out by comparing the area of oil reliability polygraph at a given operation time with the area for the fresh engine oil. The suggested procedure is illustrated by means of an example.

Physical and chemical properties responsible for performance degradation of the engine oil are considered as engine oil reliability attributes. The value of these attributes from time to time, obtained by analyzing samples drawn from the system, is analyzed through oil reliability polygraph. In this approach, the engine oil reliability attributes at a given operation time are represented in terms of reliability value to obtain the “oil reliability polygraph”.

The suggested procedure will be helpful for maintenance personnel in taking planned maintenance action.

The purpose of this paper is to characterize oils extracted from Bertholletia excelsa, Lecythis pisonis, Dipteryx lacunifera, Carya illinoensis and Juglans regia, regarding their characterization and fatty acid profile.

The oils were extracted from oilseeds by cold pressing and physico‐chemical characterization was performed by using standard methods for oils and fats. The oxidative stability and fatty acid profile also were determined.

According to the results, the physico‐chemical properties of oils from nuts and walnuts were comparable to those of good quality conventional oils. The oil seeds are a good source of unsaturated fatty acids, especially oleic and linoleic acids.

Implies the identification of fatty acid profile and physico‐chemical properties of oils extracted from nuts and walnuts, and to prevent certain types of diseases.

The paper identifies a new source of essential fatty acids extracted from oilseeds.

ABOUT ten years ago in the United States oils of the “detergent” type had come into rather general use for some diesel engine operation because they permitted longer periods of satisfactory operation than could be obtained with plain mineral oils. Since that time accumulated research and field service have shown that “detergent” type oils could be utilized to advantage and their field of use has broadened. How then can they be defined?

The decrease in availability of mineral oils and their environmental hazards created the need to search for alternate bio-based oils. The aim of this study is to investigate the friction and wear characteristics of kapok (Ceiba pentandra) oil as a bio-lubricant.

The wear and friction characteristics between steel-steel contact under lubrication were found using a pin-on-disk tribometer under different loads and sliding speeds, respectively. The corrosion and oxidation stability of the test lubricants were also analyzed. The worn surfaces of the specimen are analyzed with the help of an optical microscope. The obtained results were compared with palm oil and mineral oil (SAE20W 40).

From the investigation, it is found that the kapok oil possess a lower coefficient of friction and wear rate than palm and mineral oil. It is also found that the coefficient of friction varies proportionally and the wear rate varies inversely with the sliding speed as expected.

The present results confirm that the kapok oil can be used as an alternative lubricant to reduce the demand for mineral-based oil lubricants.

The steam engine was the first practical means of producing mechanical power from the heat of combustion of a fuel, and its introduction was a vital factor in the progress of the Industrial Revolution. For many years the development of the steam reciprocating engine continued apace, but in the early years of the present century introduction of the steam turbine and internal combustion engine made available alternative methods of power production. From then on interest in the steam reciprocating engine tended to slacken and, although it has shown a number of notable improvements, far more spectacular advances have been made in other power units.

Oil‐in‐water (O/W) emulsion has been used in industrial rolling mills for many decades, but its lubrication mechanism is still not adequately understood. There is a need to understand the role of chemical ingredients and emulsifier in lubrication and tribological characteristics of rolling oil. With this purpose, the authors selected three commercially available O/W emulsions of different generations and of known industrial performance. The aim is to understand the lubrication mechanism of these rolling oils and to correlate the laboratory findings with that of industrial rolling mills.

The lubrication mechanism has been studied with the help of an ultra thin film interferometry EHD test rig, an advanced experimental rolling mill and a Coulter LS 230 instrument. Film thickness, rolling parameters and droplet size were measured. The coefficient of friction was computed with the help of the measured values of rolling parameters. Emulsion stability and saponification value (SAP) of the selected emulsions were also determined. The results of film thickness, rolling parameters and droplet size have been presented. The lubrication mechanism of the emulsions has been explained on the basis of film thickness, droplet size, emulsion stability, SAP value and coefficient of friction.

Results of the present study reveal that chemistry of O/W emulsions plays an important role in their film forming and tribological behavior. Rolling emulsions of relatively low stability, higher droplet size and high SAP value are found to provide better lubrication and lower coefficient of friction. The results of the present study correlate well with the actual industrial experience except those obtained on EHD test rig.

Coulter LS 230 instrument was available with M/s LUBRIZOL CORP., USA. Only limited study on droplet size was carried. Although the study carried out has given good information but it would have been more practical if the emulsion samples taken from the experimental mill stand would have been studied for droplet size.

From understanding point of view of lubrication mechanism of O/W emulsion, it will be useful for oil technologists, tribologists and rolling mill users.

The study is original in nature and gives information on lubrication mechanism of O/W emulsions in steel cold rolling of steel strips.