Surface Attrition Research Articles

Nitrogen Diffusion at Low Temperature in fcc Materials Deformed by Attrition Peening

Recent scientific work has opened new fields of application to mechanical treatments such as shot blasting or peening. Indeed, it has been shown that this treatment, performed before a nitriding treatment on the surface of ferrous alloy, lowers processing temperatures and significantly increases the diffusion kinetics. We undertook to test this combination of mechanical pretreatment and thermochemical treatment on stainless steels and nickel-based alloys. The mechanical treatments were done by surface attrition peening. The pretreated samples were then nitrided at low temperature using remote plasma. In this paper, the results obtained after nitriding treatments on samples treated by attrition peening are compared to those nitrided only. The use of X-ray diffraction, microhardness measurement, observations by optical and scanning electron microscopy, texture analysis by EBSD (Electron BackScatered Diffraction) and measurement of nitrogen concentration profiles by SIMS (Secondary Ion Mass Spectrometry) allows quantifying the effects of the combined treatments.

湿式分級洗浄および天然鉱物等による農地土壌等に含まれる放射性セシウム除去方法の実践的検討

In the radiation dosimetry of radiocesium in Iitate, Fukushima, the level of radiocesium around the environment did not exceed the criteria in liquid phases such as puddle water, but was distributed in solid phases such as some soil types and organic matter. On the other hand, retting of the cut bamboo grass and hemlock fir in water allowed the release of radiocesium, about 230 Bq/kg exceeding the criteria for a bathing area. The flow-thru test using zeolite showed the removal of radiocesium from the liquid phase. The wet classification test was performed for 3 types of radiocesium-contaminated soil. According to the results of wet classification, radiocesium was detected and its level exceeded the cropping restriction level in almost all classified particle fractions. The decontamination effect of wet classification on radiocesium contamination was smaller than that on heavy metal contamination. Specifically, the wet classification could not induce volume reduction. Accordingly, preprocessing and intermediate treatments such as dispersion or attrition by vibration or mixing in the wet classification process were devised and examined as improved processing techniques. As a result, the effectual volume reduction of the radiocesium-contaminated soil was confirmed by adding an intermediate process such as the surface attrition in the vibrator.

Tooth surface attrition and bruxism: an overview

Dental NursingVol. 7, No. 1 ClinicalTooth surface attrition and bruxism: an overviewHazel J FraserHazel J FraserSearch for more papers by this authorHazel J FraserPublished Online:16 Aug 2013https://doi.org/10.12968/denn.2011.7.1.14AboutSectionsView articleView Full TextPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareShare onFacebookTwitterLinked InEmail View article References Cawson RA, Odell EW (2008) Cawsons Essentials of Oral Pathology and Oral Medicine. 7th edn. Elsevier Limited, Philadelphia Google ScholarCoulthard P, Horner K, Sloan P, Theaker E (2003) Oral and Maxillofacial Surgery, Radiology, Pathology and Oral Medicine. Elsevier Limited, Philadelphia Google ScholarGeneral Dental Council (2009) Scope of Practice — who can do what in the dental team. GDC, London Google ScholarLobbezoo F, van Denderen RJ, Verheij JG, Naeije M (2001) Reports of SSRI-associated bruxism in the family physician's office. Orofac Pai. 15(4): 340–6 Google ScholarMurray JJ, Nunn JH, Steele JG (2003) Prevention of Oral Disease. 3rd edn. Oxford, New York Google ScholarPavone BW (1985) Bruxism and its effect on the natural teeth. JProsthet Den. 53(5): 692–6 Crossref, Google ScholarWalmsley AD, Walsh TF, Burke FJT, Shortall ACC, Lumley PJ, Hayes-Hall R (2002) Restorative Dentistry. Churchill-Livingston, Edinburgh Google Scholar FiguresReferencesRelatedDetails 1 January 2011Volume 7Issue 1ISSN (print): 1749-6799ISSN (online): 1759-7404 Metrics History Published online 16 August 2013 Published in print 1 January 2011 Information© MA Healthcare LimitedPDF download

The burial of Bad Dürrenberg, Central Germany: osteopathology and osteoarchaeology of a Late Mesolithic shaman's grave

AbstractThe isolated burial of Bad Dürrenberg is one of the richest Mesolithic graves in Europe. Although it was excavated in the 1930s, new spectacular anthropological and archaeological evidence has emerged during a recent re‐study. Firstly, we present here the results of an anthropological re‐evaluation of certain features of the skull base and the foramen magnum. Our work has clearly established that the observable features are caused by an anatomical variation that also includes an atlar anomaly. This developmental variation possibly caused various neuropathological symptoms. The Bad Dürrenberg burial consequently represents a unique case of the possible interpretation of abnormal behaviours in a shamanistic fashion in a prehistoric context. Secondly, we have identified the LSAMAT phenomenon (Lingual Surface Attrition of the Maxillary Anterior Teeth) in the adult individual of the burial. The activities leading to this condition are unknown so far. Thirdly, a split roe deer metatarsus among the burial goods was identified as being involved in the preparation or application of red pigment. The lack of polish and other use wear make it likely that it was produced and used as part of the burial ritual. Copyright © 2006 John Wiley & Sons, Ltd.

Brewing beer: status, wealth and ceramic use alteration among the Gamo of south-western Ethiopia

Ethnoarchaeological research among the Gamo people of south-western Ethiopia indicates that pottery vessels used for beer fermentation have characteristic interior surface attrition. The Gamo's strict social hierarchy orchestrates who produces and consumes beer: ritual-sacrificer households are able to produce and consume more beer than non-ritual-sacrificer households and this pattern also was found in the ceramic inventories of the two types of household. The Gamo example suggests that the study of ceramic use alteration can be an additional tool in identifying the production of beer, the essential ingredient of feasting.

Shaping technology of coal gas sorbents by using a spray dryer

The goal of this study was to develop HTHP sorbents for adaptation in fluidized bed desulfurizers or Transport Reactors. For this purpose, we shaped zinc-based sorbents (ZAC series) by using a spray dryer with a pressurized nozzle atomizer. To prepare the slurry for spraying, raw materials in submicron units and organic additives were used. We characterized the sorbents by SEM, XRD, Mean Particle Size Analysis, BET Surface Area and Attrition Ratio. The mean particle size was about 112 μm, the attrition resistance was very good and the TGA sulfur capacity of the fresh sample was calculated at about 23–24 wt%.

Pottery use-alteration as an indicator of socioeconomic status: An ethnoarchaeological study of the Gamo of Ethiopia.

The use of a pottery vessel leaves markers on the ceramic wall that can inform archaeologists how the vessel functioned in the past. At present, archaeologists have little information for understanding how use-alteration reflects the complex nature of ceramic function and socioeconomic status. I conducted a 2-year ethnoarchaeological research project among the Gamo people of southwestern Ethiopia, who continue to produce and use pottery on a daily basis. This research indicates that interior surface attrition occurs primarily on pottery vessels used in wealthy households because of fermentation processes from high-status foods. Thus, the Gamo example suggests that there is a relationship between ceramic use-alteration and household socioeconomic status.

Vessel Form and Function in an Early Formative Ceramic Assemblage from Coastal Mexico

Vessel design, patterns of surface attrition and sooting, and frequencies of different forms provide the basis for interpretations of the function of ceramic vessels from the Early Formative (1550–850 b.c.) site of Paso de la Amada, on the Pacific Coast of Chiapas, Mexico. Vessels used for the transport, preparation, storage, cooking, and serving of foods and beverages are tentatively identified. Results reveal an assemblage dominated by a few simple forms that were used for a variety of purposes. In particular vessels used for cooking, preparation, and storage appear to have been unspecialized. At the same time, ceramic serving wares-often carefully decorated-form a significant proportion of the assemblage.

Brief communication: first evidence of LSAMAT in non-native Americans: historic Senegalese from west Africa.

To date, the distinctive dental wear pattern known as LSAMAT, or "lingual surface attrition of the maxillary anterior teeth," has been documented in prehistoric samples from Brazil, Panama, and Puerto Rico only. However, new data from a historic Senegalese sample reveals the first example of this wear pattern outside the Americas. The Senegal LSAMAT is present in 45% of 22 adult crania, and is associated with a caries rate of 40% in 38 adults (6.7% of 534 permanent teeth). A correlation between LSAMAT and caries was also observed in the Latin American samples. In these cases, it was hypothesized that LSAMAT was caused by the specialized consumption of an abrasive, high carbohydrate food, such as manioc. Manioc is a common cultigen in Senegal; thus, it may have also caused the African LSAMAT. The chewing of sugar cane could have been an additional, contributing factor.

Surface Attrition of Worsted Fabrics

This paper describes the effects of wear on the geometric roughness and luster of ten worsted fabrics. It goes further to examine how the changes in surface properties affect the subjective evaluation of fabric appearance according to a panel of assessors.

Pottery Function: A Use-Alteration Perspective. By James M. Skibo.

Introduction. Ethnoarchaeology and Experimental Archaeology Defined. Pottery Use-Alteration. The Pottery Use-Alteration Study. Absorbed Residues. Use-Alteration: Surface Attrition. Use-Alteration: Carbon Deposition. Concluding Comments. Index.

媒体撹はん型ミルにおけるチタニアの超微粉砕同時表面処理による超微粒子化過程

Ultra-fine grinding of titania accompanied by simultaneous surface treatment was conducted in a laboratory-scale media agitating mill. The grinding solvent was n-decane, and stearic acid was added to the solvent as the surfactant. Zirconia beads of 0.6mm diameter were used as the grinding media. The effect of grinding time on the characteristics of titania commimuted in the media agitating mill was investigated. The measured characteristics were true density, specific surface area, particle size distribution, crystallite size, crystal lattice distortion and morphology of the comminuted titania. The amount of contamination of the comminuted titania from the grinding media, rotator and mill wall was also measured.Titania became flaky by surface attrition during the initial stage of grinding. Subsequently, the flaky particles were ground into ultra-fine particles. The comminuted titania had low crystal lattice distortion in the order of 10-4 and a small crystallite size of less than 200A after 5 hours of grinding. The true density of the comminuted titania was almost the same as that of intact titania. There was almost no increase in the background intensity in the XRD profile, and the lattice constant of the comminuted titania was kept constant.

Cavitation erosion of substrates in disk drive component cleaning: An exploratory study

The intent in this paper is threefold: to describe the phenomenon of cavitation erosion, and its occurrence and relevance in substrate cleaning using ultrasound in the magnetic data storage device industry; to introduce a novel method, liquid-borne particle counting, that provides a quantitative measure of erosion without the need for direct surface inspection; to establish a fundamental relationship between substrate surface properties, such as surface energy, and its credibility. The paper concludes with recommendations for surface finishes and coatings to minimize surface attrition due to cavitation erosion.

Is “Lingual surface attrition of the maxillary teeth (LSAMAT)” caused by dental erosion?

Is “Lingual surface attrition of the maxillary teeth (LSAMAT)” caused by dental erosion?

More lingual surface attrition of the maxillary anterior teeth in American Indians: prehistoric Panamanians.

Lingual surface attrition of the maxillary anterior teeth (LSA-MAT) has been found in additional prehistoric Latin American Indian skeletons. LSAMAT was first observed in crania from an Archaic Brazilian site. This second finding occurs in teeth from Venado Beach, a late prehistoric site in Panama. LSAMAT is also present in some fragmentary specimens from the Archaic Cerro Mangote site in Panama. LSAMAT at Venado Beach is present in 57% of 28 adult crania. As in the Brazilian study, LSAMAT is associated with a high caries rate (82% of 50 adults; 11.7% of 852 permanent teeth). As first suggested, eating and processing of some type of abrasive carbohydrate food, such as manioc, is the possible cause of LSAMAT. However, other possible causes relating to habitation on or near marine coasts cannot be totally ruled out.

A new dental wear pattern and evidence for high carbohydrate consumption in a Brazilian Archaic skeletal population

AbstractAn apparently new type of dental wear pattern, lingual surface attrition of the maxillary anterior teeth (LSAMAT), has been found in 85% of 46 adult crania from a 3000–4200 BP Archaic site called Corondó near the Atlantic Ocean coast of Brazil. LSAMAT is associated with a high caries rate (60% of 77 adults; 11% of 1,219 permanent teeth) in what on archeologica grounds alone would be considered a mainly meat‐eating population. It is suggested that both LSAMAT and caries resulted from eating some starchy plant like manioc.

Behavior of Aggregate in the Washington Degradation Test

Abstract The variations of the Washington degradation test values with particle sizes and times of agitation were studied on some samples of aggregate. The sand equivalent measuring technique was modified to read fines produced. The study has established that the Washington degradation test is a clay leaching test dependent on surface area of charge. Surface attrition also occurs. A mathematical model is proposed which agrees with the samples considered.

Dynamic Observations of Abrasion/Snagging: A Laboratory Device for the SEM

In a study of the mechanics of surface attrition of fiber assemblies, a device has been designed and fabricated to be used in conjunction with the scanning electron microscope (SEM). It allows the in situ observation of the deformation of the yam and fabric structures in attrition processes, such as the snagging of a knit fabric by a sharp needle point (or a hook) or the abrasion of a fabric by single or multiple macro-asperities. Some preliminary observations obtained with this device are discussed.