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1

Aluminium content of some foods and food products in the USA, with aluminium food additives  

Microsoft Academic Search

The primary objective was to determine the aluminium (Al) content of selected foods and food products in the USA which contain Al as an approved food additive. Intake of Al from the labeled serving size of each food product was calculated. The samples were acid or base digested and analysed for Al using electrothermal atomic absorption spectrometry. Quality control (QC)

Salim M. Saiyed; Robert A. Yokel

2005-01-01

2

Aluminium content of some foods and food products in the USA, with aluminium food additives.  

PubMed

The primary objective was to determine the aluminium (Al) content of selected foods and food products in the USA which contain Al as an approved food additive. Intake of Al from the labeled serving size of each food product was calculated. The samples were acid or base digested and analysed for Al using electrothermal atomic absorption spectrometry. Quality control (QC) samples, with matrices matching the samples, were generated and used to verify the Al determinations. Food product Al content ranged from <1-27,000 mg kg(-1). Cheese in a serving of frozen pizzas had up to 14 mg of Al, from basic sodium aluminium phosphate; whereas the same amount of cheese in a ready-to-eat restaurant pizza provided 0.03-0.09 mg. Many single serving packets of non-dairy creamer had approximately 50-600 mg Al kg(-1) as sodium aluminosilicate, providing up to 1.5 mg Al per serving. Many single serving packets of salt also had sodium aluminosilicate as an additive, but the Al content was less than in single-serving non-dairy creamer packets. Acidic sodium aluminium phosphate was present in many food products, pancakes and waffles. Baking powder, some pancake/waffle mixes and frozen products, and ready-to-eat pancakes provided the most Al of the foods tested; up to 180 mg/serving. Many products provide a significant amount of Al compared to the typical intake of 3-12 mg/day reported from dietary Al studies conducted in many countries. PMID:16019791

Saiyed, Salim M; Yokel, Robert A

2005-03-01

3

Precipitation in aluminium-copper alloys containing germanium additions  

Microsoft Academic Search

Zone formation and ’ precipitation have been studied in an Al 2 at% Cu alloy containing 0·4 at% germanium, or combined additions of 0·4 at% germanium + 0·4 at % magnesium. The germanium addition retards zone formation and enhances ’ precipitation. These effects are explained by assuming that groupings of germanium-solute atoms interact strongly with quenched-in vacancies. The combined addition

G. E. Thompson; B. Noble

1973-01-01

4

Hot-pressing behaviour of silicon carbide powders with additions of aluminium oxide  

Microsoft Academic Search

The hot-pressing behaviour of different silicon carbide powders (average particle sizes ranging from ~ 0.5 to 9 µm) with aluminium oxide additions ranging from 0.01 to 0.15 volume fractions was investigated. Using powders with an average particle size -2 for volume fractions of AI2O3\\u000a$$\\\\bar > $$\\u000a 0.02. A liquid phase forms at high temperatures which dissolves the silicon carbide

F. F. Lange

1975-01-01

5

The reactions of oxidised aluminium surfaces with lubricant additives and related compounds  

NASA Astrophysics Data System (ADS)

To improve the understanding of the role of lubricants in metal deformation processes, FABSIMS (fast atom bombardment secondary ion mass spectroscopy) and RAIRS (reflection absorption infrared spectroscopy) were used to study the chemical interaction of carboxylic acids on oxidised aluminium surfaces. Both techniques detected acid anions, so were consistent with the chemisorption of the acid molecules on the surface. In addition, high mass fragments were detected in the FABSIMS spectra that are associated with oxide clusters and appear to be characteristic of the adsorbed state of the organic acid on the surface. Results from FABSIMS analysis of a sample from a hot rolling mill indicate that similar types of reaction occur in the rolling process.

Treverton, J. A.; Ball, J.; Fairlie, M.

1991-10-01

6

T-phase Precipitation induced by the Addition of Silver to an Aluminium-Copper-Magnesium Alloy  

Microsoft Academic Search

RECENTLY attention has been directed to the effects of small amounts (approximately 0.1 atomic per cent) of silver on the structure and properties of certain age-hardening aluminium alloys, since the changes that occur are thought to have both fundamental and practical significance1-7. As part of this work, a detailed investigation is being made of silver additions to a wide range

J. H. Auld; J. T. Vietz; I. J. Polmear

1966-01-01

7

The use of sodium ?-alumina for controlling the rate of sodium addition to aluminium alloys  

Microsoft Academic Search

Sodium, when added at concentrations of 30–200 ppm, can be used to modify the microstructure and properties of a number of aluminium alloys. This has traditionally been achieved by physically adding a sodium rich alloy or flux to the melt. However, this method suffers from considerable inefficiency since much of the sodium burns or evaporates on the surface of the

G. Doughty; D. J. Fray; C. Van Der Poorten; J. DeKeyser

1996-01-01

8

Improvement in the thermal shock resistance of alumina through the addition of submicron-sized aluminium nitride particles  

Microsoft Academic Search

The possibility of improving the thermal shock behaviour of alumina under mild thermal conditions due to the addition of submicron-sized and homogeneously dispersed AlN particles is studied. Processing conditions were adjusted in order to avoid the formation of AlON and, consequently, a decrease in the thermal conductivity of the composite. To evaluate the thermal shock behaviour, samples containing Vickers indentations

Mar??a Isabel Nieto; Rafael Mart??nez; Leo Mazerolles; Carmen Baud??n

2004-01-01

9

[Research on aluminium content of the diet in haerbin and daily aluminium intake of the local people].  

PubMed

The three sources of dietary aluminium were investigated. IPC was used for measuring aluminium content of individual foods. It was found that aluminium level in natural foods is generally less than 1 ppm, rarely exceeds 10 ppm. Some foods may contain up to 10-30 ppm aluminium during processing and handling. The concentration of aluminium in tape water was usually less than 0.05 ppm. The richest natural sources of aluminium are tea leaves, Chinese prickly ash and mustard. The aluminium content of tea leaves ranges from 300 to 1800 ppm and about 16-20% of the aluminium is extracted from the leaves. Foods made with aluminium-containing food additives contain extremely high level of aluminium. In most cases, the amount of aluminium leaching from aluminium utensils is very small or undetectable except when foods with low pH such as tomatoes are heated in aluminium utensils. Generally 4-15 mg, seldom up to 20 mg aluminium is taken daily from diet by Chinese people. Some people may consume more than 100mg aluminium from diet due to intake of foods made with aluminium-containing food additives. PMID:8325176

Wen, W; Chen, B Q; Li, D

1993-01-01

10

ADDITION  

NSDL National Science Digital Library

Addition can be so much fun, especially with these games. Tweet, Tweet, Addition is not a game for the birds. Keep the game Math Popper away from all sharp pins! Watch out! Addition facts are attacking the spaceships in Addition Attack In Cannon Math you can shoot people out of a cannon! It is great fun!! Dr. Brain s Robot needs help with his math facts. Can you help ...

Games, Aidan'S M.

2010-12-20

11

Microbial interactions with aluminium  

Microsoft Academic Search

Although aluminium is the most abundant metal in the Earth's crust, it lacks biological functions and shows a low bioavailability. Acid rain, however, solubilizes aluminium to toxic levels. Most research on the biological effects of aluminium has been centred on the analysis of aluminium-tolerant plants as well as its possible relationship with neurological disorders in humans. Also, several studies have

Rogelio Garciduefias Pifia; Carlos Cervantes

1996-01-01

12

Addition  

NSDL National Science Digital Library

We will practice adding! Practice with Fribbit! Fribbit Addition Add the numbers to save the apples. Save the Apples! Help the pirate add his marbles. Pirate Marble Addition Catch the correct sum! Fish Addish Balance the sides of the equal sign. Balance Equations ...

Hoffmann, Mrs.

2011-08-09

13

Chelometric determination of aluminium in vaccines*  

PubMed Central

A rapid and accurate chelometric method is described for the determination of aluminium in aluminium-phosphate-adsorbed vaccines. Thiomersal preservative in the vaccine is first destroyed and the aluminium content is determined by addition of excess disodium edetate (Na2-EDTA) and back-titration with zinc sulfate using dithizone as an indicator. Phosphate does not interfere with the method. The aluminium content of the samples under investigation varied from 0.3 mg/ml to 1.0 mg/ml. In analysis of vaccines containing inactivated poliomyelitis virus, aluminium was determined with a standard deviation of 0.0014 mg and in other vaccines with a standard deviation of approximately 0.0040 mg.

Meijerman, G. W.; van Lier, K. L.

1965-01-01

14

Mullite and alumina composites preparation from cordierite and aluminium hydroxide  

SciTech Connect

Densification and phase transformation of mullite and alumina composites prepared from cordierite and aluminium hydroxide mixture were investigated. X-ray diffraction revealed the presence of mullite since the early stage of aluminium hydroxide addition to the cordierite. Above 40 wt.% of aluminium hydroxide addition, the presence of spinel and mullite phases can be detected by X-ray diffraction and confirmed by X-ray photoelectron spectroscopy. The X-ray photoelectron spectroscopy analysis showed that the amounts of spinel as well as mullite present increased with increasing aluminium hydroxide concentration at the expense of cordierite. These analyses were completed by density measurements and scanning electron microscopy observation.

Aklouche, N. [Constantine Ceramics Laboratory, Mentouri University, 25000 Constantine (Algeria)], E-mail: n.aklouche@yahoo.fr; Achour, S. [Constantine Ceramics Laboratory, Mentouri University, 25000 Constantine (Algeria); Tabet, N. [Surface Science Laboratory, Physics Department, KFUPM, 31261 Dhahran (Saudi Arabia)

2008-05-06

15

Detection of aluminium residue in sauces packaged in aluminium pouches  

Microsoft Academic Search

The interactions between food and aluminium packaging can be a potential source of aluminium release which can contribute to aluminium ingestion in the human body. Hence, it is important to identify the possible effects of such an interaction. The purpose of this study was to compare the aluminium content and the pH levels of three different types of sauces, packaged

S. P. Joshi; R. B. Toma; N. Medora; K. O'Connor

2003-01-01

16

Polyaniline Coatings for Aluminium  

NASA Astrophysics Data System (ADS)

Coatings of the emeraldine base (EB) form of polyaniline were investigated as anti-corrosion coatings for aluminium. A very thin layer of polyaniline was deposited from solutions of 1-Methyl-2-Pyrrolidinone (NMP) onto 5005 Al alloy surfaces pretreated in various ways. X-ray Photoelectron Microscopy (XPS) was used to examine the nature of the interaction between the polyaniline coating and the aluminium surface oxide both prior to, and after exposure to moisture in a controlled humidity chamber. A chemical interaction between the polyaniline coating and the surface aluminium oxide takes place, as evidenced by changes in the ratio of reduced/oxidized N in the polyaniline and changes in the oxide/hydroxide ratio of the aluminium oxide, but this varies depending on pre-treatment of Al. On exposure to humidity, the aluminium oxide underneath coatings showed limited growth, while untreated surface oxide layer grew rapidly.

Fujita, Junko; Hyland, Margaret M.

17

Aluminium in Transport  

NSDL National Science Digital Library

A concise fact sheet on aluminum use in transport by the European Aluminium Association (EAA). Topics include applications (auto, air, marine, and rail), benefits, economic role, energy consumption, history, and sustainability.

European Aluminium Association (EAA)

18

Wear behaviour of aluminium matrix composite materials  

Microsoft Academic Search

Wear behaviour of aluminium matrix composites is characterized by the dry spindle wear test under various conditions (volume fractions of reinforcements, sliding distances and speeds). Wear resistance of composites is improved due to the presence of reinforcements, but no noticeable improvements are observed in the wear resistance with more than 20% addition of reinforcements. To analyse wear mechanisms, wear surfaces

C. S. Lee; Y. H. Kim; K. S. Han; T. Lim

1992-01-01

19

Pressure welding of aluminium to copper  

Microsoft Academic Search

Aluminium and copper are two metals commonly used in industrial production. Because of their specific physical properties (high thermal and electrical conductivity, low strength, and good ductility) these metals are regarded as difficult to pressure weld. Pressure welding of them is additionally made more difficult because of the pronounced differences in their respective hardness, electrical conduction, thermal conductivity, and melting

H. Papkala; A. Pietras

2006-01-01

20

Corrosion inhibition of aluminium and zinc pigments by saccharides  

Microsoft Academic Search

Both aluminium and zinc pigments react in aqueous alkaline media (e.g., water-borne paints) with the evolution of hydrogen which can be measured gas volumetrically. The hydrogen corrosion of aluminium pigment can be inhibited with addition of the reducing saccharides fructose and mannose as well as with addition of the reducing ascorbic acid whereas the non-reducing saccharose did not inhibit this

B Müller

2002-01-01

21

Dietary exposure to aluminium of the Hong Kong population.  

PubMed

A total of 256 individual food samples were collected in Hong Kong for aluminium testing. Most of food samples were analysed in ready-to-eat form. High aluminium levels were found in steamed bread/bun/cake (mean: 100-320 mg kg(-1)), some bakery products such as muffin, pancake/waffle, coconut tart and cake (mean: 250, 160, 120 and 91 mg kg(-1), respectively), and jellyfish (ready-to-eat form) (mean: 1200 mg kg(-1)). The results demonstrated that aluminium-containing food additives have been widely used in these food products. The average dietary exposure to aluminium for a 60 kg adult was estimated to be 0.60 mg kg(-1) bw week(-1), which amounted to 60% of the new PTWI established by JECFA. The main dietary source was "steamed bread/bun/cake", which contributed to 60% of the total exposure, followed by "bakery products" and "jellyfish", which contributed to 23 and 10% of the total exposure, respectively. However, the estimation did not include the intake of aluminium from natural food sources, food contact materials or other sources (e.g. drinking water). Although the results indicated that aluminium it is unlikely to cause adverse health effect for the general population, the risk to some populations who regularly consume foods with aluminium-containing food additives cannot be ruled out. PMID:20234962

Wong, Waiky W K; Chung, Stephen W C; Kwong, K P; Yin Ho, Yuk; Xiao, Ying

2010-04-01

22

Ultrasonic Soldering of Aluminium  

Microsoft Academic Search

FOR some years it has been known that it is possible to tin aluminium and its alloys by subjecting their surface to the action of intense ultrasonic vibration at the same time as molten solder is applied1-3 but the mechanism for this effect does not seem to have been studied. We have now established that the process is one of

B. E. Noltingk; E. A. Neppiras

1950-01-01

23

The Constitution of the Aluminium-Rich Aluminium-Cobalt-Copper Alloys, with Special Reference to the Role of Transitional Metals in Alloy Formation  

Microsoft Academic Search

An experimental investigation of aluminium-rich aluminium-cobalt-copper alloys has shown that, as in the alloys of aluminium and copper with nickel and iron respectively, a ternary compound, in addition to the phases Co2Al9 and CuAl2, enters into equilibrium with the primary solid solution. Isothermal sections of the ternary model have been established at 530 degrees and 500 degrees C; the field

P. C. L. Pfeil; G. V. Raynor

1949-01-01

24

Tribological properties of aluminium-based materials  

NASA Astrophysics Data System (ADS)

In order to improve the tribological performance of the aluminium-steel contact, two research lines have been followed: (1) Use of the ordered fluids liquid crystals and ionic liquids as lubricant additives. (2) Tribological behaviour of new powder metallurgy aluminium materials processed by mechanical milling. A parafinic-naftenic base oil modified by a 1wt% of four additives has been used: Three liquid crystals with increasing polarity: 4,4' -dibutylazobenzene (LC1) < colesteryl linoleate (LC2) < n-dodecyl ammonium chloride (LC3), and the ionic liquid 1-ethyl, 3-methyl-imidazolonium tetrafluoroborate. This is the first time that a ionic liquid is studied as lubricant additive. Viscosity measurements at 25 and 100°C, maximum number of molecules by unit aluminium surface and comparative costs of the additives showed the advantage of the ionic additives over the neutral ones. Pin-on-disk tests were performed according to ASTM G99. Influence of load, speed and temperature on friction and wear was studied for each additive. While the ionic liquid gives low friction (<0.1) and wear (?10-5 mm3m-1), the performance of the liquid crystalline additives depends on the conditions. LC3 shows a higher lubricating ability than the neutral LC1 and LC2 under high load, speed or temperature. Only the ionic liquid shows tribochemical interaction (by SEM and EDS) with the steel and aluminium surfaces, with an increment in the fluorine content inside the wear track. The second line was to study the influence of the process conditions on the dry and lubricated wear of new powder-metallurgy aluminium materials. MA Al-NH3 milled under NH3 atmosphere was compared with (MA Al-Air) processed in air and with Al-1 which has not been mechanically alloyed. Conditions for mild to severe wear transition have been established. Al-1 is always under a severe wear regime. MA Al-NH3 shows transition to severe wear at 150°C, showing a 60% reduction in wear rate with respect to MA Al-Air and a two order of magnitude reduction with respect to Al-1. The wear resistance of MA Al-NH3 is attributed to its high hardness, lower porosity, and fine microstructure with submicroscopic reinforcing phases such as aluminium carbide and nitride (by X-ray diffraction and TEM observations).

Iglesias Victoria, Patricia

25

Aluminium contents in baked meats wrapped in aluminium foil  

Microsoft Academic Search

In this investigation, the effect of cooking treatments (60min at 150°C, 40min at 200°C, and 20min at 250°C) on aluminium contents of meats (beef, water buffalo, mutton, chicken and turkey) baked in aluminium foil were evaluated. Cooking increased the aluminium concentration of both the white and red meats. The increase was 89–378% in red meats and 76–215% in poultry. The

Sadettin Turhan

2006-01-01

26

Voids formed from solidifying tin particles in solid aluminium  

Microsoft Academic Search

In this study, voids commonly associated with tin particles in two aluminium alloys containing microalloying additions (0.01 at.%) of tin have been observed by transmission electron microscopy. The voids were generated by quenching the alloys at moderate rates (10–10 K s) from a temperature (718 K) in excess of the melting temperature (501 K) of elemental tin in tin–microalloyed aluminium.

L. Bourgeois; G. Bougaran; J. F. Nie; B. C. Muddle

2010-01-01

27

Aluminium in Commercial Vehicles  

NSDL National Science Digital Library

This manual created by the European Aluminium Association is a comprehensive compilation of aluminum use in commercial applications. Discussed are application, design, joining, treatment, cleaning, repair, and various methods of processing aluminum. Although this report is of particular interest to design engineers, process engineers, repair managers and maintenance managers, itâs also very useful to anyone interested in aluminum development and use in transportation.

Association, European A.

28

Anodic oxidation of aluminium  

Microsoft Academic Search

Key aspects of anodic film growth on aluminium at ambient temperatures in aqueous electrolytes, encompassing barrier- and porous-type films, are described. By direct observation of film sections, incorporating inert marker layers and tracers, in the transmission electron microscope and appropriate analysis, the locations of solid-film growth and electrolyte anion effects can be determined precisely. Thus, during barrier-film formation, at high

G. E. Thompson; Y. Xu; P. Skeldon; K. Shimizu; S. H. Han; G. C. Wood

1987-01-01

29

Cavitation erosion of aluminium alloys  

Microsoft Academic Search

Cast aluminium-silicon, cast aluminium-zinc and mechanically alloyed aluminium alloys were eroded in distilled water using a 20 kHz ultrasonic vibratory device. The erosion was measured by weight loss, and the damaged surface was examined using metallographic and profilometric techniques. The maximum differences in the incubation period, in the linear erosion rate and in the mass loss after a 10 h

W. J. Tomlinson; S. J. Matthews

1994-01-01

30

NEW DEVELOPMENTS IN X-RAY TECHNOLOGICAL CONTROL OF ELECTROLYTE COMPOSITION IN ALUMINIUM PRODUCTION  

Microsoft Academic Search

Electrolyte composition is an important parameter of aluminium production technology. An integral technical characteristic of the composition is cryolite ration (CR) - ratio of molar concentrations of sodium and aluminium fluorides, additional characteristics - concentrations of calcium and magnesium fluoride additions. Keeping these parameters within the optimal technological range is realized with regular addi- tion of fluoride salts to the

I. S. Yakimov; P. S. Dubinin; A. N. Zaloga; O. E. Piksina; S. D. Kirik; S. G. Ruzhnikov; A. F. Shimansky

2009-01-01

31

Wear behaviour of aluminium matrix composite materials  

Microsoft Academic Search

Wear behaviour of aluminium matrix composites is characterized by the dry spindle wear test under various conditions (volume\\u000a fractions of reinforcements, sliding distances and speeds). Wear resistance of composites is improved due to the presence\\u000a of reinforcements, but no noticeable improvements are observed in the wear resistance with more than 20% addition of reinforcements.\\u000a To analyse wear mechanisms, wear surfaces

C. S. Lee; Y. H. Kim; K. S. Han; T. Lim

1992-01-01

32

Polymeric corrosion inhibitors for aluminium pigment  

Microsoft Academic Search

In aqueous alkaline media (e.g. water-borne metallic paints) aluminium pigments react by the evolution of hydrogen. This corrosion reaction can be inhibited by addition of different water-soluble polymers with carboxyl groups like polyacrylic acids, styrene–maleic acid or styrene–acrylate copolymers. As a rough empirical rule can be stated that the corrosion-inhibiting effect of polymers with carboxyl groups increases with decreasing molecular

Bodo Müller

1999-01-01

33

Accumulation of nano-aluminium during combustion of composite solid propellant mixtures  

Microsoft Academic Search

Nano-aluminium particles are produced using the electric wire explosion process in an inert atmosphere at our institute. This\\u000a paper reports the characterization of nanoaluminium particles in combination with other solid propellant ingredients for their\\u000a thermal and combustion behaviour. High-heating-rate hot-stage microscopic experiments are performed with different mixtures\\u000a of propellant ingredients. The effects of addition of nano-aluminium versus micron-sized aluminium in

K. Jayaraman; S. R. Chakravarthy; R. Sarathi

2010-01-01

34

Reformed bamboo\\/glass fabric\\/aluminium composite as an ecomaterial  

Microsoft Academic Search

A super-hybrid (natural composite\\/fibre-reinforced composite\\/metal hybridization) ecomaterial, reformed bamboo\\/glass fabric\\/aluminium (RB\\/GF\\/Al) was developed. The addition of a sparse glass fabric\\/epoxy resin layer between reformed bamboo and aluminium proved to be effective in increasing the compressive, tensile strength of the composite material. In particular, the interfacial shear strength between the reformed bamboo and aluminium was improved, and was the transverse tensile

S. H. LI; J. R De Wijn; K De Groot; Q. Y Zeng; B. L Zhou

1998-01-01

35

Automotive Trends in Aluminium - The European Perspective  

Microsoft Academic Search

The recent developments in aluminium application in the European automotive industry are presented and trends in average and specific use of aluminium in passenger cars is analyzed. Aspects of material selection and innovative concepts of car construction using aluminium that help to meet economical and environmental requirements as well as demands for enhanced driving comfort are discussed. Aluminium alloys developed

J. Hirsch

2004-01-01

36

Low temperature thermal properties of vitreous silica and plastically deformed pure aluminium  

Microsoft Academic Search

The thermal conductivity, heat capacity and heat release of vitreous silica and pure plastically deformed aluminium were investigated. The temperature dependence and absolute value of the lattice thermal conductivity of both materials are very similar. However, in contrast to vitreous silica neither long-time heat release nor additional contribution to the heat capacity expected for tunnelling systems was found for aluminium.

S. Sahling; S. Abens

2001-01-01

37

Recycling of aluminium swarf by direct incorporation in aluminium melts  

Microsoft Academic Search

The purpose of this work was to recover a standard AlSi12Cu1 alloy from machining chips inside the foundry plant, by using an environmentally friend technique to produce cast ingots with characteristics similar to those of the commercially available 2nd melt raw material.The recyclability of aluminium swarf using different melting techniques and the influence of chips preparation in the aluminium alloy

H. Puga; J. Barbosa; D. Soares; F. Silva; S. Ribeiro

2009-01-01

38

Soldering of aluminium with copper  

Microsoft Academic Search

Soldering of aluminium with copper becomes more significant, because of relatively low process temperature of about 400–450°C. It is applied not only in electrotechnical industry, in joining Al–Cu conductors, but also in cooling and air-conditioning equipment and in solar construction of collectors (Winiowski A. Lutowanie twarde aluminium i jegostopów – nowe trendy technologiczne, Biuletyn Instytutu Spawalnictwa, nr 6\\/2000, Fontargen GmbH.

Zbigniew Mirski; Kazimierz Granat; Hubert Drzeniek; Tomasz Piwowarczyk; Tomasz Wojdat

2011-01-01

39

Availability of aluminium from tea and coffee  

Microsoft Academic Search

The amount of aluminium in different kinds of tea and ground coffee was analysed, the transfer of aluminium into the infusion\\u000a was determined and aluminium intake via tea and coffee was calculated within the framework of our investigations. Aluminium\\u000a concentrations amounted to (in ?g\\/g dry matter): black tea, 899; flavoured black tea, 763; peppermint tea, 477; mountain herbal\\u000a tea, 419;

Mario Müller; M. Anke; Heike Illing-Günther

1997-01-01

40

Aluminium phosphide-induced leukopenia.  

PubMed

Acute intoxication from the pesticide aluminium phosphide is a relatively rare, life-threatening condition in which cardiovascular decompensation is the most feared problem. We report the case of a patient exposed to aluminium phosphide-liberated phosphine gas. It resulted in the development of a gastroenteritis-like syndrome accompanied by severe reduction in white blood cell numbers as an early and prominent manifestation. By affecting important physiological processes such as mitochondrial function and reactive oxygen species homeostasis, phosphine could cause severe toxicity. After presenting the characteristics of certain leucocyte subpopulations we provide the current molecular understanding of the observed leukopenia which in part seems paradoxical. PMID:24172776

Ntelios, Dimitrios; Mandros, Charalampos; Potolidis, Evangelos; Fanourgiakis, Panagiotis

2013-10-30

41

Triaxial compression of aluminium foams  

Microsoft Academic Search

Triaxial compressive tests have been conducted on CYMAT closed-cell aluminium foams of five different relative densities to investigate their initial failure surfaces under multiaxial loading. Quasi-static uniaxial compressive and tensile tests have also been performed to obtain their uniaxial strength. The experimentally measured yield surfaces are compared with various published phenomenological yield surface models. Reasonable agreement has been observed when

D. Ruan; G. Lu; L. S. Ong; B. Wang

2007-01-01

42

Crack growth in aluminium cylinders  

Microsoft Academic Search

Some common portable aluminium gas cylinders have shown a tendency to develop cracking. This cracking has in some cases led to leaks and on occasions to violent and sometimes fatal failures. There are a number of features of this cracking which have not been explained properly.Previous estimates of the growth rate of these cracks under sustained load have been developed

J. W. H. Price; R. N. Ibrahim

2000-01-01

43

Aluminium Gettering in Silicon Wafers  

NASA Astrophysics Data System (ADS)

The effect of an evaporated thick aluminium paper on electrical properties of multicrystalline and gold contaminated FZ monocrystalline silicon wafers was investigated. By means of minority carrier diffusion length measurements and Deep Level Transient Spectroscopy, it was deduced that the material improvements observed after annealing at 900°C are due to gettering of metallic impurities in the Al-Si alloyed layer.

Martinuzzi, S.; Porre, O.; Périchaud, I.; Pasquinelli, M.

1995-09-01

44

Environmental evaluation of aluminium cans for beverages in the German context  

Microsoft Academic Search

Background  In the years 2000 and 2002, the German Environment Agency in Berlin (UBA) published the results of a comprehensive LCA study\\u000a on beverage containers comprising aluminium cans with volumes of 330 ml and 500 ml. Starting with the aluminium can scenarios\\u000a and the respective results obtained during the UBA study, additional analyses were performed by IFEU in 2003, a German consultant\\u000a having

Andreas Detzel; Jonas Mönckert

2009-01-01

45

Ultrasonic butt welding of aluminium, anticorrosive aluminium and copper plate specimens  

Microsoft Academic Search

Ultrasonic butt welding of thick metal plate specimens is studied. Welding specimens used are aluminium, anticorrosive aluminium, and copper plates of 6-mm thickness. These welding specimens are successfully joined end to end with specimen strength of about 100 MPa (pure aluminium) or 250 MPa (anticorrosive aluminium) using 26-kHz or 19-kHz butt welding equipment. An ultrasonic vibration source of 19 kHz

Jiromaru TSUJINO; Tetsugi UEOKA

1988-01-01

46

Recycling und Werkstoffentwicklung von Aluminium  

Microsoft Academic Search

\\u000a Summary  Current research at the Institute of Nonferrous Metallurgy, University of Leoben, with the main focus aluminium technology,\\u000a covers a wide scope of topics, ranging from field production and product optimisation to issues concerning secondary metallurgy\\u000a as well as residual material reconditioning. In collaboration with research and industry partners from different branches,\\u000a issues of castability and workability, heat treatment, machining, high

H. Antrekowitsch; S. Koch; H. Paulitsch; S. Pogatscher; P. Pucher; F. Stadler; C. Wagner

2011-01-01

47

Interfacial morphology of low-voltage anodic aluminium oxide  

SciTech Connect

X-ray reflectivity (XRR) and neutron reflectivity (NR), as well as ultra-smallangle X-ray scattering (USAXS), are used to examine the in-plane and surfacenormal structure of anodic films formed on aluminium alloy AA2024 and pure aluminium. Aluminium and alloy films up to 3500 A thick were deposited on Si wafers by electron beam evaporation of ingots. Porous anodic aluminium oxide (AAO) films are formed by polarizing at constant voltage up to 20 V noble to the open circuit potential. The voltage sweet spot (5 V) appropriate for constant-voltage anodization of such thin films was determined for both alloy and pure Al. In addition, a new concurrent voltage- and current-control protocol was developed to prepare films with larger pores (voltages higher than 5 V), but formed at a controlled current so that pore growth is slow enough to avoid stripping the aluminium substrate layer. USAXS shows that the pore size and interpore spacing are fixed in the first 10 s after initiation of anodization. Pores then grow linearly in time, at constant radius and interpore spacing. Using a combination of XRR and NR, the film density and degree of hydration of the films were determined from the ratio of scattering length densities. Assuming a chemical formula Al2O3xH2O, it was found that x varies from 0.29 for the native oxide to 1.29 for AAO grown at 20 V under concurrent voltage and current control. The average AAO film density of the porous film at the air surface is 2.45 (20) g cm3. The density of the barrier layer at the metal interface is 2.9 (4) g cm3, which indicates that this layer is also quite porous

Hu, Naiping [University of Cincinnati; Dongcinn, Xuecheng [University of Cincinnati; He, Xueying [University of Cincinnati; Argekar, Sandip [University of Cincinnati; Zhang, Yan [University of Cincinnati; Browning, Jim [ORNL; Schaefer, Dale [University of Cincinnati

2013-01-01

48

Shear Strength of Single Lap Joint Aluminium-Thermoplastic Natural Rubber (Al-TPNR) Laminated Composite  

NASA Astrophysics Data System (ADS)

In this work, we studied the effect of surface treatment on the aluminium surface and a coupling agent to improve adhesion between aluminium with organic polymer. Thermoplastic natural rubber (TPNR) matrix was prepared by melt blending of natural rubber (NR), liquid natural rubber (LNR) compatibilizer, linear low density polyethylene (LLDPE) and polyethylene grafted maleic anhydride (PE-g-MAH). The PEgMAH concentration used was varied from 0% - 25%. In addition, the aluminium surface was pre-treated with 3-glycidoxy propyl trimethoxy silane (3-GPS) to enhance the mechanical properties of laminated composite. It was found that the shear strength of single lap joint Al-TPNR laminated composite showing an increasing trend as a function of PE-g-MAH contents for the 3-GPS surface treated aluminium. Moreover, the scanning electron microscope (SEM) revealed that the strength improvement was associated with the chemical state of the compound involved.

Muzakkar, M. Z.; Ahmad, S.; Yarmo, M. A.; Jalar, A.; Bijarimi, M.

2013-04-01

49

Aluminium migration to orange juice in laminated paperboard packages  

Microsoft Academic Search

The migration of aluminium (Al) from aseptic laminated paperboard packages was studied by monitoring the Al content of orange juice (plain juice, no additives) filled into such packages and stored at ambient temperature (23°C) for up to 1 year. Analytical procedure includes MW-assisted digestion of orange juice with concentrated nitric acid followed by determination of Al concentration by double-focusing sector

Ilia Rodushkin; Astrid Magnusson

2005-01-01

50

Surface characterization of thin layers of aluminium oxide  

Microsoft Academic Search

Thin oxide layers of commercial pure aluminium (1100-Al) and AlZnMgCu alloy (7075-Al) were characterized after oxidation in a 2.45 GHz microwave discharge in oxygen plasma at low temperature (400 ± 50 °C). The composition and structure of the oxide layers were studied by Auger electron spectroscopy (AES) and Fourier transform IR (FTIR) spectroscopy. In addition, atomic force microscopy (AFM) and

A. Raveh; Z. K. Tsameret; E. Grossman

1997-01-01

51

Melt spun aluminium alloys for moulding optics  

NASA Astrophysics Data System (ADS)

Melt spinning is a rapid quenching process that makes it possible to create materials with a very fine microstructure. Due to this very fine microstructure the melt spinning process is an enabler for diamond turning optics and moulds without the need of post-polishing. Using diamond turning of melt spun aluminium one can achieve <=2 nm Rq surface roughness. Application areas are imaging and projection optics, mirrors, moulds for contact lenses and spectacles. One of the alloys that RSP produces is RSA-905. This alloy has a solid track record as a better and cheaper concept in the application of moulds for optical components such as contact lenses. The RSA-905 is a dispersion hardened amorphous-like alloy that keeps its properties when exposed to elevated temperatures (up to 380°C). This gives the material unique features for optics moulding applications. RSA-905 moulds are cheaper and better than traditional mould concepts such as copper or brass with or without NiP plating. In addition logistics can be simplified significantly: from typical weeks-months into days-week. Lifetime is typically in the range of 100.000 - 200.000 shots. For high volume production typically ranging from several 100.000 - several 1.000.000 shots, NiP plated steel moulds are typically used. By using an appropriate optical coating concept RSA-905 can be upgraded to a competitive alternative to steel in terms of price, performance and logistics. This paper presents some recent developments for improved mould performance of such concept. Hardness, wear resistance and adhesion are topics of interest and they can be applied by special coatings such as diamond-like carbon (DLC) and chromium nitride (CrN). These coatings make the aluminium alloy suitable for moulding mass production of small as well as larger optics, such as spectacle lenses.

Gubbels, G.; Tegelaers, L.; Senden, R.

2013-09-01

52

Production of ?-alumina from waste aluminium dross  

Microsoft Academic Search

Processing of aluminium dross is one of the most challenging tasks because of its toxic nature. The dross generated while melting at various facilities is generally remelted with salts to recover residual metal values. The remaining residue dross contains mostly aluminium oxide, alloying elements and salts such as NaCl or KCl. This residue dross while stock piling creates pollution of

B. R. Das; B. Dash; B. C. Tripathy; I. N. Bhattacharya; S. C. Das

2007-01-01

53

Microcracks in aluminium alloys developed in the cleaning action region  

Microsoft Academic Search

Microcracks developed in the cleaning action region during the GTA (TIG) process have been investigated using aluminium and aluminium alloys. Although no microcracks are found in pure aluminium and commercially pure aluminium, microcracks are mainly developed in Al?Mg alloys where the oxide film is ruptured by the cleaning action. The microcracking trend found is analogous to the weld solidification crack

M. Katoh; K. Nishio; T. Yamaguchi; S. Mukae

1995-01-01

54

Acid dissolution of alumina from waste aluminium dross  

Microsoft Academic Search

Aluminium and its chemicals are generally produced from its oxidic ores, mainly bauxite through NaOH leaching by Bayer's process. There are other oxidic raw materials such as coal ash, clay etc. which are being explored with little success.Aluminium dross formed while melting of aluminium in presence of air is recycled back to the smelter to recover the residual aluminium after

B. Dash; B. R. Das; B. C. Tripathy; I. N. Bhattacharya; S. C. Das

2008-01-01

55

Recycling of aluminium scrap for secondary Al-Si alloys.  

PubMed

An increasing amount of recycled aluminium is going into the production of aluminium alloy used for automotive applications. In these applications, it is necessary to control and remove alloy impurities and inclusions. Cleaning and fluxing processes are widely used during processing of the alloys for removal of inclusions, hydrogen and excess of magnesium. These processes use salt fluxes based in the system NaCl-KCl, injection of chlorine or mixture of chlorine with an inert gas. The new systems include a graphite wand and a circulation device to force convection in the melt and permit the bubbling and dispersion of reactive and cleaning agents. This paper discusses the recycling of aluminium alloys in rotary and reverberatory industrial furnaces. It focuses on the removal of magnesium during the melting process. In rotary furnaces, the magnesium lost is mainly due to the oxidation process at high temperatures. The magnesium removal is carried out by the reaction between chlorine and magnesium, with its efficiency associated to kinetic factors such as concentration of magnesium, mixing, and temperature. These factors are also related to emissions generated during the demagging process. Improvements in the metallic yield can be reached in rotary furnaces if the process starts with a proper salt, with limits of addition, and avoiding long holding times. To improve throughput in reverberatories, start the charging with high magnesium content material and inject chlorine gas if the molten metal is at the right temperature. Removal of magnesium through modern technologies can be efficiently performed to prevent environmental problems. PMID:20837560

Velasco, Eulogio; Nino, Jose

2010-09-13

56

The inhibition of aluminium corrosion in potassium hydroxide by “Congo Red” dye, and synergistic action with halide ions  

Microsoft Academic Search

Purpose – To investigate the inhibitive effect of Congo red dye (CR) for aluminium corrosion in strong alkaline solutions and evaluate the synergistic effect of halide ions on the inhibition efficiency. Design\\/methodology\\/approach – Corrosion rates of aluminium test coupons were determined by gravimetric technique at 30 and 60°C. Inhibition efficiencies of the additives (0.01-5.0 mM CR and 5.0 mM CR+0.5

E. E. Oguzie; G. N. Onuoha; A. I. Onuchukwu

2005-01-01

57

A technique for obtaining thin foils of aluminium and aluminium alloys for transmission electron metallography  

Microsoft Academic Search

The structural changes produced by ageing aluminium-copper and aluminium-magnesium-zinc-copper alloys have been investigated by examining foils of these alloys in the electron microscope. The foils have been obtained by mechanical reduction in thickness followed by controlled electropolishing and chemical dissolution of the remaining oxide film.

R. B. Nicholson; G. Thomas; J. Nutting

1958-01-01

58

Steel cathodic protection afforded by zinc, aluminium and zinc\\/aluminium alloy coatings in the atmosphere  

Microsoft Academic Search

Zinc has traditionally been the metallic material most widely used to protect steel against atmospheric corrosion due to its ability to afford cathodic protection to steel in all types of natural atmospheres. In recent decades, aluminium and zinc\\/aluminium alloy coatings have been used instead of zinc in certain atmospheric applications. Although these coatings present some advantages over zinc, they are

Z. Panossian; L. Mariaca; M. Morcillo; S. Flores; J. Rocha; J. J. Peña; F. Herrera; F. Corvo; M. Sanchez; O. T. Rincon; G. Pridybailo; J. Simancas

2005-01-01

59

Recuperative aluminium recycling plant. A demonstration at J. McIntyre (Aluminium) Ltd. (Nottingham (GB)).  

National Technical Information Service (NTIS)

Direct energy savings worth up to 470,000 pounds/year are being achieved by J McIntyre (Aluminium) Ltd in the United Kingdom as a result of the development of a recuperative aluminium recycling plant. The overall design incorporates a novel version of a c...

1991-01-01

60

Structural engineering of nanoporous anodic aluminium oxide by pulse anodization of aluminium  

Microsoft Academic Search

Nanoporous anodic aluminium oxide has traditionally been made in one of two ways: mild anodization or hard anodization. The first method produces self-ordered pore structures, but it is slow and only works for a narrow range of processing conditions; the second method, which is widely used in the aluminium industry, is faster, but it produces films with disordered pore structures.

Kathrin Schwirn; Martin Steinhart; Eckhard Pippel; Roland Scholz; Ulrich Gösele; Woo Lee

2008-01-01

61

Severe cerebral congophilic angiopathy coincident with increased brain aluminium in a resident of Camelford, Cornwall, UK  

PubMed Central

In July 1988, 20?tonnes of aluminium sulphate was discharged by the South West Water Authority into the drinking water supplied to a large region of North Cornwall. Up to 20?000 people were exposed to concentrations of aluminium which were 500–3000 times the acceptable limit under European Union legislation (0.200?mg/l). Although this incident is currently the topic of a government inquiry, nothing is known about its longer?term repercussions on human health. The first neuropathological examination of a person who was exposed and died of an unspecified neurological condition was carried out. A rare form of sporadic early?onset ? amyloid angiopathy in cerebral cortical and leptomeningeal vessels, and in leptomeningeal vessels over the cerebellum was identified. In addition, high concentrations of aluminium were found coincident with the severely affected regions of the cortex. Although the presence of aluminium is highly unlikely to be adventitious, determining its role in the observed neuropathology is impossible. A clearer understanding of aluminium's role in this rare form of Alzheimer's related disease should be provided by future research on other people from the exposed population as well as similar neuropathologies in people within or outside this group.

Exley, C; Esiri, M M

2006-01-01

62

Surface modification for aluminium pigment inhibition.  

PubMed

This review concerns surface treatment of aluminium pigments for use in water borne coatings. Aluminium pigments are commonly used in coatings to give a silvery and shiny lustre to the substrate. Such paints and inks have traditionally been solvent borne, since aluminium pigment particles react with water. For environmental and health reasons solvent borne coatings are being replaced by water borne and the aluminium pigments then need to be surface modified in order to stand exposure to water. This process is called inhibition and both organic and inorganic substances are used as inhibiting agents. The organic inhibiting agents range from low molecular weight substances, such as phenols and aromatic acids, via surfactants, in particular alkyl phosphates and other anionic amphiphiles, to high molecular weight compounds, such as polyelectrolytes. A common denominator for them all is that they contain a functional group that interacts specifically with aluminium at the surface. A particularly strong interaction is obtained if the inhibiting agent contains functional groups that form chelating complex with surface Al(III). Encapsulation of the pigment can be made by in situ polymerization at the surface of the pigment and a recent approach is to have the polymerization occur within a double layer of adsorbed surfactant. The inorganic route is dominated by coating with silica, and recent progress has been made using an alkoxide, such as tetraethoxysilane as silica precursor. Such silica coated aluminium pigments are comparable in performance to chromate inhibited pigments and thus offer a possible heavy metal-free alternative. There are obvious connections between surface modifications made to prevent the pigment to react with water and inhibition of corrosion of macroscopic aluminium surfaces. PMID:17239333

Karlsson, Philip; Palmqvist, Anders E C; Holmberg, Krister

2007-01-18

63

Complexometric determination of aluminium in iron ore, sinter, concentrates and agglomerates.  

PubMed

A method for the complexometric determination of aluminium in iron ore, sinter, concentrates and agglomerates encountered in international trade is described. The sample is fused in a zirconium crucible with a mixed flux of sodium carbonate and sodium peroxide. The fused mass is completely soluble in hydrochloric acid. The R(2)O(3) oxides are then precipitated with ammonia and redissolved in hydrochloric acid. Elements such as iron, titanium and zirconium are separated from aluminium by solvent extraction with cupferron and chloroform. After removal of traces of organic matter from the aqueous phase, the solution is treated with an excess of EDTA, which is then back-titrated with zinc solution (Xylenol Orange as indicator). Addition of ammonium fluoride then releases EDTA equivalent to the aluminium and this is titrated with zinc solution. The method is rapid. The precision and accuracy are excellent, and the results comparable with those obtained by the referee method. PMID:18962398

Bhargava, O P

1979-02-01

64

Self-Pierce Riveting of Three Aluminium Alloy and Mild Steel Sheets  

NASA Astrophysics Data System (ADS)

Three aluminium alloy and steel sheets were joined with a self-piercing rivet. Self-pierce riveting has the function of joining steel and aluminium alloys having very different melting points due to plastic joining. The requisites for joining the three sheets are the driving of the rivet leg through the middle sheet, the flaring of the rivet leg in the lower sheet and the prevention of the fracture of the lower sheet. The joinability for various combinations of the three sheets was determined. When the rivet leg is small, no driving through the middle sheet occurs, the lower sheet ruptures for a large rivet leg. In addition, 980 MPa high strength steel, mild steel and aluminium alloy sheets were joined by the self-pierce riveting.

Mori, K.; Abe, Y.; Kato, T.; Sakai, S.

2010-06-01

65

Aluminium in parenteral nutrition: a systematic review.  

PubMed

Aluminium (Al) toxicity problem in parenteral nutrition solutions (PNS) is decades old and is still unresolved. The aim of this review is to gather updated information about this matter, regarding legislation, manifestations, diagnostics and treatment, patient population at risk and the actions to be taken to limit its accumulation. A structured search using MeSH vocabulary and Title/Abstract searches was conducted in PubMed (http://www.pubmed.gov) up to November 2012. Al is ubiquitous, facilitating its potential for exposure. Nevertheless, humans have several mechanisms to prevent significant absorption and to aid its elimination; therefore, the vast majority of the population is not at risk for Al toxicity. However, when protective gastrointestinal mechanisms are bypassed (for example, parenteral fluids), renal function is impaired (for example, adult patients with renal compromise and neonates) or exposure is high (for example, long-term PNS), Al is prone to accumulate in the body, including manifestations such as impaired neurological development, Alzheimer's disease, metabolic bone disease, dyslipemia and even genotoxic activity. A high Al content in PNS is largely the result of three parenteral nutrient additives: calcium gluconate, inorganic phosphates and cysteine hydrochloride. Despite the legislative efforts, some factors make difficult to comply with the rule and, therefore, to limit the Al toxicity. Unfortunately, manufacturers have not universally changed their processes to obtain a lower Al content of parenteral drug products (PDP). In addition, the imprecise information provided by PDP labels and the high lot-to-lot variation make the prediction of Al content rather inaccurate. PMID:23403874

Hernández-Sánchez, A; Tejada-González, P; Arteta-Jiménez, M

2013-02-13

66

Advantages of Aluminium Hydroxide Adsorbed Combined Diphtheria, Tetanus, and Pertussis Vaccines for the Immunization of Infants  

Microsoft Academic Search

Three combined triple antigen vaccines were used to inoculate infants receiving primary immunization at 3 to 6 months of age. Laboratory potency and toxicity tests and clinical evaluation again showed that the mouse weight gain test is able to predict which vaccines will give reactions in children. The addition of aluminium hydroxide to the vaccine both increased potency and reduced

N. R. Butler; M. A. Voyce; W. L. Burland; Marjorie L. Hilton

1969-01-01

67

Effect of sulphate and molybdate ions on pitting corrosion of aluminium by using electrochemical noise analysis  

Microsoft Academic Search

The effects of sulphate and molybdate ion additives on the pitting corrosion of pure aluminium were investigated as a function of anion concentration by using potentiodynamic polarisation experiment and electrochemical noise measurement. The cumulative probability determined from shot-noise theory was quantitatively analysed by using the Weibull distribution function based upon a stochastic theory. From the statistical variation in the frequency

Kyung-Hwan Na; Su-Il Pyun

2006-01-01

68

Investigation of the growth processes of coatings formed by AC plasma electrolytic oxidation of aluminium  

Microsoft Academic Search

The formation of alumina-based coatings on aluminium by AC plasma electrolytic oxidation (PEO) has been investigated using a silicate electrolyte with selective additions of fine zirconia particles. The coatings comprised an amorphous barrier layer, a relatively dense intermediate layer and a more porous outer layer that contained silicon species. Zirconia was incorporated non-uniformly into the outer layer and, to a

E. Matykina; R. Arrabal; P. Skeldon; G. E. Thompson

2009-01-01

69

Incorporation of zirconia into coatings formed by DC plasma electrolytic oxidation of aluminium in nanoparticle suspensions  

Microsoft Academic Search

A study has been carried out to investigate the incorporation of zirconia into alumina-based coatings formed on aluminium using DC plasma electrolytic oxidation in phosphate and silicate electrolytes containing zirconia nanoparticles in suspension. The nanoparticles were incorporated mainly near the coating surface and within cavities inside the coatings. Additionally, a silicon-rich, surface deposit appeared to entrain the nanoparticles of the

E. Matykina; R. Arrabal; F. Monfort; P. Skeldon; G. E. Thompson

2008-01-01

70

Corrosion inhibition of aluminium in acidic and alkaline media by Sansevieria trifasciata extract  

Microsoft Academic Search

The inhibitive action of leaf extracts of Sansevieria trifasciata on aluminium corrosion in 2M HCl and 2M KOH solutions was studied using the gasometric technique. The results indicate that the extract functioned as a good inhibitor in both environments and inhibition efficiency increased with concentration. Synergistic effects increased the inhibition efficiency in the presence of halide additives. Temperature studies revealed

E. E. Oguzie

2007-01-01

71

Mechanism of seizure of aluminium-silicon alloys dry sliding against steel  

Microsoft Academic Search

A steel ball was slid on aluminium-silicon alloys at different temperatures. After the coefficient of friction had been measured, the surface shear stress was deconvoluted using a two-term model of friction. The ratio of surface shear stress to bulk hardness was calculated as a function of temperature, silicon content and alloying additions. These results are qualitatively similar to those recorded

A. Somi Reddy; B. N. Pramila Bai; K. S. S. Murthy; S. K. Biswas

1995-01-01

72

Identifying Surface Angled Cracks on Aluminium Bar Using Emats and Automated Computer System  

Microsoft Academic Search

Electromagnetic acoustic transducers (EMATs) have been used to generate and detect Rayleigh waves in order to identify surface cracking in aluminium bars and rails. B-scans produced during scans of samples were used to determine the presence of surface defects. Additionally, the differences between signal enhancements due to wave interference at the crack produced by normal (90°) and angled cracks in

M. H. Rosli; R. S. Edwards; B. Dutton; C. G. Johnson; P. T. Cattani

2010-01-01

73

IDENTIFYING SURFACE ANGLED CRACKS ON ALUMINIUM BAR USING EMATS AND AUTOMATED COMPUTER SYSTEM  

Microsoft Academic Search

Electromagnetic acoustic transducers (EMATs) have been used to generate and detect Rayleigh waves in order to identify surface cracking in aluminium bars and rails. B-scans produced during scans of samples were used to determine the presence of surface defects. Additionally, the differences between signal enhancements due to wave interference at the crack produced by normal (90°) and angled cracks in

M. H. Rosli; R. S. Edwards; B. Dutton; C. G. Johnson; P. T. Cattani

2010-01-01

74

Ultrasonic welding of heat-treatable aluminium alloy A6061 sheet  

Microsoft Academic Search

In this study, the authors applied the ultrasonic welding method to weld A6061 heat treatable aluminium alloy and investigated the effects of clamping load and welding time on the properties of the weld. In addition, in order to improve the strength of the joint, the effectiveness of the ethanol droplet on the faying surface was examined. The following results were

Takehiko Watanabe; Hajime Itoh; A. Yanagisawa; Makoto Hiraishi

2009-01-01

75

Effect of welding processes on AA2219 aluminium alloy joint properties  

Microsoft Academic Search

AA2219 aluminium alloy square butt joints without filler metal addition were fabricated using gas tungsten arc welding (GTAW), electron beam welding (EBW) and friction stir welding (FSW) processes. The effects of three welding processes on the tensile, fatigue and corrosion behaviour were studied. Microstructure analysis was carried out using optical and electron microscopes. The results show that the FSW joints

S. MALARVIZHI; V. BALASUBRAMANIAN

2011-01-01

76

Micro Pollutants in Red Mud Waste of Aluminium Plant  

Microsoft Academic Search

The growth of the aluminium industry in India, the process details of an aluminium plant, and the genesis of red mud during the aluminium production have been described. Chemical analysis of a number of red mud samples collected at different points in the red mud ponds, at different periods, have been carried out, and the concentrations of the micro pollutants

C. B. Patel; V. K. Jain; G. S. Pandey

1986-01-01

77

9. Determination of aluminium species in natural waters  

Microsoft Academic Search

The use of aluminium by man is continuously growing and therefore living organisms have to contend with an ever increasing environmental exposure to elevated levels and to unnatural forms or species of this element [l].The potential toxicity of aluminium has become a major medical and environmental issue. For a long time, aluminium was not considered to be toxic to human

B. Fairman; A. Sanz-Medel

1995-01-01

78

Aluminium and iron in the brain—prospects for chelation  

Microsoft Academic Search

Aluminium and iron both accumulate in the brain in the course of ageing. We first briefly review how aluminium may interfere with iron metabolism through its interaction with iron homeostatic mechanisms. Then we present comparative data on the chelation of brain aluminium and iron in appropriate animal models of loading with the two metals. With both desferrioxamine (DFO) B and

Robert R Crichton; Anne Florence; Roberta J Ward

2002-01-01

79

Aluminium ring pulls: an invisible foreign body.  

PubMed Central

The aluminium ring pulls associated with the latest designs of drinks cans can be relatively easily detached from their mounting on the top of the can and subsequently aspirated. Their small size predisposes them to lodge as foreign bodies (FBs) in the throat. The similarity of atomic number between soft tissue (7.5) and aluminium (13) makes detection of these FBs difficult on soft tissue radiography. If aspiration is suspected direct visualization and removal may be indicated even if radiography is negative. Images Fig. 1 Fig. 2 Fig. 3

Stewart, G D; Lakshmi, M V; Jackson, A

1994-01-01

80

Electrodeposition of aluminium and aluminium\\/platinum alloys from AlCl 3 \\/benzyltrimethylammonium chloride room temperature ionic liquids  

Microsoft Academic Search

This paper shows that aluminium and aluminium\\/platinum alloys can be deposited from room temperature ionic liquids formed from an adduct of aluminium trichloride with benzyltrimethyl ammonium chloride. The advantages of this ionic liquid over the majority of those previously investigated is that it is less water sensitive, easier to purify and form and significantly more cost effective. Voltammetry and chronoamperometry

Andrew P. Abbott; Christopher A. Eardley; Nicola R. S. Farley; Gerald A. Griffith; Allin Pratt

2001-01-01

81

Corrosion behavior of aluminium composite coatings  

SciTech Connect

The corrosion behavior of metal-matrix composite (MMC) coatings (3 mm to 5 mm [0.12 in. to 0.2 in.] thick) fabricated by the plasma-transferred arc (PTA) surfacing process was investigated by potentiostatic and immersion techniques. The test electrolyte was a 3.5 wt% sodium chloride (NaCl) solution. Composites were reinforced with angular particles of aluminum oxide (Al{sub 2}O{sub 3}), silicon carbide (SiC), or titanium carbide (TiC) of varying volume fractions (V{sub f} {approx} 2.5% to 40%) and of two sizes (70 {micro}m and 140 {micro}m). The matrix was predominantly aluminium with 2 wt% Ni, which was added to enhance the matrix`s wear resistance. The reinforcement type significantly influenced corrosion behavior of the MMC coatings. The immersion study showed the corrosion rate increased in the following order of reinforcement addition: Al{sub 2}O{sub 3} < SiC < TiC. Al{sub 2}O{sub 3} particles appeared to play no role in the corrosion process, whereas SiC and TiC particles participated actively. Reinforcement surface area appeared to be a significant parameter influencing the corrosion mechanism of the SiC- and TiC-reinforced composites. An increase in V{sub f} generally resulted in a higher corrosion rate for the SiC- and TiC-reinforced composites. Coating porosity, electrical conductivity of the reinforcement, and the presence of nickel aluminide (NiAl{sub 3}, formed during the surfacing process) all influenced corrosion behavior.

Deuis, R.L.; Green, L.; Subramanian, C. [Univ. of South Australia (Australia). Ian Wark Research Inst.; Yellup, J.M. [Commonwealth Scientific and Industrial Research Organization (Australia). Div. of Mfg. Technology

1997-11-01

82

Aluminium, carbonyls and cytokines in human nipple aspirate fluids: Possible relationship between inflammation, oxidative stress and breast cancer microenvironment.  

PubMed

The human breast is likely exposed to Al (aluminium) from many sources including diet and personal care products. Underarm applications of aluminium salt-based antiperspirant provide a possible long-term source of exposure, especially after underarm applications to shaved and abraded skin. Al research in breast fluids likely reflects the intraductal microenvironment. We found increased levels of aluminium in noninvasively collected nipple aspirate fluids (NAF) from 19 breast cancer patients compared with 16 healthy control subjects (268 vs 131?g/l, respectively; p<0.0001). In the same NAF samples we found significantly increased levels of protein oxidative carbonyls in cancer patients compared to healthy women (2.35 vs 0.41nmol/mg prot, respectively; p<0.0001). Aluminium content and carbonyl levels showed a significant positive linear correlation (r(2) 0.6628, p<0.0001). In cancer NAF samples (containing higher amounts of aluminium salts) we also found a significantly increased levels of pro-inflammatory cytokines (IL-1?, IL-6, IL-12 p70, and TNF-?) and chemoattractant CC and CXC chemokines (IL-8, MIP-1? and MCP-1). In 12 invasive cancer NAF samples we found a significant positive linear correlation among aluminium, carbonyls and pro-inflammatory IL-6 cytokine (Y=64.79x-39.63, r(2) 0.8192, p<0.0005), as well as pro-inflammatory monocyte chemoattractant MCP-1 cytokine (Y=2026x-866, r(2) 0.9495, p<0.0001). In addition to emerging evidence, our results support the possible involvement of aluminium ions in oxidative and inflammatory status perturbations of breast cancer microenvironment, suggesting aluminium accumulation in breast microenvironment as a possible risk factor for oxidative/inflammatory phenotype of breast cells. PMID:23916117

Mannello, F; Ligi, D; Canale, M

2013-07-12

83

A field aluminium speciation method to study the aluminium hazard in water  

Microsoft Academic Search

The toxicity of aluminium is governed by its bioavailability. Therefore, the speciation of aluminium in drinking water becomes\\u000a of prime importance to understand its fate and the population exposure, and to develop guidelines for the concentration levels.\\u000a At Health Canada, a field speciation method has been developed to perform on-site speciation followed by measurement of Al\\u000a in the laboratory. The

Denis Bérubé; Denis G. Brûlé

1999-01-01

84

Properties of aluminium oxide coating on aluminium alloy produced by micro-arc oxidation  

Microsoft Academic Search

Aluminium oxide coating was directly synthesized on aluminium alloy by micro-arc oxidation (MAO) in NaAlO2 solution. XRD results show that the coating consists of ?-Al2O3 and ?-Al2O3 in its whole thickness; the content of ?-Al2O3 in the coating is 64±4%. The coating consists of a relatively compact inner layer and a porous outer layer, and its porosity is 7–10%. The

Xin Shi-Gang; Song Li-Xin; Zhao Rong-Gen; Hu Xing-Fang

2005-01-01

85

Electrogeneration of aluminium to remove silica in water.  

PubMed

This paper presents the results of a study on electrogeneration of aluminium, as a coagulant to remove silica in make-up water for cooling towers. Three electrochemical systems were tested, two with aluminium electrodes (one with polarity change and another without it), and a third one with aluminium anodes and cathodes of stainless steel. From the obtained results it was concluded that under the studied conditions, the most advantageous system to produce aluminium and remove silica is the one with both electrodes of aluminium working with direct current. Due to chemical production of aluminium at the cathode, the concentration of aluminium in the water at the outlet of the electrochemical reactor is much higher than the one calculated according to Faraday's law. Under the tested conditions it was possible to remove up to 66% of silica from water containing around 50 mg L(-1). PMID:22258672

Gelover-Santiago, S L; Pérez-Castrejón, S; Martín-Domínguez, A; Villegas-Mendoza, I E

2012-01-01

86

Inductively coupled plasma nitriding of aluminium  

Microsoft Academic Search

Substrates of aluminium alloy 2011 were plasma nitrided using an inductively coupled plasma source. The plasma nitriding parameters of temperature, length of nitriding and negative dc bias of the substrates were varied in order to optimise the plasma nitriding process. Substrates were characterised by powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). All nitriding was

Sabina Gredelj; Andrea R. Gerson; Sunil Kumar; Giuseppe P. Cavallaro

2002-01-01

87

Aluminium potroom asthma: the Norwegian experience.  

PubMed

Work-related asthma in aluminium potroom workers, is reviewed and discussed, mainly on the basis of own investigations. The occurrence of work-related asthma has been shown to be associated with the duration of potroom employment, although the prevalence of asthmatic symptoms is not significantly different from that of the general population. Typical manifestations of occupational asthma are described in potroom workers, and a close relationship between the levels of fluoride exposure and work-related asthmatic symptoms has been observed. The existence of occupational asthma in aluminium potroom workers has been confirmed by characteristic patterns of repeated peak flow measurements, supported by changes in methacholine responsiveness in workers with suspected work-related asthma. However, no immunological test is available to establish the diagnosis. Methacholine challenge appears to be inappropriate for screening aluminium potroom workers in order to detect work-related asthma. Current smoking, but not self-reported allergy, is a risk factor for potroom asthma. A family history of asthma and previous occupational exposure may have some effect on the risk of developing symptoms. The prognosis of potroom asthma seems to depend on early replacement to unexposed work. The pathogenetic mechanisms are unknown, although some studies indirectly imply a hypersensitivity reaction. Future studies involving specific bronchial challenge appear to be necessary to find the causal agent(s) of aluminium potroom asthma. PMID:8143817

Kongerud, J; Boe, J; Søyseth, V; Naalsund, A; Magnus, P

1994-01-01

88

Thermopower of Molten Aluminium in Ultrasonic Field  

Microsoft Academic Search

Temperature dependence on the liquid aluminium thermopower is reported for the range 933--1043 K. In order to highlight the ultrasonic wave effect on the thermoelectric power, the experiments were carried out under similar conditions with and without sonication. The lower values of the thermopower in sonication conditions are explained by the decrease in the melt temperature gradient and due to

L. Moraru

2002-01-01

89

EIS testing of new aluminium sacrificial anodes  

Microsoft Academic Search

Aluminium alloys In\\/Hg free, suitable as sacrificial anodes for cathodic protection, have been developed. Short-term electrochemical tests were performed on these new alloys to obtain their electrochemical efficiency and to reveal any tendencies to passivation. Samples were galvanostatically held at different current densities, which changed every 24 h according to DNV RP 401. Electrochemical impedance spectroscopy (EIS), polarization curves and

M. A. Talavera; S. Valdez; J. A. Juarez-Islas; B. Mena; J. Genesca

2002-01-01

90

Two-photon excitation of aluminium phthalocyanines  

SciTech Connect

A demonstration is given of the feasibility of two-photon excitation of aluminium phthalocyanine and of the pharmaceutical preparation 'Fotosens', used in photodynamic therapy. The excitation source was an Nd:YAG laser emitting at the 1064 nm wavelength. The spectra of the two-photon-excited luminescence were obtained and the two-photon absorption cross sections were determined. (lasers in medicine)

Meshalkin, Yu P; Alfimov, E E; Makukha, V K [Novosibirsk State Technical University, Novosibirsk (Russian Federation); Vasil'ev, N E; Denisov, A N; Ogirenko, A P [Siberian Laser Medicine Centre, Novosibirsk (Russian Federation)

1999-12-31

91

Thermal Management of Aluminium Cell Bath Crust  

Microsoft Academic Search

When a consumed carbon anode in an aluminium electrolysis cell is replaced, the solid crust covering the anode and the bath is removed and transported in hopper cars to a cooling area where it remains for a period of one to four days, or more, to cool from a temperature of approximately 900°C to an acceptable temperature for autogenous milling,

J. Kirney; J. Thibault; B. Kruczek; A. Plumpton

2007-01-01

92

Aluminium alloy corrosion detection by magnetic measurements  

Microsoft Academic Search

During corrosion, currents passing from anodes to cathodes generate magnetic fields. Pitting corrosion of aluminium alloys in aggressive media was detected through magnetic field measurements, without electrical connection to the sample and without reference or auxillary electrodes in the corrosion cell. A sodium chloride solution containing hydrogen peroxide or a solution of potassium hydroxide 2 mol l-1 solution was used

C. Andrieu; F. Dalard; J. J. Rameau; F. Alcouffe; M. Reboul

1998-01-01

93

Electron Conditioning of Technical Aluminium Surfaces.  

National Technical Information Service (NTIS)

The effect of electron conditioning on commercially aluminium alloys 1100 and 6063 were investigated. Contrary to the assumption that electron conditioning, if performed long enough, can reduce and stabilize the SEY to low values (= 1.3, value of many pur...

F. L. Pimpec F. King R. E. Kirby

2004-01-01

94

Ultraprecision diamond turning of aluminium single crystals  

Microsoft Academic Search

Ultraprecision diamond turning is an important technology to generate a high surface finish in precision components and optics. In this paper, the diamond turning of aluminium single crystal rods with crystallographic axes normal to , and is analysed. The effect of the crystallographic anisotropy on the machining of these single crystals is investigated in the light of the mechanics of

S. To; W. B. Lee; C. Y. Chan

1997-01-01

95

Adhesive strength of powder coated aluminium substrates  

Microsoft Academic Search

Adhesive strengths of differently pretreated powder coated aluminium substrates were evaluated using the pull-off and the tape tests in the dry and wet conditions. Various accelerated test chambers were employed to evaluate the corrosion behaviour of the samples. Scanning electron microscopy (SEM), with energy dispersive X-ray analysis (EDX) were also employed to the better understanding of the nature and morphology

S. M. Mirabedini; J. D. Scantlebury; G. E. Thompson; S. Moradian

2005-01-01

96

Examination of the effect of Sc on 2000 and 7000 series aluminium alloy castings: for improvements in fusion welding  

Microsoft Academic Search

It has been reported that small additions of scandium (Sc) can improve the weldability and mechanical properties of some aluminium aerospace alloys that are normally considered to be ‘unweldable’. In order to determine the mechanisms by which these improvements occur, and more rapidly arrive at optimum Sc addition levels, small wedge-shaped castings have been used to simulate the cooling rates

A. F Norman; K Hyde; F Costello; S Thompson; S Birley; P. B Prangnell

2003-01-01

97

Nouveau procédé de synthèse du nitrure d'aluminium  

NASA Astrophysics Data System (ADS)

Thermodynamic considerations show that, even at room temperature, pure aluminium can react with nitrogen to form the aluminium nitride AlN. However, pure aluminium does not exist: it is always surrounded by an alumina shell that protects the metal from further reactions. Furthermore, in the hypothesis where one has been able to make aluminium react with nitrogen, an aluminium nitride shell will protect as well the metal core from further oxidation. Prompted by the Lanxide process allowing to form Al/Al2O3 composites, we have mixed aluminium powders with lithium salts, and easily synthesized pure aluminium nitride by heating the mixed powders in nitrogen at temperatures ranging from 800 to 1200 °C. Starting from aluminium powders with a specific area ranging from 0.3 to 4 m^2/g, we have been able to produce aluminium nitride with specific are ranging from 1 to 20 m^2/g. Mixed with Y203-CaO and sintered at 1720 °C in N2, we obtained AIN ceramics owning 92% density and 160 W/m.K thermal conductivity. Les calculs thermodynamiques montrent que, même à température ambiante, l'aluminium pur peut réagir avec l'azote pour former le nitrure d'aluminium AlN. Cependant, la poudre d'aluminium pur n'existe pas : ses grains sont toujours entourés d'une couche d'alumine protectrice. De plus, dans l'hypothèse où l'on pourrait faire réagir de la poudre d'aluminium avec de l'azote, il se formerait de même une couche protectrice de nitrure d'aluminium qui empêcherait le centre des grains de réagir. S'inspirant du “procédé Lanxide” permettant de réaliser des composites Al/Al2O3, nous avons mélangé de la poudre d'aluminium avec des sels de lithium, et synthétisé du nitrure d'aluminium pur en portant ce mélange dans l'azote à une température pouvant être comprise entre 800 et 1 200 °C. Utilisant des poudres d'aluminium possédant une surface spécifique comprise entre 0,3 et 4 m^2/g, nous avons obtenu une poudre de nitrure d'aluminium avec une surface spécifique comprise entre 1 et 20 m^2/g. Mélangeant classiquement cette poudre avec Y2O3-CaO, nous avons obtenu après frittage à 1 720 °C dans N2 des céramiques densifiées à 92 % et possédant une conductivité thermique de 160 W/m.K.

Haussonne, J. M.; Lostec, J.; Bertot, J. P.; Lostec, L.; Sadou, S.

1993-04-01

98

Content and bioaccessibility of aluminium in duplicate diets from southern Spain.  

PubMed

Aluminium is found naturally in foods and beverages, but levels increase notably during processing, packaging, storage, and cooking, as a consequence of its presence in food additives and the wide use of aluminium utensils and vessels. Dietary intake of Al was estimated in 2 population groups in southern Spain (families and university students) in a duplicate diet sampling study. Diets were sampled for 7 consecutive days, and Al was determined in acid-mineralized samples with electrothermal atomization-atomic absorption spectrometry (ETA-AAS). Mean values for Al intake were 2.93 and 1.01 mg/d in families and students, respectively, ranging from 0.12 to 10.00 mg/d. Assuming an average adult weight of 60 kg, the mean dietary exposures to aluminium were 0.34 and 0.12 mg/kg body weight/week in these groups, which amounted to 17% and 6% of the 2 mg/kg body weight estimated as the tolerable weekly intake by the Joint FAO/WHO Expert Committee on Food Additives. Bioaccessibility of dietary Al tested with in vitro studies ranged from 0.30 to 17.26% (absorbable fraction). The highest aluminium intakes were observed in subjects consuming diets with a low adherence to the Mediterranean diet, which were associated to high consumption of processed and canned food. On the contrary, subjects consuming diets with a high adherence to the Mediterranean diet patterns showed the lowest Al intakes. The present findings are useful for giving both a reliable estimate of total aluminium dietary intake and tolerable intake levels according to usual dietary habits. PMID:23957422

Cabrera-Vique, Carmen; Mesías, Marta

2013-08-01

99

Crucial role for the Nalp3 inflammasome in the immunostimulatory properties of aluminium adjuvants.  

PubMed

Aluminium adjuvants, typically referred to as 'alum', are the most commonly used adjuvants in human and animal vaccines worldwide, yet the mechanism underlying the stimulation of the immune system by alum remains unknown. Toll-like receptors are critical in sensing infections and are therefore common targets of various adjuvants used in immunological studies. Although alum is known to induce the production of proinflammatory cytokines in vitro, it has been repeatedly demonstrated that alum does not require intact Toll-like receptor signalling to activate the immune system. Here we show that aluminium adjuvants activate an intracellular innate immune response system called the Nalp3 (also known as cryopyrin, CIAS1 or NLRP3) inflammasome. Production of the pro-inflammatory cytokines interleukin-1beta and interleukin-18 by macrophages in response to alum in vitro required intact inflammasome signalling. Furthermore, in vivo, mice deficient in Nalp3, ASC (apoptosis-associated speck-like protein containing a caspase recruitment domain) or caspase-1 failed to mount a significant antibody response to an antigen administered with aluminium adjuvants, whereas the response to complete Freund's adjuvant remained intact. We identify the Nalp3 inflammasome as a crucial element in the adjuvant effect of aluminium adjuvants; in addition, we show that the innate inflammasome pathway can direct a humoral adaptive immune response. This is likely to affect how we design effective, but safe, adjuvants in the future. PMID:18496530

Eisenbarth, Stephanie C; Colegio, Oscar R; O'Connor, William; Sutterwala, Fayyaz S; Flavell, Richard A

2008-05-21

100

Addition Facts  

NSDL National Science Digital Library

Play these addition games to review your addition facts. 1. First, to review of your addition facts you will practice them by using these flashcards. Flashcards After you review your addition facts by using the flashcards, you get to play some addition games! Try your hardest and have fun! 2. Play this addition fishing game Addition Fishing Game 3. Next you get to practice your ...

Felsted, Ms.

2010-04-12

101

Modelling of Laser Spall Experiments on Aluminium  

NASA Astrophysics Data System (ADS)

Recently a series of shots have been fired on the AWE HELEN 2TW high power laser in order to study the spall of aluminium at high strain rates (1). In the first shot a radiograph was taken which showed a spall layer had formed. Further shots were fired and the free surface velocity of the aluminium was obtained using interferometry. Several of these shots showed that spall had occurred. This paper attempts to model these shots using the extended Johnson spall model (2,3). Previously determined spall parameters (3), which model low strain rate plate impact experiments, are found not to model the spall well, so new spall parameters are determined that match the laser results.

Robinson, C. M.

2002-07-01

102

Fluidity of mica particle dispersed aluminium alloy  

Microsoft Academic Search

Cast aluminium alloy-mica particle composites were made by dispersing mica particles in a vortex produced by stirring the liquid Al-4 wt% Cu-1.5 wt% Mg alloy and then casting the melt containing the suspended particles into permanent moulds. Spiral fluidity and casting fluidity of the alloy containing mica particles in suspension were determined. Both the spiral fluidity and the casting fluidity

Deonath; P. K. Rohatgi

1980-01-01

103

Oxidation behavior of titanium-aluminium nitrides  

Microsoft Academic Search

Oxidation behavior of titanium-aluminium nitrides of various compositions has been explored to understand the oxidation protection mechanisms and the role of structure and composition in the oxidation behavior. Thin films of (Ti1-x,Alx)N have been sputter deposited on silicon substrates and the nature of oxides resulting from air oxidation at various temperatures has been evaluated using Auger electron spectroscopy. In most

A. Joshi; H. S. Hu

1995-01-01

104

Sustainability of the European Aluminium Industry 2010  

NSDL National Science Digital Library

This report by the European Aluminium Association (EAA) was created to analyze and document the efforts of Europeâs aluminum industry to remain competitive, grow, and become more environmentally friendly. Recommendations and reviews are formed based on 34 âSustainable Development Indicators.â New in the 2010 report is the use sustainability indicators to address the use of aluminum in key applications. Highlighted improvements for 2010 are emissions, natural resource use, worker safety, training, and recycling.

Association, European A.

105

Aluminium phosphide poisoning: a case report.  

PubMed

This paper reports the case of a family in which three children were presented at Emergency Room (ER) with poisoning after the use of a pesticide at home. Initially, the cases were managed as routine cases of organophosphorus poisoning; however, the death of two children made the health team members realise that the poison's effects were delayed and devastating. Later, the compound was identified as Aluminium Phosphide (ALP), and the life of the last surviving child in the family was saved. PMID:22455303

Hirani, Shela Akbar Ali; Rahman, Arshalooz

106

Plastic anisotropy in aluminium drawn tubes  

Microsoft Academic Search

Developments of plastic anisotropy in aluminium tubes are investigated experimentally and theoretically. Asreceived drawn\\u000a tubes are tensioned or twisted to get speciments having different anisotropies. The tubes are cut and extended into flat sheets.\\u000a The surfaces are removed mechanically and electorochemically into half thickness. The anisotropy is evaluated by flow stress\\u000a and r-value of tensile tests in various directions in

Hiroshi Takahashi; Junji Moro; Shin Tsuchida

1998-01-01

107

MetalCeramic Interfaces in Laser Coated Aluminium Alloys  

Microsoft Academic Search

Abstraet--A novel process was developed to firmly coat an aluminium alloy, A16061, with ~t-Al203 by means of laser processing. In this approach a mixture of SiO2 and A1 powder was used to inject in the laser melted surface of aluminium. A reaction product ~t-Al203 layer of a thickness of 100\\/~ m was created which was well bonded to the aluminium

X. B. Zhou; J. Th. M. De Hosson

1994-01-01

108

Processes of combustion of aluminium particles in gas discharge  

NASA Astrophysics Data System (ADS)

The regime of combustion of aluminium microparticles involving oxidant molecules is analyzed if heating of these particles leads to evaporation of aluminium atoms from the particle surface which form aluminium nanoclusters and they, in turn, partake in chemical reactions. It is shown that the chemical process cannot provide the particle heating for this regime, and it results from particle heating by an external field of gas discharge.

Kashtanov, P. V.; Smirnov, B. M.; Bityurin, V. A.; Klimov, A. I.

2011-11-01

109

Renal aluminium handling in the rat: a micropuncture assessment.  

PubMed

Uncertainties exist over the glomerular filtration of aluminium and virtually nothing is known about its segmental handling along the nephron. The present study has used micropuncture, combined with electrothermal atomic absorption spectroscopy, to determine directly the aluminium content of glomerular filtrate and of late PCTs (proximal convoluted tubules) and early distal tubules in anaesthetized Munich-Wistar rats infused with three different doses of aluminium citrate (plasma aluminium concentrations, 2.9+/-0.1, 5.2+/-0.4 and 10.0+/-0.9 microg.ml(-1) respectively). Aluminium filtration into Bowman's space was found to be considerably greater than that predicted by an in vitro filtration system: in all three groups it was essentially filtered freely. No significant aluminium reabsorption took place along the PCT, but with every dose the FD(Al) (fractional delivery of aluminium; tubular fluid:plasma aluminium/inulin concentration ratio) was lower at the early distal site than at the late PCT (P<0.001 in each case), indicating net aluminium reabsorption in the loop of Henle. This reabsorption amounted to 19-26% of the filtered aluminium load. In the low- and medium-dose groups, there was no significant difference between FD(Al) at the early distal site and that in the final urine; however, in the high-dose group, FD(Al) in the urine (1.02+/-0.06) exceeded that at the early distal tubule (0.75+/-0.04; P<0.001), suggesting aluminium secretion in the distal nephron. The results indicate that aluminium loads, when complexed with citrate, are excreted efficiently owing to a combination of glomerular filtration and minimal reabsorption. PMID:15053741

Shirley, David G; Walter, Mary F; Walter, Stephen J; Thewles, Andrew; Lote, Christopher J

2004-08-01

110

Citric acid as corrosion inhibitor for aluminium pigment  

Microsoft Academic Search

Aluminium pigments corrode in aqueous alkaline media (e.g., water-borne paints) with the evolution of hydrogen.The hydrogen corrosion of aluminium pigment can be inhibited by the chelating agent citric acid, which is a renewable raw material and absolutely non-toxic. At pH 8 more hydrogen is evolved as at pH 10 which can be explained with the isoelectric point of aluminium oxide

B. Müller

2004-01-01

111

Deep drawing of aluminium–steel tailor-welded blanks  

Microsoft Academic Search

Aluminium and steel blank sheets can be welded together to produce tailor-welded blanks with strength mismatch. These tailor-welded blanks are applied in aerospace and automotive industries. In this investigation, finite element simulations were carried out using home code DD3IMP to determine the formability characteristics of aluminium–steel tailor-welded blanks. Aluminium (AA6016-T4) blank sheet was combined with a range of steel blank

R. Padmanabhan; M. C. Oliveira; L. F. Menezes

2008-01-01

112

Aluminium production as a source of atmospheric carbonyl sulfide (COS)  

Microsoft Academic Search

Carbonyl sulfide is found as a major sulfur compound in anodic gases of commercial aluminium electrolysis. Recent spectroscopic\\u000a measurements on industrial aluminium smelters found typical CO\\/COS ratios between 80 and 200. This results in specific COS\\u000a emissions of between 1 and 7 kg\\/t(Al) if all COS is released into the atmosphere. In 1993 aluminium production would have\\u000a been responsible for

Jochen Harnisch; Reinhard Borchers; Peter Fabian; Kostas Kourtidis

1995-01-01

113

Crediting aluminium recycling in LCA by demand or by disposal  

Microsoft Academic Search

Background, Aim and Scope  By using recycled aluminium or by disposing used aluminium products for recycling, it is normal LCA practice to give a credit\\u000a for the avoided production of primary or recycled aluminium. Lately, consequential approaches have been suggested to qualify\\u000a and quantify this credit in terms of market mechanisms. Depending on supply, demand and price elasticity of primary products

Niels Frees

2008-01-01

114

Experiences with the critical review process of aluminium LCI data  

Microsoft Academic Search

Background, aim, and scope  This paper summarises the critical review process according to ISO 14040\\/44 performed for the European Aluminium Association\\u000a (EAA), Brussels. Scope of the review was a life cycle inventory (LCI) project, aiming at providing the life cycle assessment\\u000a (LCA) community with reliable generic data relevant for the European aluminium market, including the production of aluminium\\u000a ingot either from

Walter Klöpffer

2009-01-01

115

Improving the Crashworthiness of Aluminium Rail Vehicles  

NASA Astrophysics Data System (ADS)

An experimental and modelling programme of work have been undertaken to predict the performance of aluminium welds in rail vehicles under highly dynamic loading conditions and provide design guidelines to reduce the likelihood of the occurrence of weld unzipping. Modelling of weld unzipping in large rail structures is a challenging task since it requires to deal with material instability, to take into account the uncertainties in material parameters and to address the problem of mesh resolution which together pose severe challenges to computability. The proposed methodology to the prediction of weld failure is based on the validation of the numerical models through correlation with laboratory scale tearing tests. The tearing tests were conducted on samples taken from real rail extrusions with the purpose of obtaining the failure parameters under dynamic loading and understanding the effect of weld material composition on joint behaviour. The validated material models were used to construct a FEA simulation of the collision of an aluminium rail car and investigate the effect of both joint geometry and welding techniques on the failure mechanism. Comparisons of the model with the failures observed in an aluminium rail vehicle that was involved in a high speed collision, have shown that it is possible to model the phenomenon of weld unzipping with good accuracy. The numerical models have also been used as a tool for the optimisation of joint design to improve crashworthiness.

Zangani, Donato; Robinson, Mark; Kotsikos, George

116

Mechanical Properties of Particulate Reinforced Aluminium Alloy Matrix Composite  

NASA Astrophysics Data System (ADS)

This paper discusses the mechanical properties of Titanium Carbide (TiC) particulate reinforced aluminium-silicon alloy matrix composite. TiC particulate reinforced LM6 alloy matrix composites were fabricated by carbon dioxide sand molding process with different particulate weight fraction. Tensile strength, hardness and microstructure studies were conducted to determine the maximum load, tensile strength, modulus of elasticity and fracture surface analysis have been performed to characterize the morphological aspects of the test samples after tensile testing. Hardness values are measured for the TiC reinforced LM6 alloy composites and it has been found that it gradually increases with increased addition of the reinforcement phase. The tensile strength of the composites increased with the increase percentage of TiC particulate.

Sayuti, M.; Sulaiman, S.; Baharudin, B. T. H. T.; Arifin, M. K. A.; Suraya, S.; Vijayaram, T. R.

2011-01-01

117

Effects of additives on zinc electrowinning from industrial waste products  

Microsoft Academic Search

An investigation of the effects of some additives on zinc electrowinning from a weak acidic sulphate electrolyte prepared from an industrial waste product has been carried out. Experiments were done in the presence of additives such as aluminium sulphate, animal glue and an extract of horse-chestnut nuts (HCE), used alone or in different mixtures.Using a rotating disc electrode (RDE) and

Liana Mure?an; G. Maurin; L. Oniciu; Silvia Avram

1996-01-01

118

Numerical simulation of early stages of oxide formation in molten aluminium–magnesium alloys in a reverberatory furnace  

Microsoft Academic Search

A significant amount of aluminium is processed by melting aluminium scrap that contains small amounts of magnesium. A major drawback of aluminium production in secondary melt furnaces is the formation of dross or aluminium oxide by the oxidation of the molten metal. Since aluminium scrap forms a major source of the metal in secondary aluminium processing, the presence of alloying

Anindya Kanti De; Achintya Mukhopadhyay; Swarnendu Sen; Ishwar K Puri

2004-01-01

119

A Trace Element Effect in Alloys based on the Aluminium-Zinc-Magnesium System  

Microsoft Academic Search

THE remarkable changes in properties which may be achieved by the addition of small quantities, or traces, of certain elements to age-hardening alloy systems has aroused much interest recently. A notable example is the pronounced effect of traces of cadmium, indium, or tin on the elevated temperature ageing characteristics of aluminium-copper alloys1. Similar observations have been made in a number

I. J. Polmear

1960-01-01

120

The study of aluminium anodes for high power density Al\\/air batteries with brine electrolytes  

Microsoft Academic Search

Aluminium alloys containing small additions of both tin (?0.1wt%) and gallium (?0.05wt%) are shown to dissolve anodically at high rates in sodium chloride media at room temperatures; current densities >0.2Acm?2 can be obtained at potentials close to the open circuit potential, ??1500mV versus SCE. The tin exists in the alloys as a second phase, typically as ?1?m inclusions (precipitates) distributed

Maria Nestoridi; Derek Pletcher; Robert J. K. Wood; Shuncai Wang; Richard L. Jones; Keith R. Stokes; Ian Wilcock

2008-01-01

121

Risk of acute toxicity for fish during aluminium application to hardwater lakes  

Microsoft Academic Search

To assess the risk of aluminium (Al) toxicity during the restoration of the eutrophic lake Tiefwarensee by hypolimnetic addition of NaAl(OH)4-solution (aluminate) the generally limnological monitoring was accompanied by fractionation of Al in water and using Al accumulation on fish gills as bioindicator. The concentration of reactive Al species in the alkaline water (pH 8) peaked at 2mgL?1 in parts

Gerlinde Wauer; Hans-Christian Teien

2010-01-01

122

Preparation of orientated aluminium nitride films by radio-frequency reactive sputtering  

Microsoft Academic Search

Aluminium nitride (A1N) is a very attractive material because of its refractory insulating properties. This is promising for use in the passivation of semiconductor surfaces and insulators for high temperature [1-3]. Since it also has the high thermal conductivity, it is a candidate for the substrate in thin film devices [4, 5]. In addition, A1N has a wide band gap

K. Sugiyama; K. Taniguchi; K. Kuwabara

1990-01-01

123

The long-term behaviour of an aluminium-reinforced polyethylene pressure pipe  

Microsoft Academic Search

The long-term behaviour of an aluminium-reinforced polyethylene pressure pipe has been explored by undertaking stress rupture tests at 60 and 80 °C. The results of the tests showed these macrocomposite pipes have a time-dependent strength, such that with an increasing time under load the strength declined. In addition the pipes were weaker at 80 °C when compared to the 60

J. Bowman

1993-01-01

124

Prevalence of beryllium sensitization among aluminium smelter workers  

PubMed Central

Background Beryllium exposure occurs in aluminium smelters from natural contamination of bauxite, the principal source of aluminium. Aims To characterize beryllium exposure in aluminium smelters and determine the prevalence rate of beryllium sensitization (BeS) among aluminium smelter workers. Methods A population of 3185 workers from nine aluminium smelters owned by four different aluminium-producing companies were determined to have significant beryllium exposure. Of these, 1932 workers participated in medical surveillance programmes that included the serum beryllium lymphocyte proliferation test (BeLPT), confirmation of sensitization by at least two abnormal BeLPT test results and further evaluation for chronic beryllium disease in workers with BeS. Results Personal beryllium samples obtained from the nine aluminium smelters showed a range of <0.01–13.00 ?g/m3 time-weighted average with an arithmetic mean of 0.25 ?g/m3 and geometric mean of 0.06 ?g/m3. Nine workers were diagnosed with BeS (prevalence rate of 0.47%, 95% confidence interval = 0.21–0.88%). Conclusions BeS can occur in aluminium smelter workers through natural beryllium contamination of the bauxite and further concentration during the refining and smelting processes. Exposure levels to beryllium observed in aluminium smelters are similar to those seen in other industries that utilize beryllium. However, compared with beryllium-exposed workers in other industries, the rate of BeS among aluminium smelter workers appears lower. This lower observed rate may be related to a more soluble form of beryllium found in the aluminium smelting work environment as well as the consistent use of respiratory protection.

Slade, M. D.; Cantley, L. F.; Kirsche, S. R.; Wesdock, J. C.; Cullen, M. R.

2010-01-01

125

Food additives  

Microsoft Academic Search

Food additives are discussed from the food technology point of view. The reasons for their use are summarized:(1) to protect food from chemical and microbiological attack;(2) to even out seasonal supplies;(3) to improve their eating quality;(4) to improve their nutritional value.The various types of food additives are considered, e.g. colours, flavours, emulsifiers, bread and flour additives, preservatives, and nutritional additives.

Michael Spencer

1974-01-01

126

Recovering obliterated engraved marks on aluminium surfaces by etching technique  

Microsoft Academic Search

A study has been made of the characteristics of restoration of obliterated engraved marks on aluminium surfaces by etching technique. By etching different reagents on 0.61mm thick sheets of aluminium (99wt%) on which some engraved marks had been erased to different depths it was found that the reagent 60% hydrochloric acid and 40% sodium hydroxide on alternate swabbing on the

Mohd. Izhar Mohd. Baharum; R. Kuppuswamy; Azari Abd. Rahman

2008-01-01

127

Electron microscopy and diffraction of aluminium oxide whiskers  

Microsoft Academic Search

Whiskers of ?-Al2O3 have been grown by the condensation and oxidation of aluminium on an alumina substrate, and examined by transmission electron microscopy and diffraction. Unbroken whiskers invariably terminate in a small globule of aluminium and have a ‘drumstick’ form. The most perfect whiskers are ribbons with their principal surfaces parallel to the (0001) planes; the majority of these have

D. J. Barber

1964-01-01

128

Investigation into the properties of friction-welded aluminium bars  

Microsoft Academic Search

The replacement of copper by aliminium is inevitable for certain application in the electrical industry due to economic reasons. Whilst in the majority of cases, aluminium can be joined only by adhesive bonding, mechanical fastening and solid-phase welding techniques. Friction welding offers an alternative welding process for the joining the aluminium bars. Frinction welding is well known for its ability

Bekir S. Yilbas; Ahmet Z. Sahin; Ali Coban; B. J. Abdul Aleem

1995-01-01

129

Subendocardial infarction in a young survivor of aluminium phosphide poisoning  

Microsoft Academic Search

Aluminium phosphide is a solid fumigant pesticide and has systemic toxicity due to liberation of phosphine gas. We report a case of aluminium phosphide poisoning with systemic toxicity in a 16-year-old patient who developed previously undocumented complication of subendocardial infarction, with characteristic electrocardiographic changes reverting back to normal after a period of 10 weeks, even though the patient had clinical

Rajeev M Kaushik; Reshma Kaushik; Sukhdev K Mahajan

2007-01-01

130

Obtaining weld pool vision information during aluminium alloy TIG welding  

Microsoft Academic Search

An image sensing system for the TIG (tungsten inert-gas arc) welding process of aluminium alloy was established. The relationships between the image sensing system and the characteristic of welding current were discussed in detail. Front and back images of the weld pool were obtained with different welding parameters. In order to process the image, the characteristics of an aluminium alloy

J. J. Wang; T. Lin; S. B. Chen

2005-01-01

131

Effect of aluminium speciation on fish in dilute acidified waters  

NASA Astrophysics Data System (ADS)

Acidification of lakes and streams is a serious water quality problem in high elevation granitic ecosystems in the northeastern US1-3. An important consequence of acidification is the mobilisation of aluminium from the edaphic to the aquatic environment3-5. Elevated levels of aluminium may have serious ramifications for biological communities, particularly fish, inhabiting acidified aquatic systems5,6. In this study, water quality data were collected from several acidified lakes and streams in the Adirondack region of New York state. The purpose of this investigation was to characterise aluminium chemistry in these acidified waters and to assess the relative toxicity of soluble aluminium species to fish. Aqueous aluminium speciation was found to be highly variable in Adirondack waters, and its effect on fish was also variable.

Driscoll, Charles T.; Baker, Joan P.; Bisogni, James J.; Schofield, Carl L.

1980-03-01

132

Multilayer roll bonded aluminium foil: processing, microstructure and flow stress  

SciTech Connect

Bulk aluminium has been produced by warm-rolling followed by cold-rolling of commercial purity (99% purity) aluminium foil. The bonding appeared perfect from observation with the naked eye, light and transmission electron microscopy. By comparison with bulk aluminium of similar purity (AA1200) rolled to a similar strain (90%RA), the roll-bonded metal showed a much higher density of high-angle grain boundaries, similar strength and improved thermal stability. This study has implications for a number of applications in relation to the processing of aluminium. Roll bonding is of interest as a method for grain size refinement; oxide-containing materials have increased strength, enhanced work-hardening behaviour, and exhibit alterations in recrystallisation behaviour. The behaviour of the hard oxide film is of interest in aluminium processing, and has been investigated by characterising the size and distribution of oxide particles in the roll-bonded samples.

Barlow, C.Y.; Nielsen, P.; Hansen, N

2004-08-02

133

Dissolved aluminium in the Southern Ocean  

NASA Astrophysics Data System (ADS)

Dissolved aluminium (Al) occurs in a wide range of concentrations in the world oceans. The concentrations of Al in the Southern Ocean are among the lowest ever observed. An all-titanium CTD sampling system makes it possible to study complete deep ocean sections of Al and other trace elements with the same high vertical resolution of 24 depths as normal for traditional CTD/Rosette sampling. Overall, 470 new data points of Al are reported for 22 full depth stations and 24 surface sampling positions along one transect. This transect consisted of 18 stations on the zero meridian proper from 51°57' S until 69°24'S, and 4 stations somewhat to the northeast towards Cape Town from 42°20'S, 09°E to 50°17'S, 01°27'E. The actual concentrations of Al in the Southern Ocean were lower than previously reported. The concentration of Al in the upper 25 m was relatively elevated with an average concentration of 0.71 nM ( n=22; S.D.=0.43 nM), most likely due to atmospheric input by a suggested combination of direct atmospheric (wet and dry) input and indirect atmospheric input via melting sea ice. Below the surface waters there was a distinct Al minimum with an average concentration of 0.33 nM ( n=22; S.D.=0.13 nM) at an average depth of 120 m. In the deep southernmost Weddell Basin the concentration of Al increased with depth to ˜0.8 nM at 4000 m, and a higher concentration of ˜1.5 nM in the ˜4500-5200 m deep Weddell Sea Bottom Water. Over the Bouvet triple junction region, where three deep ocean ridges meet, the concentration of Al increased to ˜1.4 nM at about 2000 m depth over the ridge crest. In the deep basin north of the Bouvet region the concentration of Al increased to higher deep values of 4-6 nM due to influence of North Atlantic Deep Water. In general the intermediate and deep distribution of Al results from the mixing of water masses with different origins, the formation of deep water and additional input from sedimentary sources at sea floor elevations. No significant correlation between Al and silicate (Si) was observed. This is in contrast to some other ocean regions. In the Southern Ocean the supply of Al is extremely low and any signal from Al uptake and dissolution with biogenic silica is undetectable against the high dissolved Si and low dissolved Al concentrations. Here the Al-Si relation in the deep ocean is uncoupled. This is due to the scavenging and subsequent loss of the water column of Al, whereas the concentration of Si increases in the deep ocean due to its input from deep dissolution of biogenic diatom frustules settling from the surface layer.

Middag, R.; van Slooten, C.; de Baar, H. J. W.; Laan, P.

2011-12-01

134

The effective thermal conductivity of insulation materials reinforced with aluminium foil at low temperatures  

NASA Astrophysics Data System (ADS)

The effective thermal conductivity (ETC) of multilayer thermal insulation materials was experimentally investigated as a function of temperature (0-25 °C). The materials consisted of binary/ternary glass wools or ternary expanded polystyrene foams reinforced with aluminium foil. The experimental measurements were performed using a guarded hot plate with temperature differences of 5, 10 and 15 °C. The results indicated that significant correlations exist between ETC and the characteristics of the materials with decreasing temperature. The ETC decreases with reinforcement with aluminium foil at the same temperature or with temperature differences of 5 and 15 °C. In addition, it was clearly observed that the ETC decreases sharply with decreased temperature. Consequently, reflective materials may reduce the ETC at low temperatures.

Yüksel, N.; Avc?, A.; K?l?ç, M.

2012-09-01

135

Reconstruction of 2D Al3Ti on TiB2 in an aluminium melt  

NASA Astrophysics Data System (ADS)

It has been widely considered that Al3Ti is involved in the aluminium nucleation on TiB2, although the mechanism has not been fully understood. In this paper molecular dynamics has been conducted to investigate this phenomenon at an atomistic scale. It was found that a two-dimensional Al3Ti layer may remain on TiB2 above the aluminium liquidus. In addition, the results showed that this 2D Al3Ti undergoes interface reconstruction by forming a triangular pattern. This triangular pattern consists of different alternative stacking sequences. The transition region between the triangles forms an area of strain concentration. By means of this mechanism, this interfacial Al3Ti layer stabilizes itself by localizing the large misfit strain between TiB2 and Al3Ti This reconstruction is similar to the hdp-fcc interface reconstruction in other systems which has been observed experimentally [1].

Qin, T.; Fan, Z.

2012-01-01

136

Evaluation of the mechanical properties of microarc oxidation coatings and 2024 aluminium alloy substrate  

NASA Astrophysics Data System (ADS)

A determination of the phase constituents of ceramic coatings produced on Al-Cu-Mg alloy by microarc discharge in alkaline solution was performed using x-ray diffraction. The profiles of the hardness, H, and elastic modulus, E, across the ceramic coating were determined by means of nanoindentation. In addition, a study of the influence of microarc oxidation coatings on the tensile properties of the aluminium alloy was also carried out. The results show that the H-and E-profiles are similar, and both of them exhibit a maximum value at the same depth of coating. The distribution of the ?-Al2O3 phase content determines the H- and E-profiles of the coatings. The tensile properties of 2024 aluminium alloy show less change after the alloy has undergone microarc discharge surface treatment.

Xue, Wenbin; Wang, Chao; Deng, Zhiwei; Chen, Ruyi; Li, Yongliang; Zhang, Tonghe

2002-11-01

137

EFFECT OF SHOT PEENING ON FATIGUE PERFORMANCE OF ADVANCED ALUMINIUM ALLOYS AND ALUMINIUM BASED METAL MATRIX COMPOSITES  

Microsoft Academic Search

Future airframe designs may incorporate the lightweight lithium-containing aluminium alloys and silicon carbide reinforced aluminium alloys which offer enhanced specific stiffness and strength. The present research set out to investigate the influence of shot peening on the fatigue performance of the monolithic and composite materials under rotating bend loading conditions with a stress ratio R = -1. The metal matrix

138

Naturally occurring radioactive material from the aluminium industry—a case study: the Egyptian Aluminium Company, Nag Hammady, Egypt  

Microsoft Academic Search

The activity concentrations and the gamma-absorbed dose rates of the terrestrial naturally occurring radionuclides 226Ra and 232Th were determined in samples of bauxite, alumina and aluminium dross tailings industrial waste (used to produce two types of alums) using high purity germanium (HPGe) gamma ray spectrometry. The bauxite and alumina are imported by Egyptalum (The Egyptian Aluminium Company, Nag Hammady, Egypt)

Adel G E Abbady; A M El-Arabi

2006-01-01

139

Naturally occurring radioactive material from the aluminium industry---a case study: the Egyptian Aluminium Company, Nag Hammady, Egypt  

Microsoft Academic Search

The activity concentrations and the gamma-absorbed dose rates of the terrestrial naturally occurring radionuclides 226Ra and 232Th were determined in samples of bauxite, alumina and aluminium dross tailings industrial waste (used to produce two types of alums) using high purity germanium (HPGe) gamma ray spectrometry. The bauxite and alumina are imported by Egyptalum (The Egyptian Aluminium Company, Nag Hammady, Egypt)

Adel G. E. Abbady; A. M. El-Arabi

2006-01-01

140

Measurement of surface resistivity/conductivity of anodized aluminium alloy by optical interferometry techniques  

NASA Astrophysics Data System (ADS)

Optical interferometry techniques was used for the first time to measure the surface resistivity/conductivity of anodized aluminium samples in aqueous solution without any physical contact. The anodization process (oxidation) of the aluminium samples was carried out in different sulphuric acid solutions (1.0-2.5 % H2SO4), by the technique of electrochemical impedance spectroscopy (EIS), at room temperature. In the mean time, the real-time holographic interferometric was carried out to measure the thickness of anodized (oxide) film of the aluminium samples during the anodization processes. Then, the alternating current (AC) impedance (resistance) of the anodized aluminium samples was determined by the technique of electrochemical impedance spectroscopy (EIS) in different sulphuric acid solutions (1.0-2.5 % H2SO4) at room temperature. In addition, a mathematical model was derived in order to correlate between the AC impedance (resistance) and to the surface (orthogonal) displacement of the samples in solutions. In other words, a proportionality constant (surface resistivity or conductivity=1/ surface resistivity) between the determined AC impedance (by EIS technique) and the orthogonal displacement (by the optical interferometry techniques) was obtained. Consequently the surface resistivity (?) and conductivity (?) of the aluminum samples in solutions were obtained. Also, electrical resistivity values (?) from other source were used for comparison sake with the calculated values of this investigation. This study revealed that the measured value of the resistivity for the anodized aluminium samples were 2.8×109, 7×1012, 2.5×1013, and 1.4 ×1012 Ohms-cm in 1.0%,1.5%, 2.0%, and 2.5 % H2SO4 solutions, respectively. In fact, the determined value range of the resistivity is in a good agreement with the one found in literature for the aluminium oxide ,85% Al2O3 (5×1010 Ohms-cm in air at temperature 30C°), 96% Al2O3 (1×1014 Ohms-cm in air at temperature 30C°), and 99.7% Al2O3 (>1×1014 Ohmscm in air at temperature 30C°).

Habib, K.

2010-03-01

141

Study on aluminium-based single films.  

PubMed

In the present paper the authors studied isolated metallic films made from the same material used for making metallic foams, and then characterised their properties. Metal films were made from a liquid aluminium alloy reinforced with ceramic particles of known concentration. Melts without such particles were also investigated. It is shown that stable films could not be made from Al-Si alloy having no particles, and just extremely thin and fragile films could be made from commercially-pure Al. In contrast, aluminium alloys containing particles such as SiC and TiB(2) allowed pulling thin, stable films, which did not rupture. Significant thinning of films was observed when the particle concentration in the melt decreased. By in situ X-ray monitoring of liquid films during pulling, film thickness and drainage effects within the liquid film could be studied. The morphology and microstructure of films was characterised after solidification. Our work shows that the question of how foams are stabilised can be studied using a simplified system such as a film, instead of having to deal with the multitude of different structural elements present in a foam. PMID:18060172

Vinod Kumar, G S; García-Moreno, F; Babcsán, N; Brothers, A H; Murty, B S; Banhart, J

2007-10-10

142

Cholinergic System Under Aluminium Toxicity in Rat Brain  

PubMed Central

The present investigation envisages the toxic effects of aluminium on the cholinergic system of male albino rat brain. Aluminium toxicity (LD50/24 h) evaluated as per Probit method was found to be 700 mg/kg body weight. One-fifth of lethal dose was taken as the sublethal dose. For acute dose studies, rats were given a single lethal dose of aluminium acetate orally for one day only and for chronic dose studies, the rats were administered with sublethal dose of aluminium acetate once in a day for 25 days continuously. The two constituents of the cholinergic system viz. acetylcholine and acetylcholinesterase were determined in selected regions of rat brain such as cerebral cortex, hippocampus, hypothalamus, cerebellum, and pons-medulla at selected time intervals/days under acute and chronic treatment with aluminium. The results revealed that while acetylcholinesterase activity was inhibited, acetylcholine level was elevated differentially in all the above mentioned areas of brain under aluminium toxicity, exhibiting area-specific response. All these changes in the cholinergic system were subsequently manifested in the behavior of rat exhibiting the symptoms such as adipsia, aphagia, hypokinesia, fatigue, seizures, etc. Restoration of the cholinergic system and overt behavior of rat to the near normal levels under chronic treatment indicated the onset of either detoxification mechanisms or development of tolerance to aluminium toxicity in the animal which was not probably so efficient under acute treatment.

Yellamma, K.; Saraswathamma, S.; Kumari, B. Nirmala

2010-01-01

143

Food additives  

MedlinePLUS

... food additives have to do with man-made ingredients that are added to foods, including: Antibiotics given to food producing animals Antioxidants in oily or fatty foods Artificial sweeteners, such as aspartame, saccharine, and sodium cyclamate ...

144

Preparation and characterization of nanodispersions of yttria, yttrium aluminium garnet and lutetium aluminium garnet.  

PubMed

Refractory and chemically inert nanoparticulate solids like yttria, yttrium aluminium garnet or lutetium aluminium garnet are notoriously difficult to disperse in aqueous solution, although such dispersions might prove useful for 2D- and 3D-printing, deposition of films or other shaping procedures for ceramic green bodies. This work reports on experiments to prepare such dispersions from nanopowders, using a range of selected carboxylic acids as ligands for electrostatic charging and stabilization of the various nanomaterials. The assessment of the system properties achieved combines ?-potential and viscosity (flow curve) measurements in the resulting colloidal systems. Calculations of the molecular electrostatic potential of the ligands were used to correlate the molecular structure of the ligands and their capability to dock to the surface of the solid particles. The colloid chemical data received have then been interpreted on this background; citric acid and polyacrylic acid have been identified as the most attractive dispersants. PMID:23643249

Bredol, Michael; Micior, Joanna

2013-04-12

145

Aluminium and iron air pollution near an iron casting and aluminium foundry in Turin district (Italy).  

PubMed

This work reports the results of an environmental survey carried out in an industrial area in the Province of Turin: its main aim is to assess the levels of iron and aluminium in the outside air during the period from July to September to assess the influence of industrial activity (a cast-iron and aluminium foundry) which is interrupted during the month of August, on the level of metals present in the air. Conducting the analysis during this period of time made it possible to avoid the confounding effect of pollution due to domestic central heating. The measurements were taken from nine areas at different distances from the foundry in the area and according to the direction of the prevailing winds, as deduced from the historical data. The results of this survey show a statistically significant difference in iron and aluminium levels in the outside air in the geographic areas between the two main periods examined: during August (no foundry activity) v/s July-September (foundry activity). The values recorded are: Aluminium 0.4+/-0.45 microg/m(3) v/s 1.12+/-1.29 microg/m(3) (p<0.0001); Iron 0.95+/-0.56 microg/m(3) v/s 1.6+/-1.0 microg/m(3) (p<0.0001). There were no statistically significant differences between the nine sampling points from the point of view of the sampling sites, climate conditions and wind directions. We found no correlation with car traffic, in terms of the number of vehicles, and metals. The values of iron tended to be higher in the areas farther away from the foundry site in the areas located along the path of the prevailing winds. PMID:17637476

Polizzi, Salvatore; Ferrara, Mauro; Bugiani, Massimiliano; Barbero, Domenico; Baccolo, Tiziana

2007-06-12

146

Incorporation of zirconia nanoparticles into coatings formed on aluminium by AC plasma electrolytic oxidation  

Microsoft Academic Search

Composite ceramic coatings were formed on aluminium by AC plasma electrolytic oxidation (PEO) using Na6P6O18 or Na2SiO3 · 5H2O\\/KOH electrolytes with monoclinic zirconia nanoparticles in suspension. The coatings grown in Na2SiO3 · 5H2O\\/KOH electrolyte revealed ?-Al2O3 and amorphous phase; ?-Al2O3 and AlPO4 were additionally produced with the Na6P6O18 electrolyte. Higher temperature zirconia phases, possibly tetragonal and orthorhombic, in addition to the monoclinic phase,\\u000a were

E. Matykina; R. Arrabal; P. Skeldon; G. E. Thompson

2008-01-01

147

Food additives.  

PubMed

The use of additives to food fulfils many purposes, as shown by the index issued by the Codex Committee on Food Additives: Acids, bases and salts; Preservatives, Antioxidants and antioxidant synergists; Anticaking agents; Colours; Emulfifiers; Thickening agents; Flour-treatment agents; Extraction solvents; Carrier solvents; Flavours (synthetic); Flavour enhancers; Non-nutritive sweeteners; Processing aids; Enzyme preparations. Many additives occur naturally in foods, but this does not exclude toxicity at higher levels. Some food additives are nutrients, or even essential nutritents, e.g. NaCl. Examples are known of food additives causing toxicity in man even when used according to regulations, e.g. cobalt in beer. In other instances, poisoning has been due to carry-over, e.g. by nitrate in cheese whey - when used for artificial feed for infants. Poisonings also occur as the result of the permitted substance being added at too high levels, by accident or carelessness, e.g. nitrite in fish. Finally, there are examples of hypersensitivity to food additives, e.g. to tartrazine and other food colours. The toxicological evaluation, based on animal feeding studies, may be complicated by impurities, e.g. orthotoluene-sulfonamide in saccharin; by transformation or disappearance of the additive in food processing in storage, e.g. bisulfite in raisins; by reaction products with food constituents, e.g. formation of ethylurethane from diethyl pyrocarbonate; by metabolic transformation products, e.g. formation in the gut of cyclohexylamine from cyclamate. Metabolic end products may differ in experimental animals and in man: guanylic acid and inosinic acid are metabolized to allantoin in the rat but to uric acid in man. The magnitude of the safety margin in man of the Acceptable Daily Intake (ADI) is not identical to the "safety factor" used when calculating the ADI. The symptoms of Chinese Restaurant Syndrome, although not hazardous, furthermore illustrate that the whole ADI cannot always be ingested as a single dose on an empty stomach with impunity. PMID:277126

Berglund, F

1978-01-01

148

Elaboration et caractérisation de gels hybrides à base d'aluminium  

NASA Astrophysics Data System (ADS)

De nouveaux gels hybrides ``organique-inorganique'' à base d'aluminium sont élaborés par voie sol-gel. Le précurseur moléculaire utilisé est le butylate secondaire d'aluminium Al(OBuS)3 dissous dans CCl4, modifié par le propane-1,2-diol, le butane-1,x-diol (x = 2, 3), et le pentane-1,2-diol. Nous avons étudié l'influence des principaux facteurs (nature du solvant, nature et quantité du diol) sur l'obtention des gels monolithiques et transparents. Toutes les préparations sont réalisées sans ajout d'eau. L'étude par RMN MAS 27Al, RMN CP MAS 13C, et par spectroscopie IR montre qu'une réaction d'échange a lieu entre les groupements OBus de l'alcoxyde d'aluminium et les diols utilisés. Les gels obtenussont monolithiques et transparents, les atomes d'aluminium y sont liés entre eux par des ponts organiques selon la formule -Al-O-R -O-Al- où R est une chaîne hydrocarbonée provenant du diol. This paper presents an original method for elaboration of gels with mixed organic-inorganic networks of the general formula -Al-O-R-O-Al-, with R being a hydrocarbon chain. Starting materials used are aluminum tri-sec-butoxide Al(O-sec-C4H9)3, propane-1,2-diol, butane-1,2-diol, butane-1,3-diol, and pentane-1,2-diol. The reactions were carried out with either CCl4 or cyclohexane as solvent. The exchange reaction between the diols and Al(O-sec-C4H9)3 occurs with the elimination of sec-butanol molecules. Gels are obtained without the addition of water. The monolithic and transparent gels obtained are characterized by IR and as well as 13C and 27Al RMN techniques.

Touati, F.; Gharbi, N.; Zarrouk, H.

1995-11-01

149

The inhibitive effect of some quaternary ammonium salts towards corrosion of aluminium in hydrochloric acid solution  

NASA Astrophysics Data System (ADS)

The inhibitive action of some quaternary ammonium salts towards the corrosion of aluminium in hydrochloric acid was tested by thermometric, mass loss and polarization measurements. Parallelism between the different methods was established. It is suggested that the tested compounds act as cathodic inhibitors. The inhibitors appear to function through adsorption, following the Temkin adsorption isotherm. The values of free energy of adsorption have been calculated and discussed. The inhibitor character of the additives depends upon the concentration as well as the composition of the inhibitor. Within the given homolegous series the contribution of the functional group to adsorption increases with the length of the chain. The aim of this article is to throw some light on the mechanism of inhibition of these bulky molecules on the corrosion of aluminium in hydrochloric acid. L'action inhibitrice de certains sels d'ammonium quaternaires vis-à-vis de la corrosion de l'aluminium dans l'acide chlorhydrique en solution a été testée par des mesures thermiques de perte de matière et de polarisation. Il est suggéré que les composés testés agissent comme des inhibiteurs cathodiques, fonctionnant par adsorption suivant l'isotherme de Temkin. Les énergies libres d'adsorption ont été calculées et discutées. Le caractère inhibiteur des additifs dépend aussi bien de leur concentration que de leur composition. Pour une série d'inhibiteurs homologues, la contribution à l'adsorption du groupe fonctionnel augmente avec la longueur de la chaîne. Le but de cet article est de mieux comprendre le mécanisme d'inhibition de ces grosses molécules sur la corrosion de l'aluminium dans l'acide chlorhydrique.

Mohamed, A.-M. K.; Al-Nadjm, A.; Fouda, A.-A. S.

1998-10-01

150

[Determination of beryllium in atmospheric particulate by graphite furnace atomic absorption spectrophotometer using aluminium as a matrix modifier agent sampling with micropore filter membrane].  

PubMed

Beryllium in the atmospheric particulates is collected with 0.22 micron pore diameter micropore filter membrane, which is determined by graphite furnace atomic absorption spectrophotometer using aluminium as a matrix modifier agent. This sampling method shown several advantages: easy, complete and fast digestion; low membrane blank; high elution recovery, standard addition recovery, precision and accuracy. The addition of 800 mg.L-1 aluminium to beryllium solution allows ashing temperature of 2,000 degrees C. The detection limit of 13.5 ng was obtained. PMID:12945289

Wang, Z; Zhu, W; Lu, Y

2001-08-01

151

DNA Strand Patterns on Aluminium Thin Films  

PubMed Central

A new patterning method using Deoxyribose Nucleic Acid (DNA) strands capable of producing nanogaps of less than 100 nm is proposed and investigated in this work. DNA strands from Bosenbergia rotunda were used as the fundamental element in patterning DNA on thin films of aluminium (Al) metal without the need for any lithographic techniques. The DNA strands were applied in buffer solutions onto thin films of Al on silicon (Si) and the chemical interactions between the DNA strands and Al creates nanometer scale arbitrary patterning by direct transfer of the DNA strands onto the substrate. This simple and cost-effective method can be utilized in the fabrication of various components in electronic chips for microelectronics and Nano Electronic Mechanical System (NEMS) applications in general.

Khatir, Nadia Mahmoudi; Banihashemian, Seyedeh Maryam; Periasamy, Vengadesh; Majid, Wan Haliza Abd; Rahman, Saadah Abdul; Shahhosseini, Fatemeh

2011-01-01

152

Respiratory disorders in aluminium potroom workers.  

PubMed

Epidemiological studies of aluminum potroom workers have been in progress in Norway since 1986. The occurrence of work-related asthmatic symptoms and their determinants were studied. Work-related asthmatic symptoms and airflow limitation were closely associated with duration of potroom employment. A significant relationship between current fluoride exposure and work-related asthmatic symptoms was observed in a smaller, cross-sectional population where a detailed exposure classification was carried out. A similar association and also a dose-response gradient was found in a longitudinal study of new employees. The existence of occupational asthma in aluminium potroom workers was confirmed by characteristic patterns of repeated peak flow measurements supported by changes in methacholine responsiveness in workers with suspected work-related asthma. Current smoking as a risk factor for work-related asthmatic symptoms was observed both in cross-sectional and in longitudinal investigations. Similarly to current fluoride exposure, a dose-response gradient was demonstrated in the association between work-related asthmatic symptoms and current amount of tobacco smoked. Allergy was not shown to be a determinant of work-related asthmatic symptoms in any part of the investigation. A family history of asthma and previous occupational exposure may have had some influence on the risk of developing symptoms but the findings were inconsistent and probably of minor importance. Methacholine challenge seemed inappropriate for the screening of aluminium potroom workers in order to detect work-related asthmatic symptoms, but was closely correlated to the severity of symptoms.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1297049

Kongerud, J

153

Multifunctional additives  

Microsoft Academic Search

A lubricant composition is described comprising a major proportion of an oil of lubricating viscosity or grease or other solid lubricant prepared therefrom and a minor effective proportion of a multifunctional friction reducing\\/high temperature stabilizing additive compound consisting of a Câ to Cââ hydrocarbyl triamine borate adduct or mixtures thereof.

A. G. Horodysky; J. M. Kaminski; H. Ashjian; H. A. Gawel

1986-01-01

154

Color Addition  

NSDL National Science Digital Library

This activity is inquiry in that students do not know how colors are combined. They likely think that the primary colors are red, yellow, and blue. In fact, there are two sets of primary colors: red, green, and blue for additive colors of light, and cyan,

Horton, Michael

2009-05-30

155

Vector Addition  

NSDL National Science Digital Library

This 2D applet simulates vector addition geometrically. The user selects the angle and magnitude of two vectors, which are then added together by the applet. The resultant vector and the values of its magnitude and angle, as well as the values of the x and y components of all three vectors, are calculated and displayed.

Duffy, Andrew

2004-11-28

156

Addition Machines.  

National Technical Information Service (NTIS)

An addition machine is a computing device with a finite number of registers, limited to the following six types of operations: input to register x; copy register y to register x; add register y to register x; subtract register y from register x; compare r...

R. W. Floyd D. E. Knuth

1989-01-01

157

On the role of twinning in the recrystallization of aluminium  

SciTech Connect

Annealing twins are frequently observed in fcc metals of low or medium stacking fault energy although their occurrence in aluminium is comparatively rare as discussed in the early review of twinning by Cahn. Twins have been observed both in recrystallized and vapor deposited aluminium, which suggests that they may be formed during either recrystallization or grain growth. Little significance was attached to annealing twins in aluminium until an extensive research project in Gittingen into the origin of recrystallization textures produced evidence of extensive twin formation during the early stages of recrystallization of several fcc metals including aluminium. As the twinning generated grains of new orientations, which were often observed to have more favorable orientations for growth than the original recrystallization nuclei, it was proposed that twinning is an important factor in determining recrystallization textures.

Humphreys, F.J.; Ferry, M. [Manchester Materials Science Centre (United Kingdom)

1996-07-01

158

Aluminium alloys in municipal solid waste incineration bottom ash.  

PubMed

With the increasing growth of incineration of household waste, more and more aluminium is retained in municipal solid waste incinerator bottom ash. Therefore recycling of aluminium from bottom ash becomes increasingly important. Previous research suggests that aluminium from different sources is found in different size fractions resulting in different recycling rates. The purpose of this study was to develop analytical and sampling techniques to measure the particle size distribution of individual alloys in bottom ash. In particular, cast aluminium alloys were investigated. Based on the particle size distribution it was computed how well these alloys were recovered in a typical state-of-the-art treatment plant. Assessment of the cast alloy distribution was carried out by wet physical separation processes, as well as chemical methods, X-ray fluorescence analysis and electron microprobe analysis. The results from laboratory analyses showed that cast alloys tend to concentrate in the coarser fractions and therefore are better recovered in bottom ash treatment plants. PMID:19423581

Hu, Yanjun; Rem, Peter

2009-05-07

159

Moving Up To Aluminium: Light, Strong and Profitable  

NSDL National Science Digital Library

In this brochure the European Aluminium Association (EAA) outlines the advantages of aluminum use in road transport. These advantages include environmental, revenue, energy, material composition, recycling, sustainability, and safety.

European Aluminium Association (EAA)

160

Comparison of Efficiency between Poly?aluminium Chloride and Aluminium Sulphate Coagulants during Full?scale Experiments in a Drinking Water Treatment Plant  

Microsoft Academic Search

The efficiency of poly?aluminium chloride (PACl) and of aluminium sulphate (alum), two commonly applied coagulant agents, was studied comparatively in this work, during full?scale experiments in a drinking water treatment plant. The removal of suspended solids (turbidity) and the residual aluminium concentrations were carefully monitored and they were used for the evaluation of effectiveness for each coagulant, as well as

A. Zouboulis; G. Traskas; P. Samaras

2008-01-01

161

Fretting wear in self-piercing riveted aluminium alloy sheet  

Microsoft Academic Search

Fretting wear in aluminium alloy AA5754 joined by self-pierce riveting (SPR), a relatively new fastening technique increasingly used in vehicle structures, has been investigated in this paper. Surface damages have been induced when a joint experienced a sinusoidal cyclic tension–tension load. Various degradation zones have been characterised in the contact surfaces between the aluminium sheets, as well as the rivet

Y. K. Chen; L. Han; A. Chrysanthou; J. M O’Sullivan

2003-01-01

162

Reactively sputtered aluminium nitride films for spectral emission control  

Microsoft Academic Search

Aluminium nitride films, 0.8-1.8 mum thick, have been deposited by reactive, magnetron sputtring of aluminium in an argon-nitrogen atmosphere. The sputtered films exhibit a Reststrahlen band in the wavelength range 11-16 mum. We have investigated the possibilities to use different substrate materials and dielectric coatings to extend this interval to the entire upper thermal window 8-13 mum and a secondary

S. Zhao; C.-G. Ribbing

2008-01-01

163

Composites of aluminium alloys: fabrication and wear behaviour  

Microsoft Academic Search

In this paper processes for fabrication of aluminium-alloy composites containing paniculate non-metals, the net shape forming of these composites, their microstructures, their friction and wear behaviours and their mechanical properties are described. Composites of two wrought (2014 and 2024) and one cast (201) aluminium alloys containing 2 to 30 wt% of Al2O3 and SiC particles in the size range of

F. M. Hosking; F. Folgar Portillo; R. Wunderlin; R. Mehrabian

1982-01-01

164

Curcumin attenuates aluminium-induced functional neurotoxicity in rats  

Microsoft Academic Search

Curcumin is a polyphenol extracted from the rhizome of Curcuma longa and well known as a multi-functional drug with antioxidative, anti-cancerous and anti-inflammatory activities. Curcumin's antiageing and neuroprotective potential is widely reported. In the present study, effect of curcumin treatment dose 30 mg kg?1 day?1 was investigated against aluminium neurotoxicity in young and old animals. Direct and indirect intakes of aluminium

Pallavi Sethi; Amar Jyoti; Ejaz Hussain; Deepak Sharma

2009-01-01

165

Joining of aluminium and copper materials with friction welding  

Microsoft Academic Search

Industrial use of non-ferrous materials is significant in the electrical and the chemical engineering applications. Copper–aluminium\\u000a joints are inevitable for certain applications due to unique performances such as higher electric conductivity, heat conductivity,\\u000a corrosion resistance and mechanical properties. Friction welding is the most common method used due to material and energy\\u000a saving. In the present study, copper and aluminium materials

Mumin Sahin

2010-01-01

166

Optimum process parameters for ultrasonic consolidation of 3003 aluminium  

Microsoft Academic Search

In this paper, the ultrasonic consolidation (UC) process is presented for the direct fabrication of monolithic aluminium tooling and components. UC is a solid-state process that involves the use of high frequency, low amplitude, mechanical vibrations to bond metal foils in a layer-by-layer method. The work, described in this paper, centres on the characterisation of aluminium 3003 foils that will

C. Y Kong; R. C Soar; P. M Dickens

2004-01-01

167

Modelling and Validation of Springback in Aluminium U-Profiles  

Microsoft Academic Search

In the current climate of reducing carbon emissions, aluminium alloys have gained popularity for use in automotive structures\\u000a and panels. However, an inherent problem with the higher strength aluminium alloys is the amount of springback that is observed\\u000a on forming, and the relative difficulty of accurately predicting this phenomenon. One of the aims of the Premium Vehicle Lightweight\\u000a Technology (PVLT)

M. Stanton; I. Masters; R. Bhattacharya; I. Dargue; R. Aylmore; G. Williams

2010-01-01

168

Microstructure, tensile deformation and fracture behaviour of aluminium alloy 7055  

Microsoft Academic Search

The microstructure, tensile deformation and fracture behaviour of aluminium alloy 7055 were studied. Detailed optical and\\u000a electron microscopy observations were made to analyse the as-received microstructure of the alloy. Detailed transmission electron\\u000a microscopy observations revealed the principal strengthening precipitates to be the hexagonal disc-shaped ?? phase of size\\u000a 2 mm20 mm and fully coherent with the aluminium alloy matrix, the

T. S Srivatsan; S. SRIRAM; D Veeraraghavan; V. K Vasudevan

1997-01-01

169

Theoretical modelling of porous oxide growth on aluminium  

Microsoft Academic Search

A theoretical model for porous structure formation during electrochemical anodization of aluminium is developed taking into account anodic oxide growth at the oxide\\/electrolyte and oxide\\/aluminium interfaces, electrochemical and field-enhanced oxide dissolution, and a three-dimensional configuration of electric field and current in the scalloped barrier oxide layer at pore bottoms. A system of equations ensuring a general description of the porous

V. P. Parkhutik; V. I. Shershulsky

1992-01-01

170

Effects of aqueous aluminium on four fish ectoparasites  

Microsoft Academic Search

Effects of aqueous aluminium on four species of fish ectoparasites were studied. Fish infected by Gyrodactylus derjavini, G. macronychus and Anodonta anatina glochidia, and free living Argulus foliaceus were exposed to acidic Al-rich water (pH 5.8), acidic Al-poor water (pH 5.8) and control water (pH 6.3). The results showed that aqueous aluminium had a negative effect on the ectoparasites tested,

Ruben A. Pettersen; L. Asbjørn Vøllestad; Lars E. W. Flodmark; Antonio B. S. Poléo

2006-01-01

171

Residual stresses in aluminium alloy friction stir welds  

Microsoft Academic Search

Residual stresses are detrimental to the fatigue, fracture and corrosion resistance of welds. The literature on residual stress\\u000a measurements in aluminium alloy friction stir welds is reviewed. The results of a large number of longitudinal residual stress\\u000a measurements performed by the slitting method on friction stir welds in 2024-T3, 6082-T6 and 5754-H111 aluminium alloys are\\u000a compared and their origin discussed.

Kevin Deplus; Aude Simar; Wim Van Haver; Bruno de Meester

172

Absolutely Addition  

NSDL National Science Digital Library

Here are some fun games and activities to help with understanding and using addition. NUMBER LINE PRACTICE Begin with this fun game Line Jumper. Click on the medium level and complete all ten number line problems. When finished close the window and return to complete the next assignment. MR. BEAR\\'S CLOSET In this exciting activiy, Mr. Bear can\\'t decide what to wear. Can you help him? ...

Korth, Mrs.

2005-03-23

173

Dynamics of colliding aluminium plasmas produced by laser ablation  

NASA Astrophysics Data System (ADS)

The collision of two aluminium plasmas was investigated by combining both time and space resolved spectroscopy and Langmuir probe measurements. Plasma plumes were produced by a Continuum™ Surelite Nd:YAG Laser System with pulse duration of FWHM of 6 ns and wavelength of 1064 nm, at a laser irradiance of 1011 W/cm2 on slab Al targets. By analyzing the emission spectra, the temporally and spatially resolved electron density and electron temperature at the stagnation layer were extracted, with a time resolution of 10 ns. Data analysis confirms that the electron density of the stagnation layer evolves over a longer timescale than in the single plume case. On the other hand, the temperature trends show that the electron temperature decreases much more rapidly at the stagnation layer than in the case for the single expanding plasma. In addition, a Langmuir probe was used to investigate the properties of the collisional front evolution. The overall experimental results show that colliding laser produced plasmas could be useful in the design of experiments devoted to fusion reaction rate measurements in a low energy domain by including the effect of the electron screening (ES).

Gambino, N.; Hayden, P.; Mascali, D.; Costello, J.; Fallon, C.; Hough, P.; Yeates, P.; Anzalone, A.; Musumeci, F.; Tudisco, S.

2013-05-01

174

Modelling of Local Necking and Fracture in Aluminium Alloys  

NASA Astrophysics Data System (ADS)

Non-linear Finite Element simulations are extensively used in forming and crashworthiness studies of automotive components and structures in which fracture need to be controlled. For thin-walled ductile materials, the fracture-related phenomena that must be properly represented are thinning instability, ductile fracture and through-thickness shear instability. Proper representation of the fracture process relies on the accuracy of constitutive and fracture models and their parameters that need to be calibrated through well defined experiments. The present study focuses on local necking and fracture which is of high industrial importance, and uses a phenomenological criterion for modelling fracture in aluminium alloys. As an accurate description of plastic anisotropy is important, advanced phenomenological constitutive equations based on the yield criterion YLD2000/YLD2003 are used. Uniaxial tensile tests and disc compression tests are performed for identification of the constitutive model parameters. Ductile fracture is described by the Cockcroft-Latham fracture criterion and an in-plane shear tests is performed to identify the fracture parameter. The reason is that in a well designed in-plane shear test no thinning instability should occur and it thus gives more direct information about the phenomenon of ductile fracture. Numerical simulations have been performed using a user-defined material model implemented in the general-purpose non-linear FE code LS-DYNA. The applicability of the model is demonstrated by correlating the predicted and experimental response in the in-plane shear tests and additional plane strain tension tests.

Achani, D.; Eriksson, M.; Hopperstad, O. S.; Lademo, O.-G.

2007-05-01

175

Modelling of Local Necking and Fracture in Aluminium Alloys  

SciTech Connect

Non-linear Finite Element simulations are extensively used in forming and crashworthiness studies of automotive components and structures in which fracture need to be controlled. For thin-walled ductile materials, the fracture-related phenomena that must be properly represented are thinning instability, ductile fracture and through-thickness shear instability. Proper representation of the fracture process relies on the accuracy of constitutive and fracture models and their parameters that need to be calibrated through well defined experiments. The present study focuses on local necking and fracture which is of high industrial importance, and uses a phenomenological criterion for modelling fracture in aluminium alloys. As an accurate description of plastic anisotropy is important, advanced phenomenological constitutive equations based on the yield criterion YLD2000/YLD2003 are used. Uniaxial tensile tests and disc compression tests are performed for identification of the constitutive model parameters. Ductile fracture is described by the Cockcroft-Latham fracture criterion and an in-plane shear tests is performed to identify the fracture parameter. The reason is that in a well designed in-plane shear test no thinning instability should occur and it thus gives more direct information about the phenomenon of ductile fracture. Numerical simulations have been performed using a user-defined material model implemented in the general-purpose non-linear FE code LS-DYNA. The applicability of the model is demonstrated by correlating the predicted and experimental response in the in-plane shear tests and additional plane strain tension tests.

Achani, D. [Structural Design, Offshore Construction Engineering, SUBSEA7, NO-4056 Tananger (Norway); Eriksson, M. [SINTEF Materials and chemistry, Applied mechanics and corrosion, NO-7465 Trondheim (Norway); Hopperstad, O. S. [SIMLab, Department of Structural Engineering, Norwegian University of Science and Technology, NO-7491 Trondheim (Norway); Lademo, O.-G. [SINTEF Materials and chemistry, Applied mechanics and corrosion, NO-7465 Trondheim (Norway); SIMLab, Department of Structural Engineering, Norwegian University of Science and Technology, NO-7491 Trondheim (Norway)

2007-05-17

176

Bond strength and interfacial structure of silicon nitride joints brazed with aluminium-silicon and aluminium-magnesium alloys  

Microsoft Academic Search

From the results of the bending strength and Weibull modulus of the joints of silicon nitride ceramics brazed using aluminium-silicon and aluminium-magnesium alloy filler metals at a temperature of 1073 K for 0.9 ksec in a vacuum of 1.3 × 10-3 Pa, silicon, especially, present in a small amount in the filler metals, was found to be effective in improving

X. S. Ning; T. Okamoto; Y. Miyamoto; A. Koreeda; K. Suganuma; S. Goda

1991-01-01

177

The Effect of Zinc to Aluminium Molar Ratio on the Formation of ZINC-ALUMINIUM-4-CHLOROPHENOXYACETATE Nanocomposite  

NASA Astrophysics Data System (ADS)

Layered organic-inorganic hybrid nanocomposite material containing 4-chlorophenoxy acetate, (4CPA) intercalated into zinc-aluminium-layered double hydroxide (ZAL) was prepared by direct self-assembly method for the formation of Zn-Al-4CPA nanocomposite (ZAC). Various Zn2+ to Al3+ molar ratios, R ranging from 1 to 6 were used in the preparation of the mother liquor with fixed concentration of 4CPA at 0.4 M. The pH of the solution was adjusted to 7.5 by slow addition of 2 M NaOH. Well-ordered nanolayered organic-inorganic hybrid nanocomposites with the expansion of basal spacing from 8.9 A? in the layered double hydroxide to 19.1-21.2 A? in the resulting nanocomposites were obtained. The FTIR spectra for the nanocomposites showed that the spectrum composed of spectral features of ZAL and 4CPA showing the successful intercalation of the organic moiety into the LDH interlayer. The BET surface area decreased as the XAl value increased while the percentage loading of 4CPA in the nanocomposites increased in the range of 38.9-44.7 % (w/w) as the XAl increased. This shows that the mole ratio of Zn2+ to Al3+, R in the mother liquor controlled the physicochemical properties of the resulting nanocomposite, Zn-Al-4CPA.

Sarijo, Siti Halimah; Hussein, Mohd. Zobir; Zainal, Zulkarnain; Yahaya, Asmah Hj.

2009-06-01

178

The role of root exudates in aluminium resistance and silicon-induced amelioration of aluminium toxicity in three varieties of maize (Zea mays L.).  

PubMed

Aluminium (Al) toxicity is widely considered to be the most important growth-limiting factor for plants in strongly acid soils (pH<5.0). The inhibition of root elongation in three varieties of maize (Zea mays L. vars Clavito, HS701b and Sikuani) was followed over the first 48 h of Al treatment, and during the initial 10 h elongation was determined on an hourly basis. The silicon (Si)-induced amelioration of Al toxicity was investigated by pre-treating seedlings for 72 h in nutrient solutions with 1000 microM Si before transfer into solutions with 0, 20 or 50 microM Al (without Si). Plants were either grown in complete low ionic strength nutrient solutions (CNS) or in low salt solutions of 0.4 mM CaCl2 (LSS). In addition, the role of root exudation of organic compounds as a mechanism of Si-induced alleviation of Al toxicity was investigated. Aluminium-induced inhibition of root elongation in the maize var. HS701b was observed within 1 h of Al exposure. After a lag time of at least 8 h, Si-induced alleviation of Al toxicity was observed in this variety when grown in LSS. In the Al-resistant var. Sikuani, Al-resistance was only observed after exposure to 50 microM Al, and not after exposure to 20 microM Al, suggesting that there exists a threshold Al concentration before the mechanisms of Al resistance are activated. Aluminium stimulated root exudation of oxalic acid in all three varieties, but exudate concentrations did not increase with either Al resistance or with Si pretreatment. Aluminium and Si triggered release of catechol and of the flavonoid-type phenolics: catechin, and quercetin. In the Al-resistant variety, Sikuani, Al-exposed plants pretreated with Si exuded up to 15 times more phenolics than those plants not pretreated with Si. The flavonoid-type phenolics, to date unconsidered, appear to play a role in the mechanism(s) of Si-induced amelioration of Al toxicity. PMID:11432953

Kidd, P S; Llugany, M; Poschenrieder, C; Gunsé, B; Barceló, J

2001-06-01

179

Identifying Surface Angled Cracks on Aluminium Bar Using Emats and Automated Computer System  

NASA Astrophysics Data System (ADS)

Electromagnetic acoustic transducers (EMATs) have been used to generate and detect Rayleigh waves in order to identify surface cracking in aluminium bars and rails. B-scans produced during scans of samples were used to determine the presence of surface defects. Additionally, the differences between signal enhancements due to wave interference at the crack produced by normal (90°) and angled cracks in the B-scans were used to classify samples in order to decide an appropriate depth calibration curve for depth estimation. Classification was done using an image processing algorithm that selected the best features for classification, and used these to identify similar patterns in unclassified B-scans.

Rosli, M. H.; Edwards, R. S.; Dutton, B.; Johnson, C. G.; Cattani, P. T.

2010-02-01

180

Fluorescence reaction and complexation equilibria between norfloxacin and aluminium (III) ion in chloride medium  

Microsoft Academic Search

Norfloxacin, 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinoline carboxylic acid (NORH), reacts with aluminium(III) ion forming the strongly fluorescent complex [Al(HNOR)]3+, in slightly acidic medium. The complex shows maximum emission at 440 nm with excitation at 320 nm. The fluorescence intensity is enhanced upon addition of 0.5% sodium dodecylsulphate. Fluorescence properties of the Al-NOR complex were used for the direct determination of trace amounts of NOR

Predrag T. Djurdjevic; Milena Jelikic-Stankov; Dejan Stankov

1995-01-01

181

Effect of Excess SiO 2 on the Reaction Sintering of Aluminium Titanate–25 vol% Mullite Composites  

Microsoft Academic Search

A stepwise alkoxide hydrolysis processing was used to prepare aluminium titanate–25vol% mullite composite powders. The effect of three levels of excess SiO2 (1, 3 and 5wt%, expressed relative to Al2TiO5) on densification, microstructure, mechanical strength and thermal expansion has been investigated. The addition of excess SiO2 reduced the constrained effect caused by the formation of Al2TiO5 and mullite. After the

Y. X Huang; A. M. R Senos; J. L Baptista

1998-01-01

182

Inhibition of methanogenesis by interaction of aluminium ion with co-factor, F-420, in Methanosarcina barkeri.  

PubMed

Methane emission was inhibited by aluminium ion in paddy fields. Addition of Al3+ (20 mM) to the culture medium containing cells of pure Methanosarcina barkeri, inhibited methanogenesis. Methanogenic co-factor, F-420, was isolated and purified from Methanosarcina barkeri MS. Spectrophotometric and spectrofluorometric analysis of interaction between co-factor, F-420, and Al3+ revealed that they formed a complex compound that might have blocked methanogenesis. PMID:15248497

Chattopadhyay, B D; Thakur, A R

2003-08-01

183

A systematic review of aluminium phosphide poisoning.  

PubMed

Every year, about 300,000 people die because of pesticide poisoning worldwide. The most common pesticide agents are organophosphates and phosphides, aluminium phosphide (AlP) in particular. AlP is known as a suicide poison that can easily be bought and has no effective antidote. Its toxicity results from the release of phosphine gas as the tablet gets into contact with moisture. Phosphine gas primarily affects the heart, lungs, gastrointestinal tract, and kidneys. Poisoning signs and symptoms include nausea, vomiting, restlessness, abdominal pain, palpitation, refractory shock, cardiac arrhythmias, pulmonary oedema, dyspnoea, cyanosis, and sensory alterations. Diagnosis is based on clinical suspicion, positive silver nitrate paper test to phosphine, and gastric aspirate and viscera biochemistry. Treatment includes early gastric lavage with potassium permanganate or a combination with coconut oil and sodium bicarbonate, administration of charcoal, and palliative care. Specific therapy includes intravenous magnesium sulphate and oral coconut oil. Moreover, acidosis can be treated with early intravenous administration of sodium bicarbonate, cardiogenic shock with fluid, vasopresor, and refractory cardiogenic shock with intra-aortic baloon pump or digoxin. Trimetazidine may also have a useful role in the treatment, because it can stop ventricular ectopic beats and bigeminy and preserve oxidative metabolism. This article reviews the epidemiological, toxicological, and clinical/pathological aspects of AlP poisoning and its management. PMID:22450207

Mehrpour, Omid; Jafarzadeh, Mostafa; Abdollahi, Mohammad

2012-03-01

184

Influence of nanoporous structure on mechanical strength of aluminium and aluminium alloy adhesive structural joints  

NASA Astrophysics Data System (ADS)

The influence of surface treatments on the mechanical strength of adhesive joints was investigated. The attention was focused on AA2024 alloy because it is extensively used in both the automotive and aerospace industries. Adhesive joints fabricated with pure aluminium were also investigated in order to evidence possible differences in the surface features after identical treatments. Before joining with a commercial epoxy adhesive, metal substrates were subjected to different kinds of treatment and the surfaces were characterized by SEM analysis. The formation of a microporous surface in the AA2024 alloy, upon etching and anodizing, is discussed on the basis of the role of the intermetallic particles and their electrochemical behaviour with respect to the aluminium matrix. Moreover, nanostructured porous oxide layers on both type of substrate were also formed, as a consequence of the anodizing process. Differences in their morphologies were revealed as a function of both the applied voltage and the presence of alloying elements. On this basis, an explanation of the different values of fracture energy measured by means of T-peel tests carried out on the corresponding joints was attempted.

Spadaro, C.; Dispenza, C.; Sunseri, C.

2006-08-01

185

Effects of aqueous aluminium on four fish ectoparasites.  

PubMed

Effects of aqueous aluminium on four species of fish ectoparasites were studied. Fish infected by Gyrodactylus derjavini, G. macronychus and Anodonta anatina glochidia, and free living Argulus foliaceus were exposed to acidic Al-rich water (pH 5.8), acidic Al-poor water (pH 5.8) and control water (pH 6.3). The results showed that aqueous aluminium had a negative effect on the ectoparasites tested, without any apparent negative effect on the fish hosts. The effect of aluminium was dependent on the kind of organism tested. The gyrodactylids were eliminated, while the duck mussel glochidia showed a decrease in abundance when exposed to 200-260 mug Al/l at pH 5.8. The little fish louse showed increased mortality rate when exposed to aluminium. The effects of aluminium on the parasites in the present study confirm the importance of water quality in general, and acidification in particular, for the distribution and population dynamics of ectoparasites in freshwater environments. PMID:16904736

Pettersen, Ruben A; Vøllestad, L Asbjørn; Flodmark, Lars E W; Poléo, Antonio B S

2006-08-14

186

Computer modelling of age hardening for cast aluminium alloys  

NASA Astrophysics Data System (ADS)

Age hardening, or precipitation hardening, is one of the most widely adopted techniques for strengthening of aluminium alloys. Although various age hardening models have been developed for aluminium alloys, from the large volume of literature reviewed, it appears that the bulk of the research has been concentrated on wrought aluminium alloys, only a few of the established precipitation models have been applied to the casting aluminium alloys. In the present work, there are two modelling methods that have been developed and applied to the casting aluminium alloys A356 and A357. One is based on the Shercliff-Ashby methodology to produce a process model, by which we mean a mathematical relationship between process variables (alloy composition, ageing temperature and time) and material properties (yield strength or hardness) through microstructure evolution (precipitate radius, volume fraction). The other method is based on the Kampmann and Wagner Numerical (KWN) model which deals with concomitant nucleation, growth and coarsening and is thus capable of predicting the full evolution of the particle size distribution and then a strength model is used to evaluate the resulting change in hardness or yield strength at room temperature by taking into account contributions from lattice resistance, solid solution hardening and precipitation hardening.

Wu, Linda; Ferguson, W. George

2009-08-01

187

Aluminium dust-air detonation at elevated pressures  

NASA Astrophysics Data System (ADS)

Understanding the detonability of aluminium particles suspended in air at elevated pressures is important in problems associated with industrial safety, stagnation flow, or shocked flow conditions. While micrometric aluminium dust-air detonation at atmospheric conditions is feasible in large tubes using a strong initiation source [1-4], the detonation properties and structure at elevated pressures have not been carefully investigated. For organic dust with a high volatile content, the detonation sensitivity is increased with increasing initial pressure, approximately following the scaling rule of gaseous detonations in which the detonation cell size is inversely proportional to initial pressure [4-5]. However, aluminium particles possess an oxide layer that has a high melting temperature, thus increasing the difficulty of detonation initiation and the understanding of the detonation mechanism. The aim of the present paper is to study the influence of elevated initial pressures on the detonation properties and structure in aluminium dust-air mixtures. To understand the scaling effect of particle size, experiments were carried out for a nanometric and a micrometric aluminium particle size at various particle concentrations.

Zhang, F.; Murray, S. B.; Gerrard, K. B.

188

Comparative Effects of Several Chelating Agents on the Toxicity, Distribution and Excretion of Aluminium  

Microsoft Academic Search

The relative efficacy of citric, malic, malonic, oxalic and succinic acids, and deferoxamine mesylate (DFOA) on the toxicity, distribution and excretion in mice exposed to aluminium were compared. Chelating agents were administered intraperitoneally at a dose equal to one-fourth of their respective LD50. To determine the effect of the various chelators on the toxicity of aluminium, various doses of aluminium

J. L. Domingo; M. Gómez; J. M. Llobet; J. Corbella

1988-01-01

189

Preparation and properties of cast aluminium alloy-granite particle composites  

Microsoft Academic Search

With a view to develop light weight, low cost and abrasion resistant material cast aluminium alloy composites dispersed with granite particles were prepared and their properties were evaluated. Natural mineral granite was crushed and treated prior to its incorporation in the aluminium alloy. Liquid metallurgy techniques was used to prepare composites involving the following steps: melting of aluminium alloy in

M. Singh; A. K. Jha; S. Das; A. H. Yegneswaran

2000-01-01

190

Effect of current wave-form on AC TIG welding of aluminium alloys  

Microsoft Academic Search

Because of their superior properties (low specific gravity, corrosion resistance, recyclability etc.), aluminium alloys are currently employed in various sectors and their applications are still expanding. It is well-known that it is necessary to eliminate the oxide film formed on the aluminium alloy surface prior to welding, this characterises the welding of aluminium alloys.

F. Miyasaka; T. Okuda; T. Ohji

2005-01-01

191

Effects of aluminium salts on bone marrow chromosomes in rats in vivo.  

PubMed

Oral administration of aluminium sulphate to laboratory bred Rattus norvegicus for prolonged period induced dose dependent inhibition of dividing cells and an increase in chromosomal aberrations. The effect was not influenced by the duration of exposure. The toxicity of the two salts, aluminium sulphate and potassium aluminium sulphate, did not differ significantly at doses in which the metal contents were kept constant. PMID:1868749

Roy, A K; Sharma, A; Talukder, G

1991-01-01

192

Hexachlorobenzene and octachlorostyrene in plasma of aluminium foundry workers using hexachloroethane for degassing  

Microsoft Academic Search

OBJECTIVES: To study the load of selected organochlorine compounds in the blood of aluminium foundry workers who use hexachloroethane as a degassing agent for aluminium and to measure some possible effects on internal organs. METHODS: Plasma from nine male aluminium foundry workers with past experience of use of hexachloroethane and 18 controls (two controls per exposed case) matched for residence,

A I Seldén; Y Nygren; H B Westberg; L S Bodin

1997-01-01

193

Applicability of constant dew point corrosion tests for evaluating atmospheric corrosion of aluminium alloys  

Microsoft Academic Search

Field exposure tests of aluminium alloys were conducted at three sites in Japan. Meteorological data indicated that the dew point of the ambient atmosphere and aluminium panels remained constant for the short-term. Constant dew point corrosion tests were employed to reproduce atmospheric corrosion of aluminium alloys in the laboratory. The corrosion rates, corrosion morphology and corrosion product composition after 7days

Zhenhua Dan; Shunsuke Takigawa; Izumi Muto; Nobuyoshi Hara

2011-01-01

194

Amino and polyamino acids as corrosion inhibitors for aluminium and zinc pigments  

Microsoft Academic Search

A severe problem with water-borne paints containing aluminium or zinc pigments is hydrogen corrosion of these metals in the aqueous alkaline paint media. The subject of the present study is the examination of corrosion inhibition of aluminium and zinc pigments in aqueous alkaline media by different amino and polyamino acids. Aspartic acid inhibits this corrosion reaction of aluminium pigment only

Bodo Müller

2002-01-01

195

Modelling the material flow of recycling processes for aluminium alloys by means of technical recycling quotas  

Microsoft Academic Search

The amount of aluminium alloys used for different applications such as cars, packaging or buildings has risen considerably during the past 20 years. This will effect a growing amount of scrap being available for recycling in the future. The special properties of the metal aluminium require sophisticated processing of different types of aluminium containing material prior to re-melting and refining.

H. Hoberg; S. Wolf; J. Meier-Kortwig

196

Surface chemical studies of anodically oxidised aluminium membranes  

NASA Astrophysics Data System (ADS)

X-ray photoelectron spectroscopy (XPS) and fast atom bombardment secondary ion mass spectrometry (FAB-SIMS) have been used to study the surfaces of inorganic microfiltration membranes produced by controlled removal of anodic films formed on aluminium in phosphoric and oxalic acid electrolytes. The results are compared with those of similar analyses of membranes produced from anodic films formed in mixed oxalic/phosphoric acid electrolyte. Both techniques established that phosphates were concentrated on the surface of membranes formed in phosphoric acid and oxalic/phosphoric acid and that oxalate ions were present on the surfaces of membranes formed in oxalic acid. The low intensity of the AlO -x fragments implies that all of the aluminium ions in the surface are coordinated to phosphates or oxalates. However, any differences its the chemical state of the aluminium on the different membranes were not detectable by either technique.

Treverton, J. A.; West, R.; Johnson, D.; Thornton, M.

1993-12-01

197

Different Approach to the Aluminium Oxide Topography Characterisation  

SciTech Connect

Different surface topographic techniques are being widely used for quantitative measurements of typical industrial aluminium oxide surfaces. In this research, specific surface of aluminium oxide layer on the offset printing plate has been investigated by using measuring methods which have previously not been used for characterisation of such surfaces. By using two contact instruments and non-contact laser profilometer (LPM) 2D and 3D roughness parameters have been defined. SEM micrographs of the samples were made. Results have shown that aluminium oxide surfaces with the same average roughness value (Ra) and mean roughness depth (Rz) typically used in the printing plate surface characterisation, have dramatically different surface topographies. According to the type of instrument specific roughness parameters should be used for defining the printing plate surfaces. New surface roughness parameters were defined in order to insure detailed characterisation of the printing plates in graphic reproduction process.

Poljacek, Sanja Mahovic; Gojo, Miroslav [Faculty of Graphic Arts, University of Zagreb, Getaldiceva 2, 10000 Zagreb (Croatia); Raos, Pero; Stoic, Antun [Mechanical Engineering Faculty, J.J. Strossmayer University of Osijek, Trg Ivane Brlic Mazuranic 2, 35000 Slavonski Brod (Croatia)

2007-04-07

198

The aluminium content of infant formula and tea  

Microsoft Academic Search

Tea and infant formulae have been examined for the presence of aluminium. Concentrations in 13 different tea infusions ranged from 2.2 mg\\/l to 4.5 mg\\/l. In cows’ milk?based infant formulae as made up for consumption, aluminium levels of between 0.03 mg\\/l and 0.20 mg\\/l were detected. Higher amounts were present in soya?based formulae with concentrations ranging from 0.64 mg\\/l to

M. J. Baxter; J. A. Burrell; R. C. Massey

1990-01-01

199

Towards an understanding of the adjuvant action of aluminium  

PubMed Central

The efficacy of vaccines depends on the presence of an adjuvant in conjunction with the antigen. Of these adjuvants, the ones that contain aluminium, which were first discovered empirically in 1926, are currently the most widely used. However, a detailed understanding of their mechanism of action has only started to be revealed. In this Timeline article, we briefly describe the initial discovery of aluminium adjuvants and discuss historically important advances. We also summarize recent progress in the field and discuss their implications and the remaining questions on how these adjuvants work.

Marrack, Philippa; McKee, Amy S.; Munks, Michael W.

2011-01-01

200

Effects of Aluminium on the compressibility of silicate perovskite  

NASA Astrophysics Data System (ADS)

Among the elements present in all mantle compositional models, aluminium oxide Al2O3 is estimated to amount 4 to 5 mole %. While aluminium is incorporated in specific minerals such as garnet and majorite in the upper mantle, it is believed to be incorporated into (Mg,Fe)SiO3-perovskite under the pressure and temperature conditions of the lower mantle. Recently, the effect of Al on the elastic parameters of perovskite has received extreme attention, since Zhang and Weidner [1] presented for an Al-bearing silicate perovskite a bulk modulus 10% smaller than that of the end-member MgSiO3-perovskite. However, the bulk moduli obtained afterwards at various alumina content were highly scattered. We present here a series of volume measurements up to 40 GPa, for Mg-perovskites with respectively 5, 7.7 and 20 mol % aluminium. Samples were either synthesized in a multi-anvil apparatus or in a diamond anvil cell by laser heating a 20 ?m thin glass slide of the relevant composition. Samples were studied in a diamond anvil cell with neon as a hydrostatic pressure transmitting medium and were annealed with a YAG laser within their pressure stability filed. Angle dispersive diffraction patterns were collected upon compression to the peak pressure and during decompression, at the ID9 dedicated high-pressure beamline of the ESRF. From the various data sets fitted to a Birch-Murnaghan equation of state, we deduce that the the relationship between the bulk modulus of perovskite and the Al content is not a linear decrease. Whereas 5 mol % aluminium has no noticeable effect on the compressibility of silicate perovskite, increasing slightly the aluminium content of perovskite strongly decreases its bulk modulus. Moreover, as the aluminium is added into perovskite, the compression/decompression behaviour of the samples displays different regimes. These results can be related to the substitution mechanism of Al into perovskite, suggesting that the coupled substitution mechanism is probably efficient at low aluminium content, but might then replaced by the oxygen vacancy one at higher aluminium content. This indicates that the investigations of the chemical and petrological compositions of the uppermost lower mantle and of heterogeneities should definitely take into account the effect of Al on the thermoelastic properties of perovskite. This also suggests that the partitioning behaviour of some trace elements between perovskite and the other lower mantle phases might be different in deep subducted lithospheric plates than in the `mean' lower mantle. [1] Zhang, J., and D.J. Weidner,Science,284, 782, 1999.

Daniel, I.; Bass, J. D.; Fiquet, G.; Cardon, H.; Hanfland, M.

2004-12-01

201

Soil aluminium uptake and accumulation by Paspalum notatum.  

PubMed

Paspalum notatum Flugge has been widely utilized for the purpose of ecological restoration of degraded land in the tropics and subtropics, where soil active aluminium (Al) is usually high as a result of acidification. Pot experiments were conducted to determine Al toxicity on P. notatum and to compare its potential to remove Al with another three plant species, Vetiveria zizanioides, Tristania conferta and Schima wallichii. In the Al addition experiment, the biomass of P. notatum and Al accumulation significantly decreased as the added Al concentration increased, but Al concentration in the plant markedly increased. A parallel experiment was conducted with the above four species, grown in lateritic soil and in oil shale waste containing high concentration of active Al. The biomasses of all four species were reduced obviously in the waste compared to in the soil. The effects of substrate on Al concentration, accumulation and translocation efficiency differed among species, and plants had significantly higher Al accumulation factors when grown in the soil than in the waste. Most of the Al taken up by P. notatum was transferred to above-ground parts; as a result, Al concentration in stems and leaves became quite high, over 1000 or even 3000 mg kg(-1); whereas for the other three species, Al concentration in shoots was much lower than in roots. Paspalum notatum was therefore much higher than the other three species with regard to Al translocation efficiency and therefore P. notatum may be regarded as both an effective Al hyper-accumulator and a potential Al hyper-remover. PMID:19423590

Huang, Juan; Xia, Hanping; Li, Zhi'an; Xiong, Yanmei; Kong, Guohui; Huang, Juan

2009-05-07

202

Occupational exposure to beryllium in primary aluminium production.  

PubMed

Alumina used in the production of primary aluminium contains Be which partly vaporises from the cryolite bath into the workroom atmosphere. Since Be may be toxic at lower exposure levels than previously thought, the personal exposure to Be among workers in 7 Norwegian primary smelters has been assessed. In total, 480 personal Respicon® virtual impactor full shift air samples have been collected during 2 sampling campaigns and analysed for water soluble Be, Al and Na using inductively coupled plasma optical emission spectrometry. In addition, water soluble F(-) has been measured by ion chromatography. The Be air concentrations in the inhalable, thoracic and respirable aerosol fractions have been calculated. The Be concentrations in the inhalable aerosol fraction vary between the different smelters. The highest GM concentration of Be in the inhalable fraction (122 ng m(-3), n = 30) was measured in the prebake pot room of a smelter using predominantly Jamaican alumina where also the highest individual air concentration of 270 ng m(-3) of Be was identified. The relative distribution of Be in the different aerosol fractions was fairly constant with the mean Be amount for the two sampling campaigns between 44-49% in the thoracic fraction expressed as % of the inhalable amount. Linear regression analysis shows a high correlation between water soluble Be, Al, F and Na describing an average measured chemical bulk composition of the water soluble thoracic fraction as Na(5.7)Al(3.1)F(18). Be is likely to be present as traces in this particulate matter by replacing Al atoms in the condensed fluorides and/or as a major element in a nanoparticle sized fluoride. Thus, the major amount of Be present in the work room atmosphere of Al smelter pot rooms will predominantly be present in combination with substantial amounts of water soluble Al, F and Na. PMID:21993554

Skaugset, Nils Petter; Ellingsen, Dag G; Dahl, Kari; Martinsen, Ivar; Jordbekken, Lars; Drabløs, Per Arne; Thomassen, Yngvar

2011-10-13

203

Accumulation of Aluminium and Physiological Status of Tree Foliage in the Vicinity of a Large Aluminium Smelter  

PubMed Central

A pollution gradient was observed in tree foliage sampled in the vicinity of a large aluminium production facility in Patagonia (Argentina). Leaves of Eucalyptus rostrata, and Populus hybridus and different needle ages of Pinus spec. were collected and concentrations of aluminium (Al) and sulphur (S) as well as physiological parameters (chlorophyll and lipid oxidation products) were analyzed. Al and S concentrations indicate a steep pollution gradient in the study showing a relationship with the physiological parameters in particular membrane lipid oxidation products. The present study confirms that aluminium smelting results in high Al and sulphur deposition in the study area, and therefore further studies should be carried out taking into account potentially adverse effects of these compounds on human and ecosystem health.

Wannaz, E. D.; Rodriguez, J. H.; Wolfsberger, T.; Carreras, H. A.; Pignata, M. L.; Fangmeier, A.; Franzaring, J.

2012-01-01

204

Microfabrication of an anodic oxide film by anodizing laser-textured aluminium  

NASA Astrophysics Data System (ADS)

A simple method for the fabrication of microstructures of an aluminium anodic oxide film (anodic alumina) by anodizing laser-textured aluminium is demonstrated. In the process, the aluminium substrate was first textured by a low power laser beam, and then the textured aluminium was subjected to anodizing, to develop a continuous, thick porous layer on the textured surface. Microstructures with a depth of a few to several tens of micrometres were fabricated successfully on the anodic oxide film by using various combinations of laser power density and laser scanning speed. Removing the film from the aluminium substrate enables the fabrication of various 2D and 3D microstructures from anodic alumina.

Jha, Himendra; Kikuchi, Tatsuya; Sakairi, Masatoshi; Takahashi, Hideaki

2007-10-01

205

Examples of liquiq metal embrittlement in industrial aluminium alloys  

NASA Astrophysics Data System (ADS)

Liquid metal embrittlement (LME) phenomena were investigated in two industrial aluminium alloys. Gallium penetration in 7010 alloys was systematically investigated to shed light on the effect of microstructure and plasticity ahead of the crack tip. Hot temperature shortness in 5083 alloy is given as an example of cleavage induced by LME.

Bréchet, Y.; Rodine, A.; Véron, M.; Péron, S.; Deschamps, A.

2002-09-01

206

Crash and structural analyses of an aluminium railroad passenger car  

Microsoft Academic Search

Crashworthiness, strength and vibrational features of a railroad passenger car, which is originally made of steel members and then converted to an aluminium design, are studied. The finite element (FE) method is utilised for the static analysis in compliance with various scenarios defined in UIC CODE OR 577, modal analysis and simulation of the crash into a rigid wall. Firstly,

C. Baykasoglu; E. Sunbuloglu; S. E. Bozdag; F. Aruk; T. Toprak; A. Mugan

2012-01-01

207

Thermophysical properties of plasma electrolytic oxide coatings on aluminium  

Microsoft Academic Search

Plasma electrolytic oxide coatings appear to offer attractive combinations of hardness, wear resistance, corrosion resistance and interfacial adhesion. In order to optimise such characteristics, however, more basic thermo-physical property data are required, together with an understanding of how they are affected by processing conditions and microstructure. In the present study, coatings were produced on 6082 aluminium and characterised using profilometry,

J. A. Curran; T. W. ClyneT

2005-01-01

208

Leaching of aluminium from cooking pans and food containers  

Microsoft Academic Search

Aluminium is not an essential element to humans, and is considered to be a toxic metal ion. Since Al pans are the most commonly used cooking utensils in rural places an acoustic wave sensor was developed to quantify the amount of metal leaching when cooking some recipes. Sensitive layer of the sensor consists of a membrane with a specific ionophore

Marta I. S. Veríssimo; João A. B. P. Oliveira; M. Teresa S. R. Gomes

2006-01-01

209

Recent development in aluminium alloys for aerospace applications  

Microsoft Academic Search

Driven by the increasing requirements from aircraft producers, Hoogovens Aluminium Rolled Products GmbH, together with Hoogovens Research & Development, has enhanced the property combinations of their aircraft materials. For these types of material, optimised processing routes as well as new alloy chemistries have been investigated. Whilst retaining the strength levels required by the aerospace industry, new processing routes offer major

A Heinz; A Haszler; C Keidel; S Moldenhauer; R Benedictus; W. S Miller

2000-01-01

210

Local potential measurements with the SKPFM on aluminium alloys  

Microsoft Academic Search

Nowadays several measuring techniques, like SVET, SRET and Kelvin probe, exist to study local potential differences on alloys surfaces. One very sensitive technique with good spatial resolution is scanning Kelvin probe force microscopy. This technique enables direct measurement of the local Volta potential differences resulting from very complicated microstructures due to the thermal history of the produced aluminium alloys. In

J. H. W de Wit

2004-01-01

211

Properties and deformation behaviour of severe plastic deformed aluminium alloys  

Microsoft Academic Search

Two and three dimensional FEM analysis of different aluminium alloys by equal channel angular pressing using Abaqus code show lower equivalent plastic strain on outer side of both transverse and longitudinal sections of workpiece. HV hardness and microhardness tests on different ecapped alloys show that the outer sides of processed alloys also are characterized by lower values.Microstructure analysis of different

P. Leo; E. Cerri; P. P. De Marco; H. J. Roven

2007-01-01

212

Fatigue behaviour of GMAW welded aluminium alloy AA7020  

Microsoft Academic Search

The aim of this investigation is to evaluate the influence on fatigue behaviour of the finishing of the bulge in a welded aluminium–zinc–magnesium alloy AA7020. It was determined that total or partial elimination of the bulge has very little influence on its behaviour, giving a very similar result on both cases, where one is better than the other by only

C. A. Bloem; M. D. Salvador; V. Amigó; A. Vicente

2009-01-01

213

Internal friction in hydrogen-charged aluminium alloys  

Microsoft Academic Search

Measurements of the internal friction of aluminium alloys containing hydrogen have been made from 77 to 300 K at 35 kHz using a composite resonator technique. Perfection of a metallic bonding technique for the transducer-specimen composite produced background dampings which were typically of the order Q ? 10. Criteria which relied on measurements at harmonic frequencies were used to distinguish

M. Leger; G. R. Piercy

1981-01-01

214

Cavitation-aided grain refinement in aluminium alloys  

Microsoft Academic Search

This thesis deals with grain refinement under the influence of ultrasonic-driven cavitation in aluminium casting processes. Three major goals of this research were: (1) to identify the mechanism of the cavitation-aided grain refinement at different stages of solidification; (2) to reveal the conditions of the stable grain refinement effect in different alloying systems; and (3) to apply the knowledge gained

T. V. Atamanenko

2010-01-01

215

Selective Recovery Of Aluminium And Silver From Electroplating Wastes  

Microsoft Academic Search

In this study, sludge from an electroplating wastewater treatment facility was treated with acids to extract heavy and precious metals. Metals of interest in the study were Aluminium and Silver, which were relatively high in concentration in the sludge sample. Acids used in the study were Hydrochloric and Nitric acid. Experiments were conducted at various temperatures and acid concentrations. It

Vasanthi Sethu; M. K. Aroua

216

Recent development in aluminium alloys for the automotive industry  

Microsoft Academic Search

The growing demand for more fuel-efficient vehicles to reduce energy consumption and air pollution is a challenge for the automotive industry. The characteristic properties of aluminium, high strength stiffness to weight ratio, good formability, good corrosion resistance, and recycling potential make it the ideal candidate to replace heavier materials (steel or copper) in the car to respond to the weight

W. S. Miller; L. Zhuang; J. Bottema; A. J. Wittebrood; P De Smet; A. Haszler; A. Vieregge

2000-01-01

217

A rapid hydroponic screening for aluminium tolerance in barley  

Microsoft Academic Search

Selection and breeding of crops for aluminium (Al) tolerance is a useful approach to increase production on acid soils. This requires a rapid and reliable system to discriminate between Al-tolerant and Al-sensitive genotypes. A hydroponic system was developed to screen for Al tolerance in barley (t Hordeum vulgare L.) to overcome several problems encountered in previous screening methods. Four levels

Jian Feng Ma; Shao Jian Zheng; Xiao Feng Li; Kazuyoshi Takeda; Hideaki Matsumoto

1997-01-01

218

Aluminium cycling in the soil-plant-animal-human continuum  

Microsoft Academic Search

A critical review of the literature on Al toxicity in plants, animals and humans reveals a similar mode of Al action in all living organisms, namely interference with the secondary messenger system (phosphoinositide and cytosolic Ca2+ signalling pathways) and enhanced production of reactive oxygen species resulting in oxidative stress. Aluminium uptake by plants is relatively quick (across the intact plasma

Z. Rengel

2004-01-01

219

Excimer laser induced surface nitriding of aluminium alloy  

Microsoft Academic Search

This study describes a technique for the growth of thin nitride layer on aluminium alloy samples by direct laser synthesis with the advantages of good adhesion and localisation. The laser irradiation process is performed using an XeCl excimer laser (?=308 nm, 50 Hz) under a nitrogen atmosphere. The laser induced plasma interacts with the melted sample surface resulting in nitrogen

E. Sicard; C Boulmer-Leborgne; T Sauvage

1998-01-01

220

Galvanic corrosion of laser weldments of AA6061 aluminium alloy  

Microsoft Academic Search

Galvanic corrosion of laser welded AA6061 aluminium alloy, arising from the varying rest potentials of the various weldment regions, was examined. The weld fusion zone is found to be the most cathodic region of the weldment while the base material is the most anodic region. The rate of galvanic corrosion, controlled by the cathodic process at the weld fusion zone,

A. B. M. Mujibur Rahman; S. Kumar; A. R. Gerson

2007-01-01

221

Titanium aluminide formation in Ti implanted aluminium alloy  

Microsoft Academic Search

Ion implantation has been extensively used for modifying the surfaces of engineering materials. In the present report, the implantation of type 6061 aluminium alloy with Ti ions has been investigated as a function of dose and substrate temperature. Retained doses in the range 0.8?6 × 1017 ions cm?2 were studied in order to examine the effect of Ti concentration on

S. T. Knight; P. J. Evans; M. Samandi

1996-01-01

222

Titanium aluminide formation in Ti implanted aluminium alloy  

Microsoft Academic Search

Ion implantation has been extensively used for modifying the surfaces of engineering materials. In the present report, the implantation of type 6061 aluminium alloy with Ti ions has been investigated as a function of dose and substrate temperature. Retained doses in the range 0.8-6 × 1017 ions cm-2 were studied in order to examine the effect of Ti concentration on

P. J. Evans; S. T. Knight; M. Samandi

1996-01-01

223

Aqueous tape casting of reaction bonded aluminium oxide (RBAO)  

Microsoft Academic Search

Reaction bonding of alumina (RBAO) has been proved to be a successful route to make high-performance alumina. However, the aluminium metal in the starting mixtures prevents using aqueous processing techniques in the initial phase. Here a route is presented for aqueous tape casting of RBAO by hydrophobization of the starting powder and preparing a suitable tape cast suspension. Thermal analysis

M. D. Snel; FMM Snijkers; JJ Luyten; AA Kodentsov

2007-01-01

224

Experimental study of friction in aluminium bolted joints  

Microsoft Academic Search

This study aims at developing an experimental tool useful to define accurately the friction coefficients in bolted joints and, therefore, at relating precisely the tightening torque to the bolt preloading force in some special components used in front motorbike suspensions. The components under investigation are some clamped joints made of aluminium alloy. The preloading force is achieved by applying a

D. Croccolo; M. de Agostinis; N. Vincenzi

2010-01-01

225

High strain rate testing of aluminium alloy & high speed photography  

Microsoft Academic Search

In order to gain in safety, it is necessary to study material responses in severe conditions, for instance under dynamic loadings, especially in the case of light alloys used in car, nautical and aeronautical industries. The initiated study concerns fatigue-impact coupling effects on a commercial aluminium alloy (AA5454) used in car industry. Through a part of this investigation, by modificating

M. Lambert; C. Froustey; J. L. Charles; J. L. Lataillade

2003-01-01

226

Heat generation during pulse operation of prototype aluminium electrolytic capacitors  

Microsoft Academic Search

Measurements were made of heat generation in aluminium electrolytic capacitor ‘sandwiches’ operating under pulse charge and discharge. With commercial anode foils the fraction of input power dissipated as heat in the dielectric is proportional to theDF of the oxide dielectric. There is also a dependence on the applied voltage that is thought to be due to frictional losses arising from

R. S. Alwitt; S. G. Parler

1995-01-01

227

Creep deformation characteristics of discontinuously reinforced aluminium-matrix composites  

Microsoft Academic Search

Recent developments in the study of creep behaviour of discontinuously reinforced aluminium-matrix composites (DRAMCs) at elevated temperatures are reviewed in this paper. These include the shapes of the creep curves, the origin and characteristics of the threshold stress, the creep strengthening of the DRAMCs, the nature of the rate-controlling processes, the effect of cyclic stress, and creep rupture. The DRAMCs

Z. Y. Ma; S. C. Tjong

2001-01-01

228

Carbon capture and the aluminium industry: preliminary studies  

Microsoft Academic Search

Carbonation of raw red mud produced by aluminium refineries and a chemically and physically neutralized red mud (Bauxsol™) has been carried out to study the capacity of these wastes to capture carbon dioxide. After only 5 min of carbonation of raw red mud, total alkalinity dropped 85%. Hydroxide alkalinity was almost totally consumed, carbonate alkalinity dropped by 88%, and bicarbonate

Graham B Jones; Gargi Joshi; Malcolm D Clark; David M McConchie

2006-01-01

229

Towards an understanding of the adjuvant action of aluminium  

Microsoft Academic Search

The efficacy of vaccines depends on the presence of an adjuvant in conjunction with the antigen. Of these adjuvants, the ones that contain aluminium, which were first discovered empirically in 1926, are currently the most widely used. However, a detailed understanding of their mechanism of action has only started to be revealed. In this Timeline article, we briefly describe the

Amy S. McKee; Michael W. Munks; Philippa Marrack

2009-01-01

230

Recovery of scandium from magnesium, aluminium and iron scrap  

Microsoft Academic Search

A hydrometallurgical route for recovering of scandium from magnesium, aluminium and iron dross or scrap was developed and the extraction isotherm for scandium with HDEHP established. After a single stage of leaching, extraction and stripping, nearly 100% recovery of scandium as scandium oxide resulted, while the separation of magnesium from scandium was also nearly 100%. About 10% of the iron

A. Ditze; K. Kongolo

1997-01-01

231

Design optimisation of aluminium recycling processes using Taguchi technique  

Microsoft Academic Search

In this paper, a robust design method is developed for reducing cost and improving quality in aluminium recycling. An experimental investigation into the process parameter effects is presented to determine the optimum configuration of design parameters for performance, quality and cost. The Taguchi method is applied initially to plan a minimum number of experiments. Orthogonal array techniques are used to

A. R Khoei; I Masters; D. T Gethin

2002-01-01

232

Deformation behaviour of aluminium single crystals in ultraprecision diamond turning  

Microsoft Academic Search

The physical properties of the machined layer of single crystal aluminium after diamond turning were assessed by X-ray diffraction (XRD) to demonstrate the nature and extent of the plastic deformation process that had occurred in the workpiece. In the range of depth of cut investigated, the microstrain was found to vary with the crystallography of the machined surface, whereas the

S. To; W. B. Lee

2001-01-01

233

Joining techniques for aluminium spaceframes used in automobiles  

Microsoft Academic Search

Concerns regarding the environmental impact of motor vehicles are driving automotive manufactures to develop lighter, more fuel-efficient vehicles. Such a task is further compounded by customer demands for greater performance and more luxury and safety features, all of which tend to increase vehicle weight. Aluminium spaceframe body structures substantially reduce weight relative to traditional steel monocoques, whilst maintaining essential strength

T. A Barnes; I. R Pashby

2000-01-01

234

Analysis of cold gas dynamically sprayed aluminium deposits  

Microsoft Academic Search

Cold spray is a high rate, direct material deposition process that utilises the kinetic energy of particles sprayed at velocities in excess of 700 m s?1 to effect bonding through plastic deformation on impact. This paper describes the preliminary analysis of aluminium coatings deposited by this route. Attention is paid to splat morphology and instances of metallurgic bonding within the

R. Morgan; P. Fox; J. Pattison; C. Sutcliffe; W. O'Neill

2004-01-01

235

Roles of Organic Acid Anion Secretion in Aluminium Tolerance of Higher Plants  

PubMed Central

Approximately 30% of the world's total land area and over 50% of the world's potential arable lands are acidic. Furthermore, the acidity of the soils is gradually increasing as a result of the environmental problems including some farming practices and acid rain. At mildly acidic or neutral soils, aluminium(Al) occurs primarily as insoluble deposits and is essentially biologically inactive. However, in many acidic soils throughout the tropics and subtropics, Al toxicity is a major factor limiting crop productivity. The Al-induced secretion of organic acid (OA) anions, mainly citrate, oxalate, and malate, from roots is the best documented mechanism of Al tolerance in higher plants. Increasing evidence shows that the Al-induced secretion of OA anions may be related to the following several factors, including (a) anion channels or transporters, (b) internal concentrations of OA anions in plant tissues, (d) temperature, (e) root plasma membrane (PM) H+-ATPase, (f) magnesium (Mg), and (e) phosphorus (P). Genetically modified plants and cells with higher Al tolerance by overexpressing genes for the secretion and the biosynthesis of OA anions have been obtained. In addition, some aspects needed to be further studied are also discussed.

Yang, Lin-Tong; Qi, Yi-Ping; Jiang, Huan-Xin; Chen, Li-Song

2013-01-01

236

Entwicklung solarselektiver Absorberschichten auf Aluminium fuer Solarkollektoren. Abschlussbericht. (Development of solar selective absorber layers on aluminium. Final report).  

National Technical Information Service (NTIS)

A new electrolytic process was developed to form solar selective layers on aluminium. In the developed process, both the formation of the alumina layer and the deposition of metals into the layer takes place in only one treatment step using a single elect...

D. Hoenicke T. Moeller T. Schwarz

1998-01-01

237

STUDIES OF THE CORROSION OF ALUMINIUM AND ITS ALLOYS FOR NUCLEAR REACTOR. I. CORROSION BEHAVIOR OF ALUMINIUM IN HIGH PURITY WATER UP TO THE TEMPERATURE OF 100 C  

Microsoft Academic Search

Studies were made of the corrosion characteristics of aluminium in high-; purity water up to the temperature of 100 nif- C, and included studies ; of corrosion products, the effect of dissolved oxygen on corrosion, and the use ; of inhibitors to suppress corrosion. The corrosion product film on aluminium in ; high-purity water at the temperature of up to

G. Ito; Y. Shimizu; F. Sawayanagi

1962-01-01

238

Fluxless laser brazing of aluminium alloy to galvanized steel using a tandem beam – dissimilar laser brazing of aluminium alloy and steels  

Microsoft Academic Search

Tandem beam brazing with aluminium filler metal (BA4047) was conducted in order to develop the fluxless laser brazing technique of aluminium alloy (AA6022) to galvanized steels (GA and GI steels). Laser powers of tandem beam and offset distance of preheating beam from the root to the steel base metal were varied. Sound braze beads could be obtained by optimizing the

Kazuyoshi Saida; Haruki Ohnishi; Kazutoshi Nishimoto

2010-01-01

239

Experimental model of the interfacial instability in aluminium reduction cells  

NASA Astrophysics Data System (ADS)

A solution has been found to the long-standing problem of experimental modelling of the interfacial instability in aluminium reduction cells. The idea is to replace the electrolyte overlaying molten aluminium with a mesh of thin rods supplying current down directly into the liquid metal layer. This eliminates electrolysis altogether and all the problems associated with it, such as high temperature, chemical aggressiveness of media, products of electrolysis, the necessity for electrolyte renewal, high power demands, etc. The result is a room temperature, versatile laboratory model which simulates Sele-type, rolling pad interfacial instability. Our new, safe laboratory model enables detailed experimental investigations to test the existing theoretical models for the first time.

Pedchenko, A.; Molokov, S.; Priede, J.; Lukyanov, A.; Thomas, P. J.

2009-10-01

240

Results of the Experiment: Welding of Aluminium Alloy in Microgravity  

NASA Astrophysics Data System (ADS)

An experiment on "dendritic growth in aluminium alloy welding" was performed by the UNIBO team during the 3rd Student Parabolic Flight Campaign and the 30th Professional Parabolic Flight Campaign organised by ESA. Its purpose was to achieve a better understanding of crystal growth during tungsten inert gas (TIG) welding of an aluminium alloy to define the main parameters affecting the process under microgravity condition. The experiment had 4 phases : The paper discusses different aspects of the research, paying particularly attention not only to the influence of gravity, but also to other factors influencing welding microstructure, such as the Marangoni effect and the thermal transfer from the electrode to the material. The paper conclude the dissertation of the results offering new perspectives for welding studies and proposing a new approach to the scientific community to investigate this materials processes for manufacturing.

Ferretti, S.; Amadori, K.; Boccalatte, A.; Alessandrini, M.; Freddi, A.; Persiani, F.; Poli, G.

2002-01-01

241

Aluminium Distribution in HDEHP-Diluent-Citric Acid-DTPA Extraction System and Its Effect on Transplutonium and Rare Earth Elements Separation.  

National Technical Information Service (NTIS)

Aluminium extraction with HDEHP solutions in decane, containing isooctanol, from aqueous solutions of citric acid and DTPA is studied along with aluminium effect on curium, californium and europium extraction. It is shown that aluminium extraction with HD...

S. N. Kovantseva V. M. Nikolaev V. A. Kasimova V. T. Filimonov

1982-01-01

242

Discharge characterization in plasma electrolytic oxidation of aluminium  

Microsoft Academic Search

Digital video imaging of the plasma electrolytic oxidation (PEO) of aluminium has been performed, which allowed evaluation of both dimensional characteristics of individual microdischarges appearing at the oxide-electrolyte interface and their collective behaviour throughout the oxidation process. It has been shown that the microdischarge cross-sectional dimensions vary within the range 0.01-1.35 mm2. In the course of PEO processing, small localized

A. L. Yerokhin; L. O. Snizhko; N. L. Gurevina; A. Leyland; A. Pilkington; A. Matthews

2003-01-01

243

Plasma electrolytic oxidation of pre-anodized aluminium  

Microsoft Academic Search

The influence of an anodizing pre-treatment in sulphuric acid is investigated on plasma electrolytic oxidation (PEO) of aluminium in silicate electrolyte under constant rms current. The presence of the anodic film is shown to promote the establishment of a micro-arc regime that is favourable for growth of the PEO coating. The incorporation of the pre-formed film into the coating appears

E. Matykina; R. Arrabal; A. Mohamed; P. Skeldon; G. E. Thompson

2009-01-01

244

Mechanical Properties of Particulate Reinforced Aluminium Alloy Matrix Composite  

Microsoft Academic Search

This paper discusses the mechanical properties of Titanium Carbide (TiC) particulate reinforced aluminium-silicon alloy matrix composite. TiC particulate reinforced LM6 alloy matrix composites were fabricated by carbon dioxide sand molding process with different particulate weight fraction. Tensile strength, hardness and microstructure studies were conducted to determine the maximum load, tensile strength, modulus of elasticity and fracture surface analysis have been

M. Sayuti; S. Sulaiman; B. T. H. T. Baharudin; M. K. A. Arifin; S. Suraya; T. R. Vijayaram

2011-01-01

245

Aluminium-induced morphogenic and biochemical variations of Bacopa Monniera  

Microsoft Academic Search

Shoots and roots ofBacopa monniera (L.) Wettst. have been regenerated from nodal segments on MS medium containing combinations of NAA and BAP. The cultures\\u000a showed 100% regeneration on MS (sucrose 2%) medium added with NAA (0.2 mg L-1), BAP (0.5 mg L-1) and glutamine (50 mg L-1). Supplemented with aluminium chloride (up to 400 ?M), this medium could ensure successful

G. Ali; P. S. Srivastava; M. Iqbal

1998-01-01

246

Interfacing the aluminium-air battery with telecommunications equipment  

Microsoft Academic Search

The tests carried out by British Telecom (BT) on the aluminum-air battery with regard to using the battery in a standby power system are described. The background to BT's interest in the aluminium-air battery is outlined along with the design considerations of a prototype power system to be installed in the switching network. The need for an interfacing DC\\/DC converter

P. Hodgson; M. Heath

1990-01-01

247

Differential toxicity of novel aluminium compounds in hippocampal culture  

Microsoft Academic Search

The dependence of aluminium (Al) toxicity on its chemical form has been implicated in previous studies, but the complex chemistry of Al in solutions of biological preparations has hampered a reliable assessment. Here, we assessed the toxicity of select and pure Al(III) citrate compounds, well-characterized at physiological pH, and compared it with Al from standard solution (in HCl). Cell death

Bettina Platt; Alison J. Drysdale; Christiane Nday; Eva v. Linstow Roloff; Benjamin D. Drever; Athanasios Salifoglou

2007-01-01

248

A numerical study of MSD in aluminium alloys  

Microsoft Academic Search

This paper uses the finite element alternating technique to study the effect of multiple cracks, i.e. multi-site damage (MSD), in an aluminium alloy plate. This problem arose as a result of MSD seen in the aft bulkhead of F\\/A-18 aircraft in service with the Royal Australian Air force (RAAF). For the particular problem under investigation, it is shown that the

R. Jones; S. Hammond; J. F. Williams; M. Heller

1995-01-01

249

Fracture and Fatigue Behaviour of Aluminium Matrix Composite Automotive Pistons  

Microsoft Academic Search

The fracture and fatigue behaviour of prototype automotive pistons produced in an aluminium alloy matrix composite in industrial\\u000a conditions has been studied. Fracture toughness increased when the testing temperature rose from 20° to 75°C and kept near\\u000a constant up to 250°C, when a significantly lower value was recorded. A change in the failure operating mechanism, which can\\u000a explain this trend,

Ane M. García-Romero; Pedro Egizabal; Angel M. Irisarri

2010-01-01

250

PID self-tuning controller for aluminium rolling mill  

Microsoft Academic Search

An implementation of a self-tuning proportional-integral-derivative (PID) controller on a single-stand cold-rolling aluminium mill is described. The approach compensates for changes in the process and product without requiring a priori knowledge of these changes. The design is based on an adaptive control scheme in which the control coefficients are adjusted according to estimates of the plant parameters and a preselected

R. E. Brown; G. N. Maliotis; J. A. Gibby

1990-01-01

251

Design of CNG tank made of aluminium and reinforced plastic  

Microsoft Academic Search

A compressed natural gas storage tank suitable for gas operated vehicles can be made of thin-walled aluminium liners with a glass\\/epoxy reinforcement overwind. The hybrid construction allows the higher tensile strength of the glass reinforcement to be utilized, whilst giving a structure which weeps before burst and self-health. The advantages of the chosen construction can only be maximized for the

L. Varga; A. Nagy; A. Kova´cs

1995-01-01

252

Outcome of erbium:yttrium aluminium garnet laser resurfacing treatments  

Microsoft Academic Search

Erbium:yttrium aluminium garnet (erbium:YAG) laser treatment was used to resurface skin abnormalities in patients suffering\\u000a from conditions that included epidermal naevi, tuberous sclerosis, angiofibromata, neurofibromatosis, and scarring caused\\u000a by acne or other means. Patients completed self-report questionnaires before their first laser test patch session, and again\\u000a approximately 4 months after one treatment, so that its success could be evaluated from the

R. P. Cole; D. Widdowson; J. C. Moore

2008-01-01

253

Evaluation of ultrasonic aluminium degassing by piezoelectric sensor  

Microsoft Academic Search

The purpose of this work was the development of a reliable technique to evaluate the intensity of acoustic cavitation during degassing of aluminium melts and to use it to select the optimum processing time for an envisaged degassing efficiency.A high sensitivity piezoelectric disk type device was used as a sensing feedback in water and liquid AlSi9Cu3 alloy. The signal acquisition

H. Puga; J. Barbosa; J. Gabriel; E. Seabra; S. Ribeiro; M. Prokic

2011-01-01

254

Melatonin reduces oxidative damage induced by aluminium in rat kidney  

Microsoft Academic Search

We evaluated the effect of melatonin (Mel), in male Wistar rats which received aluminium (Al) lactate for 12 weeks (0.57mg Al\\/100g body weight (b.w.), i.p. three times per week). Moreover rats received Mel (10mg\\/kg b.w. i.p. 5 days\\/weeks) for 12 weeks. At the end of the treatment water and sodium balances were studied, and nephrogenic cyclic adenosine monophosphate (cAMP) was

Stella Mahieu; María del Carmen Contini; Marcela González; Néstor Millen

2009-01-01

255

Cracking of AFNOR 7020 aluminium alloy component: A metallurgical investigation  

Microsoft Academic Search

Aluminium alloy of Al–4.5Zn–1.5Mg system, belonging to age hardenable, high strength category is being used for the fabrication of various components. The Al alloy component was part of a conduit line for filling the liquid chemical to its storage tank. The component consisted of an extruded tube, TIG welded to a bulb, which was fabricated from Al alloy forgings. A

Abhay K. Jha; V. Diwakar; K. Sreekumar; M. C. Mittal

2006-01-01

256

Neurotoxic effects of aluminium on embryonic chick brain cultures  

Microsoft Academic Search

Toxic damage of brain cells by aluminium (A1) is discussed as a possible factor in the development of neurodegenerative disorders in humans. To investigate neurotoxic effects of A1, serum-free cultures of mechanically dissociated embryonic chick (stage 28–29) forebrain, brain stem and optic tectum, and for comparison meningeal cells, were treated with A1 (0–1000 M) for 7 days. Effects of A1

Judith Pia Miiller; Arend Bruinink

1994-01-01

257

Aluminium sputter deposition onto polyimide-coated substrates  

Microsoft Academic Search

An aluminium deposition process onto PIQ (polyimide isoindroqui hazoline-dione: Hitachi Chemical)-coated substrates was developed for a continuous cassette-to-cassette sputtering machine. The baking process of the substrates in vacuum was studied for various film thicknesses and heating rates. PIQ releases water vapor upon heating in a vacuum and gives a maximum release rate at around 120°C with a heating rate of

Shigeru KOBAYASHI; Akira OKAMOTO; Yasunori NARIZUKA; Toshiyuki ARAI; Akihiro KENMOTSU; Minoru TANAKA; Yoshinao KAWASAKI

1990-01-01

258

Tubular hydroforming of automotive side members with extruded aluminium profiles  

Microsoft Academic Search

Side member left and side member right, which go from bumper to bumper in a car body, were at the focus in the present study. These side members were produced using straight round (hollow with a circular cross-section) extruded aluminium profiles as tube material. The tubes were bent and hydroformed. Rotary-draw bending yielded the best result. A spread within 8mm

Nader Asnafi; Tomas Nilsson; Gunnar Lassl

2003-01-01

259

Tube bending and hydroforming of aluminium alloy S-rails  

Microsoft Academic Search

This research examines the effect of the tube bending and hydroforming processes on the characteristics of aluminium alloy\\u000a s-rail structures used in crash applications. Tube bending and hydroforming experiments are conducted using a fully instrumented\\u000a mandrel-rotary draw tube bender and a 1,000 tonne hydroforming press to investigate the effect of bend severity on the thickness\\u000a and strain distributions within the

D. A. Oliveira; M. J. Worswick

2009-01-01

260

Aluminium and lead: molecular mechanisms of brain toxicity  

Microsoft Academic Search

The fact that aluminium (Al) and lead (Pb) are both toxic metals to living organisms, including human beings, was discovered\\u000a a long time ago. Even when Al and Pb can reach and accumulate in almost every organ in the human body, the central nervous\\u000a system is a particular target of the deleterious effects of both metals. Select human population can

Sandra V. Verstraeten; Lucila Aimo; Patricia I. Oteiza

2008-01-01

261

Pretreatment of AA6060 aluminium alloy for adhesive bonding  

Microsoft Academic Search

AA6060-T6 aluminium extrusions have been subjected to various surface treatments before bonding with an epoxy based adhesive and subsequent exposure to chloride and humid atmosphere (82% RH, 40°C) for 50 days. Single lap joints given an alkaline etch pre-treatment before bonding suffered a 7% reduction in strength as a result of environmental exposure. Desmutting in nitric acid after a similar

O. Lunder; B. Olsen; K. Nisancioglu

2002-01-01

262

Low velocity perforation of AA5083-H116 aluminium plates  

Microsoft Academic Search

This paper presents an experimental and numerical investigation on low velocity perforation (in the velocity range 3.5–15.8m\\/s) of AA5083-H116 aluminium plates. In the tests, square plates were mounted in a circular frame and penetrated by a cylindrical blunt-nosed projectile. The perforation process was then computer analysed using the nonlinear finite element code LS-DYNA in order to investigate the effects of

F. Grytten; T. Børvik; O. S. Hopperstad; M. Langseth

2009-01-01

263

Synthesis and physicochemical properties of cobalt aluminium hydrotalcites  

Microsoft Academic Search

Cobalt aluminium hydrotalcites with different compositions were prepared by a coprecipitation method under low supersaturation conditions. The compounds were characterized by X-ray diffraction (XRD), infrared absorption (IR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and BET surface area measurements. XRD and IR studies revealed that all the compounds are single-phase crystallized under a hydrotalcite-like network. Hydrothermal treatments given to the

S. Kannan; S. Velu; V. Ramkumar; C. S. Swamy

1995-01-01

264

Barley mutants with increased tolerance to aluminium toxicity  

Microsoft Academic Search

Acid soil and associated aluminium toxicity are considered as the number one abiotic factor limiting crop production. Over\\u000a 2 billion hectares of acid soils exist world-wide, both in tropical and moderate climatic zones. In Poland acid soils represent\\u000a up to60% of arable land. At soil pH < 5.0 Al ions become soluble in water and toxic to plants. Genetic improvement

M. Nawrot; I. Szarejko; M. Maluszynski

2001-01-01

265

Effect of CH 4 Ion Implantation in Pure Aluminium  

Microsoft Academic Search

In this paper, aluminium samples with 99.96% purity were exposed to ion beam, extracted from CH4 plasma. Implantation of ions were performed for 50 keV energy and various doses ranging from 1 × 1017 to 6 × 1017 ions\\/cm2. Morphology of surfaces, roughness and its evolution during variation of ion dose has been studied by atomic force microscopy\\u000a (AFM). Microstructure of the modified surfaces after

A. H. SariA; A. R. Jabbari; M. Ghoranneviss

2011-01-01

266

Design of a dome-shaped aluminium water battery  

Microsoft Academic Search

Aluminium\\/water batteries using hydrogen evolving cathodes are one of the candidate batteries for sub-sea application. However, it is impractical to use parallel plate construction because the significant increase in the anode-cathode gap during long term anodic discharge leads to unacceptable iR losses. A conceptual design, using a dome-shaped configuration, is presented and preliminary tests on a prototype show that such

P. K. Shen; A. C. C. Tseung; C. Kuo

1994-01-01

267

Self-pierce riveting of three high strength steel and aluminium alloy sheets  

Microsoft Academic Search

The joinability of the self-pierce riveting process of three high strength steel and aluminium alloy sheets was investigated.\\u000a The effects of the sheet strength and sheet combination on the deforming behaviour were examined under the fixture of the\\u000a lower aluminium alloy sheet. Although the joining of three aluminium alloy and mild steel sheets is comparatively easy due\\u000a to small difference

Y. Abe; T. Kato; K. Mori

2008-01-01

268

Potentiometric determination of the ‘formal’ hydrolysis ratio of aluminium species in aqueous solutions  

Microsoft Academic Search

The ‘formal’ hydrolysis ratio (h=C(OH?)added\\/C(Al)total) of hydrolysed aluminium-ions is an important parameter required for the exhaustive and quantitative speciation–fractionation of aluminium in aqueous solutions. This paper describes a potentiometric method for determination of the formal hydrolysis ratio based on an automated alkaline titration procedure. The method uses the point of precipitation of aluminium hydroxide as a reference (h=3.0) in order

Agathe C. Fournier; Kirill L. Shafran; Carole C. Perry

2008-01-01

269

Fundamental and applied aspects of the plasma-assisted nitriding process for aluminium and its alloys  

Microsoft Academic Search

The insufficient wear resistance of aluminium and its alloys is a well-known problem. Different surface treatment methods have been developed to increase the resistance. Compared to the electrochemical processes, the plasma-assisted nitriding of aluminium is a new method without ecological problems. In this paper different possibilities of plasma-activated nitriding are introduced. Due to the low electrical conductivity of the aluminium

H. R. Stock; C. Jarms; F. Seidel; J. E. Döring

1997-01-01

270

Mechanical and tribological properties of zinc-aluminium metal-matrix composites  

Microsoft Academic Search

Recently, commercial Zn-Al foundry alloys such as ZA-27 have found increasing use for many applications and have competed effectively against copper, aluminium and iron-based foundry alloys. However, the elevated temperature (> 100°C) properties of zinc-aluminium alloys are unsatisfactory and restrict their use in some applications. One viable approach to improving the elevated temperature properties is to reinforce the zinc-aluminium alloys

S. H. J. Lo; S. Dionne; M. Sahoo; H. M. Hawthorne

1992-01-01

271

Use of vermicompost extract as an aluminium inhibitor in aqueous solutions  

Microsoft Academic Search

Vermicompost extract (VCE) demonstrated the ability to raise the measured pH level of an acid soil thus showing a potential to limit aluminium toxicity. The relatively high proportion of humic substances (60% of VCE solid matter) suggested the possibility of formation of stable chelates with aluminium ions. A rate?based colorimetric method was utilised measuring at 585 nm the aluminium?pyrocatechol violet

D. Alter; A. Mitchell

1992-01-01

272

Capacitance and photoelectrochemical studies for the assessment of anodic oxide films on aluminium  

Microsoft Academic Search

Photoelectrochemical spectroscopy and capacitance measurements were used in this work to assess the electronic properties of the oxide films formed on 99.5% aluminium and 2024-T3 aluminium alloy by anodising in a sulphuric-boric bath. The morphology of these films was also studied by transmission electron microscopy cross-section observations.The results obtained indicate that the oxide films formed on aluminium show a n-type

J. C. S. Fernandes; R. Picciochi; M. Da Cunha Belo; T. Moura e Silva; M. G. S. Ferreira; I. T. E. Fonseca

2004-01-01

273

Effect of oxide particles on the stabilization and final microstructure in aluminium.  

PubMed

Bulk aluminium samples containing alumina particles have been produced by different severe plastic deformation methods. Aluminium foils with different initial foil thicknesses were cold rolled to different amounts of strain and aluminium powders were consolidated and deformed by high pressure torsion (HPT). During processing, alumina particles from the foil or particle surface are easily incorporated and dispersed in the bulk material. The influence of these alumina particles on the developing microstructures and the mechanical properties has been studied. PMID:21976787

Bachmaier, Andrea; Pippan, Reinhard

2011-09-25

274

Formation mechanism of an aluminium-based chemical conversion coating on AZ91D magnesium alloy  

Microsoft Academic Search

An environmentally clean aluminium-based conversion coating on AZ91D magnesium alloy was studied in aluminium nitrate solutions.\\u000a The morphology, composition, structure, and formation mechanism of the coating were investigated in detail using scanning\\u000a electron microscopy\\/energy dispersion spectrometry, X-ray diffraction, transmission electron microscopy, and electrochemical\\u000a corrosion tests. The results show that the conversion coating is composed of magnesium, aluminium, and oxygen, and

Wei-Ping Li; Xi-Mei Wang; Li-Qun Zhu; Wen Li

2010-01-01

275

Effect of oxide particles on the stabilization and final microstructure in aluminium  

PubMed Central

Bulk aluminium samples containing alumina particles have been produced by different severe plastic deformation methods. Aluminium foils with different initial foil thicknesses were cold rolled to different amounts of strain and aluminium powders were consolidated and deformed by high pressure torsion (HPT). During processing, alumina particles from the foil or particle surface are easily incorporated and dispersed in the bulk material. The influence of these alumina particles on the developing microstructures and the mechanical properties has been studied.

Bachmaier, Andrea; Pippan, Reinhard

2011-01-01

276

The influences of gypsum water-proofing additive on gypsum crystal growth  

Microsoft Academic Search

The gypsum water-proofing additives were composed of organic emulsion that were emulsified by polyvinyl alcohol and stearic acid and saline water-proofing additive made of alunite, carboxylic acid sodium, aluminium sulfate, etc. Using modern testing instrument, such as SEM, EPS, the influences of gypsum water-proofing additives on the crystal growth of gypsum products and its water-proof mechanism were analyzed from the

Jianquan Li; Guozhong Li; Yanzhen Yu

2007-01-01

277

Recovering obliterated engraved marks on aluminium surfaces by etching technique.  

PubMed

A study has been made of the characteristics of restoration of obliterated engraved marks on aluminium surfaces by etching technique. By etching different reagents on 0.61mm thick sheets of aluminium (99wt%) on which some engraved marks had been erased to different depths it was found that the reagent 60% hydrochloric acid and 40% sodium hydroxide on alternate swabbing on the surfaces was found to be the most sensitive one for these metal surfaces. This reagent was able to restore marks in the above plates erased down to 0.04mm below the bottom of the engraving. The marks also presented excellent contrast with the background. This reagent was further experimented with similar aluminium surfaces, but of relatively greater thickness of 1.5mm. It was noticed that the recovery depth increased slightly to 0.06mm; this suggested the dependence of recovery depth on the thickness of the sheet metal. Further, the depth of restoration decreased in cases where the original number was erased and over which a new number was engraved; the latter results are similar to those of steel surfaces reported earlier [M.A.M. Zaili, R. Kuppuswamy, H. Harun, Restoration of engraved marks on steel surfaces by etching technique, Forensic Sci. Int. 171 (2007) 27-32]. PMID:18313246

Baharum, Mohd Izhar Mohd; Kuppuswamy, R; Rahman, Azari Abd

2008-03-04

278

Model of Non-premixed Combustion of Aluminium---Air Mixtures  

NASA Astrophysics Data System (ADS)

For solving the problem of shock-induced dissemination and burning of aluminium particles in air, we have developed a new solver based on equilibrium equation of states (EOS) of 2-phase reactive mixtures. The solver uses two pre-calculated tables; the larger one describes the equilibrium states of reaction products and the smaller one describes states of fresh air. Being linked with gas-dynamics equations, the solver finds iteratively the mixture pressure and temperature; in addition it furnishes a complete description of chemical and physical transformations. 2D numerical simulations give encouraging agreement with experimental pressure histories recorded on the chamber wall. It is shown that multiple blast wave reflections from the walls of the chamber strongly accelerate particle burning. The results demonstrate the advantages of the equilibrium EOS model and appeal for 3D AMR calculations on massively-parallel computers, which should better define the initial stage of turbulent particle dissemination.

Khasainov, Boris; Kuhl, Allen; Victorov, Sergey; Neuwald, Peter

2005-07-01

279

An improved ocean model of aluminium: the effects of circulation, sediment resuspension and biological incorporation  

NASA Astrophysics Data System (ADS)

The distribution of dissolved aluminium (Al) in the ocean is of interest because of its potential impact on diatom remineralisation and the use of surface ocean Al as a tracer for dust. Previously, the ocean Al concentration has been simulated reasonably well with only a dust source and scavenging as the removal process. In this study the simulation has been significantly improved by a more refined circulation and the addition of a sediment resuspension source. The latter confirms that the most significant sources of Al to the ocean are dust deposition and sediment resuspension. Simulations with biological incorporation have been performed as well. These show that this can be an important removal process. However, this study does not provide a definitive answer to the question what the relative amount of incorporation is compared to scavenging.

van Hulten, M. M. P.; Sterl, A.; Middag, R.; de Baar, H. J. W.; Gehlen, M.; Dutay, J.-C.; Tagliabue, A.

2013-09-01

280

Analysis of Machining Characteristics in Additive Mixed Electric Discharge Machining of Nickel Based Super Alloy Inconel 718  

Microsoft Academic Search

Additive mixed electric discharge machining (AEDM) is a novel innovation for enhancing the capabilities of electrical discharge machining process. The objective of present research work is to study the influence of operating process input parameters on machining characteristics of nickel based super alloy (Inconel 718) in aluminium additive mixed EDM of with copper electrode. The effectiveness of AEDM process on

Anil Kumar; Sachin Maheshwari; Chitra Sharma; Naveen Beri

2011-01-01

281

Aluminium localization in root tips of the aluminium-accumulating plant species buckwheat (Fagopyrum esculentum Moench).  

PubMed

Aluminium (Al) uptake and transport in the root tip of buckwheat is not yet completely understood. For localization of Al in root tips, fluorescent dyes and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) were compared. The staining of Al with morin is an appropriate means to study qualitatively the radial distribution along the root tip axis of Al which is complexed by oxalate and citrate in buckwheat roots. The results compare well with the distribution of total Al determined by LA-ICP-MS which could be reliably calibrated to compare with Al contents by conventional total Al determination using graphite furnace atomic absorption spectrometry. The Al localization in root cross-sections along the root tip showed that in buckwheat Al is highly mobile in the radial direction. The root apex predominantly accumulated Al in the cortex. The subapical root section showed a homogenous Al distribution across the whole section. In the following root section Al was located particularly in the pericycle and the xylem parenchyma cells. With further increasing distance from the root apex Al could be detected only in individual xylem vessels. The results support the view that the 10 mm apical root tip is the main site of Al uptake into the symplast of the cortex, while the subapical 10-20 mm zone is the main site of xylem loading through the pericycle and xylem parenchyma cells. Progress in the better molecular understanding of Al transport in buckwheat will depend on the consideration of the tissue specificity of Al transport and complexation. PMID:21831842

Klug, Benjamin; Specht, André; Horst, Walter J

2011-08-09

282

Do aluminium-based phosphate binders continue to have a role in contemporary nephrology practice?  

PubMed Central

Background Aluminium-containing phosphate binders have long been used for treatment of hyperphosphatemia in dialysis patients. Their safety became controversial in the early 1980's after reports of aluminium related neurological and bone disease began to appear. Available historical evidence however, suggests that neurological toxicity may have primarily been caused by excessive exposure to aluminium in dialysis fluid, rather than aluminium-containing oral phosphate binders. Limited evidence suggests that aluminium bone disease may also be on the decline in the era of aluminium removal from dialysis fluid, even with continued use of aluminium binders. Discussion The K/DOQI and KDIGO guidelines both suggest avoiding aluminium-containing binders. These guidelines will tend to promote the use of the newer, more expensive binders (lanthanum, sevelamer), which have limited evidence for benefit and, like aluminium, limited long-term safety data. Treating hyperphosphatemia in dialysis patients continues to represent a major challenge, and there is a large body of evidence linking serum phosphate concentrations with mortality. Most nephrologists agree that phosphate binders have the potential to meaningfully reduce mortality in dialysis patients. Aluminium is one of the cheapest, most effective and well tolerated of the class, however there are no prospective or randomised trials examining the efficacy and safety of aluminium as a binder. Aluminium continues to be used as a binder in Australia as well as some other countries, despite concern about the potential for toxicity. There are some data from selected case series that aluminium bone disease may be declining in the era of reduced aluminium content in dialysis fluid, due to rigorous water testing. Summary This paper seeks to revisit the contemporary evidence for the safety record of aluminium-containing binders in dialysis patients. It puts their use into the context of the newer, more expensive binders and increasing concerns about the risks of calcium binders, which continue to be widely used. The paper seeks to answer whether the continued use of aluminium is justifiable in the absence of prospective data establishing its safety, and we call for prospective trials to be conducted comparing the available binders both in terms of efficacy and safety.

2011-01-01

283

Effect of aluminium filtration on dose and image quality in paediatric slot-scanning radiography.  

PubMed

This paper examines the effect that a 1.8 mm aluminium filter has on paediatric patient dose and image quality for linear slot scanning radiography (LSSR). A dynamic dose prediction model for LSSR accurately predicted the dose reduction effects of added aluminium filtration. A cadaver imaging study was carried out to assess the effects of filtration on image quality. With 1.8 mm added aluminium filtration, no visible degradation to image contrast or clarity was found, and in some cases the aluminium filtration improved the image quality as judged by radiologists. PMID:24110192

Perks, Td; Trauernicht, C; Hartley, T; Hobson, C; Lawson, A; Scholtz, P; Dendere, R; Steiner, S; Douglas, Ts

2013-07-01

284

Influence of magnesium and aluminium ions on the copper a.c. deposition into aluminium anodic oxide film nanotubes  

Microsoft Academic Search

The influence of Mg2+ and Al3+ ions on a.c. deposition of copper nanowires into aluminium anodic oxide film (AOF) nanotubes has been studied using cyclic voltammetry and d.c. plasma emission spectrometry. From the analysis of copper quantities deposited into the Al AOF nanotubes (mCu), 0.02 M MgSO4 concentration was found to be optimal for Cu(II) solutions. Moreover, it was shown

A. Jagminas

2002-01-01

285

Spatial aluminium sensitivity of root apices of two common bean (Phaseolus vulgaris L.) genotypes with contrasting aluminium resistance  

Microsoft Academic Search

The initial response of plants to aluminium (Al) is an inhibition of root elongation. In the present study, short and medium-term effects of Al treatment (20 mM) on root growth and Al accumulation of two common bean (Phaseolus vulgaris L.) genotypes, VAX-1 (Al- sensitive) and Quimbaya (Al-resistant), were studied. Root elongation of both genotypes was severely inhibited during the first

Andres F. Rangel; Idupulapati M. Rao; Walter J. Horst

2007-01-01

286

Effect of particle size of SiC in aluminium matrix on workability and strain hardening behaviour of P\\/M composite  

Microsoft Academic Search

A complete experimental investigation on workability behaviour of the Al–SiC has been carried out during cold upsetting. The present study has been performed to evaluate the effect of particle size of silicon carbide addition in P\\/M preforms of Al–SiC composite on workability studies. The material studied in this paper is aluminium with SiC reinforcement. SiC content has been varied from

R. Narayanasamy; T. Ramesh; M. Prabhakar

2009-01-01

287

Light weight cellular structures based on aluminium  

SciTech Connect

An interesting form of lightweight material which has emerged in the past 2 decades is metallic foam. This paper deals with the basic concepts of making metallic foams and a detailed study of foams produced from Al-SiC. In addition, some aspects of cellular solids based on honeycomb structures are outlined including the concept of producing both two-phase foams and foams with composite walls.

Prakash, O. [Indian Inst. of Tech., Kanpur (India); Embury, J.D.; Sinclair, C. [McMaster Univ., Hamilton, ON (Canada); Sang, H. [Queen`s Univ., Kingston, ON (Canada); Silvetti, P. [Cordoba Univ. Nacional (Argentina). Facultad de Ciencias Exactas, Fisicas y Naturales

1997-02-01

288

Evaluation of certain food additives and contaminants.  

PubMed

This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of various food additives with a view to recommending acceptable daily intakes (ADIs) and to preparing specifications for identity and purity. The Committee also evaluated the risk posed by a number of food contaminants, with the aim of advising on risk management options for the purpose of public health protection. The first part of the report contains a general discussion of the principles governing the toxicological evaluation and assessments of intake of food additives (in particular, flavouring agents) and contaminants. A summary follows of the Committee's evaluations of technical, toxicological and intake data for certain food additives (annatto extracts, natamycin, propyl paraben, synthetic lycopene and lycopene from Blakeslea trispora and food contaminants (aluminium, 3-chloro-1,2-propanediol, 1,3-dichloro-2-propanol and methylmercury). Specifications for the following food additives were revised: carob bean gum, guar gum, titanium dioxide and zeaxanthin. Annexed to the report are tables summarizing the Committee's recommendations for intakes and toxicological evaluations of the food additives and contaminants considered. PMID:17687927

2007-01-01

289

Integration of Eastern Europe and Russia in the World Market: Consequences for the Aluminium Production in Norway.  

National Technical Information Service (NTIS)

This report analyzes the consequences for the aluminium production in Norway from the reforms in the former centrally planned economics. The report is organised in the following way. Chapter 2 presents the latest developments in the world aluminium market...

M. D. Riiser

1995-01-01

290

Fluorometric determination of serum and urinary aluminium with 8-quinolinol by kinetic-differentiation-mode micellar chromatography  

Microsoft Academic Search

A new fluorometric method has been developed for the determination of aluminium with 8-quinolinol by kinetic-differentiation-mode micellar chromatography. The proposed method enabled the determination of aluminium down to 1 ?g\\/l in human serum and urine without preliminary deproteinization. The most remarkable point of this method is that only aluminium ion selectively responds among metal ions. The complex formation of aluminium

Makoto Sato; Hajime Yoshimura; Tetsuo Shimmura; Hideki Obi; Shin-ichi Hatakeyama; Emiko Kaneko; Hitoshi Hoshino; Takao Yotsuyanagi

1997-01-01

291

On the influence of ion-induced surface modification on localized corrosion of aluminium  

Microsoft Academic Search

Modern surface modification techniques offer means for changing properties of materials related to physical or chemical reactions at or near the surface. Thus the corrosion behaviour of metals can be affected by applying this method. The influence of Mg and Cr ion implantation and coatings with Zr or Si thin films on the corrosion properties of aluminium and an aluminium

R. Emmerich; G. K. Wolf; H. Buhl; R. Braun

1995-01-01

292

Damage and failure processes of hybrid joints: Adhesive bonded aluminium plates reinforced by rivets  

Microsoft Academic Search

The aim of this article was the analysis of the damage and failure behaviour of the hybrid joint consisted of: three aluminium plates (adherents), the polyurethane adhesive (two laps 40×40mm) and reinforced by five rivets. The ABAQUS programme was used to simulate the tensile strength in this type of joint. The 3D numerical analysis includes modelling of: the aluminium plates,

T. Sadowski; P. Golewski; E. Zarzeka-Raczkowska

2011-01-01

293

Bacopa monniera prevents from aluminium neurotoxicity in the cerebral cortex of rat brain  

Microsoft Academic Search

Bacopa monniera is a perennial herb, and is used as a nerve tonic in äyurveda, a traditional medicinal system in India. Aluminium-induced neurotoxicity is well known and different salts of aluminium have been reported to accelerate oxidative damage to biomolecules like lipids, proteins and nucleic acids. The objective of the present study was to investigate whether Bacopa monniera could potentially

Amar Jyoti; Pallavi Sethi; Deepak Sharma

2007-01-01

294

Gum arabic as a potential corrosion inhibitor for aluminium in alkaline medium and its adsorption characteristics  

Microsoft Academic Search

Purpose – To investigate the inhibitive effect of gum arabic (GA) for the corrosion of aluminium in alkaline (NaOH) medium and determine its adsorption characteristics. The present work is another trial to find a cheap and environmentally safe inhibitor for aluminium corrosion. Design\\/methodology\\/approach – The inhibition efficiency (%I) has been evaluated using the hydrogen evolution (via the gasometric assembly) and

S. A. Umoren; I. B. Obot; E. E. Ebenso; P. C. Okafor; O. Ogbobe; E. E. Oguzie

2006-01-01

295

Successful treatment of acute aluminium phosphide poisoning: possible benefit of coconut oil  

Microsoft Academic Search

Aluminium phosphide is used to control rodents and pests in grain storage facilities. It produces phosphine gas, which is a mitochondrial poison. Unfortunately, there is no known antidote for aluminium phosphide intoxication, but our recent experience with a case showed that rapid prevention of absorption by coconut oil might be helpful. In the present case, we used the same protocol

Shahin Shadnia; Mojgan Rahimi; Abdolkarim Pajoumand; Mohammad-Hosein Rasouli; Mohammad Abdollahi

2005-01-01

296

Effect of aluminium solids and chlorine on cold water pitting of copper  

Microsoft Academic Search

Both aluminium solids and chlorine are often present in potable water systems, but their effect on copper corrosion and pitting is not well understood. Circumstantial evidence from one system with copper pitting problems suggested that high chlorine residuals and aluminium solids might be contributing factors. To test this hypothesis, a series of experiments were conducted to examine their effect on

Jason C. Rushing; Marc Edwards

2004-01-01

297

Extrusion Die Design and Process Simulation of High Strength Aluminium Alloy  

Microsoft Academic Search

Aluminium alloy 7075 is an excellent metal with the features of high strength and light weight. The solid extruded parts of AL 7075 are commonly used in the structure members of airplanes and bicycles. The seamless tubes of AL 7075 are also used, while tubes with welding line (seamed) are mainly made by the other types of aluminium alloy. This

Jinn-Jong Sheu; Yan-Hong Chen; Guan-Cheng Su

2011-01-01

298

MODELLING OF THERMAL PROCESSES IN A DISSYMMETRICAL WELDED CAST ALUMINIUM DESIGNS  

Microsoft Academic Search

Number of constructions, produced from eutectic silumins are continually increasing, therefore problem of their welding became very actual. Eutectic aluminium - silicon alloys are sensitive to changes of a welding thermal cycle. These cast aluminium alloys constructions after welding have large residual stresses, and mechanical properties of welded joint deteriorate. It is difficult to define welding regime in case of

N. Višniakov; D. Š?ekaturovien?; O. ?ernaš?jus

299

Aluminium based adjuvants and their effects on mitochondria and lysosomes of phagocytosing cells.  

PubMed

Aluminium oxyhydroxide, Al(OH)3 is one of few compounds approved as an adjuvant in human vaccines. However, the mechanism behind its immune stimulating properties is still poorly understood. In vitro co-culture of an aluminium adjuvant and the human monocytic cell line THP-1 resulted in reduced cell proliferation. Inhibition occurred at concentrations of adjuvant several times lower than would be found at the injection site using a vaccine formulation containing an aluminium adjuvant. Based on evaluation of the mitochondrial membrane potential, THP-1 cells showed no mitochondrial rupture after co-culture with the aluminium adjuvant, instead an increase in mitochondrial activity was seen. The THP-1 cells are phagocytosing cells and after co-culture with the aluminium adjuvant the phagosomal pathway was obstructed. Primary or early phagosomes mature into phagolysosomes with an internal pH of 4.5 - 5 and carry a wide variety of hydrolysing enzymes. Co-culture with the aluminium adjuvant yielded a reduced level of acidic vesicles and cathepsin L activity, a proteolytic enzyme of the phagolysosomes, was almost completely inhibited. THP-1 cells are an appropriate in vitro model in order to investigate the mechanism behind the induction of a phagocytosing antigen presenting cell into an inflammatory cell by aluminium adjuvants. Much information will be gained by investigating the phagosomal pathway and what occurs inside the phagosomes and to elucidate the ultimate fate of phagocytosed aluminium particles. PMID:23992993

Ohlsson, Lars; Exley, Christopher; Darabi, Anna; Sandén, Emma; Siesjö, Peter; Eriksson, Håkan

2013-08-09

300

Brazing of A5056 aluminium alloy with the aid of ultrasonic vibration using Ag filler metal  

Microsoft Academic Search

In order to produce a high strength brazed joint of A5056 aluminium alloy containing magnesium of about 5 mass%, the authors applied a flux-free brazing method with the aid of ultrasonic vibration to the aluminium alloy by selecting pure Ag foil as brazing filler metal and examined the effect of brazing conditions on the joint properties. The main results obtained

Takehiko Watanabe; Haruhiko Adachi; Atsushi Yanagisawa

2010-01-01

301

Protective effect of curcumin ( Curcuma longa), against aluminium toxicity: Possible behavioral and biochemical alterations in rats  

Microsoft Academic Search

Aluminium is a potent neurotoxin and has been associated with Alzheimer's disease (AD) causality for decades. Prolonged aluminium exposure induces oxidative stress and increases amyloid beta levels in vivo. Current treatment modalities for AD provide only symptomatic relief thus necessitating the development of new drugs with fewer side effects. The aim of the study was to demonstrate the protective effect

Anil Kumar; Samrita Dogra; Atish Prakash

2009-01-01

302

Modelling the capacitance of d.c. etched aluminium electrolytic capacitor foil  

Microsoft Academic Search

A model for the capacitance of anode foil used in aluminium electrolytic capacitors is compared with experimental data for commercial foils from two different manufacturers. These foils are obtained by anodic electrochemical etching to produce a porous tunnel etched structure, followed by formation of a layer of dielectric aluminium oxide in the pores. Data for the density and size of

D. G. W. Goad; H. Uchi

2000-01-01

303

Image analysis of periodic rain accelerated corrosion of aeronautical aluminium alloys  

Microsoft Academic Search

Periodic rain tests have been carried out for simulating atmospheric corrosion of aeronautical aluminium alloys. A digital image preprocessing and analysis method based on wavelet transformation was used to study the corrosion morphology of aluminium alloys samples, through which an image feature parameter ? was extracted and discussed. The influences of orthogonal experiment parameters on acceleration were analyzed according to

Lei Tao; Shizhe Song; Shouyan Wang; Xiaoyun Zhang; Ming Liu; Feng Lu

2008-01-01

304

Influence of Aluminium on mineral uptake by Beech and spruce roots.  

National Technical Information Service (NTIS)

Acidification of forest soils leads to increased aluminium levels in the soil solution. The effect of aluminium on mineral uptake and growth were studied on small plants of beech and Norway spruce. Plants were cultivated in sand (spruce) or nutrient solut...

H. Asp

1991-01-01

305

A NOVEL CRUCIBLE METAL TREATMENT PRO CESS FOR IMPURITY REMOVAL lN SECONDARY ALUMINIUM  

Microsoft Academic Search

Treatment of aluminium in crucibles is weil established in the aluminium smelting industry as a very efficient technology to remove alkali elements such as lithium and sodium. The utilization of crucibles is a common tool in remelt and recycling plants to transport metal recovered from dross recycling and scrap melting operations. ln these cases, the metal is often contaminated with

Gaston Riverin; Jean-François Bilodeau; Claude Dupuis

306

Characterization of refuse powders from an aluminium recovery plant for ceramic purposes  

Microsoft Academic Search

The fusion process of aluminium scraps produces slags which still contain a high amount of the metal, thus they may be remelted for a further recovery of aluminium. To this purpose, the slags were previously ground to obtain an appropriate grain size, approximately 0.1 to 1 cm. The coal-containing fine and light powders formed during the milling constitute the socalled

C. Fiori; B. Fabbri

1986-01-01

307

Aluminium Foil as a Food Packaging Material in Comparison with Other Materials  

Microsoft Academic Search

Aluminium foil is an important material in laminates and has wide application in food packaging. Its barrier function against the migration of moisture, oxygen and other gases, and volatile aroma, as well as against the impact of light is generally higher than any plastic laminate material. Therefore, aluminium foil is used in the laminates when insufficient barrier properties are the

Manuela Lamberti; Felix Escher

2007-01-01

308

Effect of tool geometry on microstructure and static strength in friction stir spot welded aluminium alloys  

Microsoft Academic Search

The effect of tool geometry on microstructure and static strength in friction stir spot welds of 6061 aluminium alloy sheets was studied. Tools with three different probe lengths were used to join the aluminium sheet with different tool rotational speeds and tool holding times. The weld microstructures varied significantly depending on probe length, tool rotational speed and tool holding time.

Yasunari Tozaki; Yoshihiko Uematsu; Keiro Tokaji

2007-01-01

309

Are aluminium potroom workers at increased risk of neurological disorders?  

PubMed Central

OBJECTIVE: To determine whether long term potroom workers in an aluminium smelter are at increased risk of neurological disorders. METHODS: Cross sectional study of 63 current and former aluminium potroom workers first employed before 1970 and with at least 10 years of service. A group of 37 cast house and carbon plant workers with similar durations of employment and starting dates in the same smelter were used as controls. The prevalence of neurological symptoms was ascertained by questionnaire. Objective tests of tremor in both upper and lower limbs, postural stability, reaction time, and vocabulary were conducted. All subjects were examined by a neurologist. RESULTS: No significant differences in age, race, or education were found between the two groups. Although the potroom group had higher prevalences for all but one of the neurological symptoms, only three odds ratios (ORs) were significantly increased; for incoordination (OR 10.6), difficulty buttoning (OR 6.2), and depression (OR 6.2). Tests of arm or hand and leg tremor in both the visible and non-visible frequencies did not show any significant differences between the two groups. Testing of postural stability showed no definitive pattern of neurologically meaningful differences between the groups. There were no significant differences between the two groups in reaction time, vocabulary score, or clinical neurological assessment. CONCLUSIONS: The objective measures of neurological function provided little support for the finding of increased neurological symptom prevalences in the potroom workers, although increased symptoms may be an indicator of early, subtle neurological changes. The results provide no firm basis for concluding that neurological effects among long term potroom workers are related to the working environment, in particular aluminium exposure, in potrooms. These findings should be treated with caution due to the low participation of former workers and the possibility of information bias in the potroom group.

Sim, M; Dick, R; Russo, J; Bernard, B; Grubb, P; Krieg, E; Mueller, C; McCammon, C

1997-01-01

310

Chloroplastic glutamine synthetase is activated by direct binding of aluminium.  

PubMed

Acidification of soils may release water soluble, toxic aluminium species from clay minerals. Al interferes with a wide range of physical and cellular processes. Glutamine synthetase (GS, EC 6.3.1.2) is the key enzyme of primary N assimilation, as well as ammonia reassimilation and detoxification. Plant GS requires two magnesium ions per subunit for activity, which makes GS a potential target of metal stress. The objective of this investigation was to prove that Al from an organic metal complex is able to activate GS, and Al becomes bound to the polypeptide structure of the GS molecule. Aluminium(III)-nitrilotriacetic acid complex (Al(III)NTA) activated the GS prepared from wheat (Triticum aestivum L.) leaves, as Al(3+) did in vivo, but could not functionally substitute magnesium ions, which were also necessary for the activity in the in vitro GS assay. GS2 was isolated by non-denaturing polyacrylamide gel electrophoresis, and the Al and Mg content of the enzyme was determined by inductively coupled plasma atomic emission spectroscopy. The GS octamer remained intact and contained Mg(2+) bound to its specific sites after the electrophoretic separation. Al was detected in the Al(III)NTA-treated sample bound to the structure of the enzyme protein, potentially occupying one of the specific metal-binding sites of the subunits. Our results indicate that the activatory effect of the Al(III)NTA complex is because of specific binding of aluminium to the polypeptide chain of GS2, however presence of magnesium at least on one of the metal-binding sites is essential to the active state of the enzyme. PMID:19121098

Pécsváradi, Attila; Nagy, Zoltán; Varga, Anikó; Vashegyi, Agnes; Labádi, Imre; Galbács, Gábor; Zsoldos, Ferenc

2009-01-01

311

Hexaaqua-aluminium(III) tris-(methane-sulfonate).  

PubMed

The title compound, [Al(H(2)O)(6)](CH(3)SO(3))(3) (common name: aluminium methane-sulfonate hexa-hydrate), was crystallized from an aqueous solution prepared by the precipitation reaction of aluminium sulfate and barium methane-sulfonate. Its crystal structure is the first of the boron group methane-sulfonates to be determined. The characteristic building block is a centrosymmetric unit containing two hexa-aqua-aluminium cations that are connected to each other by two O atoms of the -SO(3) groups in an O-H?O?H-O sequence. Further O-H?O hydrogen bonding links these blocks in orthogonal directions - along [010] forming a double chain array, along [10-1] forming a layered arrangement of parallel chains and along [101] forming a three-dimensional network. As indicated by the O?O distances of 2.600?(3)-2.715?(3)?Å, the hydrogen bonds are from medium-strong to strong. A further structural feature is the arrangement of two and four methyl groups, respectively, establishing 'hydro-phobic islands' of different size, all positioned in a layer-like region perpendicular to [101]. The only other building block within this region is one of the -SO(3) groups giving a local connection between the hydro-philic structural regions on both sides of the 'hydro-phobic' one. Thermal analysis indicates that a stepwise dehydration process starts at about 413?K and proceeds via the respective penta- and dihydrate until the compound completely decomposes at about 688?K. PMID:22904782

Trella, Thomas; Frank, Walter

2012-07-28

312

Hexaaqua-aluminium(III) tris-(methane-sulfonate)  

PubMed Central

The title compound, [Al(H2O)6](CH3SO3)3 (common name: aluminium methane­sulfonate hexa­hydrate), was crystallized from an aqueous solution prepared by the precipitation reaction of aluminium sulfate and barium methane­sulfonate. Its crystal structure is the first of the boron group methane­sulfonates to be determined. The characteristic building block is a centrosymmetric unit containing two hexa­aqua­aluminium cations that are connected to each other by two O atoms of the –SO3 groups in an O—H?O?H—O sequence. Further O—H?O hydrogen bonding links these blocks in orthogonal directions – along [010] forming a double chain array, along [10-1] forming a layered arrangement of parallel chains and along [101] forming a three-dimensional network. As indicated by the O?O distances of 2.600?(3)–2.715?(3)?Å, the hydrogen bonds are from medium–strong to strong. A further structural feature is the arrangement of two and four methyl groups, respectively, establishing ‘hydro­phobic islands’ of different size, all positioned in a layer-like region perpendicular to [101]. The only other building block within this region is one of the –SO3 groups giving a local connection between the hydro­philic structural regions on both sides of the ‘hydro­phobic’ one. Thermal analysis indicates that a stepwise dehydration process starts at about 413?K and proceeds via the respective penta- and dihydrate until the compound completely decomposes at about 688?K.

Trella, Thomas; Frank, Walter

2012-01-01

313

Creep behaviour of aluminium strengthened by fine aluminium carbide particles and reinforced by silicon carbide particulates — DS Al–SiC\\/Al 4C 3 composites  

Microsoft Academic Search

Creep behaviour of aluminium strengthened by fine aluminium carbide particles and reinforced by silicon carbide particulates is investigated. For comparison, the results for two dispersion strengthened (DS) AlC alloys denoted DS AlC1 and DS AlC2 are presented. (C1 and C2 mean the contents of carbon in wt% which define the volume fractions of Al4C3 particles in DS AlC alloys as

S. J. Zhu; L. M. Peng; Q. Zhou; Z. Y. Ma; K. Kucha?ová; J. ?adek

2000-01-01

314

Creep behaviour of aluminium strengthened by fine aluminium carbide particles and reinforced by silicon carbide particulates — DS Al–SiC\\/Al 4C 3 composites  

Microsoft Academic Search

Creep behaviour of aluminium strengthened by fine aluminium carbide particles and reinforced by silicon carbide particulates is investigated. For comparison, the results for two dispersion strengthened (DS) AlC alloys denoted DS AlC1 and DS AlC2 are presented. (C1 and C2 mean the contents of carbon in wt% which define the volume fractions of Al4C3 particles in DS AlC alloys as

S. J Zhu; L. M Peng; Q Zhou; Z. Y Ma; K Kucha?ová; J ?adek

1999-01-01

315

Comparative study of aluminium-doped zinc oxide and ruthenium–aluminium co-doped zinc oxide by magnetron co-sputtering  

Microsoft Academic Search

Highly oriented polycrystalline aluminium-doped (Al-doped) and ruthenium–aluminium (Ru–Al) co-doped zinc oxide are prepared on borosilicate glass and polycarbonate (PC) substrates by co-sputtering at room temperature. To investigate the effect of Ru doping, co-sputtering is achieved by varying the sputtering power of Ru target while keeping the sputtering target power of Al-doped zinc oxide unchanged. Atomic force microscopy (AFM) data shows

L. M. Wong; S. J. Wang; W. K. Chim

2010-01-01

316

Degradation phenomena in gallium aluminium arsenide stripe geometry lasers  

NASA Astrophysics Data System (ADS)

Gallium aluminium arsenide CW stripe lasers are capable of operating for at least several years at room temperature. However, both bulk and surface degradation still occur. Point defects incorporated during processing and strain associated with oxide isolation layers can influence bulk degradation; facet protection modifies surface effects. At higher temperatures, bond deterioration and localized bulk effects are more important than at room temperature. In order to justify the validity of temperature overstress testing, degradation mechanisms must be shown to be the same under operational and overstress conditions. Statistical analysis of data suggests that higher temperature degradation data cannot automatically be extrapolated via an Arrhenius-type relationship to yield meaningful operational lives.

Newman, D. H.; Ritchie, S.

1980-03-01

317

Mechanism of aluminium bio-mineralization in the apoferritin cavity  

NASA Astrophysics Data System (ADS)

Many experimental evidences point out the correlation between the presence of aluminum-ferritin complex and neursopathological disorders. In these complexes, two different ranges of Aluminium (Al) atoms are usually found, i.e., just few atoms or several hundreds. Here, we investigated the in-vitro Al-apoferritin binding, with the aim to elucidate the mechanism behind the formation of Al-ferritin complexes in-vivo. To this purpose, we studied the mineralization of Al in its ionic and complexed form with citrate demonstrating that high Al levels found in clinical studies can be obtained only conveying Al by small physiological ligands.

Chiarpotto, M.; Ciasca, G.; Vassalli, M.; Rossi, C.; Campi, G.; Ricci, A.; Bocca, B.; Pino, A.; Alimonti, A.; De Sole, P.; Papi, M.

2013-08-01

318

New investigations on hematoxylin, hematein, and hematein-aluminium complexes. II. Hematein-aluminium complexes and hemalum staining.  

PubMed

The absorption spectra of hematein-aluminium solutions have been recorded at various concentrations and pH values; the solutions were prepared using analytically pure hematein and potassium alum as aluminium source. In aqueous solution, four different hematein-aluminium complexes could be distinguished by absorption spectroscopy. In weakly acidic media we observed the violet 1:1 and 1:2 complexes HmAl (VII) and HmAl2(3) (VIII), and in strongly acidic solution the red 1:1 complex HmAl2 (IX). Whereas, in weakly alkaline solution the blue 1:1 complex HmAl0 (X) was detected. By change of the pH value the complexes were mutual interconverted. The dye complexes were characterized by their absorption spectra and molar extinction coefficients. We have stained HeLa cells with the complex solutions under different experimental conditions. In all cases the nuclear staining was intense whereas the staining of the cytoplasm was weak. The microspectra of the stained nuclei were recorded and compared with the absorption spectra of the complexes in solution. Thus it was possible to identify the bound dye species. After staining in acidic media, the cells were red to red-violet depending on the reaction conditions. The three cationic dye species VII, VIII, and IX were bound in varying amounts. After blueing in weakly acidic media or in water, only the violet dye complex VII was detected whereas, after blueing in weakly alkaline media, only the blue complex X has been observed. Enzymatic digestion experiments have shown that the dye complexes in the nuclei were bound to DNA while those in the cytoplasm and nucleoli were bound to RNA. The binding between the dye complexes and the nucleic acids is discussed. PMID:1717413

Bettinger, C; Zimmermann, H W

1991-01-01

319

The sensitive and selective determination of aluminium by spectrofluorimetric detection after complexation with N-o-vanillidine-2-amino-p-cresol.  

PubMed

A simple, easy to use and selective spectrofluorimetric method for the determination of trace levels of aluminium has been developed. A new Schiff base, N-o-vanillidine-2-amino-p-cresol (OVAC), has been synthesized and its fluorescence activity with aluminium investigated. Based on this chelation reaction, a spectrofluorimetric method has been developed for the determination of aluminium in samples buffered at pH 4.0 using acetic acid-sodium acetate. The chelation reaction between Al(iii) and N-o-vanillidine-2-amino-p-cresol was very fast, requiring only 20 min at room temperature to complex completely. The excitation and emission wavelengths were 423.0 and 553.0 nm, respectively, at which the OVAC-Al complex gave the maximum fluorescence intensity at pH 4.0 in a 50% ethanol-50% water medium. The interference from fluoride ions was minimized by the addition of Be(2+). Other ions were found not to interfere at the concentrations likely to be found in natural waters. Under these conditions, the calibration plot was linear up to 1000 microg L(-1) (r = 0.999). The limit of detection (3sigma) for the determination of Al(iii) was 0.19 microg L(-1) and the precision for multiple determinations of 3 ng mL(-1) Al(iii) prepared in ultra-pure water was found to be 0.29% (n = 16). The Schiff base ligand could be used to determine ultra-trace aluminium from natural waters. Analysis of environmental certified reference materials showed good agreement with the certified values. The procedure was found to be equally applicable to both fresh water and saline solutions (including sea water) using either normal external calibration or the standard additions method. PMID:17726561

Kara, Derya; Fisher, Andrew; Hill, Steve J

2007-07-06

320

Surfacing weld metal properties of aluminium alloys with Al?Cu cored wire: Surfacing of aluminium alloys (3rd report)  

Microsoft Academic Search

This paper describes an investigation of the properties of surfacing weld metals produced by the MIG and TIG processes using newly developed 1.2 mm dia. Al?Cu seamless cored electrode wires. Three types of Al?Cu cored wires with Cu contents of 40%, 45%, and 70% were tested on type A1050P (Al), A5083P (Mn?Mg?Al), A7075P (Cu?Mg?Zn?Al), and AC4B (Si?Cu?Zn, cast) aluminium alloy

Y. Kanbe; Y. Nakada; S. Kurihana; H. Koike; T. Miyake

1994-01-01

321

Fabrication of superhydrophobic aluminium alloy surface with excellent corrosion resistance by a facile and environment-friendly method  

NASA Astrophysics Data System (ADS)

This work develops a facile and environment-friendly method for preparing the superhydrophobic aluminium alloy surface with excellent corrosion resistance. The superhydrophobic aluminium alloy surface is fabricated by the boiling water treatment and stearic acid (STA) modification. Results show that the boiling water treatment endows the aluminium alloy surface with a porous and rough structure, while STA modification chemically grafts the long hydrophobic alkyl chains onto the aluminium alloy surface. Just grounded on the micro- and nano-scale hierarchical structure along with the hydrophobic chemical composition, the superhydrophobic aluminium alloy surface is endued the excellent corrosion resistance.

Feng, Libang; Che, Yanhui; Liu, Yanhua; Qiang, Xiaohu; Wang, Yanping

2013-10-01

322

Aluminium nitride films prepared by reactive magnetron sputtering  

NASA Astrophysics Data System (ADS)

The exceptional properties of aluminium nitride make this material a very promising candidate for a variety of technological applications. In this paper we report our work on the preparation of thin films of aluminium nitride by reactive DC and RF magnetron sputtering. The physical and electrical properties of the films were studied as a function of the preparation conditions: concentration of nitrogen in the reactive gas mixture, the substrate temperature, the plasma power and the horizontal distance from the centre of the target. X-ray diffraction data indicated that highly oriented polycrystalline films could be fabricated. Rutherford backscattering and nuclear reaction analysis showed that nearly stoichiometric films could be prepared using nitrogen concentrations greater than 50%. For the DC plasma process, bombardment of the growing film plays a very significant role. The film growth mechanism was found to be very different for the RF plasma. The nuclear analysis of the films prepared at different lateral distances, together with measurements of the substrate potential, permitted modelling of the film formation process for both the DC and RF plasmas.

Muhl, S.; Zapien, J. A.; Mendez, J. M.; Andrade, E.

1997-08-01

323

Experimental study of friction in aluminium bolted joints  

NASA Astrophysics Data System (ADS)

This study aims at developing an experimental tool useful to define accurately the friction coefficients in bolted joints and, therefore, at relating precisely the tightening torque to the bolt preloading force in some special components used in front motorbike suspensions. The components under investigation are some clamped joints made of aluminium alloy. The preloading force is achieved by applying a torque wrench to the bolt head. Some specific specimens have been appropriately designed and realized in order to study the tribological aspects of the tightening phase. Experimental tests have been performed by applying the Design of Experiment (DOE) method in order to obtain a mathematical model for the friction coefficients. Three replicas of a full factorial DOE at two levels for each variable have been carried out. The levels include cast versus forged aluminium alloy, anodized versus spray-painted surface, lubricated versus unlubricated screw, and first tightening (fresh unspoiled surfaces) versus sixth tightening (spoiled surfaces). The study considers M8x1.25 8.8 galvanized screws.

Croccolo, D.; de Agostinis, M.; Vincenzi, N.

2010-06-01

324

High-Rate Compaction of Aluminium Alloy Foams  

SciTech Connect

The response of aluminium foams to impact can be categorised according to the impact velocity. Tests have been carried out at a range of impact velocities from quasi-static to velocities approaching the speed of sound in the foam. Various experimental arrangements have been employed including pneumatic launcher tests and plate impact experimants at velocities greater than 1000 m s-1. The quasi-static compression behaviour was approximately elastic, perfectly-plastic, locking. For static and dynamic compression at low impact velocities the deformation pattern was through the cumulative multiplication of discrete, non-contiguous crush bands. Selected impact tests are presented here for which the impact velocity is less than the velocity of sound, but above a certain critical impact velocity so that the plastic compression occurs in a shock-like manner and the specimens deform by progressive cell crushing. Laboratory X-ray microtomography has been employed to acquire tomographic datasets of aluminium foams before and after tests. The morphology of the underformed foam was used as the input dataset to an Eulerian code. Hydrocode simulations were then carried out on a real microstructure. These simulations provide insight to mechanisms associated with the localization of deformation.

Harrigan, J. J.; Hung, Y.-C.; Tan, P. J.; Bourne, N. K.; Withers, P. J.; Reid, S. R. [University of Manchester, PO Box 88, Sackville Street, Manchester M60 1QD (United Kingdom); Millett, J. C. F. [Defence Academy of the UK, Cranfield University, Shrivenham, Swindon, SN6 8LA (United Kingdom); Milne, A. M. [Fluid Gravity Engineering, 83 Market Street, St. Andrews, Fife, KY16 9NX (United Kingdom)

2006-07-28

325

Titanium aluminide formation in Ti implanted aluminium alloy  

NASA Astrophysics Data System (ADS)

Ion implantation has been extensively used for modifying the surfaces of engineering materials. In the present report, the implantation of type 6061 aluminium alloy with Ti ions has been investigated as a function of dose and substrate temperature. Retained doses in the range 0.8-6 × 1017 ions cm-2 were studied in order to examine the effect of Ti concentration on intermetallic compound stoichiometry. The formation of titanium aluminides following implantation was monitored by means of glancing angle X-ray diffraction (GAXRD) while the Ti depth profiles were obtained from Rutherford backscattering (RBS) analysis. Peak concentrations of the implanted Ti were found to vary with substrate temperature. At the lower end of the range studied, high peak concentrations of Ti were observed and GAXRD analysis indicated the presence of AlTi3. In contrast, substrate temperatures of ~400°C yielded broader implant distributions, extending to greater depths and with lower peak concentrations of implant. These were attributed to temperature induced diffusional effects which favoured the formation of an aluminium rich intermetallic compound Al3Ti.

Evans, P. J.; Knight, S. T.; Samandi, M.

1996-12-01

326

Aluminium-induced nanocrystalline Ge formation at low temperatures  

NASA Astrophysics Data System (ADS)

The present work contributes to establishing the role of hydrogenation and of the substrates in the aluminium-induced crystallization process of amorphous germanium layers. For such a purpose, four series of a-Ge(Al) samples, deposited under identical nominal conditions, were studied: hydrogenated samples, H-free samples, and samples deposited on crystalline silicon and on glass substrates, respectively. On purpose, the impurity concentration was kept at a doping level (10-5<[Al/Ge]<2 × 10-3). Furthermore, the films were submitted to isochronal cumulative thermal annealing in the 200-550 °C range. Raman scattering spectroscopy was used to characterize the crystallization process. The role of Al impurity as a precursor seed for the crystallization of a-Ge:H has been clearly established, confirming that the metal-induced crystallization (MIC) phenomenon occurs at an atomic level. Moreover, it has been found that hydrogenation and the periodic nature of the substrate play a fundamental role in the appearance of crystal seeds at low temperatures. The evolution of crystallization with annealing temperature and the analysis of the distribution of crystallite sizes indicate that the formation of crystal seeds occurs at the amorphous film-substrate interface. The importance of fourfold-coordinated aluminium as the embryo of nanocrystal formation is discussed.

Muniz, L. R.; Ribeiro, C. T. M.; Zanatta, A. R.; Chambouleyron, I.

2007-02-01

327

Perforation of aluminium foam core sandwich panels under impact loading  

NASA Astrophysics Data System (ADS)

This paper reports an original inverse perforation tests on foam core sandwich panels under impact loading. The key point is the use of an instrumented Hopkinson pressure bar as a perforator and at the same time a measuring device. It aims at a high quality piercing force record during the whole perforation process, which is a lack of common free-flying projectile - target testing schemes. This new testing arrangement allows for the measurement of piercing force-displacement curves under quasi-static and impact loadings of sandwich samples, which is made of 40?mm AlSi7Mg0.5 Cymat foam cores and 0.8?mm thick 2024 T3 aluminium sheet as top and bottom skins. Compared with quasi-static top skin peak loads (the maximal load before the perforation of top skins) obtained under same geometric and clamping conditions and even in the case that the used foam core (Cymat) and aluminium skin sheet are known and have been confirmed rate insensitive, a significant enhancement under impact loading (25%) of the top skin peak load is found.

Elnasri, I.; Zhao, H.; Girard, Y.

2006-08-01

328

Catalytic spectrophotometric determination of trace aluminium with indigo carmine  

NASA Astrophysics Data System (ADS)

A new catalytic spectrophotometric method is described for the determination of trace amounts of Al(III). The methods based on catalytic action of Al(III) on the oxidation of indigo carmine (IC) by ammonium persulfate in hexamethylene tetramine-hydrochloric acid ((CH 2) 6N 4-HCl) buffer medium (pH 5.4) and in the presence of surfactant—TritonX-100. The effects of some factors on the reaction speed were investigated. Aluminium concentration is linear for 0-1.2 × 10 -7 g/ml in this method. The detection limit of the proposed method is 1.96 × 10 -8 g/ml. Most of the foreign ions except for Cu(II), Fe(III) do not interfere with the determination, and the interference of Cu(II) and Fe(III) in this method can be removed by extraction with sodium diethyldithiocarbamate-carbon tetrachloride (DDTC-CCl 4). This system is a quasi-zero-order reaction for Al(III), but it is a quasi-first-order reaction for IC. The apparent rate constant is 2.62 × 10 -5 s -1 and the apparent activation energy is 6.60 kJ/mol in the system. The proposed method was applied to the determination of trace aluminium(III) in real samples with satisfactory results.

Zheng, Huai-Li; Xiong, Wen-Qiang; Gong, Ying-Kun; Peng, De-Jun; Li, Ling-Chun

2007-04-01

329

Improved high temperature properties of SiC-ceramics sintered with Lu 2O 3-containing additives  

Microsoft Academic Search

Liquid-phase (LPS) sintered silicon carbide ceramics with additive systems containing aluminium nitride and rare earth oxides in combination are candidate materials for good high temperature performance in terms of creep behaviour and oxidation resistance. In the present work, creep testing in four-point bending geometry and scanning electron microscopic observation of oxidized surfaces were performed on yttrium and lutetium sesquioxide containing

Koushik Biswas; Georg Rixecker; Fritz Aldinger

2003-01-01

330

Analysis of Machining Characteristics in Additive Mixed Electric Discharge Machining of Nickel-Based Super Alloy Inconel 718  

Microsoft Academic Search

Additive mixed electric discharge machining (AEDM) is a recent innovation for enhancing the capabilities of electrical discharge machining process. The objective of present research work is to study the influence of operating process input parameters on machining characteristics of nickel-based super alloy (Inconel 718) in aluminium AEDM with copper electrode. The effectiveness of AEDM process on Inconel is evaluated in

Anil Kumar; Sachin Maheshwari; Chitra Sharma; Naveen Beri

2011-01-01

331

Fluorometric determination of serum and urinary aluminium with 8-quinolinol by kinetic-differentiation-mode micellar chromatography.  

PubMed

A new fluorometric method has been developed for the determination of aluminium with 8-quinolinol by kinetic-differentiation-mode micellar chromatography. The proposed method enabled the determination of aluminium down to 1 microgram/l in human serum and urine without preliminary deproteinization. The most remarkable point of this method is that only aluminium ion selectively responds among metal ions. The complex formation of aluminium in serum with 8-quinolinol was completed within a few minutes at room temperature. The serum matrix and aluminium chelate were separated on a reversed-phase column with an eluent containing acetonitrile, sodium dodecylsulfate, and Triton X-100, and aluminium chelate was detected at Ex 370 nm, Em 504 nm. The values obtained by this method were in good agreement with those of Zeeman graphite-furnace atomic absorption spectrometry. The proposed method will provide a simple and rapid technique for the determination aluminium in medical fields. PMID:9440292

Sato, M; Yoshimura, H; Shimmura, T; Obi, H; Hatakeyama, S; Kaneko, E; Hoshino, H; Yotsuyanagi, T

1997-11-21

332

Continuous flow analysis method for determination of soluble iron and aluminium in ice cores.  

PubMed

Iron and aluminium are the two most abundant metals on the Earth's crust, but they display quite different biogeochemical properties. While iron is essential to many biological processes, aluminium has not been found to have any biological function at all. In environmental studies, iron has been studied in detail for its limiting role in the bioproductivity of high nutrient, low carbon oceanic zones, while aluminium is routinely used as a reference of crustal contributions to atmospheric deposition archives including peat bogs, lacustrine and marine sediments and ice sheets and glaciers. We report here the development of a flow injection analysis technique, which has been optimised for the simultaneous determination of soluble iron and aluminium in polar ice cores. Iron was determined by its catalytic role in the reduction of N,N-dimethyl-p-phenylenediamene (DPD) to a semiquinonic form (DPDQ) and subsequent absorption spectroscopy at 514 nm. Aluminium was determined by spectroscopic analysis of an aluminium-lumogallion complex that exhibits fluorescence at 560 nm. These techniques have been applied to a section of Greenland ice dated to 1729-1733 AD and indicate that volcanism is a source of highly soluble aluminium and iron. PMID:22692592

Spolaor, A; Vallelonga, P; Gabrieli, J; Roman, M; Barbante, C

2012-06-13

333

Drilling fluid additives  

SciTech Connect

The addition of magnesium oxide to a drilling fluid additive comprising bentonite and ferrochrome lignosulfonate, the drilling fluid additive having a pH of about 9.5 to 12, increases the usefulness of such a drilling fluid additive and increases considerably the yield point of the drilling fluid containing this drilling fluid additive.

Forster, J.W.; Roper, L.E.

1980-06-24

334

Aluminium phosphide poisoning: a prospective study of 16 cases in one year.  

PubMed Central

Sixteen patients suffering from aluminium phosphide poisoning were treated during the year from January 1985 to December 1985. These accounted for approximately half the total number of cases of acute poisoning. Profuse vomiting, pain in the upper abdomen and shock were the most common presenting features. Six patients succumbed to their illness. Analysis of various prognostic factors revealed that ingestion of 'unexposed' tablets of aluminium phosphide taken from a freshly opened bottle was associated with a greater risk of fatal outcome. Aluminium phosphide poisoning has become an important matter of public health in parts of India.

Chopra, J. S.; Kalra, O. P.; Malik, V. S.; Sharma, R.; Chandna, A.

1986-01-01

335

The aluminium content of breast tissue taken from women with breast cancer.  

PubMed

The aetiology of breast cancer is multifactorial. While there are known genetic predispositions to the disease it is probable that environmental factors are also involved. Recent research has demonstrated a regionally specific distribution of aluminium in breast tissue mastectomies while other work has suggested mechanisms whereby breast tissue aluminium might contribute towards the aetiology of breast cancer. We have looked to develop microwave digestion combined with a new form of graphite furnace atomic absorption spectrometry as a precise, accurate and reproducible method for the measurement of aluminium in breast tissue biopsies. We have used this method to test the thesis that there is a regional distribution of aluminium across the breast in women with breast cancer. Microwave digestion of whole breast tissue samples resulted in clear homogenous digests perfectly suitable for the determination of aluminium by graphite furnace atomic absorption spectrometry. The instrument detection limit for the method was 0.48?g/L. Method blanks were used to estimate background levels of contamination of 14.80?g/L. The mean concentration of aluminium across all tissues was 0.39?g Al/g tissue dry wt. There were no statistically significant regionally specific differences in the content of aluminium. We have developed a robust method for the precise and accurate measurement of aluminium in human breast tissue. There are very few such data currently available in the scientific literature and they will add substantially to our understanding of any putative role of aluminium in breast cancer. While we did not observe any statistically significant differences in aluminium content across the breast it has to be emphasised that herein we measured whole breast tissue and not defatted tissue where such a distribution was previously noted. We are very confident that the method developed herein could now be used to provide accurate and reproducible data on the aluminium content in defatted tissue and oil from such tissues and thereby contribute towards our knowledge on aluminium and any role in breast cancer. PMID:23870171

House, Emily; Polwart, Anthony; Darbre, Philippa; Barr, Lester; Metaxas, George; Exley, Christopher

2013-06-01

336

Sublethal effects in Atlantic salmon (Salmo salar) exposed to mixtures of copper, aluminium and gamma radiation.  

PubMed

The present study was designed to investigate the effects in presmolt of Atlantic salmon (Salmo salar) exposed to copper (Cu), aluminium (Al) and gamma radiation, individually or in combination. Fish were exposed for 48 h to metals added to lake water; 10, 40 and 80 ?g Cu/L, 250 ?g Al/L and a combination of 40 ?g Cu/L and 250 ?g Al/L. In addition, gamma radiation (4-70 mGy delivered over 48 h) was added as an additional exposure stressor. Selected endpoints were chosen to reveal different toxic mechanisms and included Cu and Al accumulation on gills, blood chemistry and haematological variables (plasma sodium and chloride, haematocrit, glucose), hepatic levels of reduced and oxidised glutathione (GSH and GSSG) and hepatic transcriptional response of glutathione peroxidase (GPx), gamma-glutamylcysteine synthetase (GCS), metallothionein (MT) and ubiquitin. Exposure to Cu alone resulted in gill accumulation of Cu, reduction of plasma ions and increased transcriptional response of GPx, MT and ubiquitin. Exposure to Al alone reduced plasma ion levels but did not affect any of the hepatic biomarkers except for ubiquitin. The combined metal exposure (Cu + Al) altered the GSH levels, however GPx and MT were not affected suggesting a different mode of detoxification in the combined exposure. Gamma radiation appeared to influence GSH and ubiquitin levels. The observed effects seemed to be both stressor and concentration dependent. PMID:22583837

Heier, Lene Sørlie; Teien, Hans Christian; Oughton, Deborah; Tollefsen, Knut-Erik; Olsvik, Pål A; Rosseland, Bjørn Olav; Lind, Ole Christian; Farmen, Eivind; Skipperud, Lindis; Salbu, Brit

2012-05-13

337

Aluminium coated carbon nanotube film for wavelength-selective surface  

NASA Astrophysics Data System (ADS)

We report selective optical reflectance in an aluminium (Al) coated flexible carbon nanotube (CNT) thin film over a wide range of wavelengths (500-2500 nm). Selective-wavelength surface is achieved by coating CNT surfaces with Al thin film that presented a maximum optical reflectivity of ~65% in the infrared region. However, CNT film alone showed a reflectance of 15-20% over a larger range of wavelengths without any structural modification, which has not been realized so far. Moreover, a tailorable reflectance in CNT is shown to be achieved by tuning various parameters, namely, the porosity of the material, angle of an incident light, and refractive index of the materials. Owing to higher infrared reflectivity and thermal diffusivity, Al coated CNT presents a potential for a high efficiency solar collector.

Mukherjee, S.; Suri, A.; Vani, V. K.; Misra, A.

2013-09-01

338

Positron Annihilation Studies of the Subsurface Zone in Aluminium Alloys  

NASA Astrophysics Data System (ADS)

The paper presents positron lifetime studies of the subsurface region of the aluminium cast AK64 alloy containing silicon as a main alloying element after sliding against stainless steel in the pin-on-disc tester. The subsurface zone of the depth exceeding 150 ?m has been detected. The scanning electron microscopy revealed only the plastically deformed region occurring at the depth up to ca. 50 ?m and cracks at the depth less than 30 ?m. The comparison with the results obtained for the AK12 alloy containing almost a twice higher amount of silicon demonstrates the influence of the hard silicon rich particles on the total depth of the subsurface zone. A higher amount of hard particle prevents to some extend the propagation of defects inside the material.

Dryzek, E.; Dryzek, J.

2006-11-01

339

Abrasive wear of alumina fibre-reinforced aluminium  

NASA Astrophysics Data System (ADS)

The friction and abrasive wear behaviour of an Al-Si1MgMn aluminium alloy reinforced with 10, 15 and 30 vol.% of alumina fibers has been evaluated. The influence of fiber content, matrix hardness, applied load as well as the hardness and size of the abrasive grits was investigated. The tests were performed with a pin-on-drum two-body abrasion apparatus. The wear mechanisms were studied using scanning electron microscopy. It is shown that fiber reinforcement increases the wear resistance in milder abrasive situations, i.e. small and soft abrasives and low loads. However, in tougher abrasive situations, meaning coarse and hard abrasives and high loads, the wear resistance of the composites is equal to or, in some cases, even lower than that of the unreinforced material. It is also shown that the coefficient of friction decreases with increasing fiber content and matrix hardness of the composites.

Axen, N.; Alahelisten, A.; Jacobson, S.

1994-04-01

340

Neutron irradiation influence on magnesium aluminium spinel inversion  

NASA Astrophysics Data System (ADS)

Grown by the Verneuil method MgO/.nAl2O3 single crystals and natural spinel crystal have been studied using X-ray diffraction and photoluminescence spectra. The fast neutron irradiation of magnesium aluminium spinel leads to the lattice parameter decrease. The bond lengths of Mg-O and Al-O vary with the u-parameter and the lattice parameter. On the other hand, the bond lengths are related with the inversion parameter. Using changes of the lattice parameter during irradiation we have calculated the inversion parameter, which is 15-20%. In the luminescence spectra, the fast neutron radiation (fluence 1016 cm-2) produces an increase in the intensity ratio of the N- to R-lines by 5-20%. Taking into account that intensity of the N-lines is closely associated with the inversion parameter, it is possible to state that the neutron irradiation causes the increasing of the spinel inversion.

Skvortsova, V.; Mironova-Ulmane, N.; Ulmanis, U.

2002-05-01

341

Nanoporous structures from anodisation of non-planar aluminium surfaces  

NASA Astrophysics Data System (ADS)

We report about a novel combination of two etching techniques for generating nanostructures, which individually are well established: (i) metal tip etching in NaOH, as e.g. used for STM or atom probe tip making, and (ii) anodic oxidation of aluminium for the generation of self-organised ordered pores. The non-planar geometry in both these etching processes allowed us to follow the electric field mediated orientation of pattern growth observable in the SEM. Surface-near porosity is found from both etching processes, however only anodisation leads to continued growth of deep channel-like pores. FIB cross-sections of the cone and tip regions are found suitable to study the oxide-metal interface distribution and their dependence with anodisation time and current, even grain boundaries between the two opposite regions of deep pores are observed.

Mu, X.; Peng, Y.; Gnanavel, T.; Inkson, B. J.; Möbus, G.

2010-07-01

342

Frictional conditions between alloy AA6060 aluminium and tool steel  

NASA Astrophysics Data System (ADS)

The frictional conditions in the new process of screw extrusion of aluminium have been investigated. The contact behaviour between the aluminum alloy and the tool steel in the extruder is vital for understanding the extrusion process. Using a compressive-rotational method for frictional measurements the conditions for unlubricated sticking friction between aluminum alloy AA6060 and tool steel at different combinations of temperatures and pressures have been investigated. In this method the samples in the form of disks are put under hydrostatic pressure while simultaneously being rotated at one end. Pins made from contrast material have been inserted into the samples to measure the deformation introduced. This approach along with 3D simulations form a method for determining the frictional conditions. The paper describes the test method and the results. It was found that the necessary pressure for sticking to occur between the aluminum AA6060 and the different parts of the extruder is heavily influenced by the temperature.

Widerøe, Fredrik; Welo, Torgeir

2011-05-01

343

Materials Science Constraints on the Development of Aluminium Reduction Cells  

NASA Astrophysics Data System (ADS)

The Hall-Heroult process for the production of Aluminium metal is some 125 years old. The process is energy constrained by the need to shed around half of the (electrical) energy supplied to the cell as waste heat. The molten cryolite electrolyte is sufficiently aggressive that the only reliable method of protecting the side wall of the cell is to maintain a frozen layer of electrolyte at the hot face of the sidewall. Thus the lack of a cryolite resistant sidewall is but one of several materials science constraints which still limit the energy efficiency of the process. An inert anode and non-consumable cathode are also significant challenges which limit cell life and energy efficiency. Thus there are major challenges in both materials development and new conceptual cell designs to improve the efficiency of this process.

Metson, James; McIntosh, Grant; Etzion, Ronny

344

Ultrafine particles at workplaces of a primary aluminium smelter.  

PubMed

The number concentration and size distribution of ultrafine particles in a Søderberg and a prebake potroom of an aluminium primary smelter have been measured using a scanning mobility particle spectrometer. The particle morphology was studied by transmission electron microscopy (TEM). The study shows the existence of elevated number concentrations of ultrafine particles in both potrooms. The main source of these particles is likely to be the process of anode changing. The ultrafine particles were measured directly at the source but could also be identified as episodes of high number concentrations in the general background air. Unlike the larger particles belonging to the 50-100 nm mode, the nanoparticle mode could not be detected in the TEM indicating that they may not be stable under the applied sampling conditions and/or the high vacuum in the instrument. PMID:16395469

Thomassen, Yngvar; Koch, Wolfgang; Dunkhorst, Wilhelm; Ellingsen, Dag G; Skaugset, Nils-Petter; Jordbekken, Lars; Arne Drabløs, Per; Weinbruch, Stephan

2005-12-07

345

Parameter subset selection based damage detection of aluminium frame structure  

NASA Astrophysics Data System (ADS)

A three storey aluminium frame structure was tested in multiple damage cases. All damage scenarios, simulated by the localized stiffness changes, were associated with joint areas of the structure. Further, between damage tests the structure was returned to its healthy reference conditions and was again measured. In this paper, a parameter subset selection methodology is applied to an updated finite element model of the structure, together with a previously demonstrated approach employing concepts of model sensitivity subspace angles, first order model representation and mixed response residuals for damage detection. The objective of this paper is the evaluation of these methods on a real experimental structure with significant complexity, represented by an imprecise reference mathematical model and in the environment with uncertain reference structural state. The questions of symmetry, mixed response residuals and semi-localized parameterization are also addressed in this work.

Titurus, B.; Friswell, M. I.

2011-07-01

346

Frictional conditions between alloy AA6060 aluminium and tool steel  

SciTech Connect

The frictional conditions in the new process of screw extrusion of aluminium have been investigated. The contact behaviour between the aluminum alloy and the tool steel in the extruder is vital for understanding the extrusion process. Using a compressive-rotational method for frictional measurements the conditions for unlubricated sticking friction between aluminum alloy AA6060 and tool steel at different combinations of temperatures and pressures have been investigated. In this method the samples in the form of disks are put under hydrostatic pressure while simultaneously being rotated at one end. Pins made from contrast material have been inserted into the samples to measure the deformation introduced. This approach along with 3D simulations form a method for determining the frictional conditions. The paper describes the test method and the results. It was found that the necessary pressure for sticking to occur between the aluminum AA6060 and the different parts of the extruder is heavily influenced by the temperature.

Wideroee, Fredrik; Welo, Torgeir [Norwegian University of Science and Technology-Dept. of Engineering Design and Materials-Norway (Norway)

2011-05-04

347

Aluminium segregation of TiAl during single crystal growth  

SciTech Connect

{gamma}-TiAl single crystals have been successfully prepared by an induction-heated cold crucible Czochralski technique which offers more flexibility than vertical float zoning. Compositional analysis of the Czochralski grown single crystals indicates a homogeneous composition after initial transition; and the average composition is close to the peritectic composition. However, {gamma}-TiAl single crystals prepared by vertical float zoning show a small aluminium segregation profile along the growth direction; and the average composition of the as-grown crystals is close to that of the starting alloy. Compositional analysis further demonstrated the banded structure with alternative single {gamma}-phase and {alpha}{sub 2} + {gamma} lamellar regions in the vertical float zoned Ti-54 at.% Al.

Bi, Y.J.; Abell, J.S. [Univ. of Birmingham (United Kingdom). School of Metallurgy and Materials

1997-09-15

348

Preparation of functionalized organoaluminiums by direct insertion of aluminium to unsaturated halides  

NASA Astrophysics Data System (ADS)

The preparation of polyfunctional organometallics is important in organic synthesis as these reagents are very popular nucleophiles. The preparation of functionalized aluminium reagents by direct insertion of aluminium powder is in general not possible. Such a reaction would be of special importance owing to the low price of aluminium compared with magnesium (it is half the price), the low toxicity of this metal and the chemoselectivity of the resultant organoaluminium reagents. We have now found that by adding catalytic amounts of selected metallic chlorides (TiCl4, BiCl3, InCl3 or PbCl2) in the presence of LiCl, aluminium powder inserts into various unsaturated iodides and bromides under mild conditions. These resulting new organoaluminium reagents undergo smooth Pd-catalysed cross-coupling and acylation reactions, as well as copper-catalysed allylic substitutions, affording various interesting products for pharmaceutical and material science applications.

Blümke, Tobias; Chen, Yi-Hung; Peng, Zhihua; Knochel, Paul

2010-04-01

349

ASCOR Test: A Simple Automated Method for Stress Corrosion Testing of Aluminium Alloys.  

National Technical Information Service (NTIS)

Alternate immersion stress corrosion testing according to ASTM specification G44 has proven to be representative for aluminium alloys in natural environments resembling the actual environmental conditions for aircraft. A simple automated stress corrosion ...

L. Schra F. F. Groep

1991-01-01

350

Fabrication of Highly Ordered Anodic Aluminium Oxide Templates on Silicon Substrates.  

National Technical Information Service (NTIS)

The controlled fabrication of highly ordered anodic aluminium oxide (AAO) templates of unprecedented pore uniformity directly on Si, enabled by new advances on two fronts -- direct and timed anodisation of a high-purity Al film of unprecedented thickness ...

A. Yin D. Cardimona J. Xu L. Guo M. Tzolov

2007-01-01

351

Comparison of modification with strontium and the refining with antimony in A 356 aluminium alloys.  

National Technical Information Service (NTIS)

Strontium and Antimony treated A356 aluminium alloy samples were metallographically characterized in the as cast and solution and aged conditions. Antimony treated alloy has shown slower spheroidizing kinetics of the Silicon particles during solution trea...

R. Fuoco E. R. Correa A. V.O. Correa M. Bocalini Junior

1992-01-01

352

Electrochemical noise and impedance study of aluminium in weakly acid chloride solution  

Microsoft Academic Search

The electrochemical noise (EN) characteristics of pure aluminium in unbuffered potassium chloride solution and with acetic acid\\/sodium acetate buffer at pH 5.4 and 4.3 have been analysed to throw light on the influence of pH and of the presence of buffer at the aluminium surface on chloride ion-induced corrosion. Comparison has been made with results obtained by electrochemical impedance spectroscopy

Carla Gouveia-Caridade; M. Isabel S. Pereira; Christopher M. A. Brett

2004-01-01

353

Optimisation of the rivet joints of the CFRP composite material and aluminium alloy  

Microsoft Academic Search

Purpose: The project included analysis of strain, cracking, and failure of riveted joints of plate elements made from the carbon-fibre-reinforced plastics (CFRP) and from the 6061 aluminium alloy. Design\\/methodology\\/approach: The modelled static tensile strength test carried out for the plates from CFRP and from the 6061 aluminium alloy joined with the steel rivet. Computer simulation was carried out with IDEAS

W. Hufenbach; L. A. Dobrza?ski; M. Gude; J. Konieczny; A. Czulak

2007-01-01

354

Capacitance–voltage, current–voltage, and thermal stability of copper alloyed with aluminium or magnesium  

Microsoft Academic Search

Copper alloyed with small amounts of aluminium or magnesium has recently been suggested as a promising material for interconnect applications in silicon integrated circuits. This work reports the results of the investigation of the electrical (capacitance–voltage and current–voltage) stability of the metal–oxide–semiconductor capacitor made with copper–0.5 at.% aluminium and copper–2 at.% magnesium as metal, deposited on thermally oxidized silicon substrates.

T Suwwan de Felipe; S. P Murarka; S Bedell; W. A Lanford

1998-01-01

355

Joining of stainless-steel and aluminium materials by friction welding  

Microsoft Academic Search

The joining of dissimilar materials is of great importance in industry. Especially, if it is used as the lightest part of\\u000a the machine parts, materials such as aluminium and magnesium can be joined with different steels. Therefore, in this study,\\u000a austenitic stainless-steel and aluminium materials were welded using the friction welding method. Optimum parameters for joints\\u000a were obtained by using

Mumin Sahin

2009-01-01

356

Quench collection of nano-aluminium agglomerates from combustion of sandwiches and propellants  

Microsoft Academic Search

An experimental investigation has been carried out to measure the size of nano-aluminium agglomerates emerging from the combustion of nano-aluminized sandwiches and composite solid propellants. Nano-aluminium of median size of 50nm produced in-house by the electrical wire explosion method is used in these samples. Propellants with different sizes of coarse and fine ammonium perchlorate are considered. Surface features of sandwiches

K. Jayaraman; S. R. Chakravarthy; R. Sarathi

2011-01-01

357

Defluoridation of Sahara water by small plant electrocoagulation using bipolar aluminium electrodes  

Microsoft Academic Search

The purpose of this paper is to propose an efficient and low cost defluoridation process based on electrocoagulation with aluminium bipolar electrodes. The performance of a pilot scale electrochemical reactor equipped with aluminium bipolar electrodes with an anode active area surface of about 1.6 m2 was studied. The pilot study yielded promising results, suggesting that further in-depth development studies are

N. Mameri; H. Lounici; D. Belhocine; H. Grib; D. L. Piron; Y. Yahiat

2001-01-01

358

Effects of Shielding Gas on Absorption Energy of Nd-YAG Laser for Aluminium Welding  

NASA Astrophysics Data System (ADS)

Aluminium is the one of the most abundant element situated in Earth's crust and using in thousands of industrial applications. In this study spectroscopic analysis for 1mm thick aluminium plates investigated and electron temperatures were calculated with using emission spectra obtained from plasma. The relation between electron temperature and shielding gas pressure, type, pulse energy, beam focus position and flow direction were observed. With using shielding gases Ar, He, N2 at different pressures the bead widths was measured.

Mutlu, M.; Akman, E.; Demir, A.

2007-04-01

359

Physically-based constitutive modelling of residual stress development in welding of aluminium alloy 2024  

Microsoft Academic Search

A finite element model has been developed to predict the evolution of residual stress and distortion which takes into account the history-dependence of the yield stress–temperature response of heat-treatable aluminium alloys during welding. The model was applied to TIG welding of 2024-T3 aluminium alloy, and the residual strain predictions validated using high resolution X-ray synchrotron diffraction. The goal was to

R. V. Preston; H. R.. Shercliff; P. J. Withers; S. Smith

2004-01-01

360

Aluminium Determination in Bottled Mineral Waters by Electrothermal Atomic Absorption Spectrometry  

Microsoft Academic Search

Over one hundred samples of natural mineral waters corresponding to 43 domestic and foreign brands were analyzed for the aluminium content by electrothermal atomic absorption spectrometry. Good reproducibility, sensitivity, and rapidity make the method convenient for routine aluminium determination. The calibration curve was linear from 1.9 to 80 ng\\/ml and the detection limit was 1.9 ng\\/ml (characteristic mass 38 pg

Maria Plessi; Agar Monzani

1995-01-01

361

Measurement of the electrical resistance of aluminium samples in sulphuric acid solutions by optical interferometry techniques  

Microsoft Academic Search

Holographic interferometry was utilized for the first time to measure the electrical resistance of aluminium samples during the initial stage of anodization processes in aqueous solution without any physical contact. The anodization process (oxidation) of the aluminium samples was carried out chemically in different sulpheric acid concentrations (0.5 - 3.125% H2SO4) at room temperature. In the mean time, a method

Khaled Habib

2005-01-01

362

Determining Biogenic Silica in Marine Samples by Tracking Silicate and Aluminium Concentrations in Alkaline Leaching Solutions  

Microsoft Academic Search

This study introduces an alkaline leaching technique for the simultaneous analysis of biogenic silica and aluminium in sediments. Measuring aluminium facilitates the discrimination between silica from the biogenic (BSiO2) and the non-biogenic fraction, because it originates almost solely from the lithogenic phase. The method was tested using fine-grained silicagel, standard clay minerals, artificial sediments, and natural samples ranging from fresh

Erica Koning; Eric Epping; Wim Van Raaphorst

2002-01-01

363

Alterations in lipid composition and neuronal injury in primates following chronic aluminium exposure  

Microsoft Academic Search

The effect of chronic aluminium exposure (25 mg\\/kg b.wt.) was studied on the lipid composition and various membrane-bound\\u000a enzymes in different regions of monkey brain. Aluminium (Al) administration caused a significant decrease in the total lipid,\\u000a glycolipid, and phospholipid content of primate brain. Cholesterol levels and the phospholipid to cholesterol ratio were,\\u000a however, markedly increased as a consequence of Al

Sanjay Sarin; Vandana Gupta; Kiran Dip Gill

1997-01-01

364

Synthesis and characterization of molybdenum aluminide nanoparticles reinforced aluminium matrix composites  

Microsoft Academic Search

Aluminium matrix composites reinforced with molybdenum aluminide nanoparticles were synthesized by ball milling and reactive sintering of the mixture of aluminium and 10wt% hydrated molybdenum oxide powders. Sintering the as milled powder in air below 750°C produced MoAl12 intermetallic compound nanoparticles, at 750°C produced a mixture of MoAl5 and MoAl4 nanoparticles and at 800°C under Argon atmosphere produced predominantly MoAl4

R. Maiti; M. Chakraborty

2008-01-01

365

Highly aluminium doped barium and strontium ferrite nanoparticles prepared by citrate auto-combustion synthesis  

Microsoft Academic Search

Aluminium doped barium and strontium hexaferrite nanoparticles BaAlxFe(12?x)O19 and SrAlxFe(12?x)O19 were synthesised via a sol–gel route using citric acid to complex the ions followed by an auto-combustion reaction. This method shows promise for the synthesis of complex ferrite powders with small particle size. It was found that around half of the iron could be substituted for aluminium in the barium

Neil J.. Shirtcliffe; Simon Thompson; Eoin S. O’Keefe; Steve Appleton; Carole C.. Perry

2007-01-01

366

Formation and characterisation of Ti–Zr based conversion layers on AA6060 aluminium  

Microsoft Academic Search

Formation of a Ti–Zr based conversion layer on AA6060 aluminium has been studied electrochemically and by use of various surface analytical methods. Measurements show that the ?-Al(Fe,Mn)Si particles present in AA6060 are cathodic to the aluminium matrix in a fluorotitanate–zirconate (H2TiF6–H2ZrF6) based solution, and reduction reactions occur predominantly on the particles. The alkaline diffusion layer thus formed causes preferential deposition

O. Lunder; C. Simensen; Y. Yu; K. Nisancioglu

2004-01-01

367

Perforation of AA5083-H116 aluminium plates with conical-nose steel projectiles – Calculations  

Microsoft Academic Search

The use of aluminium alloys in lightweight protective structures is increasing. Even so, the number of experimental and computational investigations that give detailed information on such problems is limited. In an earlier paper by some of the authors, perforation experiments were performed with 15–30mm thick AA5083-H116 aluminium plates and 20mm diameter, 98mm long, HRC 53 conical-nose hardened steel projectiles. In

T. Børvik; M. J. Forrestal; O. S. Hopperstad; T. L. Warren; M. Langseth

2009-01-01

368

Neurotoxic Effects of Aluminium Among Foundry Workers and Alzheimer’s Disease  

Microsoft Academic Search

Background: In a cross-sectional case-control study conducted in northern Italy, 64 former aluminium dust-exposed workers were compared with 32 unexposed controls from other companies matched for age, professional training, economic status, educational and clinical features. The findings lead the authors to suggest a possible role of the inhalation of aluminium dust in pre-clinical mild cognitive disorder which might prelude Alzheimer’s

Salvatore Polizzi; Enrico Pira; Mauro Ferrara; Massimiliano Bugiani; Andrea Papaleo; Roberto Albera; Silvana Palmi

2002-01-01

369

Fatigue Behaviour of Friction Stir Welded 6061-T6 Aluminium Alloy  

Microsoft Academic Search

Friction stir welding (FSW) is a recently developed solid state welding method, and now being used increasingly for joining\\u000a aluminium alloys. However, the fatigue behaviour of FSW joints with relatively complicated microstructure is still unclear.\\u000a In this study, fatigue behaviour of FSW joints of 6061-T6 aluminium alloy was investigated. The 6061-T6 plates were joined\\u000a with welding speeds of 100 and

Yoshihiko Uematsu; Keiro Tokaji; Yasunari Tozaki; Hideaki Shibata

370

Chip formation in the machining of SiC-particle-reinforced aluminium-matrix composites  

Microsoft Academic Search

As a consequence of the widening range of applications of metal-matrix composites (MMCs), the machining of these materials has become a very important subject for research. Aluminium-matrix composites are widely used for their favourable specific strength\\/stiffness and corrosion resistance properties. This paper describes a study of chip formation during the machining of a DURALCAN® aluminium-matrix composite (A359\\/SiC\\/20p). For good machinability,

J. T. Lin; D. Bhattacharyya; W. G. Ferguson

1998-01-01

371

High-molecular weight styrene-maleic acid copolymers as corrosion inhibitors for aluminium pigments  

Microsoft Academic Search

High-molecular weight styrene-maleic acid copolymers inhibit the corrosion of aluminium pigments in a mixture of water and butyl glycol at a ratio 9:1 at a pH value of 10 very effectively (protection factors up to 99%). This was proved by volumetric measurement of the corrosion product hydrogen. High-molecular weight polyacrylic acids are much less effective corrosion inhibitors for aluminium pigments.

B. Müller; T. Schmelich

1995-01-01

372

Effects of aluminium in the Zn coating on electrode life in welding galvanized steel sheet  

Microsoft Academic Search

The purpose of this study was to investigate effects of aluminium in the Zn coating on electrode life in welding galvanized steel sheet. Three hot?dip galvanized and one electro?galvanized steel sheet types were prepared for this study. Aluminium content in the coatings varied within the range 0.26–0.87 mass% for the three types of hot?dip galvanized sheet.The approach used here included

H. Matsuda; Y. Matsuda; M. Kabasawa

1996-01-01

373

ETAAS determination of aluminium and copper in dialysis concentrates after microcolumn chelating ion-exchange preconcentration  

Microsoft Academic Search

A procedure was developed for the preconcentration and determination of aluminium and copper in dialysis concentrates at\\u000a the ng cm–3 level. The preconcentration was achieved on microcolumns filled with Chelex-100 resin adjusted to a pH of 4.0. Five repetitive\\u000a cycles of the sample through the column ensured a sufficient contact time for quantitative retention of aluminium and copper\\u000a ions. The

Svetlana Kneževi?; R. Mila?i?; Marjan Veber

1998-01-01

374

Aluminium in Lake Cuicocha, Ecuador, an Andean Crater Lake: Filterable, Gelatinous and Microcrystal Al Occurrence  

Microsoft Academic Search

In Lake Cuicocha watershed, a young caldera lake, soils consist of volcanic deposits with a high SiO2 and Al2O3 content; these andisols are in an early stage of development; and in drainage water from the watershed, aluminium concentrations\\u000a reach 15.0 ?mol L?1. Total aluminium concentrations in Lake Cuicocha water raises up to 7.2 ?mol L?1, with nearly 70% occurring as filterable Al at neutral

G. Gunkel; C. Beulker; B. Grupe; U. Gernet; F. Viteri

2011-01-01

375

Unsteady pressure measurement instrumentation using anodized-aluminium PSP applied in a transonic wind tunnel  

Microsoft Academic Search

The objective of this work is to demonstrate the feasibility of pressure measurement instrumentation using anodized-aluminium pressure-sensitive paint (or AA-PSP) for application in unsteady flows. An anodized procedure was applied to an aluminium tape that can be easily placed on a model even when it is mounted in a wind tunnel. The response time of the PSP coating is assessed

Marie-Claire Mérienne; Yves LeSant; Jacques Ancelle; Didier Soulevant

2004-01-01

376

Fatigue properties of friction stir welded particulate reinforced aluminium matrix composites  

Microsoft Academic Search

Few papers have discussed the friction stir welding (FSW) of particulate reinforced aluminium matrix composites and most of them focused on the set-up of the welding process parameters and their effect on microstructure, hardness and tensile behaviour. The aim of this study was to investigate the fatigue resistance of FSW joints on an as-cast particulate reinforced aluminium based composite (AA6061\\/22vol.%\\/Al2O3p).

G. Minak; L. Ceschini; I. Boromei; M. Ponte

2010-01-01

377

Aluminium and Alzheimer's disease: sites of aluminium binding in human neuroblastoma cells determined using 26Al and accelerator mass spectrometry  

NASA Astrophysics Data System (ADS)

The aluminium distribution between the major cell compartments of human neuroblastoma cells grown in culture has been determined using 21Al and accelerator mass spectrometry (AMS). Cells (IMR-32) were grown for eight days in a culture medium containing Al-EDTA (0.2mM) spiked with 26Al, harvested, and fractionated by standard biochemical techniques. 26Al in fractions after ashing to Al2O3 was determined by AMS using the 14UD accelerator at ANU Canberra. The cytoplasmic and nuclear cell compartments appeared to have reached diffusive equilibrium with the culture medium. Whilst 26Al was retained by the nuclear proteins and nuclear sap, 26Al did not appear to bind to the nucleic acids (DNA/RNA).

King, S. J.; Templar, J.; Miller, R. V.; Day, J. P.; Dobson, C. B.; Itzhaki, R. F.; Fifield, L. K.; Allan, G. L.

1994-06-01

378

Nineteen cases of persistent pruritic nodules and contact allergy to aluminium after injection of commonly used aluminium-adsorbed vaccines.  

PubMed

Rare cases of persistent pruritic nodules, sometimes associated with aluminium (Al) allergy, have been reported after the use of several Al adsorbed vaccines. During vaccine trials in the 1990s a high incidence of pruritic nodules (645 cases/76,000 recipients), in 77% associated with Al allergy, was observed after the administration of diphtheria-tetanus / acellular pertussis (DT/aP) vaccines from a single producer. In the present report 19 children with pruritic nodules after vaccination with Al hydroxide-adsorbed DTaP/polio+Hib (Infanrix, Pentavac) are described. The children had intensely itching nodules at the injection site, often aggravated during upper respiratory tract infections, and local skin alterations. So far, the symptoms have persisted for up to 7 years. The median time between vaccination and onset of symptoms was 1 month. 16 children were epicutaneously tested for Al, all with positive reactions indicating delayed hypersensitivity to Al. The condition is not commonly known but is important to recognise, as the child and the family may suffer considerably. Future vaccinations with Al-adsorbed vaccines may cause aggravation of the symptoms and the Al allergy. Al-containing skin products, such as antiperspirants, may cause contact dermatitis. Nodules may be mistaken for tumours. Even though the incidence of itching nodules and Al allergy after administration of Infanrix, Pentavac and other Al-adsorbed vaccines is probably low, research to replace Al adjuvants seems appropriate. We conclude that intensely itching subcutaneous nodules, lasting for many years, and hypersensitivity to aluminium may occur after DTaP/polio+Hib vaccination of infants. PMID:16044278

Bergfors, Elisabet; Björkelund, Cecilia; Trollfors, Birger

2005-07-26

379

Naturally occurring radioactive material from the aluminium industry--a case study: the Egyptian Aluminium Company, Nag Hammady, Egypt.  

PubMed

The activity concentrations and the gamma-absorbed dose rates of the terrestrial naturally occurring radionuclides (226)Ra and (232)Th were determined in samples of bauxite, alumina and aluminium dross tailings industrial waste (used to produce two types of alums) using high purity germanium (HPGe) gamma ray spectrometry. The bauxite and alumina are imported by Egyptalum (The Egyptian Aluminium Company, Nag Hammady, Egypt) from Guinea and India. The activity concentrations in the bauxite range from 29 +/- 1 to 112 +/- 6 Bq kg(-1) for (226)Ra, and 151 +/- 8 to 525 +/- 12 Bq kg(-1) for (232)Th, with mean values of 62 +/- 8 and 378 +/- 50 Bq kg(-1), respectively. With respect to alumina and tail, the mean values are 5.7 +/- 1.1 and 8.4 +/- 0.8 Bq kg(-1) for (226)Ra and 7.2 +/- 1.6 and 10.7 +/- 1.2 Bq kg(-1) for (232)Th. Potassium-40 was not detected in any of the studied samples. The measured activity concentrations of (226)Ra and (232)Th in bauxite are higher than the world average while in alumina and tail they are lower. As a measure of radiation hazard to the occupational workers and members of the public, the Ra equivalent activities and external gamma dose rates due to natural radionuclides at 1 m above the ground surface were calculated. The external gamma-radiation doses received by the Egyptalum workers are 97, 409, 8.5 and 12.7 microSv y(-1) for the Guinean and Indian bauxite, the alumina and tail, respectively, which is well below the recommended allowed dose of 1 mSv y(-1) for non-exposed workers. PMID:17146126

Abbady, Adel G E; El-Arabi, A M

2006-11-20

380

Further evidence of centrophenoxine mediated protection in aluminium exposed rats by biochemical and light microscopy analysis.  

PubMed

The environmental agent aluminium has been intensively investigated in the initiation and progression of various neurological disorders and the role of oxidative stress in these disorders is a widely discussed phenomenon. In this light, the present study is focused on the role of aluminium in mediating oxidative stress, which may help in better understanding its role in neuronal degeneration. Further, we have exploited a known anti-aging drug centrophenoxine to explore its potential in the conditions of metal induced oxidative damage. Aluminium was administered orally at a dose level of 100 mg/kg b.wt./day for a period of 6 weeks followed by a post treatment of centrophenoxine at a dose level of 100 mg/kg b.wt./day for another 6 weeks. Following aluminium exposure, a significant increase in lipid peroxidation levels (estimated by MDA) were observed which was accompanied by a decrease in reduced glutathione content in both cerebrum and cerebellum of rat brain. Post treatment of centrophenoxine significantly reduced the lipid peroxidation levels and also increased the reduced glutathione content in both the regions. Histologically observed marked deteriorations in the organization of various cellular layers in both cerebrum and cerebellum were observed after aluminium administration. Centrophenoxine treated animals showed an appreciable improvement in the histoarchitecture of the cellular layers. Our results indicate that centrophenoxine has an antioxidant potential and should be examined further in aluminium toxic conditions. PMID:17688990

Nehru, Bimla; Bhalla, Punita; Garg, Aarti

2007-06-21

381

Aluminium(III) amidinates formed from reactions of `AlCl' with lithium amidinates.  

PubMed

The disproportionation of AlCl(THF)n (THF is tetrahydrofuran) in the presence of lithium amidinate species gives aluminium(III) amidinate complexes with partial or full chloride substitution. Three aluminium amidinate complexes formed during the reaction between aluminium monochloride and lithium amidinates are presented. The homoleptic complex tris(N,N'-diisopropylbenzimidamido)aluminium(III), [Al(C13H19N2)3] or Al{PhC[N(i-Pr)]2}3, (I), crystallizes from the same solution as the heteroleptic complex chloridobis(N,N'-diisopropylbenzimidamido)aluminium(III), [Al(C13H19N2)2Cl] or Al{PhC[N(i-Pr)]2}2Cl, (II). Both have two crystallographically independent molecules per asymmetric unit (Z' = 2) and (I) shows disorder in four of its N(i-Pr) groups. Changing the ligand substituent to the bulkier cyclohexyl allows the isolation of the partial THF solvate chloridobis(N,N'-dicyclohexylbenzimidamido)aluminium(III) tetrahydrofuran 0.675-solvate, [Al(C19H27N2)2Cl]·0.675C4H8O or Al[PhC(NCy)2]2Cl·0.675THF, (III). Despite having a twofold rotation axis running through its Al and Cl atoms, (III) has a similar molecular structure to that of (II). PMID:24096498

Mayo, Dennis H; Peng, Yang; Zavalij, Peter; Bowen, Kit H; Eichhorn, Bryan W

2013-09-06

382

Does aluminium bind to histidine? An NMR investigation of amyloid ?12 and amyloid ?16 fragments.  

PubMed

Aluminium and zinc are known to be the major triggering agents for aggregation of amyloid peptides leading to plaque formation in Alzheimer's disease. While zinc binding to histidine in A? (amyloid ?) fragments has been implicated as responsible for aggregation, not much information is available on the interaction of aluminium with histidine. In the NMR study of the N-terminal A? fragments, DAEFRHDSGYEV (A?12) and DAEFRHDSGYEVHHQK (A?16) presented here, the interactions of the fragments with aluminium have been investigated. Significant chemical shifts were observed for few residues near the C-terminus when aluminium chloride was titrated with A?12 and A?16 peptides. Surprisingly, it is nonhistidine residues which seem to be involved in aluminium binding. Based on NMR constrained structure obtained by molecular modelling, aluminium-binding pockets in A?12 were around charged residues such as Asp, Glu. The results are discussed in terms of native structure propagation, and the relevance of histidine residues in the sequences for metal-binding interactions. We expect that the study of such short amyloid peptide fragments will not only provide clues for plaque formation in aggregated conditions but also facilitate design of potential drugs for these targets. PMID:23464626

Narayan, Priya; Krishnarjuna, Bankala; Vishwanathan, Vinaya; Jagadeesh Kumar, Dasappa; Babu, Sudhir; Ramanathan, Krishna Venkatachala; Easwaran, Kalpathy Ramaier Katchap; Nagendra, Holenarasipur Gundurao; Raghothama, Srinivasarao

2013-07-01

383

Aluminium in an ocean general circulation model compared with the West Atlantic Geotraces cruises  

NASA Astrophysics Data System (ADS)

A model of aluminium has been developed and implemented in an Ocean General Circulation Model (NEMO-PISCES). In the model, aluminium enters the ocean by means of dust deposition. The internal oceanic processes are described by advection, mixing and reversible scavenging. The model has been evaluated against a number of selected high-quality datasets covering much of the world ocean, especially those from the West Atlantic Geotraces cruises of 2010 and 2011. Generally, the model results are in fair agreement with the observations. However, the model does not describe well the vertical distribution of dissolved Al in the North Atlantic Ocean. The model may require changes in the physical forcing and the vertical dependence of the sinking velocity of biogenic silica to account for other discrepancies. To explore the model behaviour, sensitivity experiments have been performed, in which we changed the key parameters of the scavenging process as well as the input of aluminium into the ocean. This resulted in a better understanding of aluminium in the ocean, and it is now clear which parameter has what effect on the dissolved aluminium distribution and which processes might be missing in the model, among which boundary scavenging and biological incorporation of aluminium into diatoms.

van Hulten, M. M. P.; Sterl, A.; Tagliabue, A.; Dutay, J.-C.; Gehlen, M.; de Baar, H. J. W.; Middag, R.

2013-10-01

384

Determining the aluminium occupancy on the active T-sites in zeolites using X-ray standing waves  

NASA Astrophysics Data System (ADS)

Zeolites are microporous crystalline materials that find wide application in industry, for example, as catalysts and gas separators, and in our daily life, for example, as adsorbents or as ion exchangers in laundry detergents. The tetrahedrally coordinated silicon and aluminium atoms in the zeolite unit cell occupy the so-called crystallographic T-sites. Besides their pore size, the occupation of specific T-sites by the aluminium atoms determines the performance of the zeolites. Despite its importance, the distribution of aluminium over the crystallographic T-sites remains one of the most challenging, unresolved issues in zeolite science. Here, we report how to determine unambiguously and directly the distribution of aluminium in zeolites by means of the X-ray standing wave technique using brilliant, focused X-rays from a third-generation synchrotron source. We report in detail the analysis of the aluminium distribution in scolecite, which demonstrates how the aluminium occupancy in zeolites can systematically be determined.

van Bokhoven, Jeroen A.; Lee, Tien-Lin; Drakopoulos, Michael; Lamberti, Carlo; Thieß, Sebastian; Zegenhagen, Jörg

2008-07-01

385

High-frequency micromechanical resonators from aluminium-carbon nanotube nanolaminates.  

PubMed

At micro- and nanoscales, materials with high Young's moduli and low densities are of great interest for high-frequency micromechanical resonator devices. Incorporating carbon nanotubes (CNTs), with their unmatched properties, has added functionality to many man-made composites. We report on the fabrication of < or = 100-nm-thick laminates by sputter-deposition of aluminium onto a two-dimensional single-walled CNT network. These nanolaminates--composed of Al, its native oxide Al(2)O(3) and CNTs--are fashioned, in a scalable manner, into suspended doubly clamped micromechanical beams. Dynamic flexural measurements show marked increases in resonant frequencies for nanolaminates with Al-CNT laminae. Such increases, further supported by quasi-static flexural measurements, are partly attributable to enhancements in elastic properties arising from the addition of CNTs. As a consequence, these nanolaminate micromechanical resonators show significant suppression of mechanical nonlinearity and enhanced strength, both of which are advantageous for practical applications and analogous to biological nanocomposites, similarly composed of high-aspect-ratio, mechanically superior mineral platelets in a soft protein matrix. PMID:18425133

Bak, Jung Hoon; Kim, Young Duck; Hong, Seung Sae; Lee, Byung Yang; Lee, Seung Ran; Jang, Jae Hyuck; Kim, Miyoung; Char, Kookrin; Hong, Seunghun; Park, Yun Daniel

2008-04-20

386

An aluminium nitride light-emitting diode with a wavelength of 210nanometres  

NASA Astrophysics Data System (ADS)

Compact high-efficiency ultraviolet solid-state light sources-such as light-emitting diodes (LEDs) and laser diodes-are of considerable technological interest as alternatives to large, toxic, low-efficiency gas lasers and mercury lamps. Microelectronic fabrication technologies and the environmental sciences both require light sources with shorter emission wavelengths: the former for improved resolution in photolithography and the latter for sensors that can detect minute hazardous particles. In addition, ultraviolet solid-state light sources are also attracting attention for potential applications in high-density optical data storage, biomedical research, water and air purification, and sterilization. Wide-bandgap materials, such as diamond and III-V nitride semiconductors (GaN, AlGaN and AlN; refs 3-10), are potential materials for ultraviolet LEDs and laser diodes, but suffer from difficulties in controlling electrical conduction. Here we report the successful control of both n-type and p-type doping in aluminium nitride (AlN), which has a very wide direct bandgap of 6eV. This doping strategy allows us to develop an AlN PIN (p-type/intrinsic/n-type) homojunction LED with an emission wavelength of 210nm, which is the shortest reported to date for any kind of LED. The emission is attributed to an exciton transition, and represents an important step towards achieving exciton-related light-emitting devices as well as replacing gas light sources with solid-state light sources.

Taniyasu, Yoshitaka; Kasu, Makoto; Makimoto, Toshiki

2006-05-01

387

Aluminium and fluoride contents of tea, with emphasis on brick tea and their health implications.  

PubMed

Tea plant takes up a large quantity of aluminium (Al) and fluoride (F) from acidic soils. It has been known that fluorosis can be developed for people who consume a large quantity of tea made from brick tea, a low quality tea consisting mainly of old tea leaves in China. In addition, it has been claimed that Alzheimer's disease (AD) is linked with the Al content in the human brain. Therefore, the high Al content in tea, especially brick tea is also a concern. This article reviews the basis background on tea including classification, growth conditions, types of tea leaves and their production, and processing of tea. Special emphasis is made on the transfer of Al and F from soil to tea plant and then to tea liquor. Health implications of drinking a large quantity of tea liquor especially those made from brick tea are discussed. Recommendations are suggested to reduce the uptake of these two elements by tea plant, and lower their contents in tea products. PMID:12505437

Wong, M H; Fung, K F; Carr, H P

2003-01-31

388

Roles of organic acid anion secretion in aluminium tolerance of higher plants.  

PubMed

Approximately 30% of the world's total land area and over 50% of the world's potential arable lands are acidic. Furthermore, the acidity of the soils is gradually increasing as a result of the environmental problems including some farming practices and acid rain. At mildly acidic or neutral soils, aluminium (Al) occurs primarily as insoluble deposits and is essentially biologically inactive. However, in many acidic soils throughout the tropics and subtropics, Al toxicity is a major factor limiting crop productivity. The Al-induced secretion of organic acid (OA) anions, mainly citrate, oxalate, and malate, from roots is the best documented mechanism of Al tolerance in higher plants. Increasing evidence shows that the Al-induced secretion of OA anions may be related to the following several factors, including (a) anion channels or transporters, (b) internal concentrations of OA anions in plant tissues, (d) temperature, (e) root plasma membrane (PM) H(+)-ATPase, (f) magnesium (Mg), and (e) phosphorus (P). Genetically modified plants and cells with higher Al tolerance by overexpressing genes for the secretion and the biosynthesis of OA anions have been obtained. In addition, some aspects needed to be further studied are also discussed. PMID:23509687

Yang, Lin-Tong; Qi, Yi-Ping; Jiang, Huan-Xin; Chen, Li-Song

2012-12-27

389

Ruthenium complexation in an aluminium metal-organic framework and its application in alcohol oxidation catalysis.  

PubMed

A ruthenium trichloride complex has been loaded into an aluminium metal-organic framework (MOF), MOF-253, by post-synthetic modification to give MOF-253-Ru. MOF-253 contains open bipyridine sites that are available to bind with the ruthenium complex. MOF-253-Ru was characterised by elemental analysis, N(2) sorption and X-ray powder diffraction. This is the first time that a Ru complex has been coordinated to a MOF through post-synthetic modification and used as a heterogeneous catalyst. MOF-253-Ru catalysed the oxidation of primary and secondary alcohols, including allylic alcohols, with PhI(OAc)(2) as the oxidant under very mild reaction conditions (ambient temperature to 40 °C). High conversions (up to >99%) were achieved in short reaction times (1-3 h) by using low catalyst loadings (0.5 mol% Ru). In addition, high selectivities (>90%) for aldehydes were obtained at room temperature. MOF-253-Ru can be recycled up to six times with only a moderate decrease in substrate conversion. PMID:23042715

Carson, Fabian; Agrawal, Santosh; Gustafsson, Mikaela; Bartoszewicz, Agnieszka; Moraga, Francisca; Zou, Xiaodong; Martín-Matute, Belén

2012-10-05

390

Aluminium in the South Atlantic: Steady state distribution of a short residence time element  

SciTech Connect

The aluminium concentrations of water samples from 18 hydrographic profiles and 35 surface samples in the South Atlantic were determined on board ship during leg III of the South Atlantic Ventilation Experiment (SAVE). The observed surface water distributions (range 0.5 to 57 nM) are though to arise from the partial dissolution of eolian-transported continental dusts coupled with limited lateral transport by prevailing surface currents. In the deep water the greatest enrichments are observed coincident with the depth of the lower North Atlantic Deep Water. The similarity between the Al:Si ratios in this water mass in both the south and north Atlantic is taken as evidence that no significant Al additions are being made to this water during its transit. The lower Al concentrations observed in the water masses of Antarctic origin ({approximately} 3 nM) are consistent with their formation in areas of limited dust input. The somewhat higher values observed in the Antarctic Bottom Water suggest that the shelf component of this water mass may have elevated Al concentrations.

Measures, C.I.; Edmond, J.M. (Massachusetts Inst. of Tech., Cambridge (United States))

1990-04-15

391

High-frequency micromechanical resonators from aluminium-carbon nanotube nanolaminates  

NASA Astrophysics Data System (ADS)

At micro- and nanoscales, materials with high Young's moduli and low densities are of great interest for high-frequency micromechanical resonator devices. Incorporating carbon nanotubes (CNTs), with their unmatched properties, has added functionality to many man-made composites. We report on the fabrication of <=100-nm-thick laminates by sputter-deposition of aluminium onto a two-dimensional single-walled CNT network. These nanolaminates-composed of Al, its native oxide Al2O3 and CNTs-are fashioned, in a scalable manner, into suspended doubly clamped micromechanical beams. Dynamic flexural measurements show marked increases in resonant frequencies for nanolaminates with Al-CNT laminae. Such increases, further supported by quasi-static flexural measurements, are partly attributable to enhancements in elastic properties arising from the addition of CNTs. As a consequence, these nanolaminate micromechanical resonators show significant suppression of mechanical nonlinearity and enhanced strength, both of which are advantageous for practical applications and analogous to biological nanocomposites, similarly composed of high-aspect-ratio, mechanically superior mineral platelets in a soft protein matrix.

Bak, Jung Hoon; Kim, Young Duck; Hong, Seung Sae; Lee, Byung Yang; Lee, Seung Ran; Jang, Jae Hyuck; Kim, Miyoung; Char, Kookrin; Hong, Seunghun; Park, Yun Daniel

2008-06-01

392

Risk of acute toxicity for fish during aluminium application to hardwater lakes.  

PubMed

To assess the risk of aluminium (Al) toxicity during the restoration of the eutrophic lake Tiefwarensee by hypolimnetic addition of NaAl(OH)(4)-solution (aluminate) the generally limnological monitoring was accompanied by fractionation of Al in water and using Al accumulation on fish gills as bioindicator. The concentration of reactive Al species in the alkaline water (pH 8) peaked at 2mgL(-1) in parts of the anoxic hypolimnion and was 0.088+/-0.053mgL(-1) (n=70) in the epilimnion during the five years of treatment. During an Al treatment cycle in summer 2003, perches showed significant Al accumulation on gills (100microg Al g(-1) dw) whereas roaches, breams and silver carps remained unaffected. Thus, the Al toxicity towards several fish species seems to be low, although the concentration of reactive Al in the lake water increased by a factor of 2. However, high Al toxicity due to lake treatment with aluminate could not be excluded, as high Al-gill concentration was observed. An Al balance two years after the treatment indicates complete export of the added Al into the sediment. PMID:20547414

Wauer, Gerlinde; Teien, Hans-Christian

2010-06-14

393

Microleakage of glass ionomer formulations after erbium:yttrium-aluminium-garnet laser preparation.  

PubMed

The aim of this study was to investigate the microleakage in class V cavities restored with four conventionally setting glass ionomers (CGIs) and one resin-modified glass ionomer (RMGI) following erbium:yttrium-aluminium-garnet (Er:YAG) laser or conventional preparation. Four hundred class V cavities were assigned to four groups: A and B were prepared by an Er:YAG laser; C and D were conventionally prepared. In groups B and D, the surface was additionally conditioned with Ketac conditioner. Each group was divided into five subgroups according to the glass ionomer cement (GIC) used: groups 1 (Ketac Fil), 2 (Ketac Molar), 3 (Ionofil Molar), 4 (Ionofil Molar Quick) and 5 (Photac Fil Quick). After thermocycling, a 2% methylene blue solution was used as dye. Scanning electron microscope (SEM) photographs were taken to show the conditioner's effect. Complete marginal sealing could not be reached. PhotacFil showed less microleakage than the conventionally setting glass ionomer cements (CGICs) investigated. Conditioning laser-prepared cavities did not negatively influence microleakage results except for Ionofil Molar Quick. PMID:18716828

Delmé, Katleen I M; Deman, Peter J; De Bruyne, Mieke A A; Nammour, Samir; De Moor, Roeland J G

2008-08-21

394

The influence of aluminium content to the stacking fault energy in Fe-Mn-Al-C alloy system  

Microsoft Academic Search

Four Fe-30Mn-0.9C-XAl alloys are employed to investigate the influence of aluminium content to the stacking fault energy in Fe-Mn-Al-C alloy system. The range of aluminium content is zero to 8.47 wt%. Based on the thermodynamic model, the stacking fault energy can be obtained through calculation. Increasing the aluminium content will make the stacking fault energy of Fe-30Mn-0.9C based alloys increase

W. S. Yang; C. M. Wan

1990-01-01

395

Friction stir welding of titanium alloy TiAl6V4 to aluminium alloy AA2024-T3  

Microsoft Academic Search

Titanium alloy TiAl6V4 and aluminium alloy 2024-T3 were successfully joined by friction stir welding. Microstructure, hardness and tensile strength of the butt joint were investigated. The weld nugget exhibits a mixture of fine recrystallized grains of aluminium alloy and titanium particles. Hardness profile reveals a sharp decrease at titanium\\/aluminium interface and evidence of microstructural changes due to welding on the

Ulrike Dressler; Gerhard Biallas; Ulises Alfaro Mercado

2009-01-01

396

Effects of Welding Processes and Post-Weld Aging Treatment on Fatigue Behavior of AA2219 Aluminium Alloy Joints  

NASA Astrophysics Data System (ADS)

AA2219 aluminium alloy square butt joints without filler metal addition were fabricated using gas tungsten arc welding (GTAW), electron beam welding (EBW), and friction stir welding (FSW) processes. The fabricated joints were post-weld aged at 175 °C for 12 h. The effect of three welding processes and post-weld aging (PWA) treatment on the fatigue properties is reported. Transverse tensile properties of the welded joints were evaluated. Microstructure analysis was also carried out using optical and electron microscopes. It was found that the post-weld aged FSW joints showed superior fatigue performance compared to EBW and GTAW joints. This was mainly due to the formation of very fine, dynamically recrystallized grains and uniform distribution of fine precipitates in the weld region.

Malarvizhi, S.; Balasubramanian, V.

2011-04-01

397

Damage of Aluminium Matrix Composite reinforced with Iron Oxide (Fe3O4): Experimental and Numerical Study  

NASA Astrophysics Data System (ADS)

The powder metallurgy components are being widely used for sophisticated industrial applications at a very high rate production and low cost. In modern industry, more and more it is imposed to develop new composites, such as high resistant, low density, alternative materials in order to realise multifunctional pieces. For this reason, it is very striking to use reinforced (Fe3O4-iron oxide) aluminium matrix composites in structural applications (automotive, aeronautical, etc.) due to their outstanding stiffness-to-weight and strength-to-weight ratios. These materials show good thermal conductivity and wear resistance and also low thermal expansion, all of which makes them very high multifunctional light weight materials. Additionally, it is very attractive way to add Fe3O4-iron oxide reinforcing for improving the magnetic permeability of this composites and by this way, it can be obtained a good synchronization between thermal and electrical conductivities and magnetic permeability.

Ayari, F.; Katundi, D.; Bayraktar, E.

2011-01-01

398

The effects of magnesium additions on the structure and properties of Al7 Si10 SiC p composites  

Microsoft Academic Search

The additions of magnesium to an aluminium alloy matrix, which contains insufficient magnesium, was found to be essential during the synthesis of composites by the stir-casting technique. Magnesium promotes interfacial wetting between the dispersoid surface and the matrix. Dispersion of SiCp in Al-7 Si-0.3 Mg (356) alloy matrix without agglomeration and rejection was not possible. Hence, the addition of up

K. Sukumaran; S. G. K. Pillai; R. M. Pillai; V. S. Kelukutty; B. C. Pai; K. G. Satyanarayana; K. K. Ravikumar

1995-01-01

399

Effect of aluminium on migratory and invasive properties of MCF-7 human breast cancer cells in culture.  

PubMed

Aluminium (Al) has been measured in human breast tissue, nipple aspirate fluid and breast cyst fluid, and recent studies have shown that at tissue concentrations, aluminium can induce DNA damage and suspension growth in human breast epithelial cells. This paper demonstrates for the first time that exposure to aluminium can also increase migratory and invasive properties of MCF-7 human breast cancer cells. Long-term (32weeks) but not short-term (1week) exposure of MCF-7 cells to 10(-4)M aluminium chloride or 10(-4)M aluminium chlorohydrate increased motility of the cells as measured by live cell imaging (cumulative length moved by individual cells), by a wound healing assay and by migration in real time through 8?m pores of a membrane using xCELLigence technology. Long-term exposure (37weeks) to 10(-4)M aluminium chloride or 10(-4)M aluminium chlorohydrate also increased the ability of MCF-7 cells to invade through a matrigel layer as measured in real time using the xCELLigence system. Although molecular mechanisms remain to be characterized, the ability of aluminium salts to increase migratory and invasive properties of MCF-7 cells suggests that the presence of aluminium in the human breast could influence metastatic processes. This is important because mortality from breast cancer arises mainly from tumour spread rather than from the presence of a primary tumour in the breast. PMID:23896199

Darbre, Philippa D; Bakir, Ayse; Iskakova, Elzira

2013-07-12

400

Determination of aluminium induced metabolic changes in mice liver: A Fourier transform infrared spectroscopy study  

NASA Astrophysics Data System (ADS)

In this study, we made a new approach to evaluate aluminium induced metabolic changes in liver tissue of mice using Fourier transform infrared spectroscopy analysis taking one step further in correlation with strong biochemical evidence. This finding reveals the alterations on the major biochemical constituents, such as lipids, proteins, nucleic acids and glycogen of the liver tissues of mice. The peak area value of amide A significantly decrease from 288.278 ± 3.121 to 189.872 ± 2.012 between control and aluminium treated liver tissue respectively. Amide I and amide II peak area value also decrease from 40.749 ± 2.052 to 21.170 ± 1.311 and 13.167 ± 1.441 to 8.953 ± 0.548 in aluminium treated liver tissue respectively. This result suggests an alteration in the protein profile. The absence of olefinicdbnd CH stretching band and Cdbnd O stretching of triglycerides in aluminium treated liver suggests an altered lipid levels due to aluminium exposure. Significant shift in the peak position of glycogen may be the interruption of aluminium in the calcium metabolism and the reduced level of calcium. The overall findings exhibit that the liver metabolic program is altered through increasing the structural modification in proteins, triglycerides and quantitative alteration in proteins, lipids, and glycogen. All the above mentioned modifications were protected in desferrioxamine treated mice. Histopathological results also revealed impairment of aluminium induced alterations in liver tissue. The results of the FTIR study were found to be in agreement with biochemical studies and which demonstrate FTIR can be used successfully to indicate the molecular level changes.

Sivakumar, S.; Sivasubramanian, J.; Khatiwada, Chandra Prasad; Manivannan, J.; Raja, B.

2013-06-01

401

Determination of aluminium induced metabolic changes in mice liver: a Fourier transform infrared spectroscopy study.  

PubMed

In this study, we made a new approach to evaluate aluminium induced metabolic changes in liver tissue of mice using Fourier transform infrared spectroscopy analysis taking one step further in correlation with strong biochemical evidence. This finding reveals the alterations on the major biochemical constituents, such as lipids, proteins, nucleic acids and glycogen of the liver tissues of mice. The peak area value of amide A significantly decrease from 288.278±3.121 to 189.872±2.012 between control and aluminium treated liver tissue respectively. Amide I and amide II peak area value also decrease from 40.749±2.052 to 21.170±1.311 and 13.167±1.441 to 8.953±0.548 in aluminium treated liver tissue respectively. This result suggests an alteration in the protein profile. The absence of olefinicCH stretching band and CO stretching of triglycerides in aluminium treated liver suggests an altered lipid levels due to aluminium exposure. Significant shift in the peak position of glycogen may be the interruption of aluminium in the calcium metabolism and the reduced level of calcium. The overall findings exhibit that the liver metabolic program is altered through increasing the structural modification in proteins, triglycerides and quantitative alteration in proteins, lipids, and glycogen. All the above mentioned modifications were protected in desferrioxamine treated mice. Histopathological results also revealed impairment of aluminium induced alterations in liver tissue. The results of the FTIR study were found to be in agreement with biochemical studies and which demonstrate FTIR can be used successfully to indicate the molecular level changes. PMID:23571087

Sivakumar, S; Sivasubramanian, J; Khatiwada, Chandra Prasad; Manivannan, J; Raja, B

2013-03-21

402

Studies on aluminium leaching from cookware in tea and coffee and estimation of aluminium content in toothpaste, baking powder and paan masala  

Microsoft Academic Search

Studies were conducted in order to assess the level of aluminium (Al) in samples of Indian tea, coffee, toothpaste, paan masala (mouth freshener) and baking powder. Leaching of Al from cookware while preparing tea and coffee was also studied. Experiments were also conducted to study the sequential leaching of Al from cookware by preparing tea and coffee in the presence

Poonam Rajwanshi; Vibha Singh; M. K. Gupta; Vinita Kumari; Rohit Shrivastav; M. Ramanamurthy; Sahab Dass

1997-01-01

403

Additive usage levels.  

PubMed

With the adoption of the European Parliament and Council Directives on sweeteners, colours and miscellaneous additives the Commission is now embarking on the project of coordinating the activities of the European Union Member States in the collection of the data that are to make up the report on food additive intake requested by the European Parliament. This presentation looks at the inventory of available sources on additive use levels and concludes that for the time being national legislation is still the best source of information considering that the directives have yet to be transposed into national legislation. Furthermore, this presentation covers the correlation of the food categories as found in the additives directives with those used by national consumption surveys and finds that in a number of instances this correlation still leaves a lot to be desired. The intake of additives via food ingestion and the intake of substances which are chemically identical to additives but which occur naturally in fruits and vegetables is found in a number of cases to be higher than the intake of additives added during the manufacture of foodstuffs. While the difficulties are recognized in contributing to the compilation of food additive intake data, industry as a whole, i.e. the food manufacturing and food additive manufacturing industries, are confident that in a concerted effort, use data on food additives by industry can be made available. Lastly, the paper points out that with the transportation of the additives directives into national legislation and the time by which the food industry will be able to make use of the new food legislative environment several years will still go by; food additives use data by the food industry will thus have to be reviewed at the beginning of the next century. PMID:8792135

Langlais, R

404

Additional Reference Information  

Center for Biologics Evaluation and Research (CBER)

... Additional Reference Article Information. Grace Chai, Laura Governale, Patty Greene, Hina Mehta, Vicky Borders-Hemphill, David Money. ... More results from www.fda.gov/advisorycommittees/committeesmeetingmaterials/pediatricadvisorycommittee

405

Food & Color Additive Petitions  

Center for Food Safety and Applied Nutrition (CFSAN)

Resources related to food and color additive petitions, including petitions currently held in abeyance. Quick ... Food. Print; ... More results from www.fda.gov/food/ingredientspackaginglabeling/foodadditivesingredients

406

Vector Addition Model  

NSDL National Science Digital Library

The Vector Addition model allows the user to practice vector addition of two vectors in two dimensions. You are given the magnitude and direction of the two vectors, and your goal is to fill in the nine values in the table (showing the x-component, y-component, and length) of the two vectors, and the resultant vector that is the sum of the first two vectors. The Vector Addition was created using the Easy Java Simulations (EJS) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the ejs_bu_vector_addition.jar file will run the program if Java is installed.

Duffy, Andrew

2010-04-25

407

Aluminium exposure disrupts elemental homeostasis in Caenorhabditis elegans†  

PubMed Central

Aluminium (Al) is highly abundant in the environment and can elicit a variety of toxic responses in biological systems. Here we characterize the effects of Al on Caenorhabditis elegans by identifying phenotypic abnormalities and disruption in whole-body metal homeostasis (metallostasis) following Al exposure in food. Widespread changes to the elemental content of adult nematodes were observed when chronically exposed to Al from the first larval stage (L1). Specifically, we saw increased barium, chromium, copper and iron content, and a reduction in calcium levels. Lifespan was decreased in worms exposed to low levels of Al, but unexpectedly increased when the Al concentration reached higher levels (4.8 mM). This bi-phasic phenotype was only observed when Al exposure occurred during development, as lifespan was unaffected by Al exposure during adulthood. Lower levels of Al slowed C. elegans developmental progression, and reduced hermaphrodite self-fertility and adult body size. Significant developmental delay was observed even when Al exposure was restricted to embryogenesis. Similar changes in Al have been noted in association with Al toxicity in humans and other mammals, suggesting that C. elegans may be of use as a model for understanding the mechanisms of Al toxicity in mammalian systems.

Page, Kathryn E.; White, Keith N.; McCrohan, Catherine R.

2013-01-01

408

Guided wave interaction with aerospace aluminium stringer feet  

NASA Astrophysics Data System (ADS)

Acoustic Emission has shown itself to be a valuable technology for reliably detecting damage initiation and growth in large structures. Monitoring of a structure, throughout its life, is possible with sparse sensor arrays. However aerospace structures can be geometrically complex and contain many structural features, the most common being stringers. Stringers are arranged in a way that they can span the length of the wings or fuselage, separated by less than 200mm in certain cases. Therefore it is almost inevitable that, for any reasonable sensor spacing, acoustic emission events propagating guided waves will interact with multiple stringers. A large aerospace aluminium panel is used to minimise the effects of edge reflections and to allow the two fundamental guided wave modes to separate before reception. It is shown that stringer foot height has a noticeable impact on guided wave propagation, for typical aerospace arrangements. A reduction in transmitted signal amplitude was noted as the stringer thickness was increased. However a local maximum was seen when the stringer foot thickness was equal to that of the plate thickness. This paper discusses quantitative analysis of stringer interaction with the fundamental guided wave modes. The effect of the stringer as a feature has been divided into three main interactions; stringer dimensions, coupling media and riveting. Stringer dimensions and coupling media interactions has been investigated here to quantify their effect on transmission and reflection of the fundamental guided wave modes.

Tiplady, Keith; Drinkwater, Bruce W.; Paget, Christophe

2011-03-01

409

Disturbance of cellular iron uptake and utilisation by aluminium.  

PubMed

Aluminium (Al) affects erythropoiesis but the real mechanism of action is still unknown. Transferrin receptors (TfR) in K562 cells are able to bind Tf, when carrying either iron (Fe) or Al, with similar affinity. Then, the aim of this work was to determine whether Al could interfere with the cellular Fe uptake and utilisation. K562 cells were induced to erythroid differentiation by either haemin (H) or sodium butyrate (B) and cultured with and without Al. The effect of Al on cellular Fe uptake, Fe incorporation to haem and cell differentiation was studied. H- and B-stimulated cells grown in the presence of 10 microM Al showed a reduction in the number of haemoglobinised cells (by 18% and 56%, respectively) and high amounts of Al content. Al(2)Tf inhibited both the (59)Fe cellular uptake and its utilisation for haem synthesis. The removal of Al during the (59)Fe pulse, after a previous incubation with the metal, allowed the cells to acquire Fe quantities in the normal range or even exceeding the amounts incorporated by the respective control cells. However, the Fe incorporated to haem could not reach control values in B-stimulated cells despite enough Fe acquisition was observed after removing Al. Present results suggest that Al might exert either reversible or irreversible effects on the haemoglobin synthesis depending on cellular conditions. PMID:11709209

Pérez, G; Garbossa, G; Di Risio, C; Vittori, D; Nesse, A

2001-11-01

410

Ultrasonic Rayleigh Wave Enhancements from Angled Defects in Aluminium  

NASA Astrophysics Data System (ADS)

Non-linear enhancements of ultrasonic surface wave amplitude and frequency have been observed when an incident wave interacts with a surface defect. Previous measurements of surface wave interactions with defects have considered only those that are inclined normal to the surface. Here, the enhancement effects have been studied in aluminium samples with machined slots of fixed length and of varying angle to the horizontal; the degree of enhancement was studied as a function of defect angle using both a scanning laser source, and a scanning laser detector. An automated scanning system has been developed for use with the detector, an IOS two-wave mixer interferometer, capable of measuring the out-of-plane surface displacement on rough surfaces. B-scans, consisting of many A-scans stacked together, were used to identify wave modes present in the near field, the arrival times of which are dependent on the angle of the defect. The observed enhancement is caused by superposition of the incident Rayleigh wave with reflected and mode converted waves, thereby making it angle dependent.

Clough, A. R.; Dutton, B.; Edwards, R. S.

2011-06-01

411

Aspects of fabrication aluminium matrix heterophase composites by suspension method  

NASA Astrophysics Data System (ADS)

Composites with an aluminium alloy matrix (AlMMC) exhibit several advantageous properties such as good strength, stiffness, low density, resistance and dimensional stability to elevated temperatures, good thermal expansion coefficient and particularly high resistance to friction wear. Therefore such composites are more and more used in modern engineering constructions. Composites reinforced with hard ceramic particles (Al2O3, SiC) are gradually being implemented into production in automotive or aircraft industries. Another application of AlMMC is in the electronics industry, where the dimensional stability and capacity to absorb and remove heat is used in radiators. However the main problems are still: a reduction of production costs, developing methods of composite material tests and final product quality assessment, standardisation, development of recycling and mechanical processing methods. AlMMC production technologies, based on liquid-phase methods, and the shaping of products by casting methods, belong to the cheapest production methods. Application of a suspension method for the production of composites with heterophase reinforcement may turn out to be a new material and technological solution. The article presents the material and technological aspects of the transfer procedures for the production of composite suspensions from laboratory scale to a semi-industrial scale.

Dolata, A. J.; Dyzia, M.

2012-05-01

412

High temperature deformation of friction stir processed 7075 aluminium alloy  

SciTech Connect

The mechanical and microstructural properties of 7075 aluminium alloy resulting from Friction Stir Processing (FSP), into sheets of 7 mm thickness, were analysed in the present study. The sheets were processed perpendicularly to the rolling direction; the tensile mechanical properties were evaluated at room temperature in the transverse and longitudinal directions with respect to the processing one. Tensile tests were also performed at higher temperatures and different strain rates in the nugget zone, in order to analyse the superplastic properties of the recrystallized material and to observe the differences from the parent material as a function of the strong grain refinement due to the Friction Stir Process. The high temperature behaviour of the material was studied, in the parallel direction, by means of tensile tests in the temperature and strain rate ranges of 150-500 deg. C and 10{sup -} {sup 2}-10{sup -} {sup 4} s{sup -} {sup 1} respectively, electron microscopy (FEGSEM) observations were carried out to investigate more closely the fracture surfaces of the specimens tested at different temperatures and strain rates.

Cavaliere, P. [Department of Ingegneria dell'Innovazione, University of Lecce, Via per Arnesano I-73100 Lecce (Italy)]. E-mail: pasquale.cavaliere@unile.it; Squillace, A. [Department of Materials and Production Engineering Faculty, University of Naples Federico II (Italy)

2005-08-15

413

Workplace noise exposure after modernisation of an aluminium processing complex.  

PubMed

The aim of this study was to assess to which extent modernisation of an aluminium production complex reduced occupational noise hazard for jobs with the highest potential of exposure. Periodical measurements of noise level were taken at the same workplaces using the same method, before and after modernisation of all plants. The results were compared with the recommended standard. After modernisation, the noise was significantly reduced in all sections of all plants. The greatest reduction was measured in the foundry. After modernisation, the portion of workplaces with excessive noise level dropped significantly (chisquare=21.315; p<0.0001) from 78.4% to 13%. Noise remained a problem in ingot casting and dross skimming section. In the anode plant, noise remained a problem in the green mill section where noise intensities generated by mills and vibrocompactors varied from 95 dB(A) to 102 dB(A). In the electrolysis plant, the portion of workplaces with extensive noise dropped from 77.8% to 39.3% after modernisation (p=0.0019). Noise remains to be a problem at the anode covering section where levels rise up to 100 dB(A). The modernisation of the factory has considerably reduced the noise level in the working environment of all plants, but it can not be reduced completely. PMID:19789164

Doko-Jelini?, Jagoda; Luki?, Jela; Udovici?, Ruzica; Zuskin, Eugenija; Nola, Iskra Alexandra; Zajec, Zdenko

2009-09-01

414

Well servicing fluid additive  

SciTech Connect

Disclosed is a fluid, pourable well servicing fluid additive comprising a water-soluble polymer, an alkaline earth metal base, and a fibrous material suspended in an oleaginous liquid with a gellant and, optionally, a dispersant therefor. The additive is useful in preparing spud muds, lost circulation pills, and spacer fluids during well servicing operations.

Moity, R.M.

1984-03-27

415

Space shuttle microabrasion foil experiment (MFE): Implications for aluminium oxide sphere contamination of near-earth space  

NASA Astrophysics Data System (ADS)

In the Microabrasion Foil Experiment (MFE) flown onboard Shuttle flight STS-3 as part of the OSS-1 scientific payload, four hypervelocity perforation events were recorded by the capture-cell array. Previous investigations /1/ of hypervelocity craters on Skylab IV windows have suggested the presence in near-Earth orbit of a significant population of man-made debris in the form of aluminium oxide spheres from rocket thruster firings. Cosmic dust investigators on the first LDEF mission (launched in April 1984) have expressed concern over the possibility of `contamination' by these Al2O3 particles. For Al2O3 particles in near-Earth orbit the expected impact velocities are of the order of 7-10 kms-1. At a velocity of 10 kms-1, the three near-marginal MFE events are attributed to particles -2?m in diameter and the largest perforation (23?m diameter) to a particle 4-10?m in diameter. Morphological evidence from the three near-marginal events clearly indicates a low density (1-3 g.cm-3) for the impacting projectile which is not entirely consistent with a density of ?=3.97 g.cm-3 for aluminium oxide. Chemical analysis shows silicon enhancement near all crater rims and also calcium for the larger crater. The flux rate deduced for an incident particle mass >1.8×10-12g is 2.6×10-5 m-2.s-1 corrected for Earth shielding. The interplanetary flux at this mass has been placed at 1.0×10-4 m-2.s-1, and hence if the MFE craters were to be considered caused by aluminium oxide, our `natural' particle flux would be a factor of -4 below the interplanetary figure. Considering the additional effects of gravitational enhancement near the Earth, the data suggests that Al2O3 contamination is not a serious threat to the collection and analysis of at least the smaller craters in 5?m foil.

Carey, W. C.; Dixon, D. G.; McDonnell, J. A. M.

416

The crucial role of mitochondrial regulation in adaptive aluminium resistance in Rhodotorula glutinis.  

PubMed

Rhodotorula glutinis IFO1125 was found to acquire increased aluminium (Al) resistance from 50 microM to more than 5 mM by repetitive culturing with stepwise increases in Al concentration at pH 4.0. To investigate the mechanism underlying this novel phenomenon, wild-type and Al-resistant cells were compared. Neither cell type accumulated the free form of Al (Al(3+)) added to the medium. Transmission electron microscopic analyses revealed a greater number of mitochondria in resistant cells. The formation of small mitochondria with simplified cristae structures was observed in the wild-type strain grown in the presence of Al and in resistant cells grown in the absence of Al. Addition of Al to cells resulted in high mitochondrial membrane potential and concomitant generation of reactive oxygen species (ROS). Exposure to Al also resulted in elevated levels of oxidized proteins and oxidized lipids. Addition of the antioxidants alpha-tocopherol and ascorbic acid alleviated the Al toxicity, suggesting that ROS generation is the main cause of Al toxicity. Differential display analysis indicated upregulation of mitochondrial genes in the resistant cells. Resistant cells were found to have 2.5- to 3-fold more mitochondrial DNA (mtDNA) than the wild-type strain. Analysis of tricarboxylic acid cycle and respiratory-chain enzyme activities in wild-type and resistant cells revealed significantly reduced cytochrome c oxidase activity and resultant high ROS production in the latter cells. Taken together, these data suggest that the adaptive increased resistance to Al stress in resistant cells resulted from an increased number of mitochondria and increased mtDNA content, as a compensatory response to reduced respiratory activity caused by a deficiency in complex IV function. PMID:18957597

Tani, Akio; Inoue, Chiemi; Tanaka, Yoko; Yamamoto, Yoko; Kondo, Hideki; Hiradate, Syuntaro; Kimbara, Kazuhide; Kawai, Fusako

2008-11-01

417

Pulmonary Fibrosis and Encephalopathy Associated with the Inhalation of Aluminium Dust  

PubMed Central

The clinical, radiographic, pathological, and environmental features of a case of extensive aluminium fibrosis of the lungs are reported in a man of 49 years of age who had worked for 13½ years in the ball-mill room of an aluminium powder factory. It is noteworthy that his symptoms were referable to the central nervous system, and that he died from terminal broncho-pneumonia following rapidly progressive encephalopathy, associated with epileptiform attacks. He had no presenting pulmonary symptoms, and ?-ray examination of the chest showed only slight abnormalities. Radiographic examination of the chests of 53 other workers in the same factory, and clinical examination with lung function tests of 23 of them revealed no other definite cases of aluminium fibrosis of the lung, nor any other cases with neurological signs and symptoms. Estimations of the aluminium contents of the body tissues such as the lungs, brain, liver, and bone are also recorded. When compared with normal values, it was found that the lungs and brain contained about 20 times and the liver 122 times more than normal. As a contribution to the study of the aluminium content of normal tissues, and as a control series for the results given by Tipton, Cook, Steiner, Foland, McDaniel, and Fentress (1957), and Tipton, Cook, Foland, Rittner, Hardwick, and McDaniel (1958, 1959), the aluminium content of eight “normal” brains was estimated and in all cases it was found to be less than 0·6 ?g. Al/g. wet weight. The results of a survey of the dust concentrations in the factory are also given. The use of aluminium compounds in the experimental production of epilepsy in primates is reviewed, and it is suggested that the neurological signs and symptoms with epileptiform convulsions which occurred in this case might have been related to aluminium intoxication. We hold the view, however, that the interstitial and nodular fibrosis found in the lungs was undoubtedly associated with the inhalation and retention of aluminium dust. Images

McLaughlin, A. I. G.; Kazantzis, G.; King, E.; Teare, Donald; Porter, R. J.; Owen, R.

1962-01-01

418

Study of solid-solution hardening in binary aluminium-based alloys  

NASA Astrophysics Data System (ADS)

Solid-solution formation in binary aluminium-based alloys is due essentially to the combined effects of the size and valence of solvent and solute atoms, as expected by the four Hume-Rothery rules. The lattice parameter of aluminium in the solid solution of the sputtered Al-Fe films is [Al-a (Å)=4.052-6.6×10-3Y]. The increasing and decreasing evolution of the lattice parameter of copper [Cu-a (Å)=3.612+1.8×10-3Z] and aluminium [Al-a (Å)=4.048-1.6×10-3X] in the sputtered Al-1.8 to 92.5 at. % Cu films is a result of the difference in size between the aluminium and copper atoms. The low solubility of copper in aluminium (<1.8 at % Cu) is due to the valences of solvent and solute atoms in contrast with other sputtered films prepared under similar conditions, such as Al-Mg (20 at. % Mg), Al-Ti (27 at. % Ti), Al-Cr (5at. % Cr) and Al-Fe (5.5 at. % Fe) where the solubility is due to the difference in size.

Draissia, Mohamed; Debili, Mohamed-Yacine

2005-09-01

419

Vector Addition Patterns Model  

NSDL National Science Digital Library

The Vector Addition Patterns model illustrates the tail-to-tip method of adding vectors. The table at the bottom shows the components and lengths of the vectors. You can also rotate the vectors and trace out some interesting patterns. The Vector Addition Patterns model was created using the Easy Java Simulations (EJS) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the ejs_bu_vector_addition_patterns.jar file will run the program if Java is installed.

Duffy, Andrew

2010-05-02

420

Isobaric sections of the aluminium phase field in the Al-Ge phase diagram at high pressures up to 2.6 GPa  

Microsoft Academic Search

The isobaric sections of the aluminium phase field in the Al-Ge system have been obtained experimentally at 0.1 MPa, 2.2 and\\u000a 2.6 GPa. The solidus and solid solubility lines of the aluminium phase were determined by electron probe microanalysis of\\u000a alloys quenched after equilibration at known temperatures and pressures. The aluminium phase field of aluminium was observed\\u000a to expand with

Yoritoshi Minamino; Toshimi Yamane; Hideki Araki; Tomohiko Adachi; Yan-Sheng Kang; Yoshinari Miyamoto; Taira Okamoto

1991-01-01

421

Electrodeposition of aluminium from ionic liquids: Part II - studies on the electrodeposition of aluminum from aluminum chloride (AICl 3) - trimethylphenylammonium chloride (TMPAC) ionic liquids  

Microsoft Academic Search

This work presents the studies of the nucleation processes and surface morphology of aluminium electrodeposits obtained on tungsten (W) and aluminium (Al) electrodes from 2:1 molar ratio aluminium chloride (AlCl3)–trimethylphenylammonium chloride (TMPAC) ionic liquids. The deposition processes of aluminium on both W and Al substrates were controlled by an instantaneous nucleation with diffusion-controlled growth. The number densities of the nuclei

T. Jiang; M. J. Chollier Brym; G. Dubé; A. Lasia; G. M. Brisard

2006-01-01

422

Copper Containing Ballistic Additives.  

National Technical Information Service (NTIS)

In accordance with this invention, it has been found that the addition of certain copper compounds to solid propellant composition can materially increase the burning rate of the propellant grains while simultaneously reducing the pressure exponent in the...

R. C. Corley

1981-01-01

423

Base Blocks Addition  

NSDL National Science Digital Library

This virtual manipulative provides base blocks that consist of individual "units," "longs," "flats," and "blocks" (ten of each set for base 10). They can be used to show place value for numbers and to increase understanding of addition and subtraction.

Manipulatives, National L.

2008-12-10

424

Polyaluminoxanes as Fuel Additives.  

National Technical Information Service (NTIS)

Seven polyaluminoxanes, obtained by the interaction of aluminum isopropylate with various acids, were synthesized and characterized. On the basis of polyaluminoxanes which are soluble in hydrocarbons stable fuel additives were prepared with the help of a ...

I. A. Kholomonov M. M. Alimova P. I. Samin S. G. Arabyan V. V. Sher

1972-01-01

425

Effect of surface treatment and gaseous rust protection paper on the atmospheric corrosion stability of aluminium alloy.  

National Technical Information Service (NTIS)

The experimental results of atmospheric corrosion of 166 aluminium alloy of Al-Mg-Si-Cu system and 167 aluminium alloy of Al-Mg-Si-Cu-Fe-Ni system for different surface treatment and different wrapping papers used are introduced. The results show: 1. The ...

G. Gao

1992-01-01

426

[Demonstration by electron probe microanalysis and by ionic microanalysis, of nuclear localization of aluminium of various cells].  

PubMed

The presence of aluminium (A1) in the nuclei of thyroid cells (Rabbits), liver and skin cells (Frogs) and in the nucleolus of a Radiolarian is described. The possibilities of artifacts with these two histophysical methods are briefly discussed, and biological significance of this nucleic aluminium is evoked. PMID:821647

Truchet, M

1976-05-24

427

MATERIAL AND STRUCTURAL BEHAVIOUR OF MIG BUTT WELDS IN 6000 SERIES ALUMINIUM ALLOY EXTRUSIONS FOR RAIL VEHICLES  

Microsoft Academic Search

The welding of 6000 series aluminium alloys can have potentially adverse effects on the material and structural behaviour of the welded joints. In recent accidents involving welded aluminium rail vehicles, some of the longitudinal welds fractured for some metres beyond the zones of severe damage. MIG welding is the main process employed today in the UK and Europe for joining

W Xu; M F Gittos

428

The influence of nickel–aluminium bronze microstructure and crevice solution on the initiation of crevice corrosion  

Microsoft Academic Search

A new mechanistic model has been established for the chemical and electrochemical mechanisms controlling nickel–aluminium bronze crevice corrosion. The crevice corrosion was initially confined to eutectoid regions with slight attack of the copper rich ?-phase within the ?+?III eutectoid. In the presence of high chloride concentrations, copper and aluminium complexes form and the hydrolysis of these complexes leads to the

J. A. Wharton; K. R. Stokes

2008-01-01

429

Comparison of the promoting effects of gallium and aluminium on the n -butane isomerization actvity of sulfated zirconia  

Microsoft Academic Search

Sulfated zirconia catalysts promoted by gallium or aluminium were prepared and tested for n-butane isomerization. Both elements increase and stabilize the isomerization rate. Characterization results showed that the\\u000a promoting mechanism of gallium was different from that of aluminium.

Chong-Jiang Cao; Xi-Zhi Yu; Chang-Lin Chen; Nan-Ping Xu; Yan-Ru Wang; Chung-Yuan Mou

2004-01-01

430

A low cycle fatigue model of a short-fibre reinforced 6061 aluminium alloy metal matrix composite  

Microsoft Academic Search

A low cycle fatigue model has been developed to predict the fatigue life of both the unreinforced aluminium alloy and the short-fibre reinforced aluminium alloy metal-matrix composites based solely on crack propagation from microstructural features. In this approach a crack is assumed to initiate and grow from a microstructural feature on the first cycle. The model assumes that there is

H.-Z. Ding; H. Biermann; O. Hartmann

2002-01-01

431

Eco-friendly corrosion inhibitors: the inhibitive action of Delonix Regia extract for the corrosion of aluminium in acidic media  

Microsoft Academic Search

Purpose – To investigate the inhibitive effect of Delonix regia extracts to reduce the corrosion rate of aluminium in acidic media. The study was a trial to find a low cost and environmentally safe inhibitor to reduce the corrosion rate of aluminium. Design\\/methodology\\/approach – The inhibition efficiency was evaluated using the hydrogen evolution technique at 30°C. The mechanism of adsorption

O. K. Abiola; N. C. Oforka; E. E. Ebenso; N. M. Nwinuka

2007-01-01

432

Minimum quantity lubrication drilling of aluminium–silicon alloys in water using diamond-like carbon coated drills  

Microsoft Academic Search

The dry drilling of aluminium alloys (without using cutting fluids) is an environmentally friendly machining process but also an exceedingly difficult task due to aluminium's tendency to adhere to the drills made of conventional materials such as the high-speed steel (HSS). Diamond-like carbon (DLC) coatings improve the dry drilling performance due to their adhesion mitigating properties. In this work, improvements

Sukanta Bhowmick; Ahmet T. Alpas

2008-01-01

433

Etude de la complexation des ions aluminium par des molécules organiques: Constantes et stoechiométrie des complexes. Application au traitement de potabilisation des eaux  

Microsoft Academic Search

Aluminium salts are commonly used as reactants for coagulation-flocculation in the treatment of drinking water supplies. Powdered activated carbon (PAC) is also sometimes used to decrease accidental or chronic organic pollution. If organic matter has to be removed, powdered activated carbon and aluminium salts can be used simultaneously. The aluminium salts and natural organic matter such as fulvic acids will

G Cathalifaud; J Ayele; M Mazet

1997-01-01

434

Stimulation of amphibian gastroduodenal bicarbonate secretion by sucralfate and aluminium: role of local prostaglandin metabolism.  

PubMed Central

The present studies were designed to explore the possible mode of protective and ulcer healing actions of sucralfate by examining its effect on gastroduodenal bicarbonate secretion by isolated amphibian mucosa. Luminal sucralfate (0.5 g/l) significantly increased bicarbonate secretion by fundic and antral mucosa without influencing transmucosal potential difference. Significant stimulation of duodenal bicarbonate secretion occurred only at 1.0 g/l without change in potential difference. Aluminium, a component of sucralfate, produced similar increases in bicarbonate secretion, while the sucrose and sulphate components were without effect. Pretreatment of mucosae with the cyclooxygenase inhibitor, indomethacin (10 5M) did not abolish the secretory response to sucralfate or aluminium. The results suggest that stimulation of gastroduodenal bicarbonate secretion, possibly by the aluminium moiety of sucralfate, may play a role in its protective and ulcer healing actions.

Crampton, J R; Gibbons, L C; Rees, W D

1988-01-01

435

Image analysis of atmospheric corrosion of field exposure high strength aluminium alloys  

NASA Astrophysics Data System (ADS)

The corrosion morphology image acquisition system which can be used in the field was established. In Beijing atmospheric corrosion exposure station, the image acquisition system was used to capture the early stage corrosion morphology of five types of high strength aluminium alloy specimens. After the denoise treatment, wavelet-based image analysis method was applied to decompose the improved images and energies of sub-images were extracted as character information. Based on the variation of image energy values, the corrosion degree of aluminium alloy specimens was qualitatively and quantitatively analyzed. The conclusion was basically identical with the result based on the corrosion weight loss. This method is supposed to be effective to analysis and quantify the corrosion damage from image of field exposure aluminium alloy specimens.

Tao, Lei; Song, Shizhe; Zhang, Xiaoyun; Zhang, Zheng; Lu, Feng

2008-08-01

436

A comparison of phosphorus and fluorine containing IL lubricants for steel on aluminium.  

PubMed

Ionic liquids have been shown to be highly effective lubricants for a steel on aluminium system. This work shows that the chemistry of the anion and cation are critical in achieving maximum wear protection. The performance of the ILs containing a diphenylphosphate (DPP) anion all showed low wear, as did some of the tris(pentafluoroethyl)trifluorophosphate (FAP) and bis(trifluoromethanesulfonyl)amide (NTf(2)) anion containing ILs. However, in the case of the FAP and NTf(2) based systems, a cation dependence was observed, with relatively poor wear resistance obtained in the case of an imidazolium FAP and two pyrrolidinium NTf(2) salts, probably due to tribocorrosion caused by the fluorine reaction with the aluminium substrate. The systems exhibiting poor performance generally had a lower viscosity, which also impacts on their tribological properties. Those ILs that exhibited low wear were shown to have formed protective tribofilms on the aluminium alloy surface. PMID:22555280

Somers, Anthony E; Biddulph, Shannon M; Howlett, Patrick C; Sun, Jiazeng; MacFarlane, Douglas R; Forsyth, Maria

2012-05-03

437

Preparation and stabilization of aluminium trifluoroacetate fluoride sols for optical coatings.  

PubMed

For the first time, aluminium fluorides in liquid phase are available for optical applications. By modifying the conditions of the fluorolytic sol-gel synthesis of aluminium fluorides transparent sols with low viscosities were obtained. These sols consist mainly of small oligomeric or cluster units of aluminium fluoride which are not measurable by DLS, WAXS, SAXS and show unusual narrow signals in solid state NMR. Isolated particles with diameters up to five nanometers can be identified by TEM measurements and allow the use of their sols in optical and anti reflecting coatings. The sol particles were modified by trifluoroacetic acid to prevent agglomeration, and as a result, the obtained xerogels can be re-dispersed transparently in organic solvents. PMID:22885847

Fritz, C; Scholz, G; Feist, M; Kemnitz, E

2012-08-10

438

Assessing aluminium toxicity in streams affected by acid mine drainage.  

PubMed

Acid mine drainage (AMD) has degraded water quality and ecology in streams on the Stockton Plateau, the site of New Zealand's largest open-cast coal mining operation. This has previously been attributed largely to the effects of acidity and elevated aluminium (Al) concentrations. However, the toxicity of dissolved Al is dependent on speciation, which is influenced by pH which affects Al hydrolysis, as well as the concentrations of organic carbon and sulphate which complex Al. Methods for the assessment of the toxic fraction of Al, by chemical analysis and geochemical modelling, have been investigated in selected streams on the Stockton Plateau, where dissolved Al concentrations ranged from 0.034 to 27 mg L(-1). Modelling using PHREEQC indicated that between 0.2 and 85% of the dissolved Al was present as the free ion Al(3+), the most toxic Al species, which dominated in waters of pH = 3.8-4.8. Al-sulphate complexation reduced the Al(3+) concentration at lower pH, while Al-organic and -hydroxide complexes dominated at higher pH. Macroinvertebrate richness in the streams identified an Al(3+) 'threshold' of approximately 0.42 mg/L, above which taxa declined rapidly. Colorimetric 'Aluminon' analysis on unpreserved, unfiltered waters provided a better estimation of Al(3+) concentrations than inductively couple plasma-mass spectrometry (ICP-MS) on filtered, acidified waters. The Aluminon method does not react with particulate Al or strong Al complexes, often registering as little as 53% of the dissolved Al concentration determined by ICP-MS. PMID:23579831

Waters, A S; Webster-Brown, J G

2013-01-01

439

Accumulation of aluminium in lamellar bone after implantation of titanium plates, Ti-6Al-4V screws, hydroxyapatite granules.  

PubMed

Titanium plates, Ti6Al4V screws and surrounding tissues, and biopsies of hydroxyapatite (Osprovit) grafts of maxillary sinus lifting were investigated to evaluate the release and accumulation of ions. Optical microscopy, SEM and X-ray microanalysis were carried out to evaluate the plates and screws removed from patients presenting inflammation and biopsies. Ions release from metallic appliances or leaching from granules towards soft tissues was observed. An accumulation of aluminium but not titanium was found in soft tissues. A peculiar accumulation of aluminium in the dense lamella of newly formed bone was recorded. The results seem to indicate that biological perturbations may be related to aluminium release from the tested biomaterials. The aluminium content of these biomaterials, its diffusion and accumulation are discussed. Further studies on ion release from biomaterials and aluminium fate in skeletal tissues are suggested. PMID:15020159

Zaffe, Davide; Bertoldi, Carlo; Consolo, Ugo

2004-08-01

440

Additives in plastics.  

PubMed Central

The polymers used in plastics are generally harmless. However, they are rarely used in pure form. In almost all commercial plastics, they are "compounded" with monomeric ingredients to improve their processing and end-use performance. In order of total volume used, these monomeric additives may be classified as follows: reinforcing fibers, fillers, and coupling agents; plasticizers; colorants; stabilizers (halogen stabilizers, antioxidants, ultraviolet absorbers, and biological preservatives); processing aids (lubricants, others, and flow controls); flame retardants, peroxides; and antistats. Some information is already available, and much more is needed, on potential toxicity and safe handling of these additives during processing and manufacture of plastics products.

Deanin, R D

1975-01-01

441

Effect of aluminium doping and annealing on structural and optical properties of cerium oxide nanocrystals  

NASA Astrophysics Data System (ADS)

Nanocrystalline fluorite-like structures of Ce1-xAlxO2-? compounds were prepared by the chemical precipitation method using cerium chloride and aluminium chloride as precursors. The prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and diffuse reflectance spectroscopy (DRS). The effects of aluminium doping concentration and annealing on particle size, lattice parameter and band gap energies were investigated. The particle size of Al-doped CeO2 samples were found to decrease with Al concentration and it increases from 6 to 20 nm as annealing temperature increases to 900 °C.

Dhannia, T.; Jayalekshmi, S.; Santhosh Kumar, M. C.; Prasada Rao, T.; Chandra Bose, A.

2009-11-01

442

PIXE analysis for the study of toxic effects of aluminium in vines  

NASA Astrophysics Data System (ADS)

Elemental concentrations of Mg, A1, Si, P, S, Cl, K and Ca were determined by PIXE in various parts of grape vines grown in a Hoagland water culture with and without added aluminium. The presence of Al enhanced the uptake of P, S and K in leaves and stems, but depressed Mg and Ca. In the roots the Al concentration was very high, while that of Mg was reduced compared to the control samples. The toxic effects of aluminium produced symptoms reminiscent of calcium deficiency.

Meyer, B. R.; Le Roux, E.; Renan, M. J.; Peisach, M.

1984-04-01

443

Exposure to metalworking fluids and respiratory and dermatological complaints in a secondary aluminium plant  

Microsoft Academic Search

Objective  Metal working fluids (MWF) are used during the machining or treatment of metal components as aluminium. The study of adverse\\u000a health effects of exposure to MWF is very important because the potentially exposed population is large. In this study, we\\u000a evaluated 31 workers of three departments (Extrusion, Hot and Cold Rolling Mill) in a secondary aluminium plant.\\u000a \\u000a \\u000a \\u000a Methods  We combined exposure

L. Godderis; T. Deschuyffeleer; H. Roelandt; H. Veulemans; G. Moens

2008-01-01

444

Microstructural analysis of titanium aluminide formed in situ in an aluminium matrix composite  

NASA Astrophysics Data System (ADS)

Titanium aluminide formed in an aluminium matrix composite in situ by hot pressing of titanium and aluminium powders mixture and then annealing was characterized using SEM and TEM methods. It was shown that the original titanium powder was transformed into the intermetallics during the solid state process. Two mechanisms of titanium powder transformation were found, namely diffusion growth and self-propagating high-temperature synthesis (SHS). We describe the morphology of the very fine Al3Ti particles formed during SHS. SHS process does not guarantee a clean interface, with oxygen being identified at some sites on the particle-matrix interface.

Olszówka-Myalska, A.; Maziarz, W.

2010-02-01

445

The genotoxic, hepatotoxic, nephrotoxic, haematotoxic and histopathological effects in rats after aluminium chronic intoxication.  

PubMed

Aluminium (Al) is used in water purification and is also present in several manufactured foods and medicines. Al is known to induce a broad range of physiological, biochemical and behavioural dysfunctions in laboratory animals and humans. This investigation was carried out to investigate the effects of subchronic exposure to Al (as AlCl3) in rats. Sprague-Dawley rats were randomly separated into two groups. Group 1 rats treated with sodium chloride served as the control, group 2 rats were treated with Al (as AlCl3, 5 mg/kg body weight) intraperitonally for 10 weeks. Animals were killed and blood samples were analyzed for blood serum alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) enzyme activities and creatinine, urea (U) and uric acid (UA) levels for evaluating hepatotoxicity and nephrotoxicity. Blood parameters including red blood cells (RBCs), haemoglobin (Hb) concentration, haematocrit (Ht), platelets (PLTs) and white blood cells (WBCs) were compared between control and experimental group to assess haematoxicity. In order to determine the genotoxicity, the number of micronucleated hepatocytes (MNHEPs) was counted in isolated hepatocytes. In addition, histological alterations in liver and kidney samples were investigated. After exposure with Al, the enzymatic activities of ALP, AST, ALT and LDH, and the levels of U and UA significantly increased. RBC, WBC, PLT, Hb and Ht revealed significant decreases in experimental group compared to the control. AlCl3 caused a significant increase in MNHEPs. Furthermore, severe pathological damages were established in both liver and kidney samples. Subchronic exposure to low doses of Al can produce serious dysfunctions in rat blood, liver and kidney, and exposure to this metal can result in greater damages. PMID:22421584

Geyikoglu, Fatime; Türkez, Hasan; Bakir, Tülay Ozhan; Cicek, Mustafa

2012-03-15

446

Impact of aluminium, fluoride and fluoroaluminate complex on ATPase activity of Nostoc linckia and Chlorella vulgaris.  

PubMed

This study demonstrates a pH-dependent inhibition of Mg(2+)- and Ca(2+)-ATPase activities of Nostoc linckia and Chlorella vulgaris exposed to AlCl3, AlF3, NaF and AlCl3+NaF together. AlF3 and the combination of AlCl3+NaF were more inhibitory to both the enzymes as compared with AlCl3 and NaF. Toxicity of the test compounds increased with increasing acidity. Interaction of AlCl3+NaF was additive on N. linckia and C. vulgaris, respectively, at pH 7.5 and 6.8, and synergistic at pH 6.0 and 4.5. In the presence of 60 and 100 microM PO4(3-) an increased NaF concentration (in the AlCl3+NaF combination) was required to produce the same degree of inhibition in ATP synthesis and ATPase activity. Toxicity of fluoroaluminate was reduced in the presence of EDTA and citrate. Except for beryllium to some extent, combinations of cadmium, cobalt, iron, manganese, tin and zinc with fluoride were not as effective as aluminium in inhibiting the ATPase activity. The presence of a 100 kDa protein band in SDS-PAGE of both control as well as AlCl3+NaF-treated samples suggested that AlF4- inhibits the ATPase activity by acting as a functional barrier without affecting the structure of the enzyme. PMID:8696079

Husaini, Y; Rai, L C; Mallick, N

1996-07-01

447

Flow injection determination of aluminium by spectrofluorimetric detection after complexation with N-o-vanillidine-2-amino-p-cresol: the application to natural waters.  

PubMed

An on-line flow injection spectrofluorimetric method for the direct determination of aluminium in water samples is described. The method is based on the reaction of aluminium with N-o-vanillidine-2-amino-p-cresol (OVAC) in acidic medium at pH 4.0 to form a water-soluble complex. The excitation and emission wavelengths were 423.0 and 553.0nm, respectively, at which the OVAC-Al complex gave the maximum fluorescence intensity at pH 4.0 in a 50% methanol-50% water medium at 50 degrees C. An interference from fluoride ions was minimised by the addition of Be(2+). Other ions were found not to interfere at the concentrations likely to be found in natural waters. The proposed methods were validated in terms of linearity, repeatability, detection limit, accuracy and selectivity. Under these conditions, the calibration was linear up to 1000microgL(-1) (r=0.999). The limit of detection (3sigma) for the determination of Al(III) was 0.057microgL(-1) and the precision for multiple determinations of 3ngmL(-1) Al(III) prepared in ultra-pure water was found to be 0.62% (n=10). The Schiff base ligand could be used to determine ultra-trace aluminium from natural waters. Analysis of environmental certified reference materials showed good agreement with the certified values. The procedure was found to be equally applicable to both freshwater and saline solutions, including seawater. PMID:18298968

Kara, Derya; Fisher, Andrew; Hill, Steve J

2008-01-25

448

Electrophilic addition of astatine  

Microsoft Academic Search

It has been shown for the first time that astatine is capable of undergoing addition reactions to unsaturated hydrocarbons. A new compound of astatine, viz., ethylene astatohydrin, has been obtained, and its retention numbers of squalane, Apiezon, and tricresyl phosphate have been found. The influence of various factors on the formation of ethylene astatohydrin has been studied. It has been

Yu. V. Norseev; L. Vasaros; D. D. Nhan; N. K. Huan

1988-01-01

449

Sixth Stack Addition.  

ERIC Educational Resources Information Center

|Discusses the construction of a high density, mobile shelving storage facility addition to the General Library at the University of Illinois Champaign-Urbana campus. Building criteria, space considerations, and the utilization of mobile storage technology are noted. Illustrative material is provided. (EJS)|

Collier, Martin H.

1982-01-01

450

Additive Pulse Mode Locking.  

National Technical Information Service (NTIS)

A new principle of mode locking is analyzed: additive pulse mode locking. It is shown to be operative in two-cavity soliton lasers, but it also permits mode locking with fibers in the positive dispersion regime. A simple model is developed that displays t...

E. P. Ippen H. A. Haus L. Y. Liu

1989-01-01

451

Soluble oil additive concentrate  

SciTech Connect

An additive concentrate was proposed which consisted of 1 to 12 parts alkyl aryl sulfonates (mixture of oil-soluble and water-soluble sulfonates) per part of secondary butyl alcohol. This concentrate was to be combined with the appropriate proportions of liquid hydrocarbon and water to form anhydrous and water-containing soluble oils.

Holm, L.W.

1973-10-30

452

Nitriding of Aluminium Alloy in Nitrogen and Nitrogen-Helium Mixture Using 100 Hz-Pulsed DC Glow Discharge  

NASA Astrophysics Data System (ADS)

Nitriding of aluminium alloy (AlFe1.8Zn0.8) in nitrogen and nitrogen-helium mixture was carried out by using 100 Hz-pulsed DC glow discharge. Samples are treated for different durations, namely 4 h, 8 h and 12 h, in nitrogen plasma as well as in a mixture of nitrogen-helium plasma for the same processing duration of 4 h. All nitriding treatments are carried out at an input power of 100 W, filling pressure of 1 mbar and substrates temperature of 250oC. X-ray diffraction (XRD) results show an expansion in lattice spacing and consequently shift of diffraction peaks towards lower angle with the addition of helium in nitrogen plasma. Surface morphology of the treated sample is investigated by scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). Vickers micro-hardness testing results show increases in surface hardness with processing duration as well as with the addition of helium in nitrogen plasmas. This increase of surface hardness may be attributed to the diffusion of nitrogen content in the surface layer generating internal stresses. It is observed that the addition of helium positively affects the nitriding of samples.

Nasrullah, Khan; M. Shoaib, Shah; R., Ahmad

2010-08-01

453

Experimental studies on machining characteristics of hybrid aluminium metal matrix composite and carbon nano tubes added hybrid aluminium metal matrix composite  

Microsoft Academic Search

This paper discusses the comparative study on machining hybrid aluminium metal matrix composites (Al6061-SiC-Al2O3) and carbon nano tubes (CNT) added hybrid MMCs. The ordinary hybrid composites were fabricated using the liquid metallurgy technique by stir casting method under which wt.6% of particulates SiC and Al2O3 were dispersed in the base matrix. The second CNT-hybrid composite is a woven alumina (Al2O3)

T. Sasimurugan; K. Palanikumar

2011-01-01

454

Drilling mud additive  

SciTech Connect

A processor is described for drilling a borehole that encounters a water-sensitive shale, with the borehole being drilled by operating a drilling means, and circulating therein a drilling fluid, when the encountering of borehole instability due to the interaction of the water and water-sensitive shale is at least imminent, circulating as the drilling fluid an aqueous brine solution that contains from about 0.2 to about 2.0 pounds of an additive per barrel. The additive comprises: 27% by weight of a partially hydrolyzed polyacrylate-polyacrylamide copolymer having a molecular weight of at least three million and which is from about 20 to about 50% hydrolyzed; and 70% by weight of potassium chloride.

Halliday, W.S.; Thielen, V.M.

1987-05-12

455

[Biologically active food additives].  

PubMed

More than half out of 40 projects for the medical science development by the year of 2000 have been connected with the bio-active edible additives that are called "the food of XXI century", non-pharmacological means for many diseases. Most of these additives--nutricevtics and parapharmacevtics--are intended for the enrichment of food rations for the sick or healthy people. The ecologicaly safest and most effective are combined domestic adaptogens with immuno-modulating and antioxidating action that give anabolic and stimulating effect,--"leveton", "phytoton" and "adapton". The MKTs-229 tablets are residue discharge means. For atherosclerosis and general adiposis they recommend "tsar tablets" and "aiconol (ikhtien)"--on the base of cod-liver oil or "splat" made out of seaweed (algae). All these preparations have been clinically tested and received hygiene certificates from the Institute of Dietology of the Russian Academy of Medical Science. PMID:9752776

Velichko, M A; Shevchenko, V P

1998-07-01

456

Nutrient addition to enhance biological treatment of greywater.  

PubMed

This study compares the chemical oxygen demand (COD) removal and respiration rates of a microbial population treating real and synthetic greywaters dosed with nutrient supplements. The nutrient composition of the real and synthetic greywaters was analysed and the dosing regime for nitrogen, phosphorus and a range of trace metals planned accordingly. The doses consisted of eight single additives (macronutrients and trace metals) to the control greywater and six trace metal additions to C: N : P balanced greywater. The COD removal for the control real and synthetic greywater in lab-scale activated sludge systems (0.038 and 0.286 kg COD kg MLSS(-1) d(-1), respectively) confirmed nutrient limitation and the poor degree of greywater treatment. Nutrient dosing increased the COD removal rate and oxygen uptake rate in many cases. The greatest stimulation of microbial activity was observed with zinc additions to C: N: P balanced real greywater (1.291 kg COD kg MLSS(-1) d(-1) over 30 times the control). Inhibitory effects to various extents were rare and limited mainly to the additions of metals to synthetic greywater. The dominance of chemicals effects was observed on addition of some micronutrients; notably iron and aluminium, metals on which many coagulants for use in biotreatment of other wastewaters are based. The data indicate that the impact of understanding microbial processes and the nutrients required for wastewater treatment can only serve to optimise process efficiency for the proposed treatment of greywater. PMID:11456170

Jefferson, B; Burgess, J E; Pichon, A; Harkness, J; Judd, S J

2001-08-01

457

Electrophilic addition of astatine  

SciTech Connect

It has been shown for the first time that astatine is capable of undergoing addition reactions to unsaturated hydrocarbons. A new compound of astatine, viz., ethylene astatohydrin, has been obtained, and its retention numbers of squalane, Apiezon, and tricresyl phosphate have been found. The influence of various factors on the formation of ethylene astatohydrin has been studied. It has been concluded on the basis of the results obtained that the univalent cations of astatine in an acidic medium is protonated hypoastatous acid.

Norseev, Yu.V.; Vasaros, L.; Nhan, D.D.; Huan, N.K.

1988-03-01

458

Generalized Additive Models  

Microsoft Academic Search

Likelihood-based regression models such as the normal linear regression model and the linear logistic model, assume a linear (or some other parametric) form for the covariates $X_1, X_2, \\\\cdots, X_p$. We introduce the class of generalized additive models which replaces the linear form $\\\\sum \\\\beta_jX_j$ by a sum of smooth functions $\\\\sum s_j(X_j)$. The $s_j(\\\\cdot)$'s are unspecified functions that are

Trevor Hastie; Robert Tibshirani

1986-01-01

459

The effect of HNO(3), HCl and HBr on the fluorescence of the aluminium complex of 1-(2-pyridylazo)-2-naphthol and an improved fluorometric procedure for determination of aluminium.  

PubMed

The fluorescence of the aluminium complex of 1-(2-pyridylazo)-2-naphthol (PAN) is both stabilized and enhanced by 10(-3)M HNO(3) . HCl or HBr. Other acids tested have no effect. An improved flourometric procedure with a detection limit of 0.001 ppm, increased precision and reduced interferences over the existing Al-PAN method is described. It is satisfactory for the determination of aluminium in bronze when an ion-exchange separation is used, but is not suitable for the determination of aluminium in plants. The acidified Al-PAN is unsuitable for the determination of nickel(II) and fluoride by fluorescence quenching. PMID:18961432

Haddad, P R; Alexander, P W; Smythe, L E

1974-02-01

460

The Effect of Orientation on the Spall Strength of the Aluminium Alloy 7010-T6  

Microsoft Academic Search

Many polycrystalline alloys experience a pronounced anisotropy in their mechanical properties. This can operate on three levels, these being at the unit cell, the microstructural level (due to preferred orientation of the grain structure) or the meso-scale due to either phase distribution or grain morphology. It is this latter feature in the aluminium alloy AA 7010 that has been chosen

M. R. Edwards; N. K. Bourne; J. C. F. Millett

2002-01-01

461

Effect of Abrasive Blasting on the Fatigue and Corrosion of an Aluminium-Copper Alloy.  

National Technical Information Service (NTIS)

Rotating bending fatigue tests have established that glass bead and alumina grit blasting have only a slight effect on the fatigue properties of 2014-T6 aluminium alloy. Exposure to salt fog for 8 hours or alternate immersion in 3 1/2% salt solution for 3...

C. J. E. Smith M. A. H. Hewins

1984-01-01

462

Analysis of electrochemical noise obtained from pure aluminium in neutral chloride and alkaline solutions  

Microsoft Academic Search

The present work involves the analysis of electrochemical noise obtained from pure aluminium during breakdown of the oxide film in aqueous neutral chloride solution and hydrogen evolution in alkaline solution. Since the noise data involve information on such stochastic processes as uniform corrosion, breakdown of the oxide film and hydrogen evolution, they were analysed based upon a stochastic theory: the

Kyung-Hwan Na; Su-Il Pyun; Hong-Pyo Kim

2007-01-01

463

Modelling the environmental impact of an aluminium pressure die casting plant and options for control  

Microsoft Academic Search

This study describes a model (MIKADO) to analyse options to reduce the environmental impact of aluminium die casting. This model will take a company perspective, so that it can be used as a decision-support tool for the environmental management of a plant. MIKADO can be used to perform scenario analyses to analyse the impact on the environment of different strategies,

Belmira Neto; Carolien Kroeze; Leen Hordijk; Carlos Costa

2008-01-01

464

Tailored aluminium oxide layers by bipolar current adjustment in the Plasma Electrolytic Oxidation (PEO) process  

Microsoft Academic Search

The plasma electrolytic oxidation process of aluminium alloys is investigated for two different current waveforms. It is shown that particular conditions may be established which strongly reduce the arcing that usually cause detrimental defects in the oxide layer for treatment time greater than typically 40–50 min. This results in a “softer” process. As a consequence thick homogenous layers may be grown

F. Jaspard-Mécuson; T. Czerwiec; G. Henrion; T. Belmonte; L. Dujardin; A. Viola; J. Beauvir

2007-01-01

465

Phase formation in ceramic coatings during plasma electrolytic oxidation of aluminium alloys  

Microsoft Academic Search

Phase formation in oxide ceramic coatings on aluminium alloys during plasma electrolytical oxidising has been studied. The theoretical interpretation was based on a model that considers two mechanisms of oxide formation: electrochemical surface oxidation and plasma chemical oxide synthesis in the discharge channels. Thermodynamic calculations were carried out for both the formation of reaction products, as well as heating and

Aleksey L. Yerokhin; Viktor V. Lyubimov; Roman V. Ashitkov

1998-01-01

466

Investigation of the mechanism of plasma electrolytic oxidation of aluminium using 18O tracer  

Microsoft Academic Search

18O is used as a tracer to investigate the mechanism of plasma electrolytic oxidation of aluminium under AC conditions, with distributions of 18O species in the coatings determined by imaging SIMS. The transport of the oxygen species to the inner part of the coating occur through short-circuit paths, leading to formation of fresh alumina within the coating material near to

E. Matykina; R. Arrabal; D. J. Scurr; A. Baron; P. Skeldon; G. E. Thompson

2010-01-01

467

Anodic processes in plasma electrolytic oxidation of aluminium in alkaline solutions  

Microsoft Academic Search

In this paper, basic electrochemical processes (such as oxide film growth, anodic dissolution and oxygen liberation) on an aluminium anode in a model alkaline solution are considered under conditions of galvanostatic DC plasma electrolytic oxidation (PEO). The experiments performed include: (i) recording and analysis of the main electrical characteristics of the process; (ii) determination of the oxide layer thickness; (iii)

L. O Snizhko; A. L Yerokhin; A Pilkington; N. L Gurevina; D. O Misnyankin; A Leyland; A Matthews

2004-01-01

468

The thermal conductivity of plasma electrolytic oxide coatings on aluminium and magnesium  

Microsoft Academic Search

Plasma electrolytic oxide coatings have been produced on both aluminium and magnesium substrates. Their microstructures have been studied and deductions made about formation conditions. The thermal conductivities of the coatings have been measured using a simple steady state method. The values obtained are relatively low (?1 W m?1 K?1). This is explained in terms of the microstructure, which exhibits an

J. A. Curran; T. W. Clyne

2005-01-01

469

Comparative Study of 3D Printing Technologies for Rapid Casting of Aluminium Alloy  

Microsoft Academic Search

The purpose of this study is to compare the efficacy of two rapid casting technologies, namely, ZCast process and investment casting based on 3D printing technique of rapid prototyping for casting of aluminium alloy. A standard procedure has been premeditated starting from the identification and design of benchmark. The concept was presented in physical form by producing prototypes to assess

Simranpreet Singh Gill; Munish Kaplas

2009-01-01

470

Angular distributions of sputtered particles from lithium-implanted aluminium and copper crystals  

Microsoft Academic Search

The anisotropy of angular distributions of sputtered ions from lithium-implanted aluminium and copper single crystals, measured by SIMS analysis, have been used to obtain information about the microstructure of the implanted layers. Sputtered Al+ distributions from the {111} surface show three-fold symmetry with maximum intensity near the and directions respectively, while Li+ distributions show maximum intensity only in the directions.

A. Johansen; E. Johnson; L. Sarholt-Kristensen; S. Steenstrup; H. H. Andersen; V. M. Buhanov; V. S. Chernysh; I. N. Ivanov; K. F. Minnebaev

1991-01-01

471

[Cell nucleus intervention in aluminium concentration by the rat liver cells. Experimental study].  

PubMed

Intravenous injections of Al gluconate enhances immediately the aluminium content of the Rat liver. The cell nuclei are mainly involved in Al accumulation which still remains 10 min. After injection. This experimental model of Al overload is of great potential interest to study Al-nucleic acid interactions. PMID:3113686

Truchet, M; Jeantet, A Y; Petter, C

1987-01-01

472

Design of mechanical clinching tools for joining of aluminium alloy sheets  

Microsoft Academic Search

The purpose of this study is to propose the design method of mechanical clinching tools, which is used to join aluminium alloy sheets in automobiles. Based on the analytical model used to predict the strength of the mechanical clinched joint, the design method of clinching tools that can satisfy the required joint strength is proposed. The analytical model has been

Chan-Joo Lee; Jae-Young Kim; Sang-Kon Lee; Dae-Cheol Ko; Byung-Min Kim

2010-01-01

473

Carbon footprint comparison of sign substrate made from recycled e-waste plastic versus aluminium  

Microsoft Academic Search

Two types of sign substrate material used for road signs and road safety markers, one constructed of reclaimed e-waste plastic and the other of the most commonly used aluminium, are compared in the context of life cycle assessment methodology. This paper also compares the different types of tools available, and determines a suitable tool for use in calculating the carbon

Honglei Wang; Elizabeth K. Walker; Alex Abadi; Guanghong Duan; Hong-chao Zhang

2011-01-01

474

Carbon footprint comparison of sign substrate made from recycled e-waste plastic versus aluminium  

Microsoft Academic Search

Two types of sign substrate material used for road signs and road safety markers, one constructed of reclaimed e-waste plastic and the other of the most commonly used aluminium, are compared in the context of life cycle assessment methodology. This paper also compares the different types of tools available, and determines a suitable tool for use in calculating the carbon

Honglei Wang; Elizabeth K. Walker; Alex Abadi; Guanghong Duan; Hong-chao Zhang

2012-01-01

475

Do aluminium and\\/or glutamate induce Alz-50 reactivity? A light microscopic immunohistochemical study  

Microsoft Academic Search

Alzheimer's disease is thought to be characterized by conformational and phosphorylation changes in tau protein, leading to the formation of aggregations of paired helical filaments within neurons. Potential agents for inducing conformational changes in tau, namely aluminium and glutamate, were investigated in this study. Explant cultures of cortical neurons were established from embryonic day 17 rat fetuses. Cultures were exposed

K. R. Jones; D. E. Oorschot

1998-01-01

476

Applying Research on Creep Constitutive Model of LC4 Aluminium Alloy Based on BC-RBFNN  

Microsoft Academic Search

Creep is an extremely harmful phenomenon which can not be neglected at high temperature. As metal is increasingly used in high temperature structure, investigation on its creep at high temperature has actual significance. In this paper, the creep constitutive relationship of LC4 aluminum alloy under constant stress has been investigated by using creep testing data of LC4 aluminium alloy obtained

Min Yu; Xianghua Peng; Yingshe Luo; Shuiping Yin

2010-01-01

477

Flux Degasser on an Aluminium Bale-out Furnace. A Demonstration at Diecastings Ltd. (Birmingham).  

National Technical Information Service (NTIS)

A new method of cleaning and removing hydrogen from liquid aluminium has been adopted in a sand foundry at Diecastings Ltd. in Birmingham. The new process overcomes problems preventing the fast removal of hydrogen from the molten metal and reduces treatme...

1985-01-01

478

Low-temperature elastic properties of four wrought and annealed aluminium alloys  

Microsoft Academic Search

The elastic properties of four annealed polycrystalline commercial aluminium alloys were studied between 4 and 300 K using a pulse-superposition method. Results are given for longitudinal sound velocity, transverse sound velocity, Young's modulus, shear modulus, bulk modulus (reciprocal compressibility), Poisson's ratio, and elastic Debye temperature. The elastic stiffnesses of the alloys increase 4 to 13% on cooling from room temperature

E. R. Naimon; H. M. Ledbetter; W. F. Weston

1975-01-01

479

Structural durability of cast aluminium gearbox housings of underground railway vehicles under variable amplitude loading  

Microsoft Academic Search

Cast aluminium gearbox housings for railway vehicles are complex shaped components undergoing stochastic stresses during service. Early failures of housings led to broad investigations in order to clarify the causes. By a methodology determining the highly stressed areas, the load spectrum for different operational conditions by service strain measurements, the component related material behaviour, fatigue-life calculations and laboratory proof tests,

C. M. Sonsino

2005-01-01

480

The comparison of galvanostatic and potentiostatic copper powder deposition on platinum and aluminium electrodes  

Microsoft Academic Search

Experiments have been carried out on copper powder electrodeposition by constant overpotential and constant current on aluminium, graphite, platinum and copper electrodes. It is shown that for one and the same quantity of electricity, electrode material, electrode surface area, electrolyte, temperature and time of deposition, different particle size distribution curves, current efficiency and specific energy consumption are obtained in galvanostatic

K. I. Popov; M. G. Pavlovi?; M. D. Maksimovi?; S. S. Krstaji?

1978-01-01

481

Some new aspects of the theory of oxidation and degassing of aluminium-based alloy powders  

Microsoft Academic Search

A study has been performed of the oxidation and degassing processes of aluminium-based alloy powders. Oxidation and hydration of gas-atomized metal powders take place during inflight solidification and cooling to room temperature, during collection and keeping in the powder collection box and during transport and storage before consolidation. Under the atomizing conditions, oxidation cannot be prevented. In contact with humid

L. Kowalski; B. M. Korevaar; J. Duszczyk

1992-01-01

482

Analysis of the effects of controlled shot peening on fatigue damage of high strength aluminium alloys  

Microsoft Academic Search

The use of two micro-mechanical models for notch sensitivity and fatigue life allowed the development of boundary conditions that would evaluate potential life improvement after controlled shot peening (CSP) in high strength aluminium alloys. The boundary conditions describe the state of equal weight between surface roughening and residual stresses and the implication of material and loading parameters. From the boundary

S. Curtis; E. R. de los Rios; C. A. Rodopoulos; A. Levers

2003-01-01

483

Dry Sliding Wear Behaviour of Garnet Particles Reinforced Zinc-Aluminium Alloy Metal Matrix Composites  

Microsoft Academic Search

The present investigation aims to evaluate the wear behaviour of zinc-aluminium (ZA-27) alloy composites reinforced with garnet particles. The liquid metallurgy technique was used to fabricate the composites. The reinforcement content was varied from 0 % to 20 % by weight in steps of 5 %. A pin-on disc wear testing machine was used to evaluate the wear loss of

Mukundadas PRASANNA KUMAR; Kanakuppi SADASHIVAPPA; Gundenahalli Puttappa PRABHUKUMAR; Satyappa BASAVARAJAPPA

2006-01-01

484

Sliding wear behaviour of aluminium-based metal matrix composites produced by a novel liquid route  

Microsoft Academic Search

TiC-reinforced MMCs have been produced in a range of aluminium alloys using a novel casting technique which results in spontaneous incorporation of the particles into the melt and thus strong bonding between the particles and the matrix. The sliding wear behaviour of the extruded composites has been studied as a function of load and particle volume fraction and has been

P. H. Shipway; A. R. Kennedy; A. J. Wilkes

1998-01-01

485

An effective split of flow and die deformation calculations of aluminium extrusion  

Microsoft Academic Search

The purpose of the research project of which this paper is a result is to gain insight in design and control parameters of aluminium extrusion by FE simulations. This is done by means of a thermal FE code based on an ALE algorithm (Dieka). A short overview is given of the material models as well as the FE methods that

H. G. Mooi; P. T. G. Koenis; J. Huétink

1999-01-01

486

Bioleaching of zinc and aluminium from industrial waste sludges by means of Thiobacillus ferrooxidans  

Microsoft Academic Search

Biological solubilisation of heavy metals contained in two different kinds of industrial wastes was performed in batches employing a strain of Thiobacillus ferroxidans. The wastes tested were: a dust coming from the iron-manganese alloy production in an electric furnace (sludge 1) and a sludge coming from a process treatment plant of aluminium anodic oxidation (sludge 2). The experimental results pointed

C Solisio; A Lodi; F Veglio’

2002-01-01

487

Zinc impregnation of the anodic oxidation layer of 1050 and 2024 aluminium alloys  

Microsoft Academic Search

The porous oxide layer obtained by phosphoric anodic oxidation (PAO) of 1050 and 2024T3 aluminium alloys is modified by impregnation with zinc under alternating voltage. The resulting current against applied voltage relationship shows that a threshold voltage is required to deposit the zinc. Beyond a low critical voltage, VcL, zinc electrocrystallization starts near the barrier layer and grows with time

J. P. Dasquet; J. P. Bonino; D. Caillard; R. S. Bes

2000-01-01

488

Mechanical and microstructural investigation of friction spot welded AA6181-T4 aluminium alloy  

Microsoft Academic Search

Friction spot welding (FSpW) is a solid state welding process suitable for spot joining lightweight low melting point materials like aluminium and magnesium alloys. The process is performed by plunging a rotating three-piece tool (clamping ring, sleeve and pin) that creates a connection between sheets in overlap configuration by means of frictional heat and mechanical work. The result is a

T. Rosendo; B. Parra; M. A. D. Tier; A. A. M. da Silva; J. F. dos Santos; T. R. Strohaecker; N. G. Alcântara

2011-01-01

489

Comparison of two different nozzles for laser beam welding of AA5083 aluminium alloy  

Microsoft Academic Search

AA5083 aluminium–magnesium alloy is increasingly used by shipbuilding industry due to its high strength to weight ratio. Laser welding is a crucial technology enabling reduction of thermal distortion of the weld assemblies and enhancing productivity, but its application to these alloys is far from being a reliable technology. In this work a comparative study has been carried out on the

A. Ancona; T. Sibillano; L. Tricarico; R. Spina; P. M. Lugarà; G. Basile; S. Schiavone

2005-01-01

490

Hot torsion tests to model the deformation behavior of aluminium alloys at hot working temperatures  

Microsoft Academic Search

Knowledge of the deformation behavior of aluminium alloys at hot working temperatures is very important for high temperature manufacturing processes such as hot extrusion. Hot torsion tests were adopted to model this property in this paper. Constitutive equations for stress and strain were developed based on the functional relationship between torque and twist, which enables the material constants to be

M Zhou; M. P Clode

1997-01-01

491

Evidence on the corrosion-induced hydrogen embrittlement of the 2024 aluminium alloy  

Microsoft Academic Search

The present work aims to provide evidence of corrosion-induced hydrogen embrittlement of the aircraft aluminium alloy 2024. An extensive experimental investigation involving metallographic and fractographic analyses as well as mechanical testing was performed. The corrosion exposure led to a moderate reduction in yield and ultimate tensile stress and ad ramatic reduction in tensile ductility. Metallographic investigation of the specimens revealed

P. V. PETROYIANNIS; E. KAMOUTSI; A. L. T. H. KERMANIDIS; S. G. PANTELAKIS; V. BONTOZOGLOU; G. N. HAIDEMENOPOULOS

2005-01-01

492

Antibacterial drugs as corrosion inhibitors for corrosion of aluminium in hydrochloric solution  

Microsoft Academic Search

The corrosion behavior of aluminium in 2 M HCl solution in the absence and presence of four compounds of antibacterial drug was investigated using hydrogen evolution, weight loss, and potentiostatic polarization techniques. It was found that, the inhibition efficiency of these compounds depends on their concentration and chemical structure. The inhibitive action of these compounds was discussed in terms of

M Abdallah

2004-01-01

493

Lanthanide compounds as environmentally-friendly corrosion inhibitors of aluminium alloys: a review  

Microsoft Academic Search

Currently, chromates are among the most common substances used as inhibitors or incorporated in anticorrosive pretreatments of aluminium alloys. However, these compounds are highly toxic and their use produces serious environmental hazards. Consequently, an intense research effort is being undertaken to replace chromates by more ecological compounds. In recent years, several authors have begun studies of the behaviour of lanthanide

M. Bethencourt; F. J. Botana; J. J. Calvino; M. Marcos; M. A. RodrÍguez-Chacón

1998-01-01

494