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1

New Developments of Laser Processing Aluminium Alloys via Additive Manufacturing Technique  

Microsoft Academic Search

The significance of this research lies in its potential to create an Additive Manufacturing technology of novel lightweight materials for industrial applications. The work reported here focuses on studies performed with low power fiber laser and investigates the feasibility of introducing high strength aluminium alloys and custom developed Al powder systems to the Selective Laser Melting (SLM) process. Al-Si powder

Konrad Bartkowiak; Sven Ullrich; Thomas Frick; Michael Schmidt

2011-01-01

2

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

3

Effects of additional filtration on image quality in dental radiography: comparison of niobium with aluminium.  

PubMed

Niobium filtration was compared with additional aluminium filtration with respect to the image quality of dental radiographs. An aluminium phantom was constructed which produced densities similar to those found in periapical regions and in enamel. Eight beam qualities were investigated and objective evaluation of the films was made by 20 observers with respect to any effects on radiographic contrast and successful identification of a pattern of holes in the phantom. Radiographic contrast decreased linearly as the half-value layer increased (r2 = 0.960, P < 0.0005), confirming the negative relationship between contrast and half-value layer as previously shown. No specific effect of niobium filtration on radiographic contrast was demonstrated. The number of successful identifications decreased with increasing half-value layer. A regression analysis in the total and dark zones yielded r2 values of 0.937 and 0.943 (P < 0.0005). Similar analyses for both the light and overall zones showed weaker relationships (r2 = 0.734 and 0.742: P = 0.007 and 0.006 respectively). Niobium reduces successful identification to the same extent as equivalent aluminium filtration. PMID:1397460

McDonnell, D; Price, C

1992-05-01

4

The Effects of Zinc Additions on the Corrosion Susceptibility of Aluminium Alloys in Various Tetraoxosulphate (VI) Acid Environments  

Microsoft Academic Search

The influence of zinc additions on the corrosion behaviour of aluminium alloys in H2SO4 solution of varying concentrations has been investigated. Aluminium-zinc alloys of 1.0, 2.0, 2.5, 3.5 and 4.0% zinc by weight were cast and machined to cuboidal test coupons of initial surface area averaging 12.71 cm2. The coupons were then weighed and immersed into beakers containing 0.5 M

C. E. Ekuma; N. E. Idenyi; A. E. Umahi

2007-01-01

5

Damping capacity of in situ TiB 2 particulates reinforced aluminium composites with Ti addition  

Microsoft Academic Search

The damping capacity of in situ aluminium (Al)\\/TiB2 composite and composite with Ti excess was investigated. The composites were fabricated with an exothermic reaction process via K2TiF4 and KBF4 salts. The damping behavior of materials over a temperature range of 30–300°C was investigated using a dynamic mechanical thermal analyzer. Experimental findings indicate that damping capacity of composite with Ti excess

Yijie Zhang; Naiheng Ma; Haowei Wang; Yongkang Le; Xianfeng Li

2007-01-01

6

Effect of Alloy Additions on Electromigration Failures in Thin Aluminium Films  

Microsoft Academic Search

In earlier work with aluminum thin films, electromigration through grain boundary diffusion has been found to be reduced by the addition of small amounts of copper and not to be affected by additions of silver and gold. Additions of other alloying elements having large atomic-size differences with respect to aluminum, namely, magnesium, nickel, and chromium, have now also been shown

A. Gangulee; F. M. D'Heurle

1971-01-01

7

Aluminium content of some processed foods, raw materials and food additives in China by inductively coupled plasma–mass spectrometry  

Microsoft Academic Search

The level of aluminium in 178 processed food samples from Shenzhen city in China was evaluated using inductively coupled plasma–mass spectrometry. Some processed foods contained a concentration of up to 1226?mg\\/kg, which is about 12 times the Chinese food standard. To establish the main source in these foods, Al levels in the raw materials were determined. However, aluminium concentrations in

Gui-Fang Deng; Ke Li; Jing Ma; Fen Liu; Jing-Jing Dai; Hua-Bin Li

2011-01-01

8

Effect of minor Sc additions on structure, age hardening and tensile properties of aluminium alloy AA8090 plate  

Microsoft Academic Search

The grain structure, age hardening response, precipitate structure and tensile properties of AA8090 alloy plate without and with minor additions of Sc were investigated. Primary aluminide particles were present in all alloys. Sc additions ?0.43% resulted in refinement of the as-cast grain structure. Further investigations on 0.11% and 0.22% Sc containing alloys showed that the subgrain size was finer while

Vijaya Singh; K. Satya Prasad; Amol A. Gokhale

2004-01-01

9

Corrosion fatigue behaviour of 5083-H111 and 6061-T651 aluminium alloy welds.  

E-print Network

??In addition to being one of the highest strength non-heat treatable aluminium alloys, magnesium-alloyed wrought aluminium 5083 displays excellent corrosion resistance and good weldability. Aluminium… (more)

Mutombo, Faustin Kalenda

2012-01-01

10

Addition  

NSDL National Science Digital Library

Addition games First let\\'s practice our Fast Addition Let\\'s try to beat the Addition Machine You can help the bear while he is Catching Tens. Try to make your own picture using addition skills at the Hidden Picture Addition addition game. ...

Mchale, Ms.

2007-10-25

11

Aluminium in human sweat.  

PubMed

It is of burgeoning importance that the human body burden of aluminium is understood and is measured. There are surprisingly few data to describe human excretion of systemic aluminium and almost no reliable data which relate to aluminium in sweat. We have measured the aluminium content of sweat in 20 healthy volunteers following mild exercise. The concentration of aluminium ranged from 329 to 5329?g/L. These data equate to a daily excretion of between 234 and 7192?g aluminium and they strongly suggest that perspiration is the major route of excretion of systemic aluminium in humans. PMID:24239230

Minshall, Clare; Nadal, Jodie; Exley, Christopher

2014-01-01

12

Evidence of aluminium accumulation in aluminium welders.  

PubMed Central

Using atomic absorption spectrometry the aluminium concentrations in blood and urine and in two iliac bone biopsies obtained from welders with long term exposure to fumes containing aluminium were measured. The urinary excretion of two workers who had welded for 20 and 21 years varied between 107 and 351 micrograms Al/l, more than 10 times the concentration found in persons without occupational exposure. Urinary aluminium excretion remained high many years after stopping exposure. Blood and bone aluminium concentrations (4-53 micrograms Al/l and 18-29 micrograms Al/g respectively) were also raised but not to the same extent as urine excretion. It is concluded that long term exposure to aluminium by inhalation gives rise to accumulation of aluminium in the body and skeleton of health persons, and that the elimination of retained aluminium is very slow, in the order of several years. PMID:1954151

Elinder, C G; Ahrengart, L; Lidums, V; Pettersson, E; Sjögren, B

1991-01-01

13

Additives  

NASA Technical Reports Server (NTRS)

The chemistry of lubricant additives is discussed to show what the additives are chemically and what functions they perform in the lubrication of various kinds of equipment. Current theories regarding the mode of action of lubricant additives are presented. The additive groups discussed include the following: (1) detergents and dispersants, (2) corrosion inhibitors, (3) antioxidants, (4) viscosity index improvers, (5) pour point depressants, and (6) antifouling agents.

Smalheer, C. V.

1973-01-01

14

Human exposure to aluminium.  

PubMed

Human activities have circumvented the efficient geochemical cycling of aluminium within the lithosphere and therewith opened a door, which was previously only ajar, onto the biotic cycle to instigate and promote the accumulation of aluminium in biota and especially humans. Neither these relatively recent activities nor the entry of aluminium into the living cycle are showing any signs of abating and it is thus now imperative that we understand as fully as possible how humans are exposed to aluminium and the future consequences of a burgeoning exposure and body burden. The aluminium age is upon us and there is now an urgent need to understand how to live safely and effectively with aluminium. PMID:23982047

Exley, Christopher

2013-10-01

15

Biomedical aspects of aluminium.  

PubMed

About 2.5 mg of aluminium is absorbed daily with food; it then undergoes minimal absorption via the gastrointestinal tract (0.1%) and total excretion of the absorbed dose via the kidneys. The concentrations of aluminium in blood of non-exposed subjects with normal renal function are extremely low (1-3 micrograms/L). Until the beginning of the 1970's aluminium was considered to be of little toxicological interest, but in 1972 a neurological syndrome due to aluminium intoxication was described in dialysis patients in the UK and in 1973 Canadian research workers speculated on the role of aluminium in Alzheimer's disease (senile or presenile dementia), even though this does not at present have wide support. Al intoxication in dialysis patients can be prevented if the Al concentration in the dialysis solution is kept below 10 micrograms/L. No cases have been reported of systemic intoxication due to aluminium in occupationally exposed subjects. Al in plasma values of 5-15 micrograms/L have been reported in exposed workers, which are 10 times lower than the values observed in dialysis patients with encephalopathic symptoms. However, rare cases of occupational pulmonary fibrosis have been reported where an etiopathological role of aluminium was suspected. Nevertheless, it has been demonstrated that the alumina used in primary aluminium production lacks any fibrogenic potential. PMID:1297060

Schlatter, C

1992-01-01

16

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

17

Effect of aluminium additions on wettability and intermetallic compound (IMC) growth of lead free Sn (2 wt. % Ag, 5 wt. % Bi) soldered joints  

NASA Astrophysics Data System (ADS)

The effect of a trace Al addition (0, 0.01, 0.05 and 0.1 wt. %) in the Sn-2Ag-5Bi solder alloy on wettability and intermetallic compound (IMC) formation of the alloy was investigated. The interface between the solder and a Cu(17 ?m)/Ni(4 ?m)/Au (0.02 ?m) under bump metallized (UBM) substrate was studied. The microstructure of the bulk solder and the interface of the soldered joints was observed in a scanning electron microscope (SEM), and the thickness of the interface reaction layers was estimated. Various IMC phases were identified by energy dispersive spectroscopy (EDS) and by the electron probe micro analyzer (EPMA). The experimental results indicated that the addition of 0.01 wt. % Al in the Sn-2Ag-5Bi solder alloy significantly improved the wettability of the solder more than the other Al additions did. The IMC layer between the bulk Sn-2Ag5Bi-0.01Al solder and the Cu/Ni/Au UBM substrate was almost uniform and thinner than those between the solders containing 0, 0.05, and 0.1 wt. % Al and their respective Cu/Ni/Au UBM substrates. Furthermore, the growth rate of the IMC layer between the Sn-2Ag-5Bi-0.01Al solder and Cu/Ni/Au UBM after 1 to 10 reflow times was lower than that of the IMC layer between the Sn-2Ag-5Bi solder and Cu/Ni/Au UBM. The IMCs in the solder joint interface (e.g., Ni3Sn4) of the Sn-2Ag-5Bi-0.01Al solder were well distributed near the Bi and fine Ag3Sn. The addition of 0.01 wt. % Al in the Sn-2Ag-5Bi solder yielded the best wetting properties for the solder and the minimum growth rate of the IMCs because it increased the nucleation rate of Ag3Sn and uniformly segregated the Bi phase.

Lee, Hee Yul; Sharma, Ashutosh; Kee, Se Ho; Lee, Young Woo; Moon, Jung Tak; Jung, Jae Pil

2014-09-01

18

Organic electrolytes for corrosion testing of aluminium and Al-Li binary alloys  

Microsoft Academic Search

The electrochemical behavior of high purity aluminium and Al-Li alloy has been investigated in various organic environments. Various lithium- and aluminium-compatible solvents were considered before selecting propylene carbonate (PC) and tetrahydrofuran (THF) with addition of either chloride or perchlorate ions. THF finally proved to be the most suitable solvent for these tests. The aluminium dissolution reaction in a THF environment

F. Dalard; A. B. Rais

1989-01-01

19

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)

20

Aluminium Electroplating on Steel from a Fused Bromide Electrolyte  

SciTech Connect

A quaternary bromide bath (LiBr-KBr-CsBr-AlBr3) was used to electro-coat aluminium on steel substrates. The electrolyte was prepared by the addition of AlBr3 into the eutectic LiBr-KBr-CsBr melt. A smooth, thick, adherent and shiny aluminium coating could be obtained with 80 wt.% AlBr3 in the ternary melt. The SEM photographs of the coated surfaces suggest the formation of thick and dense coatings with good aluminium coverage. Both salt immersion and open circuit potential measurement suggest that the coatings did display good corrosion-resistance behavior. Annealing of the coated surfaces, prior to corrosion tests, suggested the robustness of the metallic aluminium coating in preventing the corrosion of the steel surfaces. Studies also indicated that the quaternary bromide plating bath can potentially provide a better aluminium coating on both ferrous and non-ferrous metals, including complex surfaces/geometries.

Prabhat Tripathy; Laura Wurth; Eric Dufek; Toni Y. Gutknecht; Natalie Gese; Paula Hahn; Steven Frank; Guy Fredrickson; J Stephen Herring

2014-08-01

21

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

22

Occupational asthma caused by aluminium welding  

Microsoft Academic Search

Work-related asthma has been documented in workers employed in the primary aluminium industry and in the production of aluminium salts. The role of aluminium in the development of occupational asthma has, however, never been con- vincingly substantiated. We investigated a subject who experienced asthmatic reactions related to manual metal arc welding on aluminium. Challenge exposure to aluminium welding with flux-coated

O. Vandenplas; J. P. Delwiche; M. L. Vanbilsen; J. Joly; D. Roosels

1998-01-01

23

Risk of increased aluminium burden in the Indian population: contribution from aluminium cookware  

Microsoft Academic Search

Aluminium (Al) is a well-established potential neurotoxin in addition to its role in the aetiopathogenesis of certain disorders related to bone and blood. Food and water are the major sources of Al ingestion in normal population groups. Al content of certain cooked foods was therefore analysed to assess its daily burden in the Indian population. Significant levels of Al were

M Neelam; M. S Bamji; M Kaladhar

2000-01-01

24

Reactivities of aluminium and aluminium-magnesium alloy powders in polymeric composites  

Microsoft Academic Search

Polymeric compositions containing Al-Mg alloys show higher reactivities, in comparison with similar compositions containing aluminium. This is observed irrespective of the amount of oxidizer, type of oxidizer used, type of polymeric binder, and over a range of the particle sizes of the metal additive. This is evident from the higher calorimetric values obtained for compositions containing the alloy, in comparison

S. Deevi

1996-01-01

25

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

26

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

27

Spectrophotometric and derivative spectrophotometric determination of aluminium with Hydroxynaphthol Blue.  

PubMed

The reaction of aluminium(III) with Hydroxynaphtol Blue (HNB) in aqueous media at apparent pH 5.5 results in a red complex that is stable for at least 4 hr. Beer's Law is obeyed up to 1.6 microg/ml of aluminium(III) with an apparent molar absorptivity of 1.66 x 10(4) l.mol(-1). cm(-1) at 569 nm. This paper proposes procedures for aluminium(III) determination by ordinary and first-derivative spectrophotometry. The results demonstrated that the linear dynamic range is 0.03-1.60 microg/ml for ordinary spectrophotometry and 11.8-320.0 ng/ml for first derivative spectrophotometry. The HNB is not selectivity for aluminium, but the addition of EDTA allows the aluminium determination in the presence of accepted amounts of Ca(II), Mg(II), Mn(II), Ba(II), Sr(II), Cd(II), Pb(II), La(III), In(III), Bi(III) and Zn(II). The interference of Cu(II) and Hg(II) can be masked by thiosulphate. Ions such as UO(2)(II), Mo(VI), Co(II), Ti(IV) and PO(4)(III) do interfere seriously. This method was applied for aluminium determination in copper-base alloy, zinc-base alloy, magnesium-base alloy, iron ore, manganese ore, cement, dolomite, feldspar and limestone. The results indicated high accuracy and precision. PMID:18966113

Ferreira, S L; Leite, N O; Dantas, A F; de Andrade, J B; Costa, A C

1994-10-01

28

Aluminium Pneumoconiosis II. Effect on the Rat Lung of Intratracheal Injections of Stamped Aluminium Powders Containing Different Lubricating Agents and of a Granular Aluminium Powder  

PubMed Central

Three stamped aluminium powders were injected into the lungs of rats. One powder contained stearine and another mineral oil, whilst the third had had its lubricant removed. The powders produced a rapid and marked fibrosis of equal severity. It is concluded that aluminium rather than any additive in the powders is the fibrogenic agent. The protective action of stearine demonstrated in vitro was not confirmed in vivo, suggesting that pulmonary fibrosis may also occur in men handling stearine-containing powders. Such a case has recently been reported by McLaughlin et al. (1962), but this is exceptional to the general industrial experience. A granular aluminium powder was also injected into the lungs of rats. In accordance with the results of in vitro experiments, this produced only minimal fibrosis, contrasting strongly with the action of the stamped powders. Images PMID:14072617

Corrin, B.

1963-01-01

29

Aluminium Involvement in Neurotoxicity  

PubMed Central

The aetiology of neurodegenerative diseases (ND) seems to involve susceptibility genes and environmental factors. Toxic metals are considered major environmental pollutants. Following our study of a case of multiple sclerosis (MS) improvement due to removal of aluminium (Al) and other toxic metals, we have examined the possible relationship between Al intoxication and ND. We used the slow intravenous treatment with the chelating agent EDTA (calcium disodium ethylene diamine tetraacetic acid) (chelation test) to remove Al and detected it in the urine collected from the patients for 12 hours. Patients affected by MS represented 85.6% of total ND. Al was present in 44.8% of cases comprehensive of ND and healthy patients. Al levels were significantly higher in ND patients than in healthy subjects. We here show that treatment of patients affected by Al burden with ten EDTA chelation therapies (EDTA intravenous administration once a week) was able to significantly reduce Al intoxication. PMID:25243176

Fulgenzi, Alessandro; Vietti, Daniele; Ferrero, Maria Elena

2014-01-01

30

Effect of CH4 Ion Implantation in Pure Aluminium  

NASA Astrophysics Data System (ADS)

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 (AFM). Microstructure of the modified surfaces after ion implantation has been obtained by X-ray diffraction technique and Raman spectroscopy. Formation of aluminium carbide (Al4C3) was confirmed by XRD results at implantation doses of 3 × 1017 and 6 × 1017 ions/cm2. In addition, it was observed that when the ion dose is increased, orientation of aluminium planes change from (2 2 0) to (2 0 0). Corrosion test was performed and compared for implanted and un-implanted samples. The results showed that corrosion resistivity increase by accumulation of ion dose.

Sari, A. H.; Jabbari, A. R.; Ghoranneviss, M.

2011-08-01

31

Influence of aluminium precursor on physico-chemical properties of aluminium hydroxides and oxides  

Microsoft Academic Search

Summary  An attempt to obtain aluminium hydroxide that could give aluminium oxides of increased thermal stability was made. Aluminium\\u000a hydroxide was precipitated during a hydrolysis of aluminium chloride in ammonia medium. The influence of preparative conditions,\\u000a such as a dosing rate of aluminium precursor, pH, duration of the precipitate refluxing and temperature of calcination, on\\u000a the properties of obtained hydroxides and

Olga Kluk-P?osko?ska; D. Szychowski

32

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

2013-01-01

33

HEAT REFLECTIVE COATINGS OF ALUMINIUM  

Microsoft Academic Search

Thermal emissivity and solar reflectance are important surface characteristics to obtain energy-savings and increased thermal comfort in buildings. Aluminium products used for building applications are normally coated or anodised for protection and visual appearance. Both surface treatments give very high thermal emissivity levels, typically e = 0.85 - 0.9. High emissivity levels are normally unfavourable for building applications. A coating

Merete Hallenstvet; Jostein Mårdalen; Helene Bolm; Volker Rekowski; Steinar Tanem; John Erik Lein

34

Aluminium toxicity in chronic renal insufficiency  

SciTech Connect

Aluminium is a ubiquitous element in the environment and has been demonstrated to be toxic, especially in individuals with impaired renal function. Not much is known about the biochemistry of aluminium and the mechanisms of its toxic effects. Most of the interest in aluminium has been in the clinical setting of the hemodialysis unit. Here aluminium toxicity occurs due to contamination of dialysis solutions, and treatment of the patients with aluminium-containing phosphate binding gels. Aluminium has been shown to be the major contributor to the dialysis encephalopathy syndrome and an osteomalacic component of dialysis osteodystrophy. Other clinical disturbances associated with aluminium toxicity are a microcytic anemia and metastatic extraskeletal calcification. Aluminium overload can be treated effectively by chelation therapy with desferrioxamine and hemodialysis. Aluminium is readily transferred from the dialysate to the patient's -bloodstream during hemodialysis. Once transferred, the aluminium is tightly bound to non-dialysable plasma constituents. Very low concentrations of dialysate aluminium in the range of 10-15 micrograms/l are recommended to guard against toxic effects. Very few studies have been directed towards the separation of the various plasma species which bind eluminium. Gel filtration chromatography has been used to identify five major fractions, one of which is of low molecular weight and the others appear to be protein-aluminium complexes. Recommendations on aluminium monitoring have been published and provide safe and toxic concentrations. Also, the frequency of monitoring has been addressed. Major problems exist with the analytical methods for measuring aluminium which result from inaccurate techniques and contamination difficulties. 136 references.

Savory, J.; Bertholf, R.L.; Wills, M.R.

1985-08-01

35

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

36

Reconstruction of 2D Al3Ti on TiB2 in an aluminium melt  

Microsoft Academic Search

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

T Qin; Z Fan

2012-01-01

37

The effect of grain refining on the microsegregation of aluminium–magnesium alloy 5182  

Microsoft Academic Search

Aluminium alloy 5182 (AA5182) contains approximately 4.5%Mg as its principal alloying addition, and is most commonly used to make the lid of the aluminium can. With a view to the possible future development of a micro-macro model to describe the casting of this alloy, the effect of grain refinement on the microsegregation of magnesium in industrial rolling ingots of AA5182

A. M. Glenn; S. P. Russo; J. D. Gorman; P. J. K. Paterson

2001-01-01

38

Quenching of vacancies in pure aluminium and in dilute aluminium-indium and aluminium-magnesium alloys  

Microsoft Academic Search

The increase in resistivity due to quenched-in vacancies was measured for zone-refined aluminium and two aluminium alloys based upon zone-refined aluminium containing indium and magnesium respectively. The alloys were made by levitation melting to minimize pick-up of other impurities. For the pure metal E? , the activation energy for the formation of a vacancy, was found to be 0·76±0·02 ev,

F. C. Duckworth; J. Burke

1966-01-01

39

Influenceof aluminium precursor on physico-chemical properties of aluminium hydroxidesand oxides  

Microsoft Academic Search

An attempt\\u000a to obtain aluminium hydroxide that could give aluminium oxides of increased\\u000a thermal stability was made. Aluminium hydroxide was precipitated during a\\u000a hydrolysis of aluminium chloride in ammonia medium. The influence of preparative\\u000a conditions, such as a dosing rate of aluminium precursor, pH, duration of\\u000a the precipitate refluxing and temperature of calcination, on the properties\\u000a of obtained hydroxides and

Barbara Pacewska; Olga Kluk-P?osko?ska; D. Szychowski

2006-01-01

40

Aluminium Pneumoconiosis I. In Vitro Comparison of Stamped Aluminium Powders Containing Different Lubricating Agents and a Granular Aluminium Powder  

PubMed Central

The discrepancy in previous reports of the action of aluminium on the lung may be explained by differences between stamped and granular aluminium powders. A stamped powder of the variety causing pulmonary fibrosis showed a brisk reaction with water, but a granular powder was unreactive. This difference is primarily due to the granular particles being covered by inert aluminium oxide, the formation of which is partially prevented in the stamping process by stearine and mineral oil. The reactivity of the flake-like stamped particles is also dependent on their large surface area per unit volume. The appearance of aluminium pneumoconiosis in Britain is explained by the introduction of mineral oil into the stamping industry for, in contrast to stearine, mineral oil permits the powder to react with water. The lung damage is believed to be caused by a soluble form of aluminium. PMID:14072616

Corrin, B.

1963-01-01

41

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

42

MOCVD of aluminium oxide films using aluminium ?-diketonates as precursors  

NASA Astrophysics Data System (ADS)

Deposition of Al203 coatings by CVD is of importance because they are often used as abrading material in cemented carbide cutting tools. The conventionally used CVD process for Al203 involves the corrosive reactant AICl3. In this paper, we report on the thermal characterisation of the metalorganic precursors namely aluminium tris-tetramethyl-heptanedionate [ Al(thd)3] and aluminium tris-acetylacetonate [ Al(acac)3] and their application to the CVD of Al203 films. Crystalline A1203 films were deposited by MOCVD at low temperatures by the pyrolysis of Al(thd)3 and AI(acac)3. The films were deposited on a TiN-coated tungsten carbide (TiN/WC) and Si(100) substrates in the temperature range 500-1100 °C. The as-deposited films were characterised by x-ray diffraction, optical microscopy, scanning and transmission electron microscopy, Auger electron spectroscopy. The observed crystallinity of films grown at low temperatures, their microstructure, and composition may be interpreted in terms of a growth process that involves the melting of the metalorganic precursor on the hot growth surface.

Devi, A.; Shivashankar, S. A.; Samuelson, A. G.

2002-06-01

43

Oxidative stress and mitochondrial dysfunction in aluminium neurotoxicity and its amelioration: a review.  

PubMed

Aluminium is light weight and toxic metal present ubiquitously on earth which has gained considerable attention due to its neurotoxic effects. The widespread use of products made from or containing aluminium is ensuring its presence in our body. There is prolonged retention of a fraction of aluminium that enters the brain, suggesting its potential for accumulation with repeated exposures. There is no known biological role for aluminium within the body but adverse physiological effects of this metal have been observed in mammals. The generation of oxidative stress may be attributed to its toxic consequences in animals and humans. The oxidative stress has been implicated in pathogenesis of various neurodegenerative conditions including Alzheimer's disease and Parkinson's disease. Though it remains unclear whether oxidative stress is a major cause or merely a consequence of cellular dysfunction associated with neurodegenerative diseases, an accumulating body of evidence implicates that impaired mitochondrial energy production and increased mitochondrial oxidative damage is associated with the pathogenesis of neurodegenerative disorders. Being involved in the production of reactive oxygen species, aluminium may impair mitochondrial bioenergetics and may lead to the generation of oxidative stress. In this review, we have discussed the oxidative stress and mitochondrial dysfunctions occurring in Al neurotoxicity. In addition, the ameliorative measures undertaken in aluminium induced oxidative stress and mitochondrial dysfunctions have also been highlighted. PMID:24560992

Kumar, Vijay; Gill, Kiran Dip

2014-03-01

44

Surface mechanical behaviour of composite Ni-P-fly ash/zincate coated aluminium alloy  

NASA Astrophysics Data System (ADS)

Ni-P-fly ash coatings were produced on zincate coated 5083 wrought aluminium alloy substrates with the aid of an electroless deposition technique. Structural and chemical characterization of the produced coatings was performed with the aid of X-ray diffraction (XRD), scanning electron microscopy (SEM) and electron dispersive X-ray analysis (EDS) techniques. The Ni-P-fly ash coating was found to consist of an amorphous Ni-P matrix with dispersed fly ash particles. The wear resistance of the Ni-P-fly ash coating on zincate treated aluminium alloy was observed to be higher than that of the bare aluminium alloy, when sliding against a stainless steel counterface. In addition, the adhesion between the Ni-P-fly ash/zincate coating and the aluminium alloy substrate was also studied with a scratch testing apparatus. The adhesion strength of Ni-P-fly ash/zincate coating on the aluminium alloy substrate was observed to be higher in comparison to the Ni-P/zincate coating on the same aluminium alloy.

Panagopoulos, C. N.; Georgiou, E. P.

2009-04-01

45

The role of iron(iii) and tartrate in the zincate immersion process for plating aluminium  

Microsoft Academic Search

The zincate immersion process is a commercial process used to treat aluminium prior to electroplating. Superior zinc coatings are obtained through modifications to the original process. One such modification involves the addition of ferric chloride, complexed with potassium sodium tartrate, to the plating baths. This paper describes a detailed investigation into the function of these additives. It was found that

S. G. ROBERTSON; I. M. RITCHIE

1997-01-01

46

Aluminium in Biological Environments: A Computational Approach  

PubMed Central

The increased availability of aluminium in biological environments, due to human intervention in the last century, raises concerns on the effects that this so far “excluded from biology” metal might have on living organisms. Consequently, the bioinorganic chemistry of aluminium has emerged as a very active field of research. This review will focus on our contributions to this field, based on computational studies that can yield an understanding of the aluminum biochemistry at a molecular level. Aluminium can interact and be stabilized in biological environments by complexing with both low molecular mass chelants and high molecular mass peptides. The speciation of the metal is, nonetheless, dictated by the hydrolytic species dominant in each case and which vary according to the pH condition of the medium. In blood, citrate and serum transferrin are identified as the main low molecular mass and high molecular mass molecules interacting with aluminium. The complexation of aluminium to citrate and the subsequent changes exerted on the deprotonation pathways of its tritable groups will be discussed along with the mechanisms for the intake and release of aluminium in serum transferrin at two pH conditions, physiological neutral and endosomatic acidic. Aluminium can substitute other metals, in particular magnesium, in protein buried sites and trigger conformational disorder and alteration of the protonation states of the protein's sidechains. A detailed account of the interaction of aluminium with proteic sidechains will be given. Finally, it will be described how alumnium can exert oxidative stress by stabilizing superoxide radicals either as mononuclear aluminium or clustered in boehmite. The possibility of promotion of Fenton reaction, and production of hydroxyl radicals will also be discussed. PMID:24757505

Mujika, Jon I; Rezabal, Elixabete; Mercero, Jose M; Ruipérez, Fernando; Costa, Dominique; Ugalde, Jesus M; Lopez, Xabier

2014-01-01

47

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

2011-07-01

48

Aluminium toxicity and nodulation of Trifolium repens  

Microsoft Academic Search

Summary  Effects of aluminium on theTrifolium repens var Huia-Rhizobium trifolii strain HP3 symbiosis were studied using an axenic solution-culture system. With, 10 ?M phosphate, 50 ?M aluminium reduced or inhibited root elongation at pH<5.0, root hair formation at pH< 5.0–5.5, and Rhizobium multiplication\\u000a in the rhizosphere and nodule formation at pH<6.0. In the absence of aluminium, root elongation and root hair

M. Wood; J. E. Cooper; A. J. Holding

1984-01-01

49

Elevated brain aluminium and early onset Alzheimer’s disease in an individual occupationally exposed to aluminium: a case report  

PubMed Central

Introduction Aluminium is a known neurotoxin and occupational exposure to aluminium has been implicated in neurological disease including Alzheimer’s disease. Here we present the first comprehensive and unequivocal data demonstrating significantly elevated brain aluminium content in an individual occupationally exposed to aluminium. Case presentation A 66-year-old Caucasian man who died with Alzheimer’s disease showed significantly elevated brain aluminium content, 2.98 (2.73) ?g/g dry weight, n?=?46, following occupational exposure to aluminium over a period of 8 years. Conclusions That the individual developed an early onset aggressive form of Alzheimer’s disease suggests a role for aluminium in disease aetiology. That the exposure to aluminium was through occupational exposure to aluminium dust suggests a prominent role for the olfactory system and lungs in the accumulation of aluminium in the brain. PMID:24513181

2014-01-01

50

Mechanochemically activated nano-aluminium: Oxidation behaviour  

Microsoft Academic Search

Nanocrystalline aluminium powder has been prepared by high-energy ball milling of flaked micron-sized aluminium powder in the presence of 10 wt% of graphite under argon atmosphere. The structure and chemical composition of as-prepared nanocomposites and the their thermally induced changes are studied by X-ray diffraction (XRD), transmission electron microscopy (TEM), and simultaneous TG-DTA technique (SDT). TEM studies reveal that the

A. Pivkina; A. Streletskii; I. Kolbanev; P. Ul'yanova; Yu. Frolov; P. Butyagin; J. Schoonman

2004-01-01

51

Aluminium corrosion in room temperature molten salt  

Microsoft Academic Search

Aluminium corrosion in a room temperature molten salt is studied to validate the use of a new kind of electrolyte in a lithium battery. Two solvents have been compared, the room temperature molten salt ethyl-methyl-imidazolium bis(trifluoromethane-sulfonyl)imide (EMI-TFSI), and the liquid organic solvent EC\\/DMC containing the lithium salt LiTFSI. After confirmation of high aluminium corrosion in the liquid solvent, the results

Béatrice Garcia; Michel Armand

2004-01-01

52

Adrenocortical involvement in aluminium phosphide poisoning.  

PubMed

The effect of aluminium phosphide (AlP) which is a systemic poison on the adrenal cortex was studied in 30 patients of AlP poisoning. A significant rise in the plasma cortisol level (greater than 1048 nmol/l) was observed in the twenty patients. Mortality was 50 per cent. Autopsy study could be undertaken only in 10 patients. Histopathology showed mild to moderate changes. In the rest (10 patients), the adrenal cortex was critically involved and the cortisol level failed to rise beyond normal levels (less than 690 nmol/l). The histopathology revealed severe changes (complete lipid depletion, haemorrhage, necrosis etc.) and all these patients died. In the critically ill patients, the cortisol levels remained low because of severe adreno-cortical involvement. The changes in the adrenal cortex could be due to shock or to cellular toxic effect of phosphine. The histopathological changes in various viscera showed congestion, edema and cellular infiltration. In the heart, there were patchy areas of necrosis, while the liver showed fatty changes and the lungs showed, in addition areas of gray/red hepatization. There was no adrenal apoplexy or extensive haemorrhage that could explain shock in these patients. Cardiogenic shock could not be confirmed due to lack of facilities for haemodynamic monitoring, but there was histopathological evidence in support of cardiovascular shock. PMID:2620956

Chugh, S N; Ram, S; Sharma, A; Arora, B B; Saini, A S; Malhotra, K C

1989-08-01

53

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

54

Threshold creep behaviour of discontinuous aluminium and aluminium alloy matrix composites: An overview  

Microsoft Academic Search

Several sets of creep data for aluminium and aluminium alloy matrix composites reinforced by silicon carbide particulates, silicon carbide whiskers or alumina short fibres are analysed. It is shown that for this class of discontinuous composites the threshold creep behaviour is inherent. Applying the concept of threshold stress, the true stress exponent of minimum creep strain rate of approximately 5

J. ?adek; H. Oikawa; V. Šustek

1995-01-01

55

Aluminium in the blood and urine of industrially exposed workers.  

PubMed Central

Blood and urine aluminium concentrations were studied in industrially exposed workers using electrothermal atomic absorption spectrometry. Welders and workers making aluminium powder and aluminium sulphate had higher concentrations in blood and urine than non-exposed referents. Workers in the electrolytic production of aluminium had higher urine but not blood concentrations than the referents. Thus aluminium was found to be absorbed by all industrially exposed workers. Blood concentrations were lower than those presumably associated with aluminium induced encephalopathy in patients receiving dialysis. PMID:6871119

Sjögren, B; Lundberg, I; Lidums, V

1983-01-01

56

Blood and urine concentrations of aluminium among workers exposed to aluminium flake powders.  

PubMed Central

In a group of workers exposed to aluminium flake powders, blood and urine concentrations of aluminium were assessed before and after vacation. Another group was investigated after retirement. Workers currently exposed to aluminium flake powders had urinary concentrations of the metal 80-90 times higher than those in occupationally non-exposed referents. The calculated half life for concentrations of aluminium in urine was five to six weeks based on four to five weeks of non-exposure. Among the retired workers the half lives varied from less than one up to eight years and were related to the number of years since retirement. These results indicate that aluminium is retained and stored in several compartments of the body and eliminated from these compartments at different rates. PMID:1998604

Ljunggren, K G; Lidums, V; Sjögren, B

1991-01-01

57

Blood and urine concentrations of aluminium among workers exposed to aluminium flake powders.  

PubMed

In a group of workers exposed to aluminium flake powders, blood and urine concentrations of aluminium were assessed before and after vacation. Another group was investigated after retirement. Workers currently exposed to aluminium flake powders had urinary concentrations of the metal 80-90 times higher than those in occupationally non-exposed referents. The calculated half life for concentrations of aluminium in urine was five to six weeks based on four to five weeks of non-exposure. Among the retired workers the half lives varied from less than one up to eight years and were related to the number of years since retirement. These results indicate that aluminium is retained and stored in several compartments of the body and eliminated from these compartments at different rates. PMID:1998604

Ljunggren, K G; Lidums, V; Sjögren, B

1991-02-01

58

Molecular dynamics study on the failure modes of aluminium under decaying shock loading  

NASA Astrophysics Data System (ADS)

We have investigated the failure modes of single crystal aluminium under decaying shock loading by using molecular dynamics simulations. The microstructure evolution during the failure is presented in terms of the central symmetry parameter, and the corresponding pressure and temperature profiles are calculated and discussed. These results explain the failure morphology and mechanical properties under dynamic tension and especially the difference between solid and melted states. In addition, the fracture strength of aluminium is analyzed from surface velocity within acoustic approximation and virial theorem.

Shao, Jian-Li; Wang, Pei; He, An-Min; Duan, Su-Qing; Qin, Cheng-Sen

2013-04-01

59

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

2006-12-21

60

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

61

Pitting corrosion control using regenerative biolms on aluminium 2024 in articial seawater  

E-print Network

Pitting corrosion control using regenerative bio®lms on aluminium 2024 in arti®cial seawater D, CT 06269-3222, USA b Corrosion and Environment Eects Laboratory (CEEL), Department of Materials polyglutamate or polyaspartate, an additional small increase in corrosion inhibition occurred. Corrosion control

Wood, Thomas K.

62

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

SciTech Connect

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.; Sakai, S. [Department of Production Systems Engineering, Toyohashi University of Technology, Tempaku, Toyohashii 441-8580 (Japan); Kato, T. [Nippon POP Rivets and Fasteners Ltd., Hosoda, Noyori-cho, Toyohashi 441-8540 (Japan)

2010-06-15

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

Diffusion bonding stainless steel to alumina using aluminium interlayers  

Microsoft Academic Search

A study has been conducted to identify the effects of fabrication temperatures pressures, times and other variables on the strengths of diffusion-bonded joints between alumina and BS321 stainless steel produced using aluminium foil interlayers. The strengths of the alumina-aluminium and steel-aluminium interfaces were found to be influenced differently by some fabrication parameters, thus increasing the fabrication temperature promoted alumina-aluminium bonding

M. G. Nicholas; R. M. Crispin

1982-01-01

65

Energy Absorption of Monolithic and Fibre Reinforced Aluminium Cylinders  

Microsoft Academic Search

Summary accompanying the thesis: Energy Absorption of Monolithic and Fibre Reinforced Aluminium Cylinders by Jens de Kanter This thesis presents the investigation of the crush behaviour of both monolithic aluminium cylinders and externally fibre reinforced aluminium cylinders. The research is based on analytical work, numerical work and experimental work, which together show a complete picture of the tube axial crush

J. L. C. G. De Kanter

2006-01-01

66

Diffusion Bonding Aluminium Alloys and Composites: New Approaches and Modelling  

E-print Network

Diffusion Bonding Aluminium Alloys and Composites: New Approaches and Modelling Amir A. Shirzadi.D. research was to develop new joining methods for these materials for which conventional welding methods have of the research, two new methods for TLP diffusion bonding of aluminium-based composites (aluminium alloys

Cambridge, University of

67

Comprehensive study of aluminium alloy plates under compression conditions  

Microsoft Academic Search

Aluminium alloys have been vital for the progress of many technologies during the last decades. In particular, most stiffeners in aerospace structures are composed of aluminium panels often solicited with elastic and plastic bucking under particular boundary and loading conditions. The purpose of this paper is to enhance the difficulties encountered to predict the incipient elastic–plastic buckling for thin aluminium

F. Ayari; A. Zghal; E. Bayraktar

2009-01-01

68

Oxidation-assisted ductility of aluminium nanowires.  

PubMed

Oxidation can drastically change mechanical properties of nanostructures that typically have large surface-to-volume ratios. However, the underlying mechanisms describing the effect oxidation has on the mechanical properties of nanostructures have yet to be characterized. Here we use reactive molecular dynamics and show that the oxidation enhances the aluminium nanowire ductility, and the oxide shell exhibits superplastic behaviour. The oxide shell decreases the aluminium dislocation nucleation stress by increasing the activation volume and the number of nucleation sites. Superplasticity of the amorphous oxide shell is due to viscous flow as a result of healing of the broken aluminium-oxygen bonds by oxygen diffusion, below a critical strain rate. The interplay between the strain rate and oxidation rate is not only essential for designing nanodevices in ambient environments, but also controls interface properties in large-scale deformation processes. PMID:24887649

Sen, Fatih G; Alpas, Ahmet T; van Duin, Adri C T; Qi, Yue

2014-01-01

69

The binding of phosphonic acids at aluminium oxide surfaces and correlation with passivation of aluminium flake.  

PubMed

Measurements of adsorption isotherms of a series of thirteen mono- and di-phosphonic acids have shown that these bind strongly to the surface of high surface area aluminium trihydroxide. The incorporation of such phosphonates into a suspension of aluminium flake in an aqueous medium, modelling the continuous phase of a water-based paint, greatly suppresses the evolution of hydrogen. Whilst strong binding of the phosphonate to aluminium oxides is an essential criterion for good passivation, other factors such as the hydrophobicity of the ligand are also important in suppressing hydrogen-evolution. PMID:17372645

Cooper, Rachel J; Camp, Philip J; Henderson, David K; Lovatt, Paul A; Nation, David A; Richards, Stuart; Tasker, Peter A

2007-04-01

70

Process and Mechanical Properties: Applicability of a Scandium modified Al-alloy for Laser Additive Manufacturing  

Microsoft Academic Search

The applicability of an aluminium alloy containing scandium for laser additive manufacturing (LAM) is considered. Modified aluminium alloys with a scandium content beyond the eutectic point offer great potential to become a high prioritized aerospace material. Depending on other alloying elements like magnesium or zirconium, strongly required weight reduction, corrosion resistance and improved strength properties of metallic light weight alloys

K. Schmidtke; F. Palm; A. Hawkins; C. Emmelmann

2011-01-01

71

Aluminium corrosion in room temperature molten salt  

NASA Astrophysics Data System (ADS)

Aluminium corrosion in a room temperature molten salt is studied to validate the use of a new kind of electrolyte in a lithium battery. Two solvents have been compared, the room temperature molten salt ethyl-methyl-imidazolium bis(trifluoromethane-sulfonyl)imide (EMI-TFSI), and the liquid organic solvent EC/DMC containing the lithium salt LiTFSI. After confirmation of high aluminium corrosion in the liquid solvent, the results does not show the occurrence of corrosion in the room temperature molten salt.

Garcia, Béatrice; Armand, Michel

72

Influenceof aluminium precursor on physico-chemical properties of aluminium hydroxidesand oxides  

Microsoft Academic Search

The process of hydrolysis of\\u000a aqueous aluminium sulfate was carried on in ammonia medium at 100C and\\u000a for different time intervals (0, 20, 39 or 59 h). The products thus obtained\\u000a were calcined at 550, 900 or 1200C for 2 h with the aim to obtain aluminium\\u000a oxides. The materials were studied with the following methods: thermal analysis,\\u000a IR spectroscopy,

Barbara Pacewska; Olga Kluk-P?osko?ska; D. Szychowski

2007-01-01

73

The origin of acoustic emission during deformation of aluminium and an aluminium-magnesium alloy  

Microsoft Academic Search

The acoustic emission power during deformation of pure aluminium single crystals and polycrystals, and specimens of A1 1·3wt% Mg, has been measured. In pure aluminium the acoustic emission activity increased with grain size to approach the levels of activity from single crystals, whereas the emission activity of the Al 1·3wt% Mg solid solution exhibited a peak at a grain size

C. Scruby; H. Wadley; J. E. Sinclair

1981-01-01

74

Quench-hardening of aluminium and aluminium-magnesium by sub-microscopic defects  

Microsoft Academic Search

Comparison of the effect of ageing on the flow stress of water-quenched and air-cooled aluminium and aluminium-magnesium alloys has clearly demonstrated that the hardening is inversely related to the concentration of visible dislocation loops. Hardening by more highly dispersed vacancy clusters is therefore postulated and the results interpreted in terms of the bowing of moving dislocations pinned by the lattice

D. Hardie; A. D. Michael

1971-01-01

75

Evidence for a Ternary Phase in the Aluminium-Magnesium-Silver System  

Microsoft Academic Search

Polmear and Sargant1 and Polmear2 have recently reported that small silver additions will influence the age-hardening characteristics of aluminium-magnesium alloys. They show, for example1, that the precipitate in a wrought Al-7 wt. per cent Mg alloy is finer and more uniformly dispersed with resultant increase in hardening, on the addition of 0.5 wt. per cent silver, and they suggest that

M. J. Wheeler; G. Blankenburgs; R. W. Staddon

1965-01-01

76

Electrorefining of aluminium scrap from chloride melts  

Microsoft Academic Search

The production of aluminium of primary quality from scrap by electrorefining may become an option of strategic importance. Two important requirements are: (i) substantial energy savings compared to electrowinning, and (ii) easy recycling of alloying elements and molten electrolyte without ecological hazards. The use of molten chloride instead of fluoride electrolytes is preferred as emissions are low, purification of contaminated

V. Schwarz; H. Wendt

1995-01-01

77

Ag-Al-Mg (Silver - Aluminium - Magnesium)  

Microsoft Academic Search

This document is part of Subvolume A1 'Light Metal Systems. Part 1: Selected Systems from Ag-Al-Cu to Al-Cu-Er' of Volume 11 'Ternary Alloy Systems - Phase Diagrams, Crystallographic and Thermodynamic Data critically evaluated by MSIT®' of Landolt-Börnstein - Group IV Physical Chemistry. It provides the data for the ternary system Ag-Al-Mg (Silver - Aluminium - Magnesium).

2004-01-01

78

Visual detection and sequential injection determination of aluminium using a cinnamoyl derivative.  

PubMed

A cinnamoyl derivative, 3-[4-(dimethylamino)cinnamoyl]-4-hydroxy-6-methyl-3,4-2H-pyran-2-one, was used as a ligand for the determination of aluminium. Upon the addition of an acetonitrile solution of the ligand to an aqueous solution containing Al(III) and a buffer solution at pH 8, a marked change in colour from yellow to orange is observed. The colour intensity is proportional to the concentration of Al(III); thus, the 'naked-eye' detection of aluminium is possible. The reaction is also applied for sequential injection determination of aluminium. Beer?s law is obeyed in the range from 0.055 to 0.66mgL(-1) of Al(III). The limit of detection, calculated as three times the standard deviation of the blank test (n=10), was found to be 4?gL(-1) for Al(III). The method was applied for the determination of aluminium in spiked water samples and pharmaceutical preparations. PMID:25435222

Ele?ková, Lenka; Alexovi?, Michal; Kuchár, Juraj; Balogh, Ioseph S; Andruch, Vasil

2015-02-01

79

Use of Propranolol-Magnesium Aluminium Silicate Intercalated Complexes as Drug Reservoirs in Polymeric Matrix Tablets  

PubMed Central

The objective of the present study was to investigate the use of propranolol–magnesium aluminium silicate intercalated complexes as drug reservoirs in hydroxypropylmethylcellulose tablets. The matrix tablets containing the complexes were prepared and characterised with respect to propranolol release and were subsequently compared with those loading propranolol or a propranolol–magnesium aluminium silicate physical mixture. Additionally, the effects of varying viscosity grades of hydroxypropyl methylcellulose, compression pressures and calcium acetate incorporation on the drug release characteristics of the complex-loaded tablets were also examined. The results showed that the complex-loaded tablets have higher tablet hardness than those containing propranolol or a physical mixture. The drug release from the complex-loaded tablets followed a zero-order release kinetic, whereas an anomalous transport was found in the propranolol or physical mixture tablets. The drug release rate of the complex tablet significantly decreased with increasing hydroxypropylmethylcellulose viscosity grade. Increase in the compression pressure caused a decrease in the drug release rate of the tablets. Furthermore, the incorporation of calcium ions could accelerate propranolol release, particularly in acidic medium, because calcium ions could be exchanged with propranolol molecules intercalated in the silicate layers of magnesium aluminium silicate. These findings suggest that propranolol-magnesium aluminium silicate intercalated complexes show strong potential for use as drug reservoirs in matrix tablets intended for modifying drug release. PMID:23626384

Pongjanyakul, T.; Rojtanatanya, S.

2012-01-01

80

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 and a food contaminant with a view to concluding as to safety concerns and to preparing specifications for identity and purity. The first part of the report contains a general discussion of the principles governing the toxicological evaluation of and assessment of dietary exposure to food additives. A summary follows of the Committee's evaluations of technical, toxicological and dietary exposure data for seven food additives (advantame; glucoamylase from Trichoderma reesei expressed in Trichoderma reesei; glycerol ester of gum rosin; glycerol ester of tall oil rosin; glycerol ester of wood rosin; nisin; and octenyl succinic acid modified gum arabic) and an assessment of dietary exposure to cadmium from cocoa and cocoa products. Specifications for the following food additives were revised: annatto extracts (solvent-extracted bixin and solvent-extracted norbixin); Benzoe tonkinensis; food additives containing aluminium and/or silicon; mineral oil (medium viscosity); modified starches; paprika extract; phosphates (analytical methods for the determination of phosphorus and revision of specifications); 3-phytase from Aspergillus niger expressed in Aspergillus niger; potassium aluminium silicate; and potassium aluminium silicate-based pearlescent pigments. Annexed to the report are tables summarizing the Committee's recommendations for dietary exposures to and toxicological evaluations of the food additives and contaminant considered. PMID:24779311

2013-01-01

81

What is the risk of aluminium as a neurotoxin?  

PubMed

Aluminium is neurotoxic. Its free ion, Al(3+) (aq), is highly biologically reactive and uniquely equipped to do damage to essential cellular (neuronal) biochemistry. This unequivocal fact must be the starting point in examining the risk posed by aluminium as a neurotoxin in humans. Aluminium is present in the human brain and it accumulates with age. The most recent research demonstrates that a significant proportion of individuals older than 70 years of age have a potentially pathological accumulation of aluminium somewhere in their brain. What are the symptoms of chronic aluminium intoxication in humans? What if neurodegenerative diseases such as Alzheimer's disease are the manifestation of the risk of aluminium as a neurotoxin? How might such an (outrageous) hypothesis be tested? PMID:24779346

Exley, Christopher

2014-06-01

82

Mechanical Properties of Particulate Reinforced Aluminium Alloy Matrix Composite  

SciTech Connect

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. [Faculty of Engineering, Malikussaleh University of Lhokseumawe, 24300 Aceh (Indonesia); Department of Mechanical and Manufacturing Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400 Serdang, Selangor (Malaysia); Sulaiman, S.; Baharudin, B. T. H. T.; Arifin, M. K. A. [Department of Mechanical and Manufacturing Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400 Serdang, Selangor (Malaysia); Suraya, S.; Vijayaram, T. R.

2011-01-17

83

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.

84

Calmagite as a spectrophotometric reagent for aluminium.  

PubMed

Calmagite is proposed as a sensitive spectrophotometric reagent for aluminium, (570mmu) = 42000. After aqueous phase reaction at pH 8.6, the metal-reagent complex is extracted into chloroform by formation of an ion-association complex with a quaternary ammonium salt. The method is free from interference by common anions, and cationic interferences may be eliminated by the use of cyanide and EDTA as masking agents. PMID:18960299

Woodward, C; Freiser, H

1968-03-01

85

X-ray photoelectron spectroscopy of aluminium-substituted tobermorite  

Microsoft Academic Search

We have synthesised 11-Å tobermorite hydrothermally, both pure and with increasing isomorphic substitution of aluminium for silicon. The samples were analysed by X-ray photoelectron spectroscopy (XPS). Aluminium was found, on the basis of its Al 2p binding energies, to be tetrahedrally coordinated. We observed no changes in Ca\\/(Si+Al) ratio upon aluminium substitution, implying that charge balancing does not occur via

Leon Black; Andreas Stumm; Krassimir Garbev; Peter Stemmermann; Keith R. Hallam; Geoffrey C. Allen

2005-01-01

86

PROPRITS MAGNTIQUES DU GRENAT D'ALUMINIUM ET DE DYSPROSIUM  

E-print Network

357. PROPRI�T�S MAGN�TIQUES DU GRENAT D'ALUMINIUM ET DE DYSPROSIUM II. R�SULTATS EXP�RIMENTAUX de grenat d'aluminium et de dysprosium en fonction soit de l'intensité, soit de l'orientation du of a spherical single crystal of dysprosium aluminium garnet has been measured at T ~ 0.37 °K as a function

Paris-Sud XI, Université de

87

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

88

There is (still) too much aluminium in infant formulas  

PubMed Central

Background Infant formulas are sophisticated milk-based feeds for infants which are used as a substitute for breast milk. Historically they are known to be contaminated by aluminium and in the past this has raised health concerns for exposed infants. We have measured the aluminium content of a number of widely used infant formulas to determine if their contamination by aluminium and consequent issues of child health persists. Methods Samples of ready-made milks and powders used to make milks were prepared by microwave digestion of acid/peroxide mixtures and their aluminium content determined by THGA. Results The concentration of aluminium in ready-made milks varied from ca 176 to 700 ?g/L. The latter concentration was for a milk for preterm infants. The aluminium content of powders used to make milks varied from ca 2.4 to 4.3 ?g/g. The latter content was for a soya-based formula and equated to a ready-to-drink milk concentration of 629 ?g/L. Using the manufacturer's own guidelines of formula consumption the average daily ingestion of aluminium from infant formulas for a child of 6 months varied from ca 200 to 600 ?g of aluminium. Generally ingestion was higher from powdered as compared to ready-made formulas. Conclusions The aluminium content of a range of well known brands of infant formulas remains high and particularly so for a product designed for preterm infants and a soya-based product designed for infants with cow's milk intolerances and allergies. Recent research demonstrating the vulnerability of infants to early exposure to aluminium serves to highlight an urgent need to reduce the aluminium content of infant formulas to as low a level as is practically possible. PMID:20807425

2010-01-01

89

Amazing Addition!!  

NSDL National Science Digital Library

Math can be fun! Practice your addtion facts in one of these amazing games! Go on a mission with math! -- Addition Mission Count your apples! -- Apple Addition Be a math teacher! -- Chalkboard Addition ...

Staggs, Ms.

2008-04-01

90

Electrodeposition of aluminium, aluminium\\/magnesium alloys, and magnesium from organometallic electrolytes  

Microsoft Academic Search

The electrodeposition of aluminum, magnesium, and the combination of these metals from nonaqueous media is discussed. Plating baths for depositing Al\\/Mg alloys or for plating essentially pure Mg were developed. These solutions contain alkali meal fluoride or quaternary ammonium halide\\/aluminium alkyl complexes and dialkyl magnesium dissolved in aromatic hydrocarbons. Alloy deposits over the whole composition range can be plated from

1988-01-01

91

PERFORMANCE OF 2024-T3 ALUMINIUM ADHESIVE BONDED JOINTS  

Microsoft Academic Search

Adhesive bonding of aluminium alloys has been investigated due to its growing importance in aeronautic, aerospace, and automotive industries. This paper examines the influences of two pretreatments, alkaline etching and acid pickling, applied singly or in combination with phosphoric acid anodizing on the mechanical behavior of adhesive bonded 2024-T3 aluminium alloy joints, before and after aging by water immersion. The

I. Pires; L. Quintino; R. M. Miranda

2005-01-01

92

Stochastic simulations of square aluminium tubes subjected to axial loading  

Microsoft Academic Search

Stochastic simulations of square aluminium tubes of 6060 T6 aluminium alloy subjected to axial crushing have been performed and compared to an experimental program carried out previously at SIMLab. The main variables during testing were the extrusion length, the wall thickness of the extrusions and the impact velocity of the impactor. Three different buckling modes were observed: progressive buckling, transition

Ø. Fyllingen; O. S. Hopperstad; M. Langseth

2007-01-01

93

Laser Ablation of Aluminium: Drops and Voids Johannes Roth1  

E-print Network

Laser Ablation of Aluminium: Drops and Voids Johannes Roth1 , Johannes Karlin1 , Christian Ulrich2 for aluminium and a complex metallic alloy. Here we will concentrate on how drops or clusters and voids can part includes the formation of voids in the irradiated region and its temporal evolution. 2 Method

Roth, Johannes

94

Review article Aluminium toxicity in plants: a review  

E-print Network

]. Aluminium toxicity is an important growth-limiting factor for plants in acid soils below pH 5.0 but can, but low concentrations can sometimes increase plant growth or induce other desirable effects [61, 69, 75Review article Aluminium toxicity in plants: a review G.R. ROUTa, S. SAMANTARAYb, P. DASb* a Plant

Paris-Sud XI, Université de

95

Thermal stresses in aluminium alloy die casting dies  

Microsoft Academic Search

The aim of this research is to analyze the influence of Aluminium Alloy die casting parameters, die material, and die geometry on in-service tool life. An innovative immersion testing apparatus is developed, at which Aluminium Alloy die casting is simulated. It enables controlled thermal fatigue cycling. Special specimens with different edge geometry and specimens with maraging steel welds deposited by

Damjan Klob?ar; Janez Tušek

2008-01-01

96

Aluminium salt slag characterization and utilization--a review.  

PubMed

Aluminium salt slag (also known as aluminium salt cake), which is produced by the secondary aluminium industry, is formed during aluminium scrap/dross melting and contains 15-30% aluminium oxide, 30-55% sodium chloride, 15-30% potassium chloride, 5-7% metallic aluminium and impurities (carbides, nitrides, sulphides and phosphides). Depending on the raw mix the amount of salt slag produced per tonne of secondary aluminium ranges from 200 to 500 kg. As salt slag has been classified as toxic and hazardous waste, it should be managed in compliance with the current legislation. Its landfill disposal is forbidden in most of the European countries and it should be recycled and processed in a proper way by taking the environmental impact into consideration. This paper presents a review of the aluminium salt slag chemical and mineralogical characteristics, as well as various processes for metal recovery, recycling of sodium and potassium chlorides content back to the smelting process and preparation of value added products from the final non metallic residue. PMID:22480708

Tsakiridis, P E

2012-05-30

97

Aluminium-magnesium alloys as corrosion resistant coatings for steel  

Microsoft Academic Search

The corrosion behaviour of binary aluminium-magnesium (Al?Mg) alloy coatings deposited on to steel panels using an unbalanced magnetron sputtering technique has been studied. Neutral salt fog tests have shown that the corrosion resistance of sputtered aluminium alloy coatings increases as the magnesium content is raised until an optimum is reached for alloys containing approximately 20 wt% Mg. Increasing the magnesium

K. R. Baldwin; R. I. Bates; R. D. Arnell; C. J. E. Smith

1996-01-01

98

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

99

Ionic fluids in lubrication of aluminium-steel contacts. Surface and tribochemical interactions  

NASA Astrophysics Data System (ADS)

Room-temperature ionic liquids (ILs) are high performance fluids with a wide thermal stability range. They are being studied as new lubricants in a variety of sliding contacts. One of their more interesting tribological applications is that of steel-aluminium lubrication. In this work we study the influence of the lateral alkyl chain length and of the anion on the lubricating ability of six imidazolium ILs, a pyridinium and a phosphonium derivative. For first time, these ILs have been studied as neat lubricants and as 1wt.% base oil additives in variable conditions of velocity, load and temperature in pin-on-disk tests for AISI 52100 steel-ASTM 2011 aluminium contacts. In this work we present the first study of ILs as lubricants under extreme temperature conditions. The tribological performance of ILs has been compared with that of a mineral oil and of a synthetic ester. Under these conditions, ILs show lower friction and wear values than conventional oils at all temperatures. As 1wt.% additives, the conditions of optimum lubrication and the transitions between regimes and lubrication mechanisms have been determined. We have also studied the performance of ILs as 1wt.% additives of the synthetic oil. A relationship between additive polarity and wear index has been established. If the more soluble phosphonium IL additive is used, no friction or wear reduction takes place due to competition between solvation and adsorption processes. Electronic microscopy (SEM), energy dispersive (EDS) and X-ray photoelectron (XPS) spectroscopies have been used to study the wear mechanisms and tribochemical processes that take place in the contact. Finally, we have studied the performance of three aluminium alloys in corrosion and erosion-corrosion tests. In immersion tests with free-water ILs, the aluminium alloy 2011 shows a good resistance to corrosion, but dilution of 1-ethyl, 3-methylimidazolium tetrafluoroborate in water produces the hydrolysis of the anion and the corrosion of the aluminium alloy. In erosion-corrosion tests, although the three alloys show a good corrosion resistance (?0.2 mm/year) their performance is related to the copper content, with higher rates at higher copper percentages. The surfaces have been characterized by SEM, EDS, XPS and X-ray diffraction (XRD).

Jimenez Ballesta, Ana Eva

100

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

101

Composite Ni-Co-fly ash coatings on 5083 aluminium alloy  

NASA Astrophysics Data System (ADS)

Ni-Co-fly ash coatings were deposited on zincate treated 5083 wrought aluminium alloy substrates with the aid of the electrodeposition technique. Structural and chemical characterization of the produced composite coatings was performed with the aid of X-ray diffraction (XRD), scanning electron microscopy (SEM) and electron dispersive X-ray analysis (EDS) techniques. The Ni-Co-fly ash coatings were found to consist of a crystalline Ni-Co solid solution with dispersed fly ash particles. In addition, chemical analysis of the Ni-Co matrix showed that it consisted of 80 wt.% Ni and 20 wt.% Co. The co-deposition of fly ash particles leads to a significant increase of the microhardness of the coating. The corrosion behaviour of the Ni-Co-fly ash/zincate coated aluminium alloy, in a 0.3 M NaCl solution (pH = 3.5), was studied by means of potentiodynamic corrosion experiments.

Panagopoulos, C. N.; Georgiou, E. P.; Tsopani, A.; Piperi, L.

2011-03-01

102

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

103

Deviatoric response of the aluminium alloy, 5083  

NASA Astrophysics Data System (ADS)

Aluminium alloys such as 5083 are established light weight armour materials. As such, the shock response of these materials is of great importance. The shear strength of a material under shock loading provides an insight into its ballistic performance. In this investigation embedded manganin stress gauges have been employed to measure both the longitudinal and lateral components of stress during plate impact experiments over a range of impact stresses. In turn, these results were used to determine the shear strength and to investigate the time dependence of lateral stress behind the shock front to give an indication of material response.

Appleby-Thomas, Gareth; Hazell, Paul; Millett, Jeremy; Bourne, Neil

2009-06-01

104

Aluminium-containing transdermal patches: a risk of burns.  

PubMed

(1) The waterproof outer layer protecting some transdermal patches is composed of aluminium. This creates a risk of burns, especially when the patient is exposed to electric shocks or intense magnetic fields. (2) External electrical shocks delivered by a defibrillator for example can create electrical arcing between the electrode and the aluminium layer of the patch, potentially causing burns. (3) During Magnetic Resonance Imaging (MRI) the aluminium present in these patches, which is not ferromagnetic, creates electrical resistance (by induction), and can sometimes cause second-degree burns. (4) Patients undergoing MRI or defibrillation should first be examined for patches containing aluminium. Such patches can generally be identified by examining the backing, which is shiny and reflects light if aluminium is present. (5) If in doubt it is best to temporarily remove all transdermal patches before MRI or external defibrillation. (6) Packaging of transdermal patches that contain conductive materials should include more explicit warnings. PMID:18092416

2007-12-01

105

Atmospheric plasma torch treatment of aluminium: Improving wettability with silanes  

NASA Astrophysics Data System (ADS)

This study investigates the effect of atmospheric pressure plasma torch (APPT) treatments on the surface of aluminium alloys. The influence of torch-to-sample distance, speed of treatment and ageing time is analyzed in terms of contact angles and surface energy. Results show that APPT treatment strongly increases the surface energy and wettability of aluminium surfaces. This is related to the formation of polar groups, as Fourier transform infrared (FTIR) spectroscopy has confirmed. In all conditions, hydrophobic recovery of aluminium surfaces takes place. Finally, the compatibility of the APPT treated aluminium substrate with ?-methacryloxypropyltrimethoxysilane (MPS) has been evaluated through adhesion work and spread tension, showing that it is possible to achieve a spontaneous wetting process of silane on aluminium.

Díaz-Benito, B.; Velasco, F.

2013-12-01

106

Transmittance Optical Properties Investigation of Aluminium Ions Aqueous Solution  

NASA Astrophysics Data System (ADS)

Aluminium is a silvery-white metal in Group IIIA of the periodic table with atomic number 13, its atomic weight 26.9815. Aluminium is one of the most toxic elements to human body. In aqueous solution, aluminium ions will dissolve as Al3+(aq) under acidic conditions, and Al(OH)4-(aq) under neutral to alkaline condition. Al3+ ions also can further hydrolyse into [Al(H2O)6]3+ ions. The spectroradiometer used in this study was ASD Spectroradiometer (Model FSHH 325-1075) and the light source's wavelength used was 626 nm, 570 nm and 470 nm. Aluminium ions were added to the water by dissolving the aluminium chloride salt with concentration from 50 ?M, 100 ?M, 250 ?M, and 500 ?M. By varying the detecting wavelength, the resulting transmittance signal will be recorded.

Tan, C. H.; MatJafri, M. Z.; Lim, H. S.

2011-03-01

107

Amazing Addition!!  

NSDL National Science Digital Library

I want you to practice your awesome addition skills on the websites below. I know you will do beautifully! Start by going to this website first: Addition Fun!!! Once you finish that website you may continue onto this website: Alien Addition If you have extra time play Around the World Addition: Once you have clicked on the link, click on the button for addition.After that you can choose to play on easy or ...

Bolton, Ms.

2009-04-22

108

Volatilisation and oxidation of aluminium scraps fed into incineration furnaces  

SciTech Connect

Highlights: Black-Right-Pointing-Pointer Aluminium packaging partitioning in MSW incineration residues is evaluated. Black-Right-Pointing-Pointer The amount of aluminium packaging recoverable from the bottom ashes is evaluated. Black-Right-Pointing-Pointer Aluminium packaging oxidation rate in the residues of MSW incineration is evaluated. Black-Right-Pointing-Pointer 80% of aluminium cans, 51% of trays and 27% of foils can be recovered from bottom ashes. - Abstract: Ferrous and non-ferrous metal scraps are increasingly recovered from municipal solid waste incineration bottom ash and used in the production of secondary steel and aluminium. However, during the incineration process, metal scraps contained in the waste undergo volatilisation and oxidation processes, which determine a loss of their recoverable mass. The present paper evaluates the behaviour of different types of aluminium packaging materials in a full-scale waste to energy plant during standard operation. Their partitioning and oxidation level in the residues of the incineration process are evaluated, together with the amount of potentially recoverable aluminium. About 80% of post-consumer cans, 51% of trays and 27% of foils can be recovered through an advanced treatment of bottom ash combined with a melting process in the saline furnace for the production of secondary aluminium. The residual amount of aluminium concentrates in the fly ash or in the fine fraction of the bottom ash and its recovery is virtually impossible using the current eddy current separation technology. The average oxidation levels of the aluminium in the residues of the incineration process is equal to 9.2% for cans, 17.4% for trays and 58.8% for foils. The differences between the tested packaging materials are related to their thickness, mechanical strength and to the alloy.

Biganzoli, Laura, E-mail: laura.biganzoli@mail.polimi.it [Politecnico di Milano, Piazza L. Da Vinci 32, 20133 Milano (Italy); Gorla, Leopoldo; Nessi, Simone; Grosso, Mario [Politecnico di Milano, Piazza L. Da Vinci 32, 20133 Milano (Italy)

2012-12-15

109

Food additives  

PubMed Central

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. The paper concludes with consideration of those circumstances in which the use of additives is (a) justified and (b) unjustified. PMID:4467857

Spencer, Michael

1974-01-01

110

Synergistic effect of halide ions on the corrosion inhibition of aluminium in H 2SO 4 using 2-acetylphenothiazine  

Microsoft Academic Search

The corrosion inhibition of aluminium in H2SO4 in the presence of 2-acetylphenothiazine (2APTZ) at temperature range of 30–60°C was studied using the weight loss and thermometric techniques. The effect of addition of halides (KCl, KBr, KI) is also reported.The inhibition efficiency (I, %) increased with increase in concentration of 2APTZ. The addition of the halides increased the inhibition efficiency to

E. E Ebenso

2003-01-01

111

Study of ac electrical properties of aluminium epoxy composites  

NASA Astrophysics Data System (ADS)

Ac electrical properties of aluminium flakes-epoxy composites were studied as a function of the composition, frequency and temperature. The dielectric constant increased smoothly with an increase in the concentration of aluminium. An increase in the dielectric constant was observed with the temperature as well as with a decrease in the frequency. The observed increase in the values of the dielectric constant with the aluminium concentration was attributed to interfacial polarization. It was found that ac electrical conductivity increases with increasing content of aluminium, temperature and frequency. The observed enhancement in ac conductivity is attributed to the increase in the number of conduction paths created by the aluminium flake contacts in the composite to give a higher electrical conductivity. Also, the activation energy of aluminium flakes-epoxy composites was determined, as well as the values of the dielectric constant. Compared with various theoretical models, Bruggman's formula gives a better fit. The universal power-law model of ac conductivity is observed in epoxy-aluminium composites. The calculated power exponent (about unity) is physically acceptable within this applied model.

Elimat, Z. M.; Zihlif, A. M.; Ragosta, G.

2008-08-01

112

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. PMID:21170257

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

2010-01-01

113

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

2013-07-15

114

Aluminium recovery vs. hydrogen production as resource recovery options for fine MSWI bottom ash fraction.  

PubMed

Waste incineration bottom ash fine fraction contains a significant amount of aluminium, but previous works have shown that current recovery options based on standard on-step Eddy Current Separation (ECS) have limited efficiency. In this paper, we evaluated the improvement in the efficiency of ECS by using an additional step of crushing and sieving. The efficiency of metallic Al recovery was quantified by measuring hydrogen gas production. The ash samples were also tested for total aluminium content with X-ray fluorescence spectroscopy (XRF). As an alternative to material recovery, we also investigated the possibility to convert residual metallic Al into useful energy, promoting H2 gas production by reacting metallic Al with water at high pH. The results show that the total aluminium concentration in the <4 mm bottom ash fraction is on average 8% of the weight of the dry ash, with less than 15% of it being present in the metallic form. Of this latter, only 21% can be potentially recovered with ECS combined with crushing and sieving stages and subsequently recycled. For hydrogen production, using 10MNaOH at 1L/S ratio results in the release of 6-11l of H2 gas for each kilogram of fine dry ash, equivalent to an energy potential of 118 kJ. PMID:23453355

Biganzoli, Laura; Ilyas, Aamir; Praagh, Martijn van; Persson, Kenneth M; Grosso, Mario

2013-05-01

115

Prediction of deformation characteristics of sintered aluminium preforms using neural networks  

NASA Astrophysics Data System (ADS)

Neural networks (NNs) are employed to study the deformation characteristics of sintered aluminium preforms. The proposed NN model has used the measured parameters, namely the load, the aspect ratio and the initial preform fractional density ratio to predict multiple material characteristics, namely the axial stress, the hoop stress, the hydrostatic stress, the axial strain, the hoop strain and the Poisson's ratio. The model is based on a 'four layered NN' with back propagation learning algorithm. The experimental set-up available in the laboratory has been used to get the training data for the sintered aluminium with various preform densities and different aspect ratios (0.50, 0.75 and 1.00) using MoS2 as lubricant. The predicted values from the proposed NN coincide well with the experimental values. In addition, a comparative study between the regression analysis and the NN revealed that the NN can predict the material characteristics of sintered aluminium preform better than regression polynomials within a few per cent error.

Selvakumar, N.; Radha, P.; Narayanasamy, R.; Davidson, M. Joseph

2004-07-01

116

The behaviour of iron and aluminium during the diffusion welding of carbon steel to aluminium  

Microsoft Academic Search

The diffusion welding of carbon steel to aluminium may be achieved when the temperature and compression of the weld metal\\u000a allows diffusion at the interface between both components; the degree of interdiffusion largely determines the quality of\\u000a the welded joint. Such diffusion processes can take place under vacuum. However, in this paper, we report that high quality\\u000a welds can be

M. Kamal Karfoul; Gordon J. Tatlock; Robert T. Murray

2007-01-01

117

The surface tension of liquid pure aluminium and aluminium-magnesium alloy  

Microsoft Academic Search

This paper discusses the results of several experiments designed to further illustrate the recent findings of the present authors according to which, if a virtually leak-fee maximum bubble pressure system is used to measure the surface tension of liquid aluminium, a surface tension around 1100 mJ m-2 is first obtained, decreasing to the oxidized value (around 865 mJ m-2) as

C. Garcia-Cordovilla; E. Louis; A. Pamies

1986-01-01

118

A micro heat exchanger microfabricated from bulk aluminium  

NASA Astrophysics Data System (ADS)

We report a micro heat exchanger microfabricated from a bulk aluminium alloy substrate. The device is comprised of two 18 cm long microchannels, one on each side of an aluminium chip, capped on both sides with a thin self-adhesive polymer film. In spite of a cheap and facile fabrication method, initial experiments with the device show promising results. Area densities from 25000 m?1 to 45000 m?1 have been achieved. Compared to our previous work on aluminium microfluidic devices produced with a similar technology but from a different, less pure alloy, in this study the etched surfaces are significantly smoother, and present less photoresist delamination.

Scotti, G.; Franssila, S.

2014-11-01

119

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

120

Investigation of the possible influence of the absorption of vinpocetine with concomitant application of magnesium-aluminium-hydroxide gel.  

PubMed

The concomitant application of magnesium-aluminium-hydroxide gel does not influence the absorption of vinpocetine (CAS 42971-09-5). The pharmacokinetics of vinpocetine under the influence of a concomitant application of magnesium-aluminium-hydroxide gel was investigated. 18 healthy male volunteers were included in the study. Vinpocetine was administered in the galenic form of a film-coated tablet in a dosage of 20 mg t.i.d. over 10 days. On days 5 and 6 of the study, blood samples were taken at 16 different moments over 24 h and analyzed as to their vinpocetine content. Starting with the 6th day of the study, the patients were administered in addition 1 sachet of an magnesium-aluminium-hydroxide gel 4 times a day. On day 9 of the trial, blood samples were taken again over 24 h. The parameters examined were AUC, Cmin, Cmax, tmax and Mean Residence Time. The results as to these parameters of day 5 were compared with those of day 9. As a further parameter, apovincaminic acid plasma levels were determined. There was no difference as to the vinpocetine amount absorbed with or without concomitant application of magnesium-aluminium-hydroxide gel. Apovincaminic acid plasma levels were lowered by approx. 11% when associated with the antacid. PMID:1810262

Lohmann, A; Grobara, P; Dingler, E

1991-11-01

121

Radiation induced synthesis of powder yttrium aluminium garnet  

NASA Astrophysics Data System (ADS)

Yttrium-aluminium garnet powders were prepared from aqueous solutions containing yttrium nitrate and aluminium chloride or nitrate via irradiation with accelerated electrons or UV light and via consequent calcination of formed solid phase. UV light seems to be more convenient for yttrium-aluminium garnet preparation; both types of irradiation yield crystalline Y 3Al 5O 12 phase after 1 h calcination at 1000 °C in air, but some amounts of yttrium oxide and aluminium oxide were also detected in calcinated solid phase formed under accelerated electrons irradiation. Preliminary radioluminescence and thermoluminescence measurements were performed to further evaluate prepared materials. Intensive radioluminescence typical for Ce 3+ doped structure was observed; thermoluminescence glow curves show distinctive peaks at 135-140 and 240-250 °C.

?uba, Václav; Indrei, Jakub; Mú?ka, Viliam; Nikl, Martin; Beitlerová, Alena; Pospíšil, Milan; Jakubec, Ivo

2011-09-01

122

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)

123

Molecular dynamics simulation of aluminium diffusion in decagonal quasicrystals  

E-print Network

Molecular dynamics simulation of aluminium diffusion in decagonal quasicrystals Stephen Hocker- tigated by molecular dynamics simulations. Results obtained with newly developed EAM potentials are determined with molecular statics simulations. The qualitative behaviour of the dynamics is also confirmed

Gähler, Franz

124

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 two food contaminants, with the aim of deriving tolerable intakes where appropriate and 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 of and assessment of dietary exposure to food additives and contaminants. A summary follows of the Committee's evaluations of technical, toxicological and dietary exposure data for certain food additives (aluminium-containing food additives, Benzoe Tonkinensis, glycerol ester of gum rosin, glycerol ester of tall oil rosin, glycerol ester of wood rosin, octenyl succinic acid modified gum arabic, polydimethyl siloxane, Ponceau 4R, pullulan, pullulanase from Bacillus deromificans expressed in Bacillus licheniformis, Quinoline Yellow and Sunset Yellow FCF) and two food contaminants (cyanogenic glycosides and fumonisins). Specifications for the following food additives were revised: aluminium lakes of colouring matters; beta-apo-8'-carotenal; beta-apo-8'-carotenoic acid ethyl ester; beta-carotene, synthetic; hydroxypropyl methyl cellulose; magnesium silicate, synthetic; modified starches; nitrous oxide; sodium carboxymethyl cellulose; and sucrose monoesters of lauric, palmitic or stearic acid. Annexed to the report are tables summarizing the Committee's recommendations for dietary exposures to and toxicological evaluations of the food additives and contaminants considered. PMID:22519244

2011-01-01

125

An interaction of beta-amyloid with aluminium in vitro.  

PubMed

We have used circular dichroism spectroscopy to confirm that, in a membrane-mimicking solvent, A beta P(1-40) adopts a partially helical conformation and we have demonstrated the loss of this structure in the presence of physiologically relevant concentrations of aluminium. This is the first evidence of a direct biochemical interaction between aluminium and beta-amyloid and may have important implications for the pathogenesis of Alzheimer's disease. PMID:8405368

Exley, C; Price, N C; Kelly, S M; Birchall, J D

1993-06-21

126

Subendocardial infarction in a young survivor of aluminium phosphide poisoning.  

PubMed

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 recovery much earlier. PMID:17623772

Kaushik, Rajeev M; Kaushik, Reshma; Mahajan, Sukhdev K

2007-05-01

127

Aluminium powder metallurgy technology for high-strength applications  

Microsoft Academic Search

A literature survey of aluminium powder metallurgy (PM) for high-strength applications was undertaken. Improvements in aluminium—base alloys made via ingot metallurgy (IM) are reaching the point of diminishing returns. PM offers an alternative technology, capable of producing alloys having improved fatigue, corrosion, and stress-corrosion resistance, as well as improved strength and toughness at room or elevated temperatures. The steps involved

J. R. Pickens

1981-01-01

128

Self-piercing riveting connections using aluminium rivets  

Microsoft Academic Search

The development of the self-piercing riveting (SPR) technology in recent years has broadened the application of the technology in the automobile industry. However, the SPR process currently utilises high-strength steel rivets; and the combination between steel rivets with an aluminium car body makes recycling a challenge. The possibility of replacing a steel self-piercing rivet with an aluminium one has thus

N.-H. Hoang; R. Porcaro; M. Langseth; A.-G. Hanssen

2010-01-01

129

Aging of maraging steel welds during aluminium alloy die casting  

Microsoft Academic Search

The aim of this study is to evaluate precipitation annealing of 18% Ni maraging steel repair welds during aluminium die casting and to predict the prolonged in-service tool life. The emphasis of this study is the influence of post-weld precipitation annealing heat treatment and aluminium die casting thermal cycling on metallurgical and mechanical properties. A series of specimens of 1.2344

D. Klob?ar; J. Tušek; B. Taljat; L. Kosec; M. Pleterski

2008-01-01

130

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

131

A role for cyclic hydroxamates in aluminium resistance in maize?  

PubMed

Hydroxamate siderophores have been found to alleviate Al toxicity in bacteria. In Poaceae plants cyclic hydroxamates, like DIMBOA (2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one) and its derivatives have mostly been studied in relation to either defence against insects or allelopathy. In this study the influence of Al on concentrations of these benzoxazinoids (Bx) in root tips, whole roots and root xylem exudates of Zea mays L. varieties differing in Al resistance was analyzed by HPLC-MS. Aluminium resistant maize variety Sikuani maintained considerably higher Bx levels in root tips than the Al sensitive variety Bakero. In vitro binding of Al to DIMBOA was shown by fluorescence quenching. Addition of DIMBOA to Al-containing nutrient solution protected the sensitive maize against Al toxicity as shown by bioassays using callose and haematoxylin staining of root tips as stress indicators. This is the first study showing that Bx can detoxify Al in solution. Tissue analysis data provide first, circumstantial, support for a role of Bx in defence against Al toxicity also in planta. PMID:16054220

Poschenrieder, Charlotte; Tolrà, Roser P; Barceló, Juan

2005-09-01

132

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

133

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

134

Fuel additive  

SciTech Connect

A novel nonacidic fuel additive which is soluable in gasoline, diesel fuels and other liquid aliphatic hydrocarbons, and which comprises the product produced by mixing ketone peroxides, ketones, a Group III metal, an alcohol, and borontrifloride, or liquid cobalt, or a chlorobenzine. The fuel additive further comprises a ketone solvent, said ketones preferrably being methyl etyhl ketones and their peroxides and solvents. The fuel additive of the present invention, serves to increase power output, lower the ignition point of the carrier fuel, increase mileage, and, especially when used with diesel, reduces the effect of cold temperatures on the viscosity, turbidity, and color of the diesel fuel to temperatures as severe as-40/sup 0/ C.

Osgood, G. L.; Reinhard, G. G.

1984-11-13

135

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

136

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

137

Flow and fracture characteristics of aluminium alloy AA5083–H116 as function of strain rate, temperature and triaxiality  

Microsoft Academic Search

This paper presents a part of an on-going study of light-weight shelters made of aluminium alloy AA5083–H116. A necessary prerequisite for numerical simulations of impact behaviour of such shelters is a calibrated numerical model. Slightly modified versions of the two Johnson–Cook models describing flow stress and fracture strain are applied. In addition to ordinary quasistatic tests with smooth specimens, these

Arild H. Clausen; Tore Børvik; Odd S. Hopperstad; Ahmed Benallal

2004-01-01

138

Chromosomal location of PCR fragments as a source of DNA markers linked to aluminium tolerance genes in rye  

Microsoft Academic Search

To identify and locate rye DNA sequences homologous to three wheat c-DNAs (wali1, wali2 and wali5) whose expression is induced by aluminium (Al) stress, we designed three pairs of specific primers. They were used in the\\u000a amplification of genomic DNA from wheat-rye disomic addition lines. The wali2 pair of primers amplified a 878-bp rye DNA fragment (rali2) located on chromosomes

F. J. Gallego; E. López-Solanilla; A. M. Figueiras; C. Benito

1998-01-01

139

Determination of aluminium with 8-hydroxyquinoline-5-sulfonic acid in presence of a cationic surfactant by first and second derivative synchronous fluorimetry  

SciTech Connect

An analytical method has been developed for the fluorimetric determination of nanogram amounts of aluminium in solution. The method is based on the reaction of aluminium with 8-hydroxyquinoline-5-sulfonic acid presence of hexadeciltrimethylammonium bromide as a surfactant agent. Synchronous scanned first and second derivative fluorimetry has been employed to increase the sensitivity of the method. The influence of reaction variables as well as instrumental parameters is discussed. The interference of various foreign ions has also been examined and in some cases eliminated or reduced by addition of 1,10-phenanthroline.

Salinas, F.; de la Pena, A.; Duran, M.S.

1988-08-01

140

Phosphazene additives  

DOEpatents

An additive comprising a phosphazene compound that has at least two reactive functional groups and at least one capping functional group bonded to phosphorus atoms of the phosphazene compound. One of the at least two reactive functional groups is configured to react with cellulose and the other of the at least two reactive functional groups is configured to react with a resin, such as an amine resin of a polycarboxylic acid resin. The at least one capping functional group is selected from the group consisting of a short chain ether group, an alkoxy group, or an aryloxy group. Also disclosed are an additive-resin admixture, a method of treating a wood product, and a wood product.

Harrup, Mason K; Rollins, Harry W

2013-11-26

141

Potlining Additives  

SciTech Connect

In this project, a concept to improve the performance of aluminum production cells by introducing potlining additives was examined and tested. Boron oxide was added to cathode blocks, and titanium was dissolved in the metal pool; this resulted in the formation of titanium diboride and caused the molten aluminum to wet the carbonaceous cathode surface. Such wetting reportedly leads to operational improvements and extended cell life. In addition, boron oxide suppresses cyanide formation. This final report presents and discusses the results of this project. Substantial economic benefits for the practical implementation of the technology are projected, especially for modern cells with graphitized blocks. For example, with an energy savings of about 5% and an increase in pot life from 1500 to 2500 days, a cost savings of $ 0.023 per pound of aluminum produced is projected for a 200 kA pot.

Rudolf Keller

2004-08-10

142

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

143

Corrosion of aluminium metal in OPC- and CAC-based cement matrices  

SciTech Connect

Corrosion of aluminium metal in ordinary Portland cement (OPC) based pastes produces hydrogen gas and expansive reaction products causing problems for the encapsulation of aluminium containing nuclear wastes. Although corrosion of aluminium in cements has been long known, the extent of aluminium corrosion in the cement matrices and effects of such reaction on the cement phases are not well established. The present study investigates the corrosion reaction of aluminium in OPC, OPC-blast furnace slag (BFS) and calcium aluminate cement (CAC) based systems. The total amount of aluminium able to corrode in an OPC and 4:1 BFS:OPC system was determined, and the correlation between the amount of calcium hydroxide in the system and the reaction of aluminium obtained. It was also shown that a CAC-based system could offer a potential matrix to incorporate aluminium metal with a further reduction of pH by introduction of phosphate, producing a calcium phosphate cement.

Kinoshita, Hajime, E-mail: h.kinoshita@sheffield.ac.uk [Department of Materials Science and Engineering, The University of Sheffield, Mappin Street, Sheffield, S1 3JD (United Kingdom)] [Department of Materials Science and Engineering, The University of Sheffield, Mappin Street, Sheffield, S1 3JD (United Kingdom); Swift, Paul; Utton, Claire [Department of Materials Science and Engineering, The University of Sheffield, Mappin Street, Sheffield, S1 3JD (United Kingdom)] [Department of Materials Science and Engineering, The University of Sheffield, Mappin Street, Sheffield, S1 3JD (United Kingdom); Carro-Mateo, Beatriz [The Public University of Navarra, C/Esquíroz, 30 trasera, Pamplona 31007 (Spain)] [The Public University of Navarra, C/Esquíroz, 30 trasera, Pamplona 31007 (Spain); Marchand, Geraldine [The National Institute of Applied Sciences (INSA) Lyon, 20 Avenue Albert Einstein 69621 Villeurbanne Cedex (France)] [The National Institute of Applied Sciences (INSA) Lyon, 20 Avenue Albert Einstein 69621 Villeurbanne Cedex (France); Collier, Nick [National Nuclear Laboratory, Chadwick House, Birchwood Park, Warrington, WA3 6AE (United Kingdom)] [National Nuclear Laboratory, Chadwick House, Birchwood Park, Warrington, WA3 6AE (United Kingdom); Milestone, Neil [Industrial Research Ltd., 69 Gracefield Road, Lower Hutt, 5040 (New Zealand)] [Industrial Research Ltd., 69 Gracefield Road, Lower Hutt, 5040 (New Zealand)

2013-08-15

144

Effects on the nervous system in different groups of workers exposed to aluminium  

PubMed Central

OBJECTIVE—To investigate possible neurotoxic effects in groups of aluminium pot room and foundry workers, aluminium welders, and a small group of workers exposed to aluminium in the production of flake powder.?METHODS—Exposure to aluminium was evaluated with aluminium concentrations in blood and urine as well as a questionnaire. The groups exposed to aluminium were compared with a group of mild steel welders. Neurotoxic effects were studied with mood and symptom questionnaires and several psychological and neurophysiological tests.?RESULTS—The pot room and foundry workers showed very low aluminium uptake as their aluminium concentrations in blood and urine were close to normal, and no effects on the nervous system were detected. The group of workers exposed to flake powder had high concentrations of aluminium in blood and urine, even higher than those of the aluminium welders. However, aluminium could not be shown to affect the functioning of the nervous system in flake powder producers. Although significant effects could not be shown in the present analysis of the data on welders, the performance of the welders exposed to high concentrations of aluminium was affected according to the analyses in the original paper from this group.?CONCLUSIONS—For the pot room and foundry workers no effects related to the exposure to aluminium could be found. For the group of flake powder producers exposed for a short term no effects on the nervous systems were evident despite high levels of exposure. Due to the high concentrations of aluminium in the biological samples of this group, measures to reduce the exposure to aluminium are recommended, as effects on the central nervous system might develop after protracted exposures. However, this assumption needs to be verified in further studies.???Keywords: aluminium; workers; nervous system PMID:11404450

Iregren, A; Sjogren, B; Gustafsson, K; Hagman, M; Nylen, L; Frech, W; Andersson, M; Ljunggren, K; Wennberg, A

2001-01-01

145

Thickness-Dependent Mechanical Behaviour of Aluminium-Coated Polyethylene Terephthalate (PET) Films  

Microsoft Academic Search

Mechanical behaviour of aluminium-coated PET films has been investigated through Dynamic Mechanical Analyser. Aluminium is coated on PET substrate by vacuum thermal evaporation method. As thickness of aluminium coating increases from 150 nm to 350 nm, tensile strength decreases from 108.88 MPa to 99.25 MPa. This mechanical behaviour is correlated with microstructure and its evolution with the thickness of aluminium coating. Al-PET film consists

Sandhya Gupta; Manasvi Dixit; Mahesh Baboo; Kananbala Sharma; N. S. Saxena

2009-01-01

146

Stimulation of eryptosis by aluminium ions  

SciTech Connect

Aluminium salts are utilized to impede intestinal phosphate absorption in chronic renal failure. Toxic side effects include anemia, which could result from impaired formation or accelerated clearance of circulating erythrocytes. Erythrocytes may be cleared secondary to suicidal erythrocyte death or eryptosis, which is characterized by cell shrinkage and exposure of phosphatidylserine (PS) at the erythrocyte surface. As macrophages are equipped with PS receptors, they bind, engulf and degrade PS-exposing cells. The present experiments have been performed to explore whether Al{sup 3+} ions trigger eryptosis. The PS exposure was estimated from annexin binding and cell volume from forward scatter in FACS analysis. Exposure to Al{sup 3+} ions ({>=} 10 {mu}M Al{sup 3+} for 24 h) indeed significantly increased annexin binding, an effect paralleled by decrease of forward scatter at higher concentrations ({>=} 30 {mu}M Al{sup 3+}). According to Fluo3 fluorescence Al{sup 3+} ions ({>=} 30 {mu}M for 3 h) increased cytosolic Ca{sup 2+} activity. Al{sup 3+} ions ({>=} 10 {mu}M for 24 h) further decreased cytosolic ATP concentrations. Energy depletion by removal of glucose similarly triggered annexin binding, an effect not further enhanced by Al{sup 3+} ions. The eryptosis was paralleled by release of hemoglobin, pointing to loss of cell membrane integrity. In conclusion, Al{sup 3+} ions decrease cytosolic ATP leading to activation of Ca{sup 2+}-permeable cation channels, Ca{sup 2+} entry, stimulation of cell membrane scrambling and cell shrinkage. Moreover, Al{sup 3+} ions lead to loss of cellular hemoglobin, a feature of hemolysis. Both effects are expected to decrease the life span of circulating erythrocytes and presumably contribute to the development of anemia during Al{sup 3+} intoxication.

Niemoeller, Olivier M. [Department of Physiology, University of Tuebingen (Germany); Kiedaisch, Valentin [Department of Physiology, University of Tuebingen (Germany); Dreischer, Peter [Department of Physiology, University of Tuebingen (Germany); Wieder, Thomas [Department of Physiology, University of Tuebingen (Germany); Lang, Florian [Department of Physiology, University of Tuebingen (Germany)]. E-mail: florian.lang@uni-tuebingen.de

2006-12-01

147

Reliability determination of aluminium electrolytic capacitors by the mean of various methods.  

E-print Network

Reliability determination of aluminium electrolytic capacitors by the mean of various methods-strength concept. Large aluminium electrolytic capacitors are taken here in example in the context load-strength concept. We take as example aluminium electrolytic capacitors. These components are used

Paris-Sud XI, Université de

148

Fatigue of aluminium-lithium alloys K. T. Venkateswara Rao and R. O. Ritchie  

E-print Network

Fatigue of aluminium-lithium alloys K. T. Venkateswara Rao and R. O. Ritchie Aluminium in commercial and military aircraft. In this review, the cyclic fatigue strength and fatigue crack propagation. Compared with traditional aerospace aluminium alloys, results on the fatigue of binary AI-Li, experimental

Ritchie, Robert

149

JOURNAL OF MATERIALS SCIENCE 40 (2005) 4005 4008 The multiaxial yield behaviour of an aluminium  

E-print Network

powders of titanium hydride (TiH2) with aluminium and the alloying elements magnesium and silicon, Cambridge CB2 1PZ (UK) E-mail: naf1@eng.cam.ac.uk The multi-axial yield behaviour of the aluminium alloyJOURNAL OF MATERIALS SCIENCE 40 (2005) 4005­ 4008 The multiaxial yield behaviour of an aluminium

Fleck, Norman A.

150

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

151

Aluminium in an ocean GCM: sources and sinks  

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 as well as from sediments by sediment remobilisation. 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. Comparison with observations shows that some processes might be missing in the model, among which the biological incorporation of aluminium into diatoms.

van Hulten, Marco; Sterl, Andreas; Tagliabue, Alessandro; Gehlen, Marion; Dutay, Jean-Claude; Middag, Rob; de Baar, Hein

2013-04-01

152

Characterisation of the anodic layers formed on 2024 aluminium alloy, in tetraborate electrolyte containing molybdate ions  

NASA Astrophysics Data System (ADS)

Anodic layer growth on 2024 aluminium alloy at 70 °C, under 40 V, during 60 min, in 50 g L -1 di-sodium tetraborate solution containing di-sodium molybdate from 0.1 to 0.5 M (pH 10) is examined. Anodising behaviours strongly depend on additive concentration. Development of anodic films is favoured with weak molybdate additions (<0.3-0.4 M). The film thicknesses increase and the porosity of anodic layers decreases. Molybdenum (+VI), detected by X-ray photoelectron spectroscopy (XPS) analysis, is present in the anodic films and the Mo incorporation, studied by energy dispersive spectroscopy (EDS) analysis, increases with molybdate concentration. However, for high molybdate concentrations (>0.4 M), anodising behaviour becomes complex with the formation of a blue molybdenum oxide at the cathode. The growth of aluminium oxide is hindered. As the anodic layers are thinner, the Mo(+VI) incorporation significantly decreases. These two configurations implicate different corrosion performances in 5% sodium chloride solution at 35 °C. As the alkaline anodic layer formed with 0.3 M molybdate species is the thickest and the Mo incorporation is the more pronounced, its corrosion resistance is the highest. The effect of morphology and composition of anodic films on pitting corrosion is also discussed.

Moutarlier, V.; Pelletier, S.; Lallemand, F.; Gigandet, M. P.; Mekhalif, Z.

2005-12-01

153

Characterisation of Ga-coated and Ga-brazed aluminium  

SciTech Connect

This work is devoted to the brazing of aluminium using liquid gallium. Gallium was deposited on aluminium samples at {approx} 50 Degree-Sign C using a liquid gallium 'polishing' technique. Brazing was undertaken for 30 min at 500 Degree-Sign C in air. EDS (Energy Dispersive X-ray Spectroscopy) and AES (Auger Electron Spectroscopy) characterisation of Ga-coated samples has shown that the Ga surface layer thickness is of ten (or a few tens of) nanometres. Furthermore, aluminium oxide layer (Al{sub 2}O{sub 3}) was shown to be 'descaled' during Ga deposition, which ensures good conditions for further brazing. Cross-section examination of Ga-coated samples shows that liquid gallium penetrates into the aluminium grain boundaries during deposition. The thickness of the grain boundary gallium film was measured using an original EDS technique and is found to be of a few tens of nanometres. The depth of gallium grain boundary penetration is about 300 {mu}m at the deposition temperature. The fracture stress of the brazed joints was measured from tensile tests and was determined to be 33 MPa. Cross-section examination of brazed joints shows that gallium has fully dissolved into the bulk and that the joint is really autogenous. - Highlights: Black-Right-Pointing-Pointer Aluminium can be brazed using liquid gallium deposited by a 'polishing' technique. Black-Right-Pointing-Pointer The aluminium oxide layer is 'descaled' during liquid Ga 'polishing' deposition. Black-Right-Pointing-Pointer EDS can be used for determination of surface and grain boundary Ga film thickness. Black-Right-Pointing-Pointer The surface and grain boundary Ga film thickness is of a few tens of nm. Black-Right-Pointing-Pointer Surface and grain boundary gallium dissolves in the bulk during brazing.

Ferchaud, E. [Universite de Nantes, Polytech'Nantes, Laboratoire Genie des Materiaux et Procedes Associes, Rue Christian Pauc, 44306 Nantes Cedex 3 (France); Christien, F., E-mail: frederic.christien@univ-nantes.fr [Universite de Nantes, Polytech'Nantes, Laboratoire Genie des Materiaux et Procedes Associes, Rue Christian Pauc, 44306 Nantes Cedex 3 (France); Barnier, V. [Ecole Nationale Superieure des Mines, MPI, CNRS UMR5146, Centre SMS, 158 Cours Fauriel, 42023 Saint Etienne (France); Paillard, P. [Universite de Nantes, Polytech'Nantes, Laboratoire Genie des Materiaux et Procedes Associes, Rue Christian Pauc, 44306 Nantes Cedex 3 (France)

2012-05-15

154

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

2009-10-01

155

The solubility of aluminium in Pb-17Li  

NASA Astrophysics Data System (ADS)

The saturation solubility of aluminium in Pb-17Li has been measured over the temperature range envisaged for a Pb-17Li tritium breeder/coolant blanket for use in a fusion reactor. The solubility is given by the equation log10S( wppm) = 6.249 - 2784.9/ T( K) for T = 525 - 813 K.The results are compared to literature values for the solubility of aluminium in pure lead and show good agreement. A value for the enthalpy of solution of + 55.8 kJ mol -1 has been calculated.

Barker, Marten G.; Capaldi, Michael J.

1994-06-01

156

Aluminium accumulation by some cerrado native species of central Brazil  

Microsoft Academic Search

Summary  Among thirty species belonging to seventeen families common in the cerrado region of central Brazil, eight species belonging\\u000a to three families were found to accumulate aluminium in their leaves in considerable amounts (4,310 to 14,120 mg\\/kg on dry\\u000a weight basis) from a dark red latossol which is strongly-acid and low in available nutrient cations. The aluminium-accumulating\\u000a species areMiconia ferruginata (DC.)

M. Haridasan

1982-01-01

157

Effect of Titanium Carbide particle addition in the aluminium composite on EDM process parameters  

Microsoft Academic Search

Machining of hard materials such as metal matrix composites (Al\\/TiC) to a high degree of accuracy and surface finish is difficult. Electrical discharge machining (EDM) is an important process for machining difficult-to-machine materials like metal matrix composites. EDM is an effective tool in shaping such difficult-to-machine materials. The objective of this work is to investigate the effect of current (C),

Velusamy Senthilkumar; Bidwai Uday Omprakash

2011-01-01

158

Gypsum addition to soils contaminated by red mud: Implications for aluminium, arsenic, molybdenum and vanadium solubility.  

E-print Network

) vanadium (V) have de- creased by about 60% over this 30 year period. Consistency in the ratios of nss SO= 4, 1980; Rahn and McCaffrey, 1980). The ratio of non-crustal (nc) manganese (Mn) to nc vanadium (V

Burke, Ian

159

Sources and speciation of aluminium and silicon in natural waters.  

PubMed

The aluminosilicate minerals of igneous and metamorphic rocks are mostly unstable in earth-surface weathering conditions. In the tropics and subtropics, they are transformed to stable end-products (crystalline clay minerals, oxides and hydroxides) that largely conserve aluminium and iron. In noncalcareous soils in temperature and boreal climates, aluminium can be markedly mobile, and is precipitated as metastable products that include hydrous aluminosilicates, hydroxyaluminium polymers in or on 2:1 layer silicates, and complexes with soil organic matter. The aluminosilicate precipitates formed at pH less than 5.5 have structures related to imogolite, a unidimensional crystal in the form of a tube of 2.3 nm outer diameter. These metastable precipitates, both organic and inorganic, are readily remobilized on further acidification, and can release aluminium into streams if the solutions are not neutralized in the subsoil. Three classes of soluble aluminium species in natural waters have been distinguished by their rate of reaction with complexing reagents, and their rate of adsorption on cation-exchange columns. These are: (a) unreactive, acid-soluble, Al, (b) labile monomeric Al, and (c) non-liable monomeric Al. Group (b) includes simple inorganic species (e.g. Al3+, AlOH2+, AlF2+), and group (c) is thought to include organic complexes. In contrast, silicon occurs dominantly as Si(OH)4 monomers in natural water. Its metastable precipitates include hydrous aluminosilicates and biogenic opal. PMID:3743232

Farmer, V C

1986-01-01

160

Line formation of neutral aluminium in the Sun  

Microsoft Academic Search

We investigate the formation of neutral aluminium lines in the solar photosphere using an atomic model containing 58 levels plus the ground state of Al II connected via radiative and collisional interaction. Synthetic line flux and intensity profiles are compared with the solar spectrum to study the relevant kinetic processes and their influence on level populations and line profiles. For

D. Baumueller; T. Gehren

1996-01-01

161

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

162

A review on friction stir welding for aluminium alloys  

Microsoft Academic Search

Friction stir welding is a solid state welding process which involves joining similar or dissimilar metals using a rotating tool. Tool geometry and traverse speed and rotating speed of motion of the tool, tool axial force and tilt angle are some of the variables in this process. Many materials like Aluminium alloy 2000, 6000 and 7000 series have been joined

M. Sivashanmugam; S. Ravikumar; T. Kumar; V. S. Rao; D. Muruganandam

2010-01-01

163

An Aluminium Hydroxide Gel Adsorbed Inactivated Egg Drop Syndrome Vaccine  

Microsoft Academic Search

An inactivated vaccine was prepared from local isolates of egg drop syndrome (EDS) virus using aluminum hydroxide as an adjuvant. A total of 30 commercial layers at the age of 16 weeks were procured and divided in to two groups, A and B having 20 and 10 birds, respectively. The birds of group A were vaccinated with 0.5ml aluminium hydroxide

2004-01-01

164

INTERGRANULAR CORROSION OF SINGLE PHASE ALUMINIUM AS A PITTING PHENOMENON  

E-print Network

INTERGRANULAR CORROSION OF SINGLE PHASE ALUMINIUM AS A PITTING PHENOMENON M. METZGER Department of pitting corrosion in sulfuric acid containing sodium chloride were described. Intergranular fissuring in producing this type of attack. The intergranular corrosion phenomena which are exhibited by high purity

Paris-Sud XI, Université de

165

PERCOLATION AND SUPERCONDUCTIVITY IN ION-IMPLANTED ALUMINIUM FILMS (*)  

E-print Network

L-435 PERCOLATION AND SUPERCONDUCTIVITY IN ION-IMPLANTED ALUMINIUM FILMS (*) F. MEUNIER and P of Si and Ge in Al thin films at 8 K produces alloys exhibiting enhanced superconducting transition in the superconducting transition temperature Tc of several such alloys [2], [5], [6] : Josephson tunnelling

Boyer, Edmond

166

Retention of ferrite in AluminiumAlloyed TRIPassisted steels  

E-print Network

Retention of ­ferrite in Aluminium­Alloyed TRIP­assisted steels Young Joo Choi1, Dong­Woo Suh1 of excess ­ferrite in the microstructure observed at ambient temperature. These provided valuable information for comparison against kinetic simulations which prove that the excess ferrite cannot

Cambridge, University of

167

Cold forming of aluminium—state of the art  

Microsoft Academic Search

The ongoing development of cold forging technology has been manifested lately by the increasing application of components in cold forged aluminium alloys. Applying precipitation hardening alloys components with great strength\\/weight ratio can be produced with a strength comparable to that of unalloyed steel. After description of the different types of alloys and their individual properties and applications, the special requirements

N. Bay

1997-01-01

168

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

169

Applicability of highly reflective aluminium coil for solar concentrators  

Microsoft Academic Search

Because of their manufacturing flexibility and their low costs, mirrors based on anodized or coated sheet aluminium are a promising alternative as primary or secondary concentrators in a number of solar energy applications. They offer solar weighted reflectances of 88–91%, good mechanical properties and are easy to recycle. However, problems occur due to their limited corrosion resistance. Therefore, prior to

Thomas Fend; Gary Jorgensen; Harald Küster

2000-01-01

170

Effects of silicon on the toxicity of aluminium to soybean  

Microsoft Academic Search

The effects of soluble silicon (Si) on the toxicity of aluminium (Al) to soybean roots were investigated in solution culture. A weak nutrient solution which included a low concentration of phosphorus (P) was shown to be necessary to allow the full expression of Al toxicity. As solution pH decreased below 6, reductions in root growth in the presence of Al

A. D. Baylis; C. Gragopoulou; K. J. Davidson; J. D. Birchall

1994-01-01

171

Microstructure development during the deformation of aluminium-magnesium alloys  

Microsoft Academic Search

The conditions for serrated yielding in aluminium-magnesium alloys in temperature\\/strain rate space are reported. The microstructures of samples deformed just within and just outside the serrated regime are described. The differences in structure seen are relatively minor and do not seem to reflect the markedly different deformation behaviour. The conclusion is drawn that the deformed microstructures are formed, in part,

B. A. Parker; JangHo Lim

1996-01-01

172

Enhanced Age-hardening in Aluminium-Magnesium Alloys  

Microsoft Academic Search

ALTHOUGH the solubility of magnesium in aluminium is as high as 16.8 per cent (alloy contents are expressed as atomic percentages) at 450° C (ref. 1), and decreases to an estimated value of 1 per cent at room temperature, the alloys show an abnormally small response to age-hardening. Furthermore, there is no evidence to indicate that the ageing characteristics of

I. J. Polmear; K. R. Sargant

1963-01-01

173

ABRASIVE WEAR OF ALUMINIUM-MAGNESIUM ALLOYS AT VARIOUS TEMPERATURES  

Microsoft Academic Search

The abrasive wear and hot'' hardness of alloys of aluminium and ; magnesium of various concentrations was investigated at various temperatures. ; Specimens, cast into a chill mold and subsequently annealed, were studied. They ; had the following concentrationsn: 0, 1, nesium, the remainder being technically ; pure aluminum. The following temperatures were selected for testing: specimen of ; 5

V. N. Kashcheyev; L. N. Voytsekhovksaya

1959-01-01

174

High strain rate compressive behaviour of aluminium alloy foams  

Microsoft Academic Search

The high strain rate compressive behaviour of two cellular aluminium alloys (Alulight and Duocel) has been investigated using the split Hopkinson pressure bar and direct impact tests. It is found that the dynamic behaviour of these foams is very similar to their quasi-static behaviour. The plateau stress is almost insensitive to strain rate, for strain rates ?? up to 5000s?1.

V. S. Deshpande; N. A. Fleck

2000-01-01

175

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

NASA Astrophysics Data System (ADS)

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 silicate electrolyte. Zirconia was also present in cellular microstructures of the main alumina-rich coating layers, suggesting melting at >1710 °C and subsequent solidification. The coatings frequently contained tetragonal zirconia in addition to monoclinic zirconia, with the presence of zirconia also affecting the proportions of ?- and ?-alumina in favour of the former phase.

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

2008-12-01

176

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. PMID:23509687

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

2013-01-01

177

A separation method to overcome the interference of aluminium on zinc determination by inductively coupled plasma atomic emission spectroscopy  

NASA Astrophysics Data System (ADS)

The use of polyurethane foam (PUF) to separate zinc from large amounts of aluminium and its determination by inductively coupled plasma atomic emission spectroscopy technique (ICP-AES) in aluminium matrices is described. The proposed method is based on the solid-phase extraction of the zinc(II) cation as a thiocyanate complex. Parameters such as effect of pH on zinc sorption, zinc desorption from the foam and analytical features of the procedure were studied. Results showed that the zinc(II) cation within the range from 0.02 to 65.0 ?g in 0.2 mol l -1 thiocyanate solution and pH range from 1.0 to 4.0, could be quantitatively extracted by 0.1 g of PUF. The precision of the method was calculated as the relative standard deviation from a series of seven measurements. It was 3.9% for 1.0 ?g of zinc in a volume solution of 50 ml. The proposed procedure was used for zinc determination in both aluminium alloys and salts with zinc concentration in the range from 50 to 300 ?g g -1. A standard addition technique was used and achieved results showing that this procedure has good accuracy and precision.

de Jesus, Djane S.; das Graças Korn, Maria; Ferreira, Sérgio L. C.; Carvalho, Marcelo S.

2000-04-01

178

Effect of aluminium hydroxide on serum ionised calcium, immunoreactive parathyroid hormone, and aluminium in chronic renal failure.  

PubMed

According to the Bricker-Slatopolsky theory, secretion of parathyroid hormone (PTH) is switched on in chronic renal failure by hypocalcaemia due to phosphate retention. In an attempt to reverse this process 20 patients in preterminal renal failure (plasma creatinine 569 +/- 195 mumol/l) were given aluminium hydroxide, 3.8 g daily. They were studied for four weeks and all measurements were made at the start and weekly, except measurements of serum aluminium concentration, which were made at the start and at the end of the fourth week. Mean serum phosphate fell from 1.89 to 1.47 mmol/l (5.9 to 4.6 mg/100), mean serum calcium rose from 2.07 to 2.24 mmol/l (8.3 to 9.0 mg/100 ml), and serum ionised calcium rose from 1.07 to 1.20 mmol/l (4.3 to 4.8 mg/100 ml), but serum immunoreactive PTH did not fall. Thirteen patients had initial serum immunoreactive PTH concentrations at or near to normal and 11 were taking beta-blockers but even in those with neither explanation, PTH concentrations did not fall. Serum aluminium concentrations rose from 0.4 to 1.02 mumol/l (10.9 to 27.4 microgram/l). Aluminium hydroxide corrects serum phosphate, total calcium, and ionised calcium at the price of a rise in serum aluminium concentration; in this study it did not affect serum immunoreactive PTH. The Bricker-Slatopolsky theory still needs verification in studies of patients with chronic renal failure. PMID:6802224

Biswas, C K; Arze, R S; Ramos, J M; Ward, M K; Dewar, J H; Kerr, D N; Kenward, D H

1982-03-13

179

A histological study of toxic effects of aluminium sulfate on rat hippocampus.  

PubMed

Abstract Aluminium has toxic effects on many organ systems of the human body. Aluminium toxicity also is a factor in many neurodegenerative diseases. We investigated changes in numbers of hippocampal neurons in rats exposed to aluminium using an optical fractionator and we investigated aluminium-induced apoptosis using the transferase mediated dUTP nick end labeling (TUNEL) assay. Twenty-four female rats were divided equally into control, sham and aluminium-exposed groups. The control group received no treatment. The two treatment groups were injected intraperitoneally with 1 ml 0.9% saline without (sham) and with 3 mg/ml aluminium sulfate every day for two weeks. Following the treatments, the brains were removed, the left hemisphere was used for hippocampal neuron counting using an optical fractionator and the right hemisphere was investigated using hippocampal TUNEL assay to determine the apoptotic index. The number of neurons in the stratum pyramidale of the hippocampus was significantly less in the aluminium group than in the control and sham groups; there was no significant difference between the control and sham groups. The apoptotic index also was significantly higher in the aluminium group than in the other two groups. We quantified the toxic effects of aluminium on the rat hippocampus and determined that apoptosis was the mechanism of aluminium-induced neuron death in the hippocampus. PMID:25314162

Çabu?, N; O?uz, Eo; Tufan, Aç; Ad?güzel, E

2015-02-01

180

Pretreatment of aluminium: topography, surface chemistry and adhesive bond durability  

Microsoft Academic Search

This paper reports on work in which bonded joints between a clad aluminium alloy (L165, comprising Cu 4.4%, Mg 0.5%, Si 0.8%, Mn 0.8%), with different pretreatments, and an epoxy resin (Ciba-Geigy's Redux 312\\/5) have been examined. The datum for comparison of the pretreatments is the Boeing phosphoric acid anodization (BAC 5555). Other treatments include sulfuric acid anodizing in combination

R. P. Digby; D. E. Packham

1995-01-01

181

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

182

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

183

Genetic control of aluminium tolerance in rye (Secale cereale L.)  

Microsoft Academic Search

Aluminium (Al) tolerance in roots of two cultivars (“Ail?s” and “JNK”) and two inbred lines (“Riodeva” and “Pool”) of rye\\u000a was studied using intact roots immersed in a nutrient solution at a controlled pH and temperature. Both the cultivars and\\u000a the inbred lines analysed showed high Al tolerance, this character being under multigenic control. The inbred line “Riodeva”\\u000a was sensitive

F. J. Gallego; C. Benito

1997-01-01

184

Role of chloride ions in the anodic oxidation of aluminium  

Microsoft Academic Search

Aluminium surfaces are oxidised to form Al2O3 in a freshly prepared anodising bath and in a bath deliberately contaminated with Cl- ions at concentrations ranging from 35 mu g ml-1 to 200 mu g ml-1. It is observed that the presence of Cl- ions in the anodising bath inhibits the oxidation process and the degree of inhibition is dependent on

G. S. Nadkarni; S. Radhakrishnan; S. V. Maduskar

1984-01-01

185

Crystal Structure of beta-Aluminium-Magnesium Alloy  

Microsoft Academic Search

A PIECE of beta-aluminium-magnesium alloy of irregular shape, when examined by the Laue method, showed all the characteristics of the Laue symmetry m3m = 0h, which proves conclusively that beta Al-Mg is cubic and not hexagonal as assumed by K. Riederer1. By means of rotation photograms the length of the edge of the unit cube was determined to be a

Harald Perlitz

1944-01-01

186

Surface Analysis and Bonding of Aluminium-Magnesium Alloys  

Microsoft Academic Search

Previous work has used X-ray photoelectron spectroscopy to examine the surface compositions of aluminium-alloy substrates subjected to various surface pretreatments prior to bonding. It was proposed that the presence of magnesium in the oxide structure adversely affected the service-life of adhesive joints when they were exposed to aqueous environments. The present work further explores this correlation by examining a range

A. J. Kinloch; H. E. Bishop; N. R. Smart

1982-01-01

187

Creep of aluminium–magnesium open cell foam  

Microsoft Academic Search

Aluminium–5wt.% magnesium open cell foam produced by replication and tested in tension at 300, 350 or 450°C creeps at rates between 10?3 and 10?8s?1. The behaviour of the foam matches that of the alloy from which it is made: three-power law creep with the same activation energy as for Al–Mg alloy creeping by viscous dislocation glide in the high stress

Frédéric Diologent; Russell Goodall; Andreas Mortensen

2009-01-01

188

Mechanism of high strain rate superplasticity in aluminium alloy composites  

Microsoft Academic Search

A constitutive equation has been obtained through an analysis of high strain rate superplasticity (HSRS) data on a 2124 Al?Si?3N4 composite. The parametric dependencies of HSRS in composites are different from those observed in conventional aluminium alloys and mechanically alloyed alloys. The HSRS in composites exhibits high activation energy values of 293–338 kJ mol?1 and an inverse grain size and

R. S. Mishra; T. R. Bieler; A. K. Mukherjee

1997-01-01

189

Manufacturing low density boards from waste cardboards containing aluminium  

Microsoft Academic Search

We tried to recycle waste Tetra Pak cardboards, which contain aluminium as a step in the prevention of the environmental pollution caused by municipal solid wastes and as methods of achieving economical worth from these. The composite prepared with urea–formaldehyde resin was harder relative to that prepared with polyvinyl acetate based glue. The target cardboard density and thickness were 0.5g\\/cm3

Atilla Murathan; Ay?e Selek Murathan; Metin Gürü; Muzaffer Balba??

2007-01-01

190

PROPRITS MAGNTIQUES DU GRENAT D'ALUMINIUM ET DE DYSPROSIUM I. THORIE A 0 K  

E-print Network

57. PROPRI�T�S MAGN�TIQUES DU GRENAT D'ALUMINIUM ET DE DYSPROSIUM I. TH�ORIE A 0 °K Par R. BIDAUX'aluminium et de dysprosium l'application d'un champ magnétique assez intense est susceptible de découpler les'aluminium et de dysprosium (DAG) d'un champ magnétique appliqué parallèlement à un axe ternaire ou quaternaire

Paris-Sud XI, Université de

191

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. PMID:21976787

Bachmaier, Andrea; Pippan, Reinhard

2011-01-01

192

Study on fisetin–aluminium(III) interaction in aqueous buffered solutions by spectroscopy and molecular modeling  

Microsoft Academic Search

Spectroscopic (UV\\/visible and IR) and theoretical studies were used to assess relevant interaction of fisetin, a tetrahydroxylated flavone molecule, and trivalent aluminium in a wide range of buffered aqueous solutions. The chelation sites, stoichiometry, stability and the dependence of the complexes structures on pH and aluminium\\/fisetin mole ratios were defined. Obtained results implicated successive formation of two complexes with aluminium(III)–fisetin

Jasmina M. Dimitri? Markovi?; Zoran S. Markovi?; Dragan S. Veselinovi?; Jugoslav B. Krsti?; Jasmina D. Predojevi? Simovi?

2009-01-01

193

Laser synthesis of aluminium nanoparticles in biocompatible polymer solutions  

NASA Astrophysics Data System (ADS)

Pulsed laser ablation of Aluminium (Al) in pure water rapidly forms a thin alumina (Al2O3) layer which drastically modifies surface plasmon resonance (SPR) absorption characteristics in deep-UV region. Initially, pure aluminium nanoparticles (NPs) are generated in water without any stabilizers or surfactants at low laser fluence which gradually transform to stable Al-Al2O3 core-shell nanostructure with increasing either residency time or fluence. The role of laser wavelength and fluence on the SPR properties and oxidation characteristics of Al NPs has been investigated in detail. We also present a one-step in situ synthesis of oxide-free stable Al NPs in biocompatible polymer solutions using laser ablation in liquid method. We have used nonionic polymers (PVP, PVA and PEG) and anionic surfactant (SDS) stabilizer to suppress the Al2O3 formation and studied the effect of polymer functional group, polymeric chain length, polymer concentration and anionic surfactant on the incipient embryonic aluminium particles and their sizes. The different functional groups of polymers resulted in different oxidation states of Al. PVP and PVA polymers resulted in pure Al NPs; however, PEG and SDS resulted in alumina-modified Al NPs. The Al nanoparticles capped with PVP, PVA, and PEG show a good correlation between nanoparticle stability and monomeric length of the polymer chain.

Singh, Rina; Soni, R. K.

2014-08-01

194

High rate constitutive modeling of aluminium alloy tube  

NASA Astrophysics Data System (ADS)

As the need for fuel efficient automobiles increases, car designers are investigating light-weight materials for automotive bodies that will reduce the overall automobile weight. Aluminium alloy tube is a desirable material to use in automotive bodies due to its light weight. However, aluminium suffers from lower formability than steel and its energy absorption ability in a crash event after a forming operation is largely unknown. As part of a larger study on the relationship between crashworthiness and forming processes, constitutive models for 3mm AA5754 aluminium tube were developed. A nominal strain rate of 100/s is often used to characterize overall automobile crash events, whereas strain rates on the order of 1000/s can occur locally. Therefore, tests were performed at quasi-static rates using an Instron test fixture and at strain rates of 500/s to 1500/s using a tensile split Hopkinson bar. High rate testing was then conducted at rates of 500/s, 1000/s and 1500/s at 21circC, 150circC and 300circC. The generated data was then used to determine the constitutive parameters for the Johnson-Cook and Zerilli-Armstrong material models.

Salisbury, C. P.; Worswick, M. J.; Mayer, R.

2006-08-01

195

X-ray micro-analysis of aluminium in pumpkinseed gills.  

PubMed

Energy dispersive X-ray micro-analysis was applied to study the (sub-) cellular distribution of aluminium at the gill level of "acid-resistant pumpkinseeds (Lepomis gibbosus) exposed to acidified water (pH = 4.2) and an elevated level of aluminium (1.4 mg Al/l, exposure period = 21 days). Electron dense deposits, located in invaginations as well as inside the gill tissue, were shown to contain elevated levels of aluminium and phosphorus. The micro-analytical findings suggest that the pumpkinseed possesses a defence mechanism, in which the intracellular accumulation of aluminium is limited to restricted sites and to storage in macrophages. PMID:8398556

Eeckhaoudt, S; Jacob, W; Witters, H; Van Grieken, R

1993-01-01

196

Galvanic interactions of aluminium 3004 and ? brass in tropical marine atmosphere  

NASA Astrophysics Data System (ADS)

The galvanic corrosion behaviour of aluminium 3004 - ? brass with different area ratios was studied in the tropical marine atmosphere at Tuticorin harbour over a period of 426 days. The area ratios, viz. A Aluminium: A ? brass, studied were 0.125, 0.25, 0.5, 1, 2, 4 and 8. The galvanic corrosion behaviour of the metals was studied in terms of the relative increase in the corrosion rate of aluminium due to galvanic coupling with ? brass, the relative decrease in the corrosion rate of ? brass due to galvanic coupling with aluminium, and the susceptibility of aluminium to pitting owing to galvanic coupling with ? brass. The galvanic potential and galvanic current of the system were monitored. Pits of different dimensions ranging from mild etchings to perforations were experienced on the borders and the surfaces of the interface of aluminium in contact with ? brass. The corrosion products resulting from galvanic corrosion were analysed using XRD and the pitting on aluminium as a result of galvanic corrosion was highlighted in terms of pit depth, size and density of pit, using a high resolution microscope. The most favourable area ratio of aluminium — ? brass in marine atmosphere in terms of gravimetric corrosion rate is 8:1 and the most unfavourable area ratio of aluminium — ? brass is 1:4.

Palraj, S.; Subramanian, G.; Palanichamy, S.

2014-12-01

197

Dietary Exposure to Aluminium and Health Risk Assessment in the Residents of Shenzhen, China  

PubMed Central

Although there are great changes of dietary in the past few decades in China, few are known about the aluminium exposure in Chinese diet. The aim of this study is to systematically evaluate the dietary aluminium intake level in residents of Shenzhen, China. A total of 853 persons from 244 household were investigated their diet by three days food records. Finally, 149 kinds of foods in 17 food groups were selected to be the most consumed foods. From them, 1399 food samples were collected from market to test aluminium concentration. High aluminium levels were found in jellyfish (median, 527.5 mg/kg), fried twisted cruller (median, 466.0 mg/kg), shell (median, 107.1 mg/kg). The Shenzhen residents' average dietary aluminium exposure was estimated at 1.263 mg/kg bw/week which is lower than the PTWI (provisional tolerable weekly intake). But 0–2 and 3–13 age groups have the highest aluminium intake exceeding the PTWI (3.356 mg/kg bw/week and 3.248 mg/kg bw/week) than other age groups. And the main dietary aluminium exposure sources are fried twisted cruller, leaf vegetables and bean products. Our study suggested that even three decades rapid economy development, children in Shenzhen still have high dietary aluminium exposure risk. How to control high dietary aluminium exposure still is a great public health challenge in Shenzhen, China. PMID:24594670

Yang, Mei; Jiang, Lixin; Huang, Huiping; Zeng, Shengbo; Qiu, Fen; Yu, Miao; Li, Xiaorong; Wei, Sheng

2014-01-01

198

The response of macroinvertebrates to experimental episodes of low pH with different forms of aluminium, during a natural spate  

Microsoft Academic Search

24 h experimental episodes were created in a soft-water stream in upland Wales, by the simultaneous addition at separate points\\u000a of sulphuric acid, aluminium sulphate and citric acid. In an upstream reference zone (A) the pH remained above 7, while in\\u000a the treatment zones, B, C and D successively downstream, it was reduced to c. pH 4.9. Concentrations of filterable

N. S. Weatherley; S. J. Ormerod; S. P. Thomas; R. W. Edwards

1988-01-01

199

Study of twin-roll cast Aluminium alloys subjected to severe plastic deformation by equal channel angular pressing  

NASA Astrophysics Data System (ADS)

Aluminium alloys prepared by twin-roll casting method become widely used in industry applications. Their high solid solution supersaturation and finer grains ensure better mechanical properties when compared with the direct-chill cast ones. One of the possibilities how to enhance their thermal stability is the addition of zirconium. After heat treatment Al3Zr precipitates form and these pin moving grain boundaries when the material is exposed to higher temperatures. In the present work twin-roll cast aluminium alloys based on AA3003 with and without Zr addition were annealed for 8 hours at 450 °C to enable precipitation of Al3Zr phase. Afterwards they were subjected to severe plastic deformation by equal channel angular pressing, which led to the reduction of average grain size under 1 ?m. During subsequent isochronal annealing recovery and recrystallization took place. These processes were monitored by microhardness measurements, light optical microscopy and in-situ transmission electron microscopy. The addition of Zr stabilizes the grain size and increases the recrystallization temperature by 100 °C.

Poková, M.; Cieslar, M.

2014-08-01

200

The Tungsten Inert GAS (TIG) Process of Welding Aluminium in Microgravity: Technical and Economic Considerations  

NASA Astrophysics Data System (ADS)

The UNIBO team composed of students and professors of the University of Bologna along with technicians and engineers from Alenia Space Division and Siad Italargon Division, took part in the 3rd Student Parabolic Flight Campaign of the European Space Agency in 2000. It won the student competition and went on to take part in the Professional Parabolic Flight Campaign of May 2001. The experiment focused on "dendritic growth in aluminium alloy weldings", and investigated topics related to the welding process of aluminium in microgravity. The purpose of the research is to optimise the process and to define the areas of interest that could be improved by new conceptual designs. The team performed accurate tests in microgravity to determine which phenomena have the greatest impact on the quality of the weldings with respect to penetration, surface roughness and the microstructures that are formed during the solidification. Various parameters were considered in the economic-technical optimisation, such as the type of electrode and its tip angle. Ground and space tests have determined the optimum chemical composition of the electrodes to offer longest life while maintaining the shape of the point. Additionally, the power consumption has been optimised; this offers opportunities for promoting the product to the customer as well as being environmentally friendly. Tests performed on the Al-Li alloys showed a significant influence of some physical phenomena such as the Marangoni effect and thermal diffusion; predictions have been made on the basis of observations of the thermal flux seen in the stereophotos. Space transportation today is a key element in the construction of space stations and future planetary bases, because the volumes available for launch to space are directly related to the payload capacity of rockets or the Space Shuttle. The research performed gives engineers the opportunity to consider completely new concepts for designing structures for space applications. In fact, once the optimised parameters are defined for welding in space, it could be possible to weld different parts directly in orbit to obtain much larger sizes and volumes, for example for space tourism habitation modules. The second relevant aspect is technology transfer obtained by the optimisation of the TIG process on aluminium which is often used in the automotive industry as well as in mass production markets.

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

2002-01-01

201

Modelling the environmental degradation of adhesively bonded aluminium and composite joints using a CZM approach  

Microsoft Academic Search

The long-term durability of adhesively bonded aluminium, composite and dissimilar substrate joints exposed to humid environments has been investigated. Failure of the joints was modelled with a cohesive zone model (CZM) approach where the governing parameters were determined from fracture mechanics test specimens saturated in a range of humid environments. The reduction in residual strength of an aluminium single lap

C. D. M. Liljedahl; A. D. Crocombe; M. A. Wahab; I. A. Ashcroft

2007-01-01

202

Spot diagnosis of aluminium phosphide ingestion: an application of a simple test.  

PubMed

Silver nitrate impregnated paper test was performed with the gastric fluid and in breath in 50 patients of aluminium phosphide poisoning. The test was 100% positive with gastric fluid but was positive in 50% patients in breath. The test is simple, reliable and sensitive method to detect phosphine (PH3) for bed side diagnosis of aluminium phosphide (AIP) ingestion. PMID:2768165

Chugh, S N; Ram, S; Chugh, K; Malhotra, K C

1989-03-01

203

EVALUATION OF Staphylococcus aureus AND Streptococcus agalactiae ALUMINIUM HYDROXIDE ADJUVANTED MASTITIS VACCINE IN RABBITS  

Microsoft Academic Search

The aim of present study was to prepare and evaluate Staphylococcus aureus and Streptococcus agalactiae aluminium hydroxide adjuvanted mastitis vaccine in rabbits. For this purpose, isolates of these two bacterial species were recovered from aseptically collected milk samples (n=95) of mastitic buffaloes, identified and bio- characterized. Pathogenicity, immunogenicity, and antibiotics sensitivity testing of vaccinal organisms was performed. A bivalent aluminium

Tanveer Ahmadand GhulamMuhammad

2008-01-01

204

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

205

Assessment of the cytotoxicity of aluminium oxide nanoparticles on selected mammalian cells  

Microsoft Academic Search

The rapid development of nanotechnology raises both enthusiasm and anxiety among researchers, which is related to the safety use of the manufactured materials. Thus, the aim of this study was to investigate the effect of aluminium oxide nanoparticles on the viability of selected mammalian cells in vitro. The aluminium oxide nanoparticles were characterised using SEM and BET analyses. Based on

E. Radziun; J. Dudkiewicz Wilczy?ska; I. Ksi??ek; K. Nowak; E. L. Anuszewska; A. Kunicki; A. Olszyna; T. Z?bkowski

206

The mechanical behaviour of aluminium foam structures in different loading conditions  

Microsoft Academic Search

The use of foam has the potential for energy absorption enhancement. Many types of materials can be produced in the form of foams, including metals and polymers. Of the metallic based foams, aluminium based are among the most advanced. Aluminium foams couple good specific mechanical properties with high thermal stability. Among the various aspects still to be investigated regarding their

Lorenzo Peroni; Massimiliano Avalle; Marco Peroni

2008-01-01

207

A kinetic and electrochemical study of the zincate immersion process for aluminium  

Microsoft Academic Search

To plate aluminium, its surface is often first coated with a thin layer of zinc which is formed by immersion in an alkaline zincate solution. This paper describes a kinetic and electrochemical study of the zincate immersion reaction. Using an aluminium sample in the form of a rotating disc, the effects of varying the zinc concentration (0.01–0.5 m), disc rotation

S. G. Robertson; I. M. Ritchie; D. M. Druskovich

1995-01-01

208

Experimental Model of the Interfacial Instability in Aluminium Reduction Cells A.Pedchenko,  

E-print Network

done before PACS numbers: Overcoming magnetohydrodynamic (MHD) instabili- ties in aluminium reduction billion annually [2]. Thus the efficiency of the process of aluminium smelting has considerable economic to MHD waves if parame- ters of the process rise above or fall below certain thresh- olds. The key

Lukyanov, Alex

209

The effect of atmospheric corona treatment on AA1050 aluminium M. Jariyaboon a,1  

E-print Network

The effect of atmospheric corona treatment on AA1050 aluminium M. Jariyaboon a,1 , P. Møller a , R t The effect of atmospheric corona discharge on AA1050 aluminium surface was investigated using electro, 5, and 15 min) in atmospheric air. A 200 nm oxide layer was generated on AA1050 after the 15 min air

Dunin-Borkowski, Rafal E.

210

Interaction of aluminium ions with some amino acids present in human blood  

Microsoft Academic Search

Summary. The interaction of aluminium with some amino acids present in human blood was studied combining ion-chromatography (IC), atomic absorption spectrometry (AAS) and ultrafiltration (UF) techniques. An IC system for simultaneous determination of ornithine, lysine, glutamic acid, aspartic acid and tyrosine was developed. By adding aluminium to standard solutions of the amino acids and keeping the pH at 6 and

D. Bohrer; P. C. do Nascimento; J. K. A. Mendonça; V. G. Polli; L. M. de Carvalho

2004-01-01

211

The role of magnesium in the electrochemical behaviour of 5XXX aluminium-magnesium alloys  

Microsoft Academic Search

An investigation concerning the effects of magnesium on the intergranular corrosion susceptibility of AA5XXX aluminium alloys was carried out. In the present work, magnesium is found to be highly mobile in the bulk metal as well as in the aluminium oxide. This mobility is also found to be dependent on the temperature and bulk magnesium concentration. Interestingly, the corrosion susceptibility

J. R. Flores Ramirez

2006-01-01

212

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. PMID:9166127

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

1997-01-01

213

Effect of the aluminium concentration on the resonant tunnelling time and the laser wavelength of random trimer barrier AlxGa1-xAs superlattices  

NASA Astrophysics Data System (ADS)

In this study, we investigated numerically the effect of aluminium concentration on the resonant tunnelling time (RTT) and the laser wavelength of random trimer barrier AlxGa1-xAs superlattices (RTBSL). Such systems consist of two different structures randomly distributed along the growth direction, with the additional constraint that the barriers of one kind appear in triply. An explicit formula is given for evaluating the transmission coefficient of superlattices (SL's) with intentional correlated disorder. The method is based on Airy function formalism and the transfer-matrix technique. We discuss the impact of the aluminium concentration associated to the structural profile of the SL's on the RTT and the laser wavelengths.

Bendahma, F.; Bentata, S.; Djelti, R.; Aziz, Z.

2014-09-01

214

The fracture of boron fibre-reinforced 6061 aluminium alloy  

NASA Technical Reports Server (NTRS)

The fracture of 6061 aluminium alloy reinforced with unidirectional and cross-plied 0/90 deg, 0/90/+ or - 45 deg boron fibres has been investigated. The results have been described in terms of a critical stress intensity, K(Q). Critical stress intensity factors were obtained by substituting the failure stress and the initial crack length into the appropriate expression for K(Q). Values were obtained that depended on the dimensions of the specimens. It was therefore concluded that, for the size of specimen tested, the values of K(Q) did not reflect any basic materials property.

Wright, M. A.; Welch, D.; Jollay, J.

1979-01-01

215

Deviatoric Response of AN Armour-Grade Aluminium Alloy  

NASA Astrophysics Data System (ADS)

Aluminium alloys such as 5083 H32 are established light-weight armour materials. As such, the shock response of these materials is of great importance. The shear strength of a material under shock loading provides an insight into its ballistic performance. In this investigation embedded manganin stress gauges have been employed to measure both the longitudinal and lateral components of stress during plate-impact experiments over a range of impact stresses. In turn, these results were used to determine the shear strength and to investigate the time dependence of lateral stress behind the shock front to give an indication of material response.

Appleby-Thomas, G. J.; Hazell, P. J.; Millett, J.; Bourne, N. K.

2009-12-01

216

Release Behaviour of Shock Loaded LY12 Aluminium Alloy  

NASA Astrophysics Data System (ADS)

By making use of a light gas gun, a specially designed target is impacted by the LY12 flyer, and the pressure is taken in the range of 0.6-3 GPa. Based on the stress profiles measured in the buffer materials by manganese gauges, the Hugoniot curve and release curves of LY12 aluminium alloy are obtained. Meanwhile, the release curves from different initial shocked states are described in both the pressure-particle velocity plane and the pressure-specific volume plane.

Yan, Min; Dai, Lan-Hong; Shen, Le-Tian

2005-11-01

217

Controlling interferometric properties of nanoporous anodic aluminium oxide  

NASA Astrophysics Data System (ADS)

A study of reflective interference spectroscopy [RIfS] properties of nanoporous anodic aluminium oxide [AAO] with the aim to develop a reliable substrate for label-free optical biosensing is presented. The influence of structural parameters of AAO including pore diameters, inter-pore distance, pore length, and surface modification by deposition of Au, Ag, Cr, Pt, Ni, and TiO2 on the RIfS signal (Fabry-Perot fringe) was explored. AAO with controlled pore dimensions was prepared by electrochemical anodization of aluminium using 0.3 M oxalic acid at different voltages (30 to 70 V) and anodization times (10 to 60 min). Results show the strong influence of pore structures and surface modifications on the interference signal and indicate the importance of optimisation of AAO pore structures for RIfS sensing. The pore length/pore diameter aspect ratio of AAO was identified as a suitable parameter to tune interferometric properties of AAO. Finally, the application of AAO with optimised pore structures for sensing of a surface binding reaction of alkanethiols (mercaptoundecanoic acid) on gold surface is demonstrated.

Kumeria, Tushar; Losic, Dusan

2012-01-01

218

Experimental study of aluminium honeycomb behaviour under dynamic multiaxial loading  

NASA Astrophysics Data System (ADS)

Split Hopkinson Pressure Bar system (SHPB) with large-diameter and Nylon bars introducing a shear-compression loading device is used in order to investigate the dynamic behaviour of aluminium honeycomb under multiaxial loadings conditions. All shear-compression configurations including the loading angle variation from 0? to 60? are performed with an impact velocity of about 15m/s. The adapted SHPB system with the device are validated numerically and a phenomenon of separation between the input bar and the input beveled bar is observed. Numerical results suggest that this phenomenon provides a cutting of the reflected wave. An electro optical extensometer is employed in experiments. A good agreement between the numerical elastic waves and the experimental ones is obtained. Experimental results show a significant effect of the loading angle on the apparent stress-strain curves. The initial peak value and the plateau stress decrease with the increase of the loading angle. The combined shear-compression device with an enhancement at the alignment set-up provides efficient results for samples dynamically loaded. This device will be used to investigate the influence of the in-plane orientation angle on the deformation mechanisms and multiaxial behaviour of aluminium honeycomb under dynamic and quasi-static loading conditions.

Tounsi, R.; Zouari, B.; Chaari, F.; Haugou, G.; Markiewicz, E.; Dammak, F.

2012-08-01

219

Aluminium adjuvants and adverse events in sub-cutaneous allergy immunotherapy.  

PubMed

Sub-cutaneous immunotherapy is an effective treatment for allergy. It works by helping to modify or re-balance an individual's immune response to allergens and its efficacy is greatly improved by the use of adjuvants, most commonly, aluminium hydroxide. Aluminium salts have been used in allergy therapy for many decades and are assumed to be safe with few established side-effects. This assumption belies their potency as adjuvants and their potential for biological reactivity both at injection sites and elsewhere in the body. There are very few data purporting to the safety of aluminium adjuvants in allergy immunotherapy and particularly so in relation to longer term health effects. There are, if only few, published reports of adverse events following allergy immunotherapy and aluminium adjuvants are the prime suspects in the majority of such incidents. Aluminium adjuvants are clearly capable of initiating unwanted side effects in recipients of immunotherapy and while there is as yet no evidence that such are commonplace it is complacent to consider aluminium salts as harmless constituents of allergy therapies. Future research should establish the safety of the use of aluminium adjuvants in sub-cutaneous allergy immunotherapy. PMID:24444186

Exley, Christopher

2014-01-01

220

Aluminium adjuvants and adverse events in sub-cutaneous allergy immunotherapy  

PubMed Central

Sub-cutaneous immunotherapy is an effective treatment for allergy. It works by helping to modify or re-balance an individual’s immune response to allergens and its efficacy is greatly improved by the use of adjuvants, most commonly, aluminium hydroxide. Aluminium salts have been used in allergy therapy for many decades and are assumed to be safe with few established side-effects. This assumption belies their potency as adjuvants and their potential for biological reactivity both at injection sites and elsewhere in the body. There are very few data purporting to the safety of aluminium adjuvants in allergy immunotherapy and particularly so in relation to longer term health effects. There are, if only few, published reports of adverse events following allergy immunotherapy and aluminium adjuvants are the prime suspects in the majority of such incidents. Aluminium adjuvants are clearly capable of initiating unwanted side effects in recipients of immunotherapy and while there is as yet no evidence that such are commonplace it is complacent to consider aluminium salts as harmless constituents of allergy therapies. Future research should establish the safety of the use of aluminium adjuvants in sub-cutaneous allergy immunotherapy. PMID:24444186

2014-01-01

221

Laser welding of aluminium alloys 5083 and 6082 under conduction regime  

NASA Astrophysics Data System (ADS)

In this work, samples of aluminium alloys 5083-T0 and 6082-T6 have been welded under conduction regime, using a high power diode laser. The influence of experimental variables, as the laser power and the linear welding rate, on the sizes and properties of the butt weld beads has been studied. In addition to measure the depths and widths of the weld beads, their microstructure, microhardness profile and corrosion resistance have been analysed. The results obtained allow one to define the experimental conditions leading to good quality butt welds with higher penetration than those published in the recent literature under conduction regime. Maximum penetration values of 3 and 2.3 mm were obtained for 5083 and 6082, respectively. Additionally, a simple mathematical expression relating the weld depth ( d) with the laser power ( P) and the processing rate ( v) has been proposed: d=(P-bb)/(av)-(ba)/a, being a, a', b and b' constant values for each alloy and under the employed experimental conditions. The values of these coefficients have been estimated from the fitting to the experimental depth values of 5083 and 6082 butt welds generated under conduction regime.

Sánchez-Amaya, J. M.; Delgado, T.; González-Rovira, L.; Botana, F. J.

2009-09-01

222

Cobalt and Nickel Nanopillars on Aluminium Substrates by Direct Current Electrodeposition Process  

PubMed Central

A fast and cost-effective technique is applied for fabricating cobalt and nickel nanopillars on aluminium substrates. By applying an electrochemical process, the aluminium oxide barrier layer is removed from the pore bottom tips of nanoporous anodic alumina templates. So, cobalt and nickel nanopillars are fabricated into these templates by DC electrodeposition. The resulting nanostructure remains on the aluminium substrate. In this way, this method could be used to fabricate a wide range of nanostructures which could be integrated in new nanodevices. PMID:20596338

2009-01-01

223

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

2013-10-01

224

Shape-diversified silver nanostructures uniformly covered on aluminium micro-powders as effective SERS substrates  

NASA Astrophysics Data System (ADS)

Highly-sensitive, reliable and reproducible Raman-active substrates via a facile and organic-free method are reported. These intriguing hierarchical structures are formed through the uniform incorporation of silver (Ag) nanoflowers with aluminium (Al) micro-supporters. The underlying mechanism is systematically investigated, visualizing that the solvents used in galvanic displacement have a major effect on diversifying the reaction kinetics of Ag deposition. Moreover, the exploration of AgNO3 concentrations reveals a drastic transition of Ag morphologies, driven by the elimination of high-energy surfaces of Ag. In addition, the surface-modified Al@Ag structures with octadecyltrichlorosilane demonstrate both the non-wetting (contact angle = 157.2°), as well as easy droplet roll-off (contact angle hysteresis = 5.4°) characteristics, which further enables the tested targets to avoid being pinned at a static position upon detection. Finally, we find that the Ag nanoflower surfaces are corrugated with numerous nanogaps at interparticle sites, in such a way that allows the abundant active sites (referred to as ``hot spots'') to amplify the Raman signal, and simultaneously maintain the sound reliability and reproducibility of Raman detection. These designs along with the fabrication strategy are anticipated to benefit versatile optical, optoelectronic and energy devices.Highly-sensitive, reliable and reproducible Raman-active substrates via a facile and organic-free method are reported. These intriguing hierarchical structures are formed through the uniform incorporation of silver (Ag) nanoflowers with aluminium (Al) micro-supporters. The underlying mechanism is systematically investigated, visualizing that the solvents used in galvanic displacement have a major effect on diversifying the reaction kinetics of Ag deposition. Moreover, the exploration of AgNO3 concentrations reveals a drastic transition of Ag morphologies, driven by the elimination of high-energy surfaces of Ag. In addition, the surface-modified Al@Ag structures with octadecyltrichlorosilane demonstrate both the non-wetting (contact angle = 157.2°), as well as easy droplet roll-off (contact angle hysteresis = 5.4°) characteristics, which further enables the tested targets to avoid being pinned at a static position upon detection. Finally, we find that the Ag nanoflower surfaces are corrugated with numerous nanogaps at interparticle sites, in such a way that allows the abundant active sites (referred to as ``hot spots'') to amplify the Raman signal, and simultaneously maintain the sound reliability and reproducibility of Raman detection. These designs along with the fabrication strategy are anticipated to benefit versatile optical, optoelectronic and energy devices. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr04956f

Chen, Chia-Yun; Wong, Ching-Ping

2013-12-01

225

Nanostructural hierarchy increases the strength of aluminium alloys.  

PubMed

Increasing the strength of metallic alloys while maintaining formability is an interesting challenge for enabling new generations of lightweight structures and technologies. In this paper, we engineer aluminium alloys to contain a hierarchy of nanostructures and possess mechanical properties that expand known performance boundaries-an aerospace-grade 7075 alloy exhibits a yield strength and uniform elongation approaching 1 GPa and 5%, respectively. The nanostructural architecture was observed using novel high-resolution microscopy techniques and comprises a solid solution, free of precipitation, featuring (i) a high density of dislocations, (ii) subnanometre intragranular solute clusters, (iii) two geometries of nanometre-scale intergranular solute structures and (iv) grain sizes tens of nanometres in diameter. Our results demonstrate that this novel architecture offers a design pathway towards a new generation of super-strong materials with new regimes of property-performance space. PMID:20842199

Liddicoat, Peter V; Liao, Xiao-Zhou; Zhao, Yonghao; Zhu, Yuntian; Murashkin, Maxim Y; Lavernia, Enrique J; Valiev, Ruslan Z; Ringer, Simon P

2010-01-01

226

Serial blood phosphine levels in acute aluminium phosphide poisoning.  

PubMed

Serial blood phosphine (PH3) levels were done in patients with severe (Group I, n = 30), mild (Group 2, n = 10) and minimal or nil toxicity due to aluminium phosphide compound. Blood phosphine levels were significantly higher (p < 0.001) in patients of Group I than other two groups. Phosphine was not detectable in Group 3 patients. Therefore, blood phosphine levels were positively correlated to clinical grades of toxicity and to dose of active pesticide consumed. Higher the blood phosphine, higher was the mortality. Patients having blood phosphine levels equal to or less than 1.067 +/- 0.16 mg% survived, hence, it appeared to be limit of phosphine toxicity. PMID:9251315

Chugh, S N; Pal, R; Singh, V; Seth, S

1996-03-01

227

Acute phosphine poisoning following ingestion of aluminium phosphide.  

PubMed

1. Eight cases of phosphine poisoning following ingestion of aluminium phosphide tablets for suicidal attempt are described. The mean age of the patients was 23 years (range 14-25). 2. The clinical picture consisted of gastritis, altered sensorium and peripheral vascular failure in all cases, cardiac arrhythmia (3), jaundice and renal failure (1 each). Six patients died, the mean hospital stay was 19 h (range 4-72). 3. Post-mortem examination was performed in two patients, revealing pulmonary oedema, gastrointestinal mucosal congestion, petechial haemorrhages on the surface of liver and brain. Histopathological changes included pulmonary oedema, desquamation of the lining epithelium of the bronchioles; vacuolar degeneration of hepatocytes, dilatation and engorgement of hepatic central veins, sinusoids and areas showing nuclear fragmentation. 4. The clinical picture of aluminum phosphide poisoning is described and precaution in the distribution and use of this pesticide recommended. PMID:3410483

Misra, U K; Tripathi, A K; Pandey, R; Bhargwa, B

1988-07-01

228

Pulmonary Fibrosis in Workers Exposed to Finely Powdered Aluminium  

PubMed Central

Of 30 workmen at risk 27 were examined and six found to have evidence of pulmonary fibrosis. In the two fatal cases the evidence for pulmonary fibrosis was conclusive and in three other cases it was sufficient; in one case it was suggestive. The clinical, radiological, and pathological features of these six cases are recorded. Results of respiratory function tests on the four non-fatal cases are given. The manufacturing process is described. An analysis of the powder is given, also the results of dust measurement in the contaminated atmosphere. The literature is reviewed and our own experience compared with reports from Germany and Canada. We concluded that the pulmonary fibrosis was caused by the dust inhaled at work and that the component responsible was finely divided aluminium. Images PMID:13771334

Mitchell, John; Manning, G. B.; Molyneux, M.; Lane, Ronald E.

1961-01-01

229

Excimer laser induced surface nitriding of aluminium alloy  

NASA Astrophysics Data System (ADS)

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 atom diffusion and reaction into the depth of the sample. Plasma spots were overlapped by two dimensional laser beam displacement to ensure the complete coating of the surface with a specified laser fluence (1.6 J/cm 2) and number of pulses (500), while not removing of the nitride layer already synthesised. Under these conditions, the diffusion layer penetrates a few ?m deep, but its crystalline quality is preserved. Interesting information on the layer formation and composition are drawn from nuclear analysis (RBS and NRA) to determine the nitrogen and oxygen (contaminant) concentration profiles.

Sicard, E.; Boulmer-Leborgne, C.; Sauvage, T.

1998-05-01

230

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

231

Multicomponental fluorimetric determination of aluminium, gallium and indium.  

PubMed

For the fast characteristics of mixtures of Aluminium, Gallium and Indium the fluorimetric evaluation in the form of complexes with 8-Hydroxyquinoline-5-sulphonic acid is described at selected pH. The highly collinear correlated fluorescent spectra and their first derivation were evaluated under various experimental conditions with the Multiple Linear Regression (MLR), Partial Least Squares (PLS) methods and Kalman filtering. When comparing the results, the PLS gives the least relative prediction errors under optimal conditions, 5.6-15.9% for the concentration range of Al 0.025-0.2 microg cm(-3), Ga 0.1-0.8 microgcm(-3) and In 0.1-0.8 microg cm(-3) in the mixture. PMID:18080828

Vojta, Simon; Jancár, Ludek; Sommer, Lumír

2008-03-01

232

addition and subtraction  

NSDL National Science Digital Library

How are addition and subtraction problems related? Recording chart Graphic Organizer Use this link to work on addition with pictures. addition with pictures Go here to work on addition with sentences. addition with sentences Now, go here to work on subtraction sentences. Subtraction sentences Use this link to practice subtraction with pictures. Subtraction with pictures Now let's review! Click here. Fact Family Practice ...

Ms. Hayes

2011-04-07

233

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

PubMed

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 (TiCl(4), BiCl(3), InCl(3) or PbCl(2)) 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. PMID:21124514

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

2010-04-01

234

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

235

Mid-Infrared Spectroscopy of Calcium-Aluminium-Rich Inclusions: A Tool to Detect Primitive Asteroids?  

NASA Astrophysics Data System (ADS)

Calcium-aluminium-rich inclusions in Vigarano, Ornans and Allende have characteristic refractory components that may help us identify primitive near-Earth asteroids through mid-IR space telescope spectrometers. We have identified some features.

Melwani Daswani, M.; Morlok, A.; Wolters, S. D.; Grady, M. M.

2014-09-01

236

Alternative Addition Strategies  

NSDL National Science Digital Library

This lesson explores recall of multiple alternative addition strategies of two-digit numbers. The lesson focus is to encourage students to use more than one strategy to solve addition problems. By reinforcing the multiple alternative addition strategies students will develop a strong understanding of addition structures and mechanics before moving on to three-digit addition. The lesson includes making an Addition Strategies Mini Booklet, which students can keep and use as a reference tool.

Judith Scapecchi

2012-07-31

237

Boiling water and silane pre-treatment of aluminium alloys for durable adhesive bonding  

Microsoft Academic Search

Three series of aluminium alloys received a surface pre-treatment including immersion in boiling water followed by soaking in a 1% aqueous solution of 3-glycidoxytrimethoxysilane. When aluminium was pre-treated in this manner, adhesive joints formed with a range of epoxy resins produced notable improvements in bond durability in comparison with simple abrasion pre-treatments. In some cases, the pre-treatment improved joint durability

A. N Rider; D. R Arnott

2000-01-01

238

A numerical model for bird strike of aluminium foam-based sandwich panels  

Microsoft Academic Search

Experimental bird-strike tests have been carried out on double sandwich panels made from AlSi7Mg0.5 aluminium foam core and aluminium AA2024 T3 cover plates. The bird-strike velocity varied from 140 to 190m\\/s. The test specimens were instrumented with strain gauges in the impacted area to measure the local strains of the rear sandwich plate. A numerical model of this problem has

A. G. Hanssen; Y. Girard; L. Olovsson; T. Berstad; M. Langseth

2006-01-01

239

TUDE D'UNE CONTAMINATION VENTUELLE PAR L'ALUMINIUM DANS LES SOURCES DE POLONIUM,  

E-print Network

�TUDE D'UNE CONTAMINATION �VENTUELLE PAR L'ALUMINIUM DANS LES SOURCES DE POLONIUM, LES SUPPORTS DE oc du polonium d'énergie 5,29 MeV peuvent donner des protons de transmutation avec l'aluminium d émissions de sources de radioéléments naturels et notamment dans le rayonnement des sources de polonium (1

Paris-Sud XI, Université de

240

Aluminium induced oxidative stress and DNA damage in root cells of Allium cepa L  

Microsoft Academic Search

Aluminium (Al) was evaluated for induction of oxidative stress and DNA damage employing the growing roots of Allium cepa L. as the assay system. Intact roots of A. cepa were treated with different concentrations, 0, 1, 10, 50, 100, or 200?M of aluminium chloride, at pH 4.5 for 4h (or 2h for comet assay) at room temperature, 25±1°C. Following treatment

V. Mohan Murali Achary; Suprava Jena; Kamal K. Panda; Brahma B. Panda

2008-01-01

241

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

242

LA MESURE DU COD DES ALLIAGES D'ALUMINIUM ; DIFFICULTS RENCONTRES POUR SA DTERMINATION  

E-print Network

661 LA MESURE DU COD DES ALLIAGES D'ALUMINIUM ; DIFFICULT�S RENCONTR�ES POUR SA D�TERMINATION P vue de mesurer le COD d'alliages d'aluminium ont d'abord montré que les recommandations britanniques à balayage des surfaces de rupture ; elles ont montré que le COD est très différent suivant que l

Paris-Sud XI, Université de

243

Phenomenon of Barrelling in Square Billets of Aluminium During Cold Upset Forging  

Microsoft Academic Search

Experiments were carried out to generate data on the upset forging of square billets of annealed aluminium. The measured curvatures\\u000a of the barrelled aluminium square billets were found to conform with calculated values using experimental data. The calculations\\u000a were made on the assumption that the curvature of the barrel followed the geometry of a circular arc. It was further found

K. Manisekar; R. Narayanasamy

2003-01-01

244

Kinetic Constraints in Acute Aluminium Toxicity in the Rainbow Trout ( Oncorhynchus mykiss )  

Microsoft Academic Search

We have designed a laboratory bioassay to expose fish to kinetically determined differences in aluminium hydroxide solution chemistry. We have used this system to demonstrate the hitherto unexpected result of an acute aluminium toxicity in the fish at a pH of 6.5. Supporting experiments have demonstrated that the mechanism of toxicity at this pH was probably an asphyxiation brought about

Christopher Exley; Alan J. Wicks; Rupert B. Hubert; Derek J. Birchall

1996-01-01

245

A TEM study of precipitation and related microstructures in friction-stir-welded 6061 aluminium  

Microsoft Academic Search

Residual microstructures, including dynamic recrystallization and grain growth structures and a wide range of precipitation phenomena associated with a friction-stir-weld in a thin 6061-T6 aluminium plate have been systematically investigated utilizing light metallography and transmission electron microscopy. In this rather remarkable process, a hard steel head pin rotating at 400 r.p.m. was advanced into a solid 6061-aluminium plate at a

L. E. MURR; G. LIU; J. C. McCLURE

1998-01-01

246

Effect of pulsed current welding on fatigue behaviour of high strength aluminium alloy joints  

Microsoft Academic Search

High strength aluminium alloys (Al–Zn–Mg–Cu alloys) have gathered wide acceptance in the fabrication of light weight structures requiring high strength-to weight ratio, such as transportable bridge girders, military vehicles, road tankers and railway transport systems. The preferred welding processes of high strength aluminium alloy are frequently gas tungsten arc welding (GTAW) process and gas metal arc welding (GMAW) process due

V. Balasubramanian; V. Ravisankar; G. Madhusudhan Reddy

2008-01-01

247

Broadened X-ray-diffraction profile analysis of cold-rolled aluminium-magnesium alloys  

Microsoft Academic Search

A cold-rolled, commercial pure aluminium and three aluminium-magnesium alloys (containing, respectively, 1 wt%, 3 wt% and 5 wt% magnesium) were studied by X-ray-diffraction (XRD) profile analysis. The investigated equivalent plastic deformations of the materials were ranged between 0.1 and 5.0. With increases in the amounts of magnesium, the diffraction peaks widened. For each alloy, the peak width (which gives first

N. Ji; J. L. Lebrun; P. Sainfort

1994-01-01

248

Immobilised molten salt membrane based magnesium sensor for aluminium-magnesium melts  

Microsoft Academic Search

Magnesium sensitive probes were constructed and tested in different melts of commercial aluminium-magnesium alloys. The probes\\u000a were composed of a porous magnesium oxide one closed end tube or thimble to which a magnesium conducting salt is impregnated.\\u000a The activity of magnesium in the aluminium-magnesium melt was determined with report to a pure magnesium reference contained\\u000a in the inside of the

J. Vangrunderbeek; J. Luyten; R. Stephen; F. De Schutter; L. Zhang; D. Fray

1995-01-01

249

On the precipitation of magnesium silicide in irradiated aluminium–magnesium alloys  

Microsoft Academic Search

Thermal neutron irradiation of aluminium or its alloys causes the production of silicon by transmutation. In aluminium–magnesium alloys, the transmutation-produced silicon reacts with magnesium and forms small precipitates. The precipitation in irradiated Al–Mg alloys is similar to the early stage of aging in thermally treated Al–Mg–Si alloys. This study evidences the simultaneous generation of two crystallographically different precipitate types. On

M. Verwerft

2000-01-01

250

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

2006-12-01

251

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

252

Anisotropic work-hardening behaviour ofstructural steels and aluminium alloys at large strains  

NASA Astrophysics Data System (ADS)

Sheet metal forming processes may often involve intense forming sequences, leading to large strains and severe strain-path changes. Optimizing such technologies requires a good understanding and description of the anisotropic plastic behaviour of the deformed material, in connection with the evolution of its texture and microstructure. In this paper, we present the predictions provided by a model involving isotropic and kinematioc hardening and by a physically-based microstructural model, which introduces additional internal variables taking into accounthe directional strength of dislocation structures and their polarity. These models have been identified by using sequences of uniaxial traction and simple shear experiments, carried out on various steels (DC06, DP600, HSLA340) and aluminium alloys (AA5182-O, AA6016-T4). The microstructural model proved able predict the complex hardening behaviour displayed, especially by the ferritic steels, namely the transient work-hardening stagnation during reversed deformation in Bauschinger tests, the temporary work-softening during orthogonal tests, and the grain fragmentation at large monotonie strains.

Bouvier, S.; Teodosiu, C.; Haddadi, H.; Tabacaru, V.

2003-03-01

253

Advanced phosphorus removal from membrane filtrates by adsorption on activated aluminium oxide and granulated ferric hydroxide.  

PubMed

The advanced phosphorus (P) removal by adsorption was studied for its suitability as a post-treatment step for membrane bioreactor (MBR) effluents low in P concentration and particle content. Two commercial adsorbents, granulated ferric hydroxide (GFH) and activated aluminium oxide (AA), were studied in batch tests and lab-scale filter tests for P adsorption in MBR filtrates. GFH showed a higher maximum capacity for phosphate and a higher affinity at low P concentrations compared to AA. Competition by inorganic ions was negligible for both adsorbents at the original pH (8.2). When equilibrium P concentrations exceeded 2 mg L(-1) in the spiked MBR filtrates, a precipitation of calcium phosphates occurred additionally to adsorption. During column studies the effluent criteria of 50 microgL(-1) P was reached after a throughput of 8000 bed volumes for GFH and 4000 for AA. Dissolved organic carbon appears to be the strongest competitor for adsorption sites. A partial regeneration and reloading of both adsorbents could be achieved by the use of sodium hydroxide. PMID:15325178

Genz, Arne; Kornmüller, Anja; Jekel, Martin

2004-09-01

254

Fatigue crack detection in a multi-riveted strap joint aluminium panel  

NASA Astrophysics Data System (ADS)

The scope of this paper is the investigation of reliable damage indicators obtained from Lamb wave responses on a multi-riveted strap joint aluminium panel representing a standard joint in aviation. Damage indices based on amplitude and cross-correlation are assessed by examining two data sets. The first set was taken 8 years ago, while the second set was obtained recently. The resumption of the experiment on the aircraft riveted panel after 8 years required a new clamping, a different data acquisition system and involved a new operator amongst other changes. Those variations inevitably caused deviations in the gathered data. The deviations obtained will be examined in the context of the derived damage indices. The application of a second baseline is carried out and its necessity discussed. Additional temperature measurements were recorded for the second phase of the experiment which showed high correlation with the variation of the waveforms and hence with the damage indices. This study gives a good indication of the sensitivity and reliability of a SHM system based on guided waves in complex joint structures. It also provides information about the robustness of the chosen method, as in real-world applications it is more likely that operators will change too.

Stolze, Frank; Staszewski, Wieslaw J.; Manson, Graeme; Worden, Keith

2009-03-01

255

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

2013-01-01

256

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

257

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

258

Influenceof aluminium precursor on physico-chemical properties of aluminium hydroxidesand oxides Part II. Al(ClO 4 ) 3 ·9H 2 O  

Microsoft Academic Search

Aluminium hydroxide was precipitated\\u000a during a hydrolysis of aluminium perchlorate in ammonia medium. The materials\\u000a were studied with the following methods: thermal analysis, IR spectroscopy,\\u000a X-ray diffraction, low-temperature nitrogen adsorption and adsorption–desorption\\u000a of benzene vapours.\\u000a \\u000a Freshly precipitated boehmite had a high value\\u000a of SBET=211 m2 g–1\\u000a determined from nitrogen adsorption, good sorption capacity for benzene vapours,\\u000a developed mesoporous structure and

Barbara Pacewska; Olga Kluk-P?osko?ska; D. Szychowski

2006-01-01

259

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

260

Use of DTA to determine the effect of mineralizers on the cement-quartz hydrothermal reactions. Part 2. Clay addition  

Microsoft Academic Search

The effect of adding up to 40% by weight of kaolinite and metakaolinite to cement-quartz mortars hydrothermally cured (autoclaved) at 175°C was investigated by DTA. It is evident that aluminium substitution in the CSH-I lattice takes place with the clay additions in a manner similar to that observed for gibbsite addition, as reported in the previous paper (Part 1, Thermochim.

A. Ray; E. R. Cantrill; M. G. Stevens; L. Aldridge

1995-01-01

261

Water defluoridation by aluminium oxide-manganese oxide composite material.  

PubMed

In this study, aluminium oxide-manganese oxide (AOMO) composite material was synthesized, characterized, and tested for fluoride removal in batch experiments. AOMO was prepared from manganese(II) chloride and aluminium hydroxide. The surface area of AOMO was found to be 30.7m2/g and its specific density was determined as 2.78 g/cm3. Detailed investigation of the adsorbent by inductively coupled plasma-optical emission spectrometry, inductively coupled plasma-mass spectrometry, and ion chromatography (for sulphate only) showed that it is composed of Al, Mn, SO4, and Na as major components and Fe, Si, Ca, and Mg as minor components. Thermogravimetric analysis was used to study the thermal behaviour of AOMO. X-ray diffraction analysis showed that the adsorbent is poorly crystalline. The point of zero charge was determined as 9.54. Batch experiments (by varying the proportion of MnO, adsorbent dose, contact time, initial F concentration, and raw water pH) showed that fluoride removal efficiency ofAOMO varied significantly with percentage of MnO with an optimum value of about I11% of manganese oxide in the adsorbent. The optimum dose of the adsorbent was 4 g/L which corresponds to the equilibrium adsorption capacity of 4.8 mg F-/g. Both the removal efficiency and adsorption capacity showed an increasing trend with an increase in initial fluoride concentration of the water. The pH for optimum fluoride removal was found to be in the range between 5 and 7. The adsorption data were analysed using the Freundlich, Langmuir, and Dubinirn-Radushkevich models. The minimum adsorption capacity obtained from the non-linear Freundlich isotherm model was 4.94 mg F-/g and the maximum capacity from the Langmuir isotherm method was 19.2mg F-/g. The experimental data of fluoride adsorption on AOMO fitted well to the Freundlich isotherm model. Kinetic studies showed that the adsorption is well described by a non-linear pseudo-second-order reaction model with an average rate constant of 3.1 x 10(-2) g/min mg. It is concluded that AOMO is a highly promising adsorbent for the removal of excess fluoride from drinking water. PMID:24956783

Alemu, Sheta; Mulugeta, Eyobel; Zewge, Feleke; Chandravanshi, Bhagwan Singh

2014-08-01

262

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

263

Derivation of a water quality guideline for aluminium in marine waters.  

PubMed

Metal risk assessment of industrialized harbors and coastal marine waters requires the application of robust water quality guidelines to determine the likelihood of biological impacts. Currently there is no such guideline available for aluminium in marine waters. A water quality guideline of 24?µg total Al/L has been developed for aluminium in marine waters based on chronic 10% inhibition or effect concentrations (IC10 or EC10) and no-observed-effect concentrations (NOECs) from 11 species (2 literature values and 9 species tested including temperate and tropical species) representing 6 taxonomic groups. The 3 most sensitive species tested were a diatom Ceratoneis closterium (formerly Nitzschia closterium; IC10?=?18?µg Al/L, 72-h growth rate inhibition) < mussel Mytilus edulis plannulatus (EC10?=?250?µg Al/L, 72-h embryo development) < oyster Saccostrea echinata (EC10?=?410?µg Al/L, 48-h embryo development). Toxicity to these species was the result of the dissolved aluminium forms of aluminate (Al(OH4 (-) ) and aluminium hydroxide (Al(OH)3 (0) ) although both dissolved, and particulate aluminium contributed to toxicity in the diatom Minutocellus polymorphus and green alga Dunaliella tertiolecta. In contrast, aluminium toxicity to the green flagellate alga Tetraselmis sp. was the result of particulate aluminium only. Four species, a brown macroalga (Hormosira banksii), sea urchin embryo (Heliocidaris tuberculata), and 2 juvenile fish species (Lates calcarifer and Acanthochromis polyacanthus), were not adversely affected at the highest test concentration used. Environ Toxicol Chem 2015;34:141-151. © 2014 SETAC. PMID:25318392

Golding, Lisa A; Angel, Brad M; Batley, Graeme E; Apte, Simon C; Krassoi, Rick; Doyle, Chris J

2015-01-01

264

Free radical scavengers & lipid peroxidation in acute aluminium phosphide poisoning.  

PubMed

Free radicals scavengers superoxide dismuatase (SOD) and catalase and lipid peroxidation were studied in 45 patients of aluminium phosphide poisoning irrespective of age and sex admitted to a hospital in north India during the January 1992 to December 1993. Serial serum superoxide dismutase (SOD), catalase and MDA (malonyldialdehyde) were estimated on days 1, 2 and 5 post-admission depending on the survival of the patients. Serum SOD levels were significantly higher (P < 0.001) but serum catalase was significantly lower (P < 0.001) in patients than controls (patients of peripheral circulatory failure and normals) on days 1 and 2 which suggested stimulation of SOD and inhibition of catalase by phosphine resulting in excessive hydrogen peroxide (H2O2) load. Significantly higher levels of MDA (P < 0.001) in patients than controls on days 1 and 2 indicated enhanced lipid peroxidation in this poisoning. Twenty four patients died constituting a mortality rate of 53.3 per cent. The significantly high levels of SOD and MDA in non-survivors suggested their direct relation to mortality while catalase levels had an inverse relationship. Return of SOD and catalase and MDA to normal or near normal levels in survivors by day 5 suggested abolition of an oxidative stress due to elimination of phosphine. PMID:8840658

Chugh, S N; Arora, V; Sharma, A; Chugh, K

1996-08-01

265

Evidence of superdense aluminium synthesized by ultrafast microexplosion  

PubMed Central

At extreme pressures and temperatures, such as those inside planets and stars, common materials form new dense phases with compacted atomic arrangements and unusual physical properties. The synthesis and study of new phases of matter at pressures above 100 GPa and temperatures above 104 K—warm dense matter—may reveal the functional details of planet and star interiors, and may lead to materials with extraordinary properties. Many phases have been predicted theoretically that may be realized once appropriate formation conditions are found. Here we report the synthesis of a superdense stable phase of body-centred-cubic aluminium, predicted by first-principles theories to exist at pressures above 380 GPa. The superdense Al phase was synthesized in the non-equilibrium conditions of an ultrafast laser-induced microexplosion confined inside sapphire (?-Al2O3). Confined microexplosions offer a strategy to create and recover high-density polymorphs, and a simple method for tabletop study of warm dense matter. PMID:21863012

Vailionis, Arturas; Gamaly, Eugene G.; Mizeikis, Vygantas; Yang, Wenge; Rode, Andrei V.; Juodkazis, Saulius

2011-01-01

266

Nano-crystalline P/M aluminium for automotive applications  

NASA Astrophysics Data System (ADS)

The reduction of total vehicle weight and lowering of moving masses within the engine are key elements to overcome future emission challenges of the automotive industry. Within a German BMBF funded project the melt spinning technology will be driven to a series production status. The very fast cooling condition of the melt leads to a nano-structure of the aluminium material. This results in new material properties of known alloys. The strength increases dramatically without lowered forming behaviour. With this process the freedom of designing complex alloys is very flexible. Different alloys have been investigated for several applications, where high strength at room and elevated temperatures and/or high wear resistance is required. This paper presents some results regarding the processing, microstructure and mechanical properties of a developed Al-Ni-Fe alloy. This joined research project with partners from the automotive industry as well as automotive suppliers and universities is funded by the German BMBF "NanoMobile" Program under Project number 03X3008.

Hummert, K.; Schattevoy, R.; Broda, M.; Knappe, M.; Beiss, P.; Klubberg, F.; Schubert, T. H.; Leuschner, R.

2009-01-01

267

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

268

Mechanism of stabilization of dicalcium silicate solid solution with aluminium.  

PubMed

Stoichiometric dicalcium silicate, Ca2SiO4, displays a well-known polymorphism with temperature. When this phase is doped by a range of elements, belite, one of the main phases of cements, is generated. Here, we thoroughly study the aluminum doping of dicalcium silicate. This type of study is important for cement characterization and also from a basic point of view. Ca2Si(1-2x)Al(2x)O(4-x)?(x) (x = 0, 0.010, 0.014, 0.03) has been prepared and studied by X-ray powder diffraction and the Rietveld method. The limiting composition has been established as Ca2Si0.972Al0.028O3.986?0.014. The (27)Al MAS NMR band located close to ~-70 ppm is ascribed to tetrahedral environments, in agreement with the proposed aliovalent Si/Al atomic substitution mechanism. Thermal analysis measurements under a wet atmosphere indirectly confirm the increase of oxygen vacancies as the amount of incorporated protons increases with the aluminium content. A thorough electrical characterization has been carried out including overall conductivity measurements under wet and dry atmospheres and conductivity as a function of the oxygen partial pressure. The samples show oxide anion conductivity with a small p-type electronic contribution under oxidizing conditions. These compounds display a very important proton contribution to the overall conductivities under humidified atmospheres. PMID:24292166

Cuesta, Ana; Aranda, Miguel A G; Sanz, Jesús; de la Torre, Angeles G; Losilla, Enrique R

2014-02-01

269

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. PMID:22534883

Page, Kathryn E.; White, Keith N.; McCrohan, Catherine R.

2013-01-01

270

Mackay icosahedron explaining orientation relationship of dispersoids in aluminium alloys.  

PubMed

The orientation relations (ORs) of the cubic icosahedral quasicrystal approximant phase ?-Al(Fe,Mn)Si have been studied after low temperature annealing of a 3xxx wrought aluminium alloy by transmission electron microscopy. From diffraction studies it was verified that the most commonly observed OR for the ?-Al(Fe,Mn)Si dispersoids is [1\\bar 11]? // [1\\bar 11]Al, (5\\bar 2\\bar 7)? // (011)Al. This orientation could be explained by assuming that the internal Mackay icosahedron (MI) in the ?-phase has a fixed orientation in relation to Al, similar to that of the icosahedral quasi-crystals existing in this alloy system. It is shown that mirroring of the normal-to-high-symmetry icosahedral directions of the MI explains the alternative orientations, which are therefore likely to be caused by twinning of the fixed MI. Only one exception was found, which was related to the Bergman icosahedron internal to the T-phase of the Al-Mg-Zn system. PMID:25274523

Muggerud, Astrid Marie F; Li, Yanjun; Holmestad, Randi; Andersen, Sigmund J

2014-10-01

271

[Food additives and healthiness].  

PubMed

Additives are used for improving food structure or preventing its spoilage, for example. Many substances used as additives are also naturally present in food. The safety of additives is evaluated according to commonly agreed principles. If high concentrations of an additive cause adverse health effects for humans, a limit of acceptable daily intake (ADI) is set for it. An additive is a risk only when ADI is exceeded. The healthiness of food is measured on the basis of nutrient density and scientifically proven effects. PMID:24772784

Heinonen, Marina

2014-01-01

272

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 PMID:13932137

McLaughlin, A. I. G.; Kazantzis, G.; King, E.; Teare, Donald; Porter, R. J.; Owen, R.

1962-01-01

273

Effect of atomic parameters on determination of aluminium abundance in atmospheres of late-type stars  

NASA Astrophysics Data System (ADS)

We study the effect of the photoionization cross sections for the ground state of Al I on the inferred aluminium abundance in stellar atmospheres. We match the theoretical and observed line profiles of the resonance ?? 3944.01, 3961.52 Å and subordinate ?? 6696.03, 6698.68 Å doublets in high-resolution spectra of the metal-poor solar-type stars HD22879 and HD201889. We determine the parameters of these stars from their photometric and spectroscopic data. Our computations show that the profiles can be matched and a single aluminium abundance inferred simultaneously from both groups of spectral lines only with low photoionization cross sections (about 10-12 Mb). Larger cross sections (about 58-65 Mb) make such fits impossible. We therefore conclude that small photoionization cross sections should be preferred for the determination of aluminium abundances in metal-poor stars. We redetermine the aluminium abundances in the atmospheres of halo stars. The resulting abundances prove to be lower by 0.1-0.15 dex than our earlier determinations which does not affect the conclusions based on our earlier estimates. In particular, the NLTE [Al/Fe]-[Fe/H] dependence, on the whole, agrees only qualitatively with the results of theoretical predictions. Therefore further refinement of the theory of nuclear synthesis of aluminium in the process of the chemical evolution of the Galaxy remains a task of current importance.

Menzhevitski, V. S.; Shimanskaya, N. N.; Shimansky, V. V.; Kudryavtsev, D. O.

2014-04-01

274

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

SciTech Connect

Aluminium doped barium and strontium hexaferrite nanoparticles BaAl {sub x}Fe{sub (12-x)}O{sub 19} and SrAl {sub x}Fe{sub (12-x)}O{sub 19} 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 ferrite with structure retention, whereas strontium aluminium ferrites could be produced with any aluminium content including total substitution of the iron. All synthesised materials consisted of particles smaller than 1 {mu}m, which is the size of a single magnetic domain, and various doping levels were achieved with the final elemental composition being within the bounds of experimental error. The materials show structural and morphological changes as they move from iron to aluminium ferrites. Such materials may be promising for imaging applications.

Shirtcliffe, Neil J. [Nottingham Trent University, Clifton Lane, Clifton, Nottingham NG11 8NS (United Kingdom)]. E-mail: neil.shirtcliffe@ntu.ac.uk; Thompson, Simon [Nottingham Trent University, Clifton Lane, Clifton, Nottingham NG11 8NS (United Kingdom); O'Keefe, Eoin S. [QinetiQ, Farnborough, Hampshire (United Kingdom); Appleton, Steve [QinetiQ, Farnborough, Hampshire (United Kingdom); Perry, Carole C. [Nottingham Trent University, Clifton Lane, Clifton, Nottingham NG11 8NS (United Kingdom)]. E-mail: carole.perry@ntu.ac.uk

2007-02-15

275

The role of VuMATE1 expression in aluminium-inducible citrate secretion in rice bean (Vigna umbellata) roots.  

PubMed

Aluminium (Al)-activated citrate secretion plays an important role in Al resistance in a number of plant species, such as rice bean (Vigna umbellata). This study further characterized the regulation of VuMATE1, an aluminium-activated citrate transporter. Al stress induced VuMATE1 expression, followed by the secretion of citrate. Citrate secretion was specific to Al stress, whereas VuMATE1 expression was not, which could be explained by a combined regulation of VuMATE1 expression and Al-specific activation of VuMATE1 protein. Pre-treatment with a protein translation inhibitor suppressed VuMATE1 expression, indicating that de novo biosynthesis of proteins is required for gene expression. Furthermore, post-treatment with a protein translation inhibitor inhibited citrate secretion, indicating that post-transcriptional regulation of VuMATE1 is critical for citrate secretion. Protein kinase and phosphatase inhibitor studies showed that reversible phosphorylation was important not only for transcriptional regulation of VuMATE1 expression but also for post-translational regulation of VuMATE1 protein activity. These results suggest that citrate secretion is dependent on both transcriptional and post-transcriptional regulation of VuMATE1. Additionally, VuMATE1 promoter-?-glucuronidase fusion lines revealed that VuMATE1 expression was restricted to the root apex and was entirely Al induced, indicating the presence of cis-acting elements regulating root tip-specific and Al-inducible gene expression, which will be an important resource for genetic improvement of plant Al resistance. PMID:23408830

Liu, Mei Ya; Chen, Wei Wei; Xu, Jia Meng; Fan, Wei; Yang, Jian Li; Zheng, Shao Jian

2013-04-01

276

Addition and Subtraction  

NSDL National Science Digital Library

Welcome students, Using this website, you can play fun and interactive games and print out fun worksheets that will help you practice addition and subtraction. Please explore the website and print out as many worksheets as you would like. Print out and answer the problems on this worksheet. Addition and Subtraction Worksheet This game is for more advanced students in addition and subtraction. Figure out what sign to put in between the numbers to make the combination on the right. Advanced Add and Subtract Game This fun animal game will help you practice your addition and subtraction. Farm Animal Game Print ...

Ms. Roberts

2011-04-20

277

Reduction of bioavailability of aluminium in neonatal parenteral nutrition solutions by prior complexation in the dosage form.  

PubMed

Aluminium (Al ) is abundant in our environment and is a contaminant of electrolyte solutions used in the manufacture of Total Parenteral Nutrition (TPN) solutions administered to neonates, who are unable to tolerate oral feeding. Previous studies by McHalsky et al. (1) have shown concern over the levels of aluminium in parenteral products, and there are special considerations needed with regard to neonatal TPN solutions, (2). It is felt that neurotoxicology and abnormalities of bone histology may be seen with aluminium deposition in the tissues. In the present study it was shown that the average aluminium contamination in TPN solutions was in the order of 205 micrograms/L. It is well documented that aluminium is chelated successfully in dialysis solutions by desferrioxamine (DFO), Allain et al. (3). Using an AA spectrophotometer equipped with a graphite furnace, the average amount of aluminium in compounded neonatal TPN solutions was determined. Equimolar amounts of DFO to aluminium were added to various neonatal TPN formulations, and the physical stability of each solution was determined using microscopic and electronic particle counting analysis. This study suggests that aluminium can be irreversibly chelated with DFO and stable TPN solutions can be prepared. PMID:1432456

Hayes, P; Martin, T P; Pybus, J; Hunt, J; Broadbent, R S

1992-01-01

278

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

279

Focused ion beam (FIB) etching to investigate aluminium-coated polymer laminates subjected to heat and moisture loads  

Microsoft Academic Search

Multilayered aluminium-coated polymer laminates are the common barrier envelopes of vacuum insulation panels used as high performance thermal insulation in building applications. These laminates are made of up to ten distinct layers including three aluminium barrier layers applied by vacuum web coating. During their expected lifetime, which is required to last longer than 20 years, they will be subjected to heat

S. Brunner; P. J. Tharian; H. Simmler; K. Ghazi Wakili

2008-01-01

280

The friction and wear of Kevlar 49 sliding against aluminium at low velocity under high contact pressures  

Microsoft Academic Search

The friction and wear behaviour of Kevlar 49 sliding against aluminium under large contact pressures at low sliding velocities was examined. Kevlar 49 on aluminium friction is measured using yarns on capstans, and compared with literature results for Kevlar 49 on itself. A modified version of Howell's equation is presented in terms of stresses, ?=a??, to allow finite element modelling

I. F Brown; C. J Burgoyne

1999-01-01

281

The development of the welding procedures and fatigue of butt-welded structures of aluminium-AA5383  

Microsoft Academic Search

The development of the aluminium shipbuilding industry has seen greater demands put upon the design of faster and larger vessels, particularly in the high speed ferry industry, and increasing loads put on existing vessels. Because of this the fatigue performance of marine grade aluminium alloys has become a limiting factor for design, especially with regard to severe service conditions. Far

R. C Calcraft; M. A Wahab; D. M Viano; G. O Schumann; R. H Phillips; N. U Ahmed

1999-01-01

282

Mössbauer and X-ray diffraction study of an aluminium-magnesium-silicon alloy containing Pb and Sn  

Microsoft Academic Search

The Mössbauer parameters of tin in aluminium matrix were studied and published in an earlier paper1. The aim of this work was to carry out investigations on tin in an aluminium alloy containing magnesium, silicon and lead beside the Mössbauer active tin. The effect of heat treatments on the formation of intermetallic compounds was studied by X-ray diffraction and by

A. Vértes; T. Turmezey; Á. Griger; M. Z. Awad; S. Nagy

1984-01-01

283

Corrosion behaviour of a surface-treated AISI H11 hot work tool steel in molten aluminium alloy  

Microsoft Academic Search

Immersion tests in a molten aluminium alloy of a surface-treated AISI H11 hot work tool steel were carried out in order to study the corrosion mechanisms and the effect of different surface treatments on the resistance of the material. The steel has a great reactivity with molten aluminium, which causes a generalised attack on the exposed surface. Plasma nitriding and

A. Molinari; M. Pellizzari; G. Straffelini; M. Pirovano

2000-01-01

284

DFT study on the interaction between monomeric aluminium and chloride ion in aqueous solution.  

PubMed

The interaction of monomeric aluminium and chloride ion in aqueous solution is investigated by density functional theory (DFT) calculations. The computational results show that it is difficult for Cl(-) to enter the inner-coordination shell of aluminium complexes by replacing the bound water molecules, independent of pH and the concentration of Cl(-). However, pH and the concentration of Cl(-) might influence the conformations, bond lengths and natural charge populations of monomeric aluminium complexes to a given extent. Based on the computed Gibbs energies, pK(a) values of various hydrolysis species in the presence and absence of Cl(-) are evaluated, respectively. It is concluded that pK(a) increases with the introduction of Cl(-). PMID:21451819

Jin, Xiaoyan; Yang, Wenjing; Qian, Zhaosheng; Wang, Yingjie; Bi, Shuping

2011-05-14

285

Evaluation Of Four Welding Arc Processes Applied To 6061 Aluminium Alloy  

SciTech Connect

At a time when greenhouse gas emissions must be reduced, the use of the aluminium alloys is expanding, in particular in the transportation industry. In order to extend the possibilities of aluminium assembly design, new Metal Inert Gas (MIG) welding processes have been conceived. They work at lower temperatures than usual arc processes (classic MIG or Tungsten Inert Gas). This study compares four arc welding processes, applied to the 6061 aluminium alloy. These four weld processes have been studied through the metallurgical analysis of the weld beads. Metallography, micro-hardness testings, X Ray radiography have been carried out on the produced weld beads. The processes are classified according to the quality of the beads like geometry of beads, size of the heat affected zone and presence of defects.

Benoit, A. [Univ Paris-Sud, Laboratoire de Physico-Chimie de l'Etat Solide, UMR 8182, 91405 Orsay, F-91405 (France); Laboratoire de Genie des Materiaux et Procedes Associes (LGMPA), Ecole Polytechnique de l'Universite de Nantes, Nantes Atlantique Universites, rue Christian Pauc, BP 50609, 44306 Nantes Cedex 3 (France); Paillard, P. [Laboratoire de Genie des Materiaux et Procedes Associes (LGMPA), Ecole Polytechnique de l'Universite de Nantes, Nantes Atlantique Universites, rue Christian Pauc, BP 50609, 44306 Nantes Cedex 3 (France); Baudin, T. [Univ Paris-Sud, Laboratoire de Physico-Chimie de l'Etat Solide, UMR 8182, 91405 Orsay, F-91405 (France); CNRS, Orsay, F-91405 (France); Jobez, S.; Castagne, J.-F. [SNECMA-Usine d'Evry-Corbeil Snecma Evry-Corbeil-Route Henri Auguste Desbrueres-91000 Evry (France)

2011-01-17

286

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. PMID:3260886

Crampton, J R; Gibbons, L C; Rees, W D

1988-01-01

287

Towards the structure of rare earth luminescence centres - terbium doped aluminium nitride as an example system  

NASA Astrophysics Data System (ADS)

Sputter deposited terbium doped aluminium nitride layers were investigated with respect to the distribution and surroundings of the terbium luminescence ions. Semi-empirical calculations indicate that terbium forms complexes consisting of one aluminium vacancy surrounded by three oxygen ions on nitrogen lattice positions and one nitrogen ion that is bound to a terbium ion on a distorted aluminium lattice position. The crystal field splitting of the terbium ions indicate their surroundings to be not tetrahedral but, as anticipated from the determined complex, C3v. Complementary electron microscopic investigations show a random distribution of these complexes within the layer volume. The terbium ions cause a shape of the Tb M5,4 edge similar to the shapes in other ionic compounds like Tb2O3.

Benz, Felix; Walther, Thomas; Strunk, Horst P.

2013-11-01

288

Carbamate deposit control additives  

SciTech Connect

Deposit control additives for internal combustion engines are provided which maintain cleanliness of intake systems without contributing to combustion chamber deposits. The additives are poly(oxyalkylene) carbamates comprising a hydrocarbyloxyterminated poly(Oxyalkylene) chain of 2-5 carbon oxyalkylene units bonded through an oxycarbonyl group to a nitrogen atom of ethylenediamine.

Honnen, L.R.; Lewis, R.A.

1980-11-25

289

Lead and aluminium levels in infants' hair, diet, and the local environment in the Moroccan city of Marrakech.  

PubMed

In order to assess the contamination burden of infants from the city of Marrakech (Morocco), hair lead and aluminium concentrations were studied in a sample of 573 infants, aged 0 to 12 months, and correlated with the infants descriptors such as age, gender and the parents occupations. Moreover, the two metals were measured in the local environment (soil, drinking water) and in the food commonly used during weaning. The mean values in children's hair are 6.6 and 9.5 microg/g for lead and aluminium respectively. The higher value for aluminium compared with lead can be explained by the higher levels of aluminium available in both the infant food and the environment. Age, gender, and the parents' occupations influenced significantly lead but not aluminium contents. PMID:17363036

Zaida, Farida; Chadrame, Souad; Sedki, Azeddine; Lekouch, Nadra; Bureau, François; Arhan, Pierre; Bouglé, Dominique

2007-05-15

290

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

2008-03-17

291

Severe myocardial depression in a patient with aluminium phosphide poisoning: a clinical, electrocardiographical and histopathological correlation.  

PubMed

Aluminium phosphide poisoning is very common in India. It is one of the most fatal poisons. The clinical spectrum of poisoning varies depending upon the dosage and duration of consumption. The main effect of the poison is due to the release of phosphine which inhibits cytochrome oxidase and thereby hampers cellular oxygen utilization. Almost any organ can be affected by aluminium phosphide poisoning. We report a case where the heart was the predominantly affected organ. We describe the clinical symptoms and signs and their correlation with electrocardiographic and histopathological examinations. PMID:19881181

Shah, Viral; Baxi, Seema; Vyas, Tanmay

2009-01-01

292

Severe reversible myocardial injury associated with aluminium phosphide toxicity: A case report and review of literature  

PubMed Central

Aluminium phosphide is commonly used as an insecticide and can be toxic to humans at the cellular level by interfering with mitochondrial energy metabolism. We report on three cases of severe aluminium phosphide cardio-toxicity, resulting in severe decrease in both ventricular heart functions. The first case succumbed to intractable ventricular arrhythmias complicated by multi-organ failure before she died; while the other two cases required invasive hemodynamic support and eventually improved over the course of 10–14 days. We describe our experience and the challenges faced while managing one of them. PMID:25278724

Elabbassi, Wael; Chowdhury, Mohammed Andaleeb; Fachtartz, Arif Al Nooryani

2013-01-01

293

Aluminium transfer in bicarbonate dialysis using a sorbent regenerative system: an in vitro study.  

PubMed

Because of the known presence of aluminium oxide in the Redy cartridge and the increased solubility of aluminium (A1) in alkaline solution, an in vitro study was performed to measure the release of A1 from the Redy cartridge and its potential transfer across a dialyser membrane. The use of bicarbonate rinsed Redy cartridges was associated with significant release of A1 and its subsequent transfer across the cellulose acetate membrane. Bicarbonate dialysis with the Redy system is not recommended for maintenance haemodialysis. PMID:7243771

Branger, B; Ramperez, P; Marigliano, N; Mion, H; Shaldon, S; Mion, C

1980-01-01

294

Analysis of cutting forces during dry turning processes of UNS A92024-T3 aluminium bars  

NASA Astrophysics Data System (ADS)

In the aeronautical and aerospace industries there is a great demand of materials with high resistance and low weight such as the aluminium alloys for the production of different elements that conforms the airships and aerospace vehicles. In this work, an experimental study was carried out in order to analyse the influence of the cutting parameters (feed rate, cutting speed and type of tool) on the forces generated during dry turning tests of UNS A92024-T3 aluminium bars. The main influents factors on the forces were the feed rate and the interaction between type of tool and the spindle speed.

de Agustina, B.; Rubio, E. M.

2012-04-01

295

Awesome Addition Games  

NSDL National Science Digital Library

These games are fun to play and will test your addition skills! Click on the links to play the games! Play in the Kitten Match and test your math skills!! Pick the grade level you want to play on. Then pick numbers that add up to equal the number that they give you. Hurry, you're being timed! Use your addition skills to win a Diaper Derby!! First decide what you want your baby to look like! Then perform the addition problem that ...

Smith, Ms.

2010-10-14

296

Color Chips - Addition  

NSDL National Science Digital Library

This virtual manipulative provides students with practice adding positive and negative integers. Students are given an addition problem, and using one-to-one correspondence, the student is able to see what happens when adding negative integers. The addition problems can be computer generated or teacher generated and there is a free play mode which allows the student to practice with the chips and become familiar with the process of moving the chips around the page, and creating a visual representation of an addition problem with integers.

Utah State University

2011-06-28

297

Polyimide processing additives  

NASA Technical Reports Server (NTRS)

A process for preparing polyimides having enhanced melt flow properties is described. The process consists of heating a mixture of a high molecular weight poly-(amic acid) or polyimide with a low molecular weight amic acid or imide additive in the range of 0.05 to 15 percent by weight of additive. The polyimide powders so obtained show improved processability, as evidenced by lower melt viscosity by capillary rheometry. Likewise, films prepared from mixtures of polymers with additives show improved processability with earlier onset of stretching by TMA.

Fletcher, James C. (inventor); Pratt, J. Richard (inventor); St.clair, Terry L. (inventor); Stoakley, Diane M. (inventor); Burks, Harold D. (inventor)

1992-01-01

298

Smog control fuel additives  

SciTech Connect

A method is described of controlling, reducing or eliminating, ozone and related smog resulting from photochemical reactions between ozone and automotive or industrial gases comprising the addition of iodine or compounds of iodine to hydrocarbon-base fuels prior to or during combustion in an amount of about 1 part iodine per 240 to 10,000,000 parts fuel, by weight, to be accomplished by: (a) the addition of these inhibitors during or after the refining or manufacturing process of liquid fuels; (b) the production of these inhibitors for addition into fuel tanks, such as automotive or industrial tanks; or (c) the addition of these inhibitors into combustion chambers of equipment utilizing solid fuels for the purpose of reducing ozone.

Lundby, W.

1993-06-29

299

Additive Manufacturing Infrared Inspection  

NASA Technical Reports Server (NTRS)

Additive manufacturing is a rapid prototyping technology that allows parts to be built in a series of thin layers from plastic, ceramics, and metallics. Metallic additive manufacturing is an emerging form of rapid prototyping that allows complex structures to be built using various metallic powders. Significant time and cost savings have also been observed using the metallic additive manufacturing compared with traditional techniques. Development of the metallic additive manufacturing technology has advanced significantly over the last decade, although many of the techniques to inspect parts made from these processes have not advanced significantly or have limitations. Several external geometry inspection techniques exist such as Coordinate Measurement Machines (CMM), Laser Scanners, Structured Light Scanning Systems, or even traditional calipers and gages. All of the aforementioned techniques are limited to external geometry and contours or must use a contact probe to inspect limited internal dimensions. This presentation will document the development of a process for real-time dimensional inspection technique and digital quality record of the additive manufacturing process using Infrared camera imaging and processing techniques.

Gaddy, Darrell

2014-01-01

300

Phenylethynyl Containing Reactive Additives  

NASA Technical Reports Server (NTRS)

Phenylethynyl containing reactive additives were prepared from aromatic diamine, containing phenylethvnvl groups and various ratios of phthalic anhydride and 4-phenylethynviphthalic anhydride in glacial acetic acid to form the imide in one step or in N-methyl-2-pvrrolidinone to form the amide acid intermediate. The reactive additives were mixed in various amounts (10% to 90%) with oligomers containing either terminal or pendent phenylethynyl groups (or both) to reduce the melt viscosity and thereby enhance processability. Upon thermal cure, the additives react and become chemically incorporated into the matrix and effect an increase in crosslink density relative to that of the host resin. This resultant increase in crosslink density has advantageous consequences on the cured resin properties such as higher glass transition temperature and higher modulus as compared to that of the host resin.

Connell, John W. (Inventor); Smith, Joseph G., Jr. (Inventor); Hergenrother, Paul M. (Inventor)

2002-01-01

301

Phenylethynyl Containing Reactive Additives  

NASA Technical Reports Server (NTRS)

Phenylethynyl containing reactive additives were prepared from aromatic diamines containing phenylethynyl groups and various ratios of phthalic anhydride and 4-phenylethynylphthalic anhydride in glacial acetic acid to form the imide in one step or in N-methyl-2-pyrrolidi none to form the amide acid intermediate. The reactive additives were mixed in various amounts (10% to 90%) with oligomers containing either terminal or pendent phenylethynyl groups (or both) to reduce the melt viscosity and thereby enhance processability. Upon thermal cure, the additives react and become chemically incorporated into the matrix and effect an increase in crosslink density relative to that of the host resin. This resultant increase in crosslink density has advantageous consequences on the cured resin properties such as higher glass transition temperature and higher modulus as compared to that of the host resin.

Connell, John W. (Inventor); Smith, Joseph G., Jr. (Inventor); Hergenrother, Paul M. (Inventor)

2002-01-01

302

The formation of nanoporous membranes from anodically oxidized aluminium and their application to Li rechargeable batteries  

Microsoft Academic Search

A method for the preparation of nanoporous dielectric membranes from anodically oxidized aluminium is described. Pores of an initially formed free anodic alumina film were protected with gelatin gel, and the oxide barrier layer was chemically dissolved from bottom side of the film. The method is advantageous in that it permits complete removal of the barrier layer and fabrication of

A. Mozalev; S. Magaino; H. Imai

2001-01-01

303

The influence of porosity and morphology of hydrated oxide films on epoxy-aluminium bond durability  

Microsoft Academic Search

Clad aluminium alloy was pretreated by immersion in boiling water for times ranging between 30 s and 4 h. The chemical and physical properties of the films produced in the 100°C water were characterized by techniques including X-ray photoelectron spectroscopy (XPS), Rutherford backscattering spectroscopy (RBS), scanning electron microscopy (SEM), and secondary ion mass spectrometry (SIMS). The durability of the bonds

Andrew N. Rider

2001-01-01

304

Process Simulation of Aluminium Sheet Metal Deep Drawing at Elevated Temperatures  

SciTech Connect

Lightweight design is essential for an economic and environmentally friendly vehicle. Aluminium sheet metal is well known for its ability to improve the strength to weight ratio of lightweight structures. One disadvantage of aluminium is that it is less formable than steel. Therefore complex part geometries can only be realized by expensive multi-step production processes. One method for overcoming this disadvantage is deep drawing at elevated temperatures. In this way the formability of aluminium sheet metal can be improved significantly, and the number of necessary production steps can thereby be reduced. This paper introduces deep drawing of aluminium sheet metal at elevated temperatures, a corresponding simulation method, a characteristic process and its optimization. The temperature and strain rate dependent material properties of a 5xxx series alloy and their modelling are discussed. A three dimensional thermomechanically coupled finite element deep drawing simulation model and its validation are presented. Based on the validated simulation model an optimised process strategy regarding formability, time and cost is introduced.

Winklhofer, Johannes; Trattnig, Gernot [Virtual Vehicle Kompetenzzentrum-Das Virtuelle Fahrzeug Forschungsgesellschaft mbH (vif) Inffeldgasse 21/A/I 8010 Graz Austria (Austria); Lind, Christoph [SAG Alutech GmbH 5651 Lend Nr.25 (Austria); Sommitsch, Christof [Institute for Materials Science and Welding/Graz University of Technology Kopernikusgasse 24 8010 Graz (Austria); Feuerhuber, Hannes [weba Werkzeugbau Betriebs GmbH Weba-Strasse 2 4407 Dietach (Austria)

2010-06-15

305

Phosphine analysis in post mortem specimens following ingestion of aluminium phosphide.  

PubMed

Phosphine was detected in post mortem stomach and contents, blood, and liver specimens of a man who had ingested tablets containing aluminium phosphide. The phosphine was released from the samples after acid treatment and analysed by means of a headspace gas chromatographic technique using a nitrogen phosphorus detector. PMID:6314042

Chan, L T; Crowley, R J; Delliou, D; Geyer, R

1983-01-01

306

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

PubMed

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 in a 28-year-old man who had ingested a lethal amount (12 g) of aluminium phosphide with suicidal intent and was admitted to hospital approximately 6 hours postingestion. The patient had signs and symptoms of severe toxicity, and his clinical course included metabolic acidosis and liver dysfunction. Treatment consisted of gastric lavage with potassium permanganate solution, oral administration of charcoal and sorbitol suspension, intravenous administration of sodium bicarbonate, magnesium sulphate and calcium gluconate, and oral administration of sodium bicarbonate and coconut oil. Conservative and supportive therapy in the Intensive Care Unit was also provided. The patient survived following rapid treatment and supportive care. It is concluded that coconut oil has a positive clinical significance and can be added to the treatment protocol of acute aluminium phosphide poisoning in humans. PMID:15957538

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

2005-04-01

307

Corrosion inhibition and adsorption behaviour of Ocimum basilicum extract on aluminium  

Microsoft Academic Search

Purpose – To appraise the inhibiting effect of Ocimum basilicum extract on aluminium corrosion in 2 M HCl and 2 M KOH solutions, respectively, at 30 and 60°C. Design\\/methodology\\/approach – Corrosion rates were determined using the gas-volumetric technique and the values obtained in absence and presence of extract was used in calculation of the inhibition efficiency. The mechanism of inhibition

E. E. Oguzie; A. I. Onuchukwu; P. C. Okafor; E. E. Ebenso

2006-01-01

308

The adsorption and corrosion inhibition of anion surfactants on aluminium surface in hydrochloric acid  

Microsoft Academic Search

The adsorption and corrosion inhibition of the anion surfactants such as Dodecyl Sulphonic Acid Sodium Salt (DSASS), Dodecyl Benzene Sulfonic Acid Sodium Salt (DBSASS) and Sodium Dodecyl Sulfate (SDS) on the aluminium surface in hydrochloric acid solution was studied using the weight loss method. It was found that the adsorption of surfactants could prevent aluminum from weight loss and the

Tianpei Zhao; Guannan Mu

1999-01-01

309

A Real time predictive maintenance system of Aluminium Electrolytic Capacitors used in  

E-print Network

A Real time predictive maintenance system of Aluminium Electrolytic Capacitors used and a predictive maintenance system of an electrolytic capacitor used in Uninterrupted Power Supplies (UPS) and the capacitance C values of the electrolytic capacitors. Simulation and experimental results are presented

Paris-Sud XI, Université de

310

APPLICATION OF MAGNETIC PULSE WELDING FOR ALUMINIUM ALLOYS AND SPCC STEEL SHEET JOINTS  

Microsoft Academic Search

The magnetic pulse welding (MPW) is a cold weld process of conductive metals to the similar or dissimilar material. MPW uses magnetic pressure to drive the primary metal against the target metal sweeping away surface contaminants while forcing intimate metal-to- metal contact, thereby producing a solid-state weld. In this paper the MPW method and its application for several aluminium alloy

Tomokatsu Aizawa; Mehrdad Kashani; Keigo Okagawa

311

Diffusion bonding of aluminium oxide to stainless steel using stress relief interlayers  

Microsoft Academic Search

Aluminium oxide was diffusion bonded to AISI 304 steel using Ti, Cu or Mo as interlayer materials. It was observed that Ti joins easily to both ceramic and steel parts, giving an average shear strength equal to 20 MPa. However, within the experimental conditions applied, the adhesion between Al2O3 and Cu or Mo was unsuccessful. A finite element modelling (FEM)

Dilermando Travessa; Maurizio Ferrante; Gert den Ouden

2002-01-01

312

Cement & Concrete Science Conference: Leeds, 2009 Hydration of alite containing aluminium  

E-print Network

Cement & Concrete Science Conference: Leeds, 2009 Hydration of alite containing aluminium Begarin in cement is tricalcium silicate which leads during its hydration to the nucleation and growth of calcium silicate hydrate (referred to C-S-H (CaO)x-SiO2-(H2O)y). The development of this hydrate around the cement

Paris-Sud XI, Université de

313

Agronomic use of calcined christmas island iron\\/aluminium phosphates i. field trials  

Microsoft Academic Search

Christmas Island “C” ore when calcined at 550°C contains up to 24% aluminium and iron and 15% phosphorus which is not water-soluble but is up to 95% soluble in neutral ammonium citrate. Samples vary in total phosphorus content and in the percentage of phosphorus soluble in neutral ammonium citrate, depending on the proportions of crandallite, millisite, and apatite in the

F. B. Muller

1970-01-01

314

Parametric studies of the process of friction spot stir welding of aluminium 6060-T5 alloys  

Microsoft Academic Search

The friction stir welding is a process which made improvement in the light construction industries. The application of this new process lies in the capacity to assemble alloys of aluminium and more obviously with alloys which are not easily weldable alloys by the traditional processes. In our study, we centered the tests on the description of the significant parameters of

Mohamed Merzoug; Mohamed Mazari; Lahcene Berrahal; Abdellatif Imad

2010-01-01

315

Microstructures in the 6060 aluminium alloy after various severe plastic deformation treatments  

Microsoft Academic Search

This paper presents the results concerning the microstructural refinement of the industrial 6060 aluminium alloy processed by severe plastic deformation (SPD). The high level of plastic deformation was achieved using the three methods: hydrostatic extrusion (HE), equal channel angular extrusion (ECAE) and extrusion torsion (ET), which differed in the dynamics of the loading, intensity and homogeneity of the plastic strain

Bogus?awa Adamczyk-Cie?lak; Jaros?aw Mizera; Krzysztof Jan Kurzyd?owski

2011-01-01

316

Effect of friction stir lap welding conditions on joint strength of aluminium alloy 6060  

Microsoft Academic Search

Strength of lap joints made by friction stir welding (FSW) depends strongly on how material flows forming the weld nugget zone during FSW and also on how the joint is loaded during testing. Understanding of this processing-property relationship is currently inadequate. In this study, the effects of pin length, welding speed and rotation rate on weld strength using aluminium alloy

S. Yazdanian; Z. W. Chen

2009-01-01

317

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

318

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

319

High cycle fatigue damage mechanisms in cast aluminium subject to complex loads  

E-print Network

behaviour, and more specifically the fatigue damage mechanisms observed under complex loading conditionsHigh cycle fatigue damage mechanisms in cast aluminium subject to complex loads Imade Koutiria in "International Journal of Fatigue 47 (2013) 44-57" DOI : 10.1016/j.ijfatigue.2012.07.008 #12;loading conditions

Paris-Sud XI, Université de

320

Mechanical testing of titanium / aluminium-silicon interfaces by push-out O. Dezellusa,  

E-print Network

11 Mechanical testing of titanium / aluminium-silicon interfaces by push-out O. Dezellusa, , L; Titanium; Interface 1 Introduction Among the different ways used for processing high performance structural or automotive components with titanium or titanium alloys inserts [1;2]. When using conventional die casting

Boyer, Edmond

321

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

Microsoft Academic Search

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

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

1998-01-01

322

The embedded-atom model applied to vacancy formation in bulk aluminium and lithium  

Microsoft Academic Search

The embedded-atom model (EAM) is applied to the study of vacancy formation in bulk aluminium and lithium. A systematic study is undertaken into the sensitivity of the EAM potentials and embedding energy functionals as a function of the unrelaxed vacancy formation energy which is normally obtained via ab initio density functional calculations. The effect of this `empirical' input parameter on

P. M. Derlet; R. Høier; R. Holmestad; K. Marthinsen; N. Ryum

1999-01-01

323

Surface acoustic wave devices based on nanocrystalline diamond and aluminium nitride  

Microsoft Academic Search

Due to its high-acoustic velocity, diamond, when combined with piezoelectric material, has a promising potentiality for high frequency surface acoustic wave (SAW) devices. In the present work, low-surface roughness nanocrystalline diamond (NCD) were deposited on silicon substrate by microwave plasma assisted chemical vapour deposition process and piezoelectric aluminium nitride films were grown by DC reactive magnetron sputtering. For the first

F. Bénédic; M. B. Assouar; F. Mohasseb; O. Elmazria; P. Alnot; A. Gicquel

2004-01-01

324

Corrosion of Aluminium in Composite Cements Anthony Setiadi* and Neil B. Milestone  

E-print Network

Corrosion of Aluminium in Composite Cements Anthony Setiadi* and Neil B. Milestone Immobilisation they are economic, durable and have long-term stability. However, there may be issues regarding the corrosion it is exposed to air, an oxide layer is formed. This layer generally provides protection to further corrosion

Sheffield, University of

325

Mechanical and microstructural behaviour of 2024–7075 aluminium alloy sheets joined by friction stir welding  

Microsoft Academic Search

The aim of the present work is to investigate on the mechanical and microstructural properties of dissimilar 2024 and 7075 aluminium sheets joined by friction stir welding (FSW). The two sheets, aligned with perpendicular rolling directions, have been successfully welded; successively, the welded sheets have been tested under tension at room temperature in order to analyse the mechanical response with

P. Cavaliere; R. Nobile; F. W. Panella; A. Squillace

2006-01-01

326

Correlation between microstructure and microhardness in a friction stir welded 2024 aluminium alloy  

Microsoft Academic Search

A 2024-T351 aluminium alloy has been friction stir welded and the microstructures investigated. An inner HAZ hardness minimum was a result of an overaged S phase, whereas an outer minimum was believed to be due to precipitate dissolution. An interjacent HAZ maximum was attributable to the presence of very fine S phase precipitates. The nugget zone contained ?4?m grains and

M. J. Jones; P. Heurtier; C. Desrayaud; F. Montheillet; D. Allehaux; J. H. Driver

2005-01-01

327

Variation in fluoride content and leaf injury on plants associated with three aluminium smelters in Norway  

Microsoft Academic Search

Fluoride content and leaf injury were recorded in different plant species and genotypes associated with aluminium smelters in northern, continental and maritime parts of Norway. Generally, all deciduous broad-leaved plants were low in fluorides in the spring. The leaf F content increased during the growing season. The F accumulation rate (K) varied with species and exposure conditions. It was highest

Eva Vike; Atle Håbjørg

1995-01-01

328

Aluminium content of drinking waters, fruit juices and soft drinks: contribution to dietary intake.  

PubMed

Concentrations of aluminium in drinking waters (tap water, still mineral water and sparkling mineral water), fruit juices and soft drinks were determined using graphite furnace atomic absorption spectrometry (GFAAS) of samples processed with a HNO3-V205 acid digestion pre-treatment. In water samples, aluminium was determined directly. We verified the sensitivity, accuracy and precision of the method and ruled out matrix interferences. In analysed samples, aluminium values ranged from 4.2 to 165.3 microg/l in drinking water (n=41), from 49.3 to 1,144.6 microg/l in fruit juices (n=47), and from 44.6 to 1053.3 microg/l in soft drinks (n=88). According to the type of container (glass or can) statistically significant differences (P<0.01) have been demonstrated. Considering the mean daily individual consumption of these beverages in Spain, the daily dietary intake of Al supplied by this source is estimated as 156 microg/person/day. This study contributes new data on the Al content of a variety of foods and beverages in Spain and to estimate reliably the total dietary intake of aluminium. PMID:12146520

López, Francisco F; Cabrera, Carmen; Lorenzo, M Luisa; López, M Carmen

2002-06-26

329

Effect of friction on barrelling in square billets of aluminium during cold upset forging  

Microsoft Academic Search

This work deals with the generation of data on cold upset forging of square billets of annealed aluminium under different frictional conditions. Three different aspect ratios and constant load levels were considered for the above said upsetting experiment. The calculations were made on the assumption that the curvature of the barrel followed the geometry of circular arc. The measured radius

K. Manisekar; R. Narayanasamy; S. Malayappan

2006-01-01

330

Predicting the thermal conductivity of aluminium alloys in the cryogenic to room temperature range  

NASA Astrophysics Data System (ADS)

Aluminium alloys are being used increasingly in cryogenic systems. However, cryogenic thermal conductivity measurements have been made on only a few of the many types in general use. This paper describes a method of predicting the thermal conductivity of any aluminium alloy between the superconducting transition temperature (approximately 1 K) and room temperature, based on a measurement of the thermal conductivity or electrical resistivity at a single temperature. Where predictions are based on low temperature measurements (approximately 4 K and below), the accuracy is generally better than 10%. Useful predictions can also be made from room temperature measurements for most alloys, but with reduced accuracy. This method permits aluminium alloys to be used in situations where the thermal conductivity is important without having to make (or find) direct measurements over the entire temperature range of interest. There is therefore greater scope to choose alloys based on mechanical properties and availability, rather than on whether cryogenic thermal conductivity measurements have been made. Recommended thermal conductivity values are presented for aluminium 6082 (based on a new measurement), and for 1000 series, and types 2014, 2024, 2219, 3003, 5052, 5083, 5086, 5154, 6061, 6063, 6082, 7039 and 7075 (based on low temperature measurements in the literature).

Woodcraft, Adam L.

2005-06-01

331

The metal\\/polymer interface in aluminium adhesive joints: A microanalytical study  

Microsoft Academic Search

Aluminium adhesive joints have been prepared with metal pretreatments used in the aerospace industry, namely chromic sulphuric acid pickling (CSA, FPL-etch), phosphoric acid anodizing (PAA), and chromic acid anodizing (CAA). Chemical and physical techniques are discussed which render the interfaces accessible to electron microscopy and microanalysis. These comprise fracturing, selective removal of metal or metal plus oxide through chemical etching,

Felix Nitschke

1990-01-01

332

Enhancement of thermoelectric figure-of-merit by resonant states of aluminium doping in lead selenide  

E-print Network

By adding aluminium (Al) into lead selenide (PbSe), we successfully prepared n-type PbSe thermoelectric materials with a figure-of-merit (ZT) of 1.3 at 850 K. Such a high ZT is achieved by a combination of high Seebeck ...

Zhang, Qinyong

333

SHALLOW WATER MODEL FOR ALUMINIUM ELECTROLYSIS CELLS WITH VARIABLE TOP AND BOTTOM  

Microsoft Academic Search

The MHD wave instability in commercial cells for electrolytic aluminium production is often described using 'shallow water' models. The model (1) is extended for a variable height cathode bottom and anode top to account for realistic cell features. The variable depth of the two fluid layers affects the horizontal current density, the wave development and the stability threshold. Instructive examples

Valdis Bojarevics; Koulis Pericleous

2008-01-01

334

Wear behaviour of cemented carbide tools in dry machining of aluminium alloy  

Microsoft Academic Search

Several causes of tool wear have been investigated in dry machining of aluminium alloy with cemented carbide insert; some of the most important are: adhesion and diffusion. The formation of built-up edge (BUE) and adhesive layer on the tool rake face degrades on the one hand, the shape and efficiency of cutting tool and on the other hand, the surface

G. List; M. Nouari; D. Géhin; S. Gomez; J. P. Manaud; Y. Le Petitcorps; F. Girot

2005-01-01

335

Molecular dynamics simulation of aluminium di#usion in decagonal quasicrystals  

E-print Network

Molecular dynamics simulation of aluminium di#usion in decagonal quasicrystals Stephen Hocker­ tigated by molecular dynamics simulations. Results obtained with newly developed EAM potentials with molecular statics simulations. The qualitative behaviour of the dynamics is also confirmed by ab

Gähler, Franz

336

On interstitial dislocation loops in aluminium bombarded with alpha-particles  

Microsoft Academic Search

Electron transmission microscopy and selected area diffraction have shown that the dislocation loops in aluminium bombarded with 38 Mev alpha-particles lie generally upon the {110} planes with a [110] Burgers vector normal to the loop. These loops are only seen where the alpha-particles come to rest. The theory of diffraction contrast at dislocations (Hirsch et al. 1960) has been used

D. J. Mazey; R. S. Barnes; A. Howie

1962-01-01

337

The structure and formation of dislocation networks in aluminium-magnesium alloys  

Microsoft Academic Search

When investigating rapidly solidified aluminium—magnesium alloys by means of the thin foil technique, dislocation networks were abundantly revealed. It is shown that these are knitted on dislocation forests generated on contact boundaries of sub-dendrites or cells growing from the melt. Knitting occurs mainly by climb when ‘detached’ dislocations nucleating inside the cells during solidification and cooling are trapped by forests.

V. K. Lindroos; H. M. Miekk-Oja

1967-01-01

338

Preparation of aluminium–magnesium alloys and some valuable salts from used beverage cans  

Microsoft Academic Search

The purpose of this work is to recover standard aluminium–magnesium alloy(s) and some valuable salts from used beverage cans (UBCs). The suggested method updated the current recycling technology by augmenting removal of the coating paint, decreasing magnesium loss during melting process and improving hydrochloric acid leaching of the formed slag. Iron impurity present in the leaching solution, was removed by

Mahmoud A Rabah

2003-01-01

339

Formation of Al3Ti during physical vapor deposition of titanium on aluminium  

Microsoft Academic Search

Summary form only given. In the classical approach of W plugs, a Ti \\/ TiN barrier is usually deposited prior to via filling, in order to obtain low contact resistances and satisfactory adherence. Therefore titanium is deposited onto the underlayer aluminium line at the bottom of vias, enabling the formation of Al3Ti at the Ti \\/Al interface. In this study,

L. Ulmer; F. Pitard; D. Poncet

1997-01-01

340

High strain rate superplasticity of AlN particulate reinforced aluminium alloy composites  

Microsoft Academic Search

Ceramic whisker or particulate reinforced aluminium alloy composites have a great potential for automobile engineering components, aerospace structures, semi-conductor packaging and so on, because of the composites ability to exhibit a high specific elastic modulus and specific tensile strength, excellent wear resistance and heat resistance, low thermal expansion and good dimensional stability. A serious problem involving practical application of ceramic

T. Imai; G. LEsperance; B. D. Hong

1994-01-01

341

Biological activities of phthalocyanines. XIV. Effect of hydrophobic phthalimidomethyl groups on the in vivo phototoxicity and mechanism of photodynamic action of sulphonated aluminium phthalocyanines.  

PubMed Central

Aluminium phthalocyanines substituted to different degrees with hydrophilic sulphonic acid and hydrophobic phthalimidomethyl groups were investigated in vivo as new agents for the photodynamic therapy of malignant tumours. Parameters studied included the photodynamic action on EMT-6 mammary tumours in BALB/c mice, the therapeutic window and the potential for direct cell killing, assayed via an in vivo/in vitro test. Although the efficiency of photoinactivation of the EMT-6 tumour increases by a factor of ten with reduction of the number of sulphonic acid groups from four to two, no further effect was seen with the addition of the hydrophobic phthalimidomethyl groups. Addition of the latter groups however increased the potential for direct cell killing by a factor of two and expanded the therapeutic window by a factor of four, thus improving the usefulness of the dye as a photosensitiser for the photodynamic therapy of cancer. PMID:1616852

Boyle, R. W.; Paquette, B.; van Lier, J. E.

1992-01-01

342

Additional information: Anthropology  

E-print Network

Additional information: Anthropology: Dr. De Ann Pendry dpendry@utk.edu 865.974.4408 Department of Anthropology 250 South Stadium Hall Spanish: Dr. Ã?scar Rivera-Rodas oriverar@utk.edu 865.974.7005 Department academic tracks: Latin American Anthropology (taught in English), and Language and Latin American

Tennessee, University of

343

Additive Versus Subtractive Manufacturing  

NSDL National Science Digital Library

For manufacturing students learning the basics, this page from SnoCAMP would be a useful addition to in-class instruction. The webpage combines photographs of examples with descriptive text. This would be a good introduction for students learning the basics about manufacturing.

2013-07-23

344

More Than Additional Space...  

ERIC Educational Resources Information Center

A much needed addition to the Jamestown Elementary School turned out to be more than an expansion of walls for more space. A new educational program, a limited budget, and a short time line were tackled on a team approach basis and were successfully resolved. (Author)

CEFP Journal, 1973

1973-01-01

345

Additional Sources of Information  

Cancer.gov

Additional Sources of Information Developing Medical Imaging Drug and Biological Products Part 1: Conducting Safety Assessments [PDF] (Issued 6/17/2004, Posted 6/17/2004) Part 2: Clinical Indications [PDF] (Issued 6/17/2004, Posted 6/17/2004) Content

346

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

347

Fluency with Basic Addition  

ERIC Educational Resources Information Center

Traditionally, learning basic facts has focused on rote memorization of isolated facts, typically through the use of flash cards, repeated drilling, and timed testing. However, as many experienced teachers have seen, "drill alone does not develop mastery of single-digit combinations." In contrast, a fluency approach to learning basic addition

Garza-Kling, Gina

2011-01-01

348

A novel route of synthesis of aluminium nano-aggregates: an ion beam modification in metal-organic complex  

NASA Astrophysics Data System (ADS)

A novel route for the formation of nano-aggregates of aluminium by ion irradiation of a spin-cast metal-organic thin film of aluminium acetyl acetonate [((CH3CO)2CH)3Al] is reported. Glancing angle x-ray diffraction studies on an irradiated sample show the formation of fcc aluminium clusters. Microstructural studies using transmission electron microscopy show the formation of aggregated branched nanoclusters of diameter ?5-60 nm, which on increasing fluences interconnect through branches and form a network-like structure. Networked structures of aggregated Al clusters might have formed due to overlapping of multiple ion tracks at relatively higher fluences.

Dhara, S.; Panigrahi, B. K.; Nair, K. G. M.; Magudapathy, P.; Saibaba, Saroja; Reddy, G. L. N.

2001-01-01

349

Vinyl capped addition polyimides  

NASA Technical Reports Server (NTRS)

Polyimide resins (PMR) are generally useful where high strength and temperature capabilities are required (at temperatures up to about 700 F). Polyimide resins are particularly useful in applications such as jet engine compressor components, for example, blades, vanes, air seals, air splitters, and engine casing parts. Aromatic vinyl capped addition polyimides are obtained by reacting a diamine, an ester of tetracarboxylic acid, and an aromatic vinyl compound. Low void materials with improved oxidative stability when exposed to 700 F air may be fabricated as fiber reinforced high molecular weight capped polyimide composites. The aromatic vinyl capped polyimides are provided with a more aromatic nature and are more thermally stable than highly aliphatic, norbornenyl-type end-capped polyimides employed in PMR resins. The substitution of aromatic vinyl end-caps for norbornenyl end-caps in addition polyimides results in polymers with improved oxidative stability.

Vannucci, Raymond D. (inventor); Malarik, Diane C. (inventor); Delvigs, Peter (inventor)

1991-01-01

350

Addition deletion networks  

NASA Astrophysics Data System (ADS)

We study structural properties of growing networks where both addition and deletion of nodes are possible. Our model network evolves via two independent processes. With rate r, a node is added to the system and this node links to a randomly selected existing node. With rate 1, a randomly selected node is deleted and its parent node inherits the links of its immediate descendants. We show that the in-component size distribution decays algebraically, ck ~ k-? as k ? ?. The exponent ? = 2 + (r - 1)-1 varies continuously with the addition rate r. Structural properties of the network including the height distribution, the diameter of the network, the average distance between two nodes and the fraction of dangling nodes are also obtained analytically. Interestingly, the deletion process leads to a giant hub, a single node with a macroscopic degree whereas all other nodes have a microscopic degree.

Ben-Naim, E.; Krapivsky, P. L.

2007-07-01

351

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

352

Gasoline detergent additive  

Microsoft Academic Search

This patent describes a gasoline fuel composition. It comprises a major portion of a gasoline fuel and a minor amount, as a gasoline detergent additive, of a Mannich coupled product of bis-polyisobutylene succinimide of an amine, prepared by: reacting an alkenyl succinimide acid anhydride with an amine to form a bis-succinimide; treating the bis-succinimide with nonylphenol in the presence of

S. Herbstman; T. E. Hayden; T. E. Nalesnik; N. Benfaremo

1991-01-01

353

Diesel fuel detergent additive  

Microsoft Academic Search

This patent describes a diesel fuel composition. It comprises a major portion of a diesel fuel, and a minor amount, as a diesel fuel injector detergent additive, of a Mannich coupled product of bis-polyisobutylene succinimide of an amine, prepared by: reacting an alkenyl succinimide acid anhydride with an amine to form a bis-succinimide; treating the bis-succinimide with nonylphenol in the

S. Herbstman; K. S. Verk; T. E. Nalesnik; N. Benfaremo

1991-01-01

354

Addition and Subtraction  

NSDL National Science Digital Library

With the following information you will be able to add and subtract . You will master adding and subtracting up to 12. Adding and subtracting can be done! At this site you will be able to go on a space mission, the mission is... answer all of the horizontal addition and subtraction problems. If you get the problem right, then the mission is passed. If no mission is failed. Just ...

Ms.Richards

2006-10-10

355

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

356

Functional Generalized Additive Models.  

PubMed

We introduce the functional generalized additive model (FGAM), a novel regression model for association studies between a scalar response and a functional predictor. We model the link-transformed mean response as the integral with respect to t of F{X(t), t} where F(·,·) is an unknown regression function and X(t) is a functional covariate. Rather than having an additive model in a finite number of principal components as in Müller and Yao (2008), our model incorporates the functional predictor directly and thus our model can be viewed as the natural functional extension of generalized additive models. We estimate F(·,·) using tensor-product B-splines with roughness penalties. A pointwise quantile transformation of the functional predictor is also considered to ensure each tensor-product B-spline has observed data on its support. The methods are evaluated using simulated data and their predictive performance is compared with other competing scalar-on-function regression alternatives. We illustrate the usefulness of our approach through an application to brain tractography, where X(t) is a signal from diffusion tensor imaging at position, t, along a tract in the brain. In one example, the response is disease-status (case or control) and in a second example, it is the score on a cognitive test. R code for performing the simulations and fitting the FGAM can be found in supplemental materials available online. PMID:24729671

McLean, Mathew W; Hooker, Giles; Staicu, Ana-Maria; Scheipl, Fabian; Ruppert, David

2014-01-01

357

Appendix: Additional Contributions  

NASA Astrophysics Data System (ADS)

The number of contributions to the Symposium was so high that only the review and invited talks have found place, in the form of articles, in this volume. This Appendix lists all these additional contributions (oral and posters) which are not present as articles. The abstracts of all contributions were published in a booklet produced by the Local Organizing Committee and are available at the SAO/NASA Astrophysics Data System (ADS). More information on these contributions (PowerPoint presentations and/or articles) have been made public in the Internet web site of the conference (http://cab.inta-csic.es/molecular_universe/).

2011-12-01

358

Siloxane containing addition polyimides  

NASA Technical Reports Server (NTRS)

Addition polyimide oligomers have been synthesized from bis(gamma-aminopropyl) tetramethyldisiloxane and 3, 3', 4, 4'-benzophenonetetracarboxylic dianhydride using a variety of latent crosslinking groups as endcappers. The prepolymers were isolated and characterized for solubility (in amide, chlorinated and ether solvents), melt flow and cure properties. The most promising systems, maleimide and acetylene terminated prepolymers, were selected for detailed study. Graphite cloth reinforced composites were prepared and properties compared with those of graphite/Kerimid 601, a commercially available bismaleimide. Mixtures of the maleimide terminated system with Kerimid 601, in varying proportions, were also studied.

Maudgal, S.; St. Clair, T. L.

1984-01-01

359

Oil additive process  

SciTech Connect

This patent describes a method of making an additive comprising: (a) adding 2 parts by volume of 3% sodium hypochlorite to 45 parts by volume of diesel oil fuel to form a sulphur free fuel, (b) removing all water and foreign matter formed by the sodium hypochlorite, (c) blending 30 parts by volume of 24% lead naphthanate with 15 parts by volume of the sulphur free fuel, 15 parts by volume of light-weight material oil to form a blended mixture, and (d) heating the blended mixture slowly and uniformly to 152F.

Bishop, H.

1988-10-18

360

Dry wear behaviour and its relation to microstructure of novel 6092 aluminium alloy–Ni 3Al powder metallurgy composite  

Microsoft Academic Search

Novel aluminium alloy matrix composites reinforced by 15vol.% Ni3Al intermetallic particles were prepared by a powder metallurgy route. The 6092 aluminium alloy was produced by gas atomisation, followed by blending with Ni3Al particles. Consolidation by extrusion at 515°C, with an extrusion ratio of 30:1, produced a uniform distribution of Ni3Al in the Al alloy matrix. The wear properties of the

Y. Wang; W. M. Rainforth; H. Jones; M. Lieblich

2001-01-01

361

Observations of Schottky and Poole-Frenkel emission in lead phthalocyanine thin films using aluminium injecting electrodes  

Microsoft Academic Search

DC current density-voltage measurements have been performed on vacuum evaporated aluminium-lead phthalocyanine-gold sandwich structures for both electrical polarities. The electrical characteristics differed markedly depending on whether the positive hole-injecting electrode was gold (forward-bias) or aluminium (reverse-bias). An extensive study of such characteristics revealed two distinct regions in the forward-bias characteristics. In the first of these a power-law dependence of current

T. S. SHAFAI; R. D. GOULD

1992-01-01

362

Electron metallography of the aluminium-water vapour reaction and its relevance to stress-corrosion susceptibility  

Microsoft Academic Search

The reaction of filmed surfaces of aluminium and certain aluminium alloys with water vapour saturated air at 70 C has been\\u000a morphologically studied at high resolution using a JEOL 100C Temscan. Electron-transparent specimens, reacted for up to 24\\u000a h, have been examined using a combination of SE (secondary electron) and STE (scanning transmission electron) imaging modes\\u000a to examine both the

G. M. Scamans; A. S. Rehal

1979-01-01

363

Galvanostatic electrodeposition of aluminium nano-rods for Li-ion three-dimensional micro-battery current collectors  

Microsoft Academic Search

Constant current and pulsed current electrodeposition of aluminium nano-rods, for use as three-dimensional (3D) Li-ion micro-battery current collectors, have been studied using an ionic liquid electrolyte (1-ethyl-3-methylimidazolium chloride\\/aluminium chloride) and a template consisting of a commercial alumina membrane. It is shown that the homogeneity of the height of the rods can be improved significantly by inclusion of a short (i.e.

Gabriel Oltean; Leif Nyholm; Kristina Edström

2011-01-01

364

A phenomenon of triboelectrization in aluminium oxide–polytetrafluoroethylene sliding contact joint operating under reduced lubrication conditions  

Microsoft Academic Search

A sliding contact joint: aluminium oxide–PTFE operating with lubricant is a dielectric–dielectric liquid–dielectric type joint. Taking into account the tribological properties of aluminium oxide and PTFE and the fact, that these materials occupy extreme positions in the triboelectrization series, it could be stated that in this group of sliding joints we deal with an extreme joint. The contact electrification and

Henryk Wistuba

1997-01-01

365

A Parametric Study of the Low-Impulse Blast Behaviour of Fibre-Metal Laminates Based on Different Aluminium Alloys  

Microsoft Academic Search

A parametric study has been undertaken in order to investigate the influence of the properties of the aluminium alloy on the blast response of fibre-metal laminates (FMLs). The finite element (FE) models have been developed and validated using experi-mental data from tests on FMLs based on a 2024-O aluminium alloy and a woven glass-fibre\\/polypropylene composite (GFPP). A vectorized user material

Thuc Vo; Zhongwei Guan; Wesley Cantwell; Graham Schleyer

2012-01-01

366

Is potroom asthma due more to sulphur dioxide than fluoride? An inception cohort study in the Australian aluminium industry  

Microsoft Academic Search

ObjectivesAlthough an asthma-like syndrome has been recognised in aluminium smelter workers for over 70 years, the causal agent has been difficult to identify.MethodsAn inception cohort study was conducted at two Australian aluminium smelters where 446 employees participated over a period of 9 years. Cumulative exposures between interviews were estimated from job histories using a task exposure matrix based on measurements

Michael John Abramson; Geza Paul Benke; Jisheng Cui; Nicholas Hubert de Klerk; Anthony Del Monaco; Martine Dennekamp; Lin Fritschi; Arthur William Musk; Malcolm Ross Sim

2010-01-01

367

Performance Boosting Additive  

NASA Technical Reports Server (NTRS)

Mainstream Engineering Corporation was awarded Phase I and Phase II contracts from Goddard Space Flight Center's Small Business Innovation Research (SBIR) program in early 1990. With support from the SBIR program, Mainstream Engineering Corporation has developed a unique low cost additive, QwikBoost (TM), that increases the performance of air conditioners, heat pumps, refrigerators, and freezers. Because of the energy and environmental benefits of QwikBoost, Mainstream received the Tibbetts Award at a White House Ceremony on October 16, 1997. QwikBoost was introduced at the 1998 International Air Conditioning, Heating, and Refrigeration Exposition. QwikBoost is packaged in a handy 3-ounce can (pressurized with R-134a) and will be available for automotive air conditioning systems in summer 1998.

1999-01-01

368

RGB Additive Color  

NSDL National Science Digital Library

Color is all around us. RGB is the color system that is used when mixing light. The RGB system is what we use in computers, televisions, stage lighting, displays and more. It is also called the additive color system because the colors are combined or added to each other to make the colors that we see. What wavelength goes with a color? Remember that a a nanometer is a unit of length in the metric system equal to one billionth of a meter. NASA What is a wave? NASA Color Why is the sky blue? What is RGB and how and where is it used? RGB World 21st Century Color Theory RGB colors are identified on computers by a color value that ranges for R, G, and B, ...

Engelman, Mr.

2010-12-05

369

Water-soluble aluminium phthalocyanine–polymer conjugates for PDT: photodynamic activities and pharmacokinetics in tumour-bearing mice  

PubMed Central

The potential use of unsubstituted aluminium phthalocyanine (AlClPc) as a sensitizer for photodynamic therapy (PDT) of cancer has not been fully exploited in spite of its higher efficiency as compared to the sulphonated derivatives. This is largely due to the strong hydrophobic character of AlClPc which renders the material difficult to formulate for in vivo administration. We prepared two water-soluble derivatives of AlClPc by axial coordination of polyethyleneglycol (PEG, MW 2000) or polyvinylalcohol (PVA, MW 13 000–23 000) to the central aluminium ion. Their photodynamic activities were evaluated in vitro against the EMT-6 mouse mammary tumour cells and in vivo against the EMT-6 and the colon carcinoma Colo-26 tumours implanted intradermally in Balb/c mice. Pharmacokinetics were studied in the EMT-6 tumour-bearing mice. After 1 h incubation, the light dose required to kill 90% of cells (LD90) was at least three times less for AlClPc (Cremophor emulsion) as compared to AlPc–PEG and AlPc–PVA, while after 24 h incubation all three preparations were highly phototoxic. All three dye preparations induced complete EMT-6 tumour regression in 75–100% of animals at a low drug dose (0.25 ?mol kg?1) following PDT (400 J cm?2, 650–700 nm) at 24 h pi. Complete tumour regression in the Colo-26 tumour model was obtained in 30% of mice at a dose of 2 ?mol kg?1. In the non-cured animals, AlPc–PVA induced the most significant tumour growth delay. This dye showed a prolonged plasma half-life (6.8 h) as compared to AlClPc (2.6 h) and AlPc–PEG (23 min), lower retention by liver and spleen and higher tumour-to-skin and tumour-to-muscle ratios. Our data demonstrate that addition of hydrophilic axial ligands to AlPc, while modifying in vitro and in vivo kinetics, does not reduce the PDT efficiency of the parent molecule. Moreover, in the case of the polyvinylalcohol derivative, axial coordination confers advantageous pharmacokinetics to AlPc, which makes this photosensitizer a valuable, water soluble candidate drug for clinical PDT of cancer. © 1999 Cancer Research Campaign PMID:10408394

Brasseur, N; Ouellet, R; Madeleine, C La; Lier, J E van

1999-01-01

370

A comparative ecotoxicity analysis of ?- and ?-phase aluminium oxide nanoparticles towards a freshwater bacterial isolate Bacillus licheniformis.  

PubMed

Crystalline structure of nanoparticles may influence their physicochemical behaviour as well as their toxicological impact on biota. The differences in orientation of the atoms result in the variations in chemical stability. Thus, toxicological impacts of different crystalline phases of aluminium oxide nanoparticles are expected to vary. The present study brings out a comparative toxicity analysis of ?-phase and ?-phase aluminium oxide nanoparticles of comparable hydrodynamic size range towards a freshwater bacterial isolate Bacillus licheniformis at low exposure concentrations (5, 1, 0.5 and 0.05 µg/mL). Upon 2-h exposure, the ?-aluminium oxide particles showed lower toxicity than the ?-phase aluminium oxide. The lower level of oxidative stress generation and cell membrane damage in case of the ?-phase aluminium oxide nanoparticles substantiated the toxicity results. The involvement of protein, lipopolysaccharides in nanoparticle-cell surface interaction, was noted in both the cases. To conclude, the crystallinity of aluminium oxide nanoparticles played an important role in the interaction and the toxicity response. PMID:24861316

Pakrashi, Sunandan; Kumar, Deepak; Iswarya, V; Bhuvaneshwari, M; Chandrasekaran, N; Mukherjee, Amitava

2014-12-01

371

Addition and Subtraction... Why Not?  

NSDL National Science Digital Library

Practice doing Addition and Subtraction! Addition: Here you can use virtual blocks to make addition problems. Addition with Base-10 Blocks Now you rock at doing addition with blocks. Try doing some Subtraction! Subtraction: Try solving subtraction problems using the blocks. Subtraction with Base-10 Blocks Just for fun: Check out this site and just try some fun stuff... Addition and Subtraction Mania ...

Mr. Baggaley

2008-11-17

372

Surface modification of aluminium alloys using hybrid treatment techniques  

NASA Astrophysics Data System (ADS)

The application of electron and laser beams to the modification of metal and alloys opens up new possibilities of improving the materials properties. In recent years, the studies aimed at developing new materials have brought about the development of hybrid treatment techniques. These techniques perform an additional alloying in the zone treated, which has a substantial effect on the physical and mechanical properties of the materials processed. In this work we report results on the microstructural changes and mechanical properties of heat-treated AlSi12CuNiMg alloys resulting from additional alloying with Fe, Co, Ni, Cr by hybrid electron-beam techniques. It is established that the mechanical properties of Al-Si alloys can be improved by means of additional alloying with Fe, Co, Ni, Cr by hybrid electron-beam techniques. The specimens' properties practically do not change after heat-treatment (aging) for up to 200 hours at 250 °C.

Petrov, P.

2012-03-01

373

Laser Surface Pre-treatment of Aluminium for Hybrid Joints with Glass Fibre Reinforced Thermoplastics  

NASA Astrophysics Data System (ADS)

Lightweight construction is a major trend in the automotive industry. Theconnection of fibre reinforced plastics with aluminium is consequently seen as promising prospect. In this regard, thermal joining can be applied for bonding of such hybrid joints. But in order to create a load bearing metal plastic joint, the surface of the metal has to be pre-treated. Recent research has shown that with laser surface pre-treatment high joint strengths are obtained. Yet there are a variety of laser sources and manufacturable surface topographies with structure sizes ranging from macroscopic to nanoscopic profiles. Within this work,macroscopic, microscopic and nanoscopic laser processed structures are created on aluminium and consequently joined to glass fibre reinforced thermoplastics of different fibre length and fibre content. High shear tensile strengths of up to 42 N/mm2 were obtained depending on the allocated material and the surface pre-treatment.

Heckert, André; Zaeh, Michael F.

374

Wettability behaviour of RTV silicone rubber coated on nanostructured aluminium surface  

NASA Astrophysics Data System (ADS)

A nanostructutered superhydrophobic surface was elaborated by applying an RTV silicone rubber coating on electrochemically processed aluminium substrates. Study of anodisation voltage on surface morphology showed that higher anodising voltage led to larger pore sizes. Scanning electron microscopy image analysis showed bird's nest and beehive structures formed on anodised surfaces at 50 V and 80 V. Water static contact angle on the treated surfaces reached up to 160° at room temperature. Study of superhydrophobic surfaces at super cooled temperature showed important delayed freezing time for RTV hydrophobic surfaces when compared to non-treated aluminium. However, lower wettability was observed when surface temperature went down from 20 °C to -10 °C. Also, it was found that the capacitance of superhydrophobic surfaces decreased with increasing anodising voltage.

Momen, Gelareh; Farzaneh, Masoud; Jafari, Reza

2011-05-01

375

Fabrication of self-healing super-hydrophobic surfaces on aluminium alloy substrates  

NASA Astrophysics Data System (ADS)

We present a method to fabricate a super-hydrophobic surface with a self-healing ability on an aluminium alloy substrate. The coatings are obtained by combining a two-step process (first, the substrate is immersed in a solution of HCl, HF and H2O, and then in boiling water) and succeeding surface fluorination with a solution of poly(vinylidene-fluoride-co-hexafluoropropylene) and a fluoroalkyl silane. The morphological features and chemical composition were studied by scanning electron micrometry and energy-dispersive X-ray spectroscopy. The prepared super-hydrophobic aluminium surfaces showed hierarchical structures forming pores, petals and particles with a contact angle of 161° and a sliding angle of 3°.

Wang, Yang; Wei Liu, Xiao; Zhang, Hai Feng; Zhou, Zhi Ping

2015-04-01

376

Low-Temperature Synthesis of Aluminium Nitride Film by HCD-Type Ion Plating  

NASA Astrophysics Data System (ADS)

Aluminium nitride (AlN) thin films were deposited on glass substrates, using aluminium and nitrogen as source materials, by hollow cathode discharge (HCD)-type ion plating. The films were evaluated using X-ray diffraction, scanning electron microscopy, infrared transmission spectroscopy and Auger electron spectroscopy, and their densities were measured. The phase of the deposits changed from Al to Al+AlN and to AlN with an increase in nitrogen flow rate. The structure of the AlN films varied from a dense structure to columnar structure with a rise in nitrogen flow rate. The film with the dense structure had a density near the theoretical value. Oxygen caused by the attack of H2O in air was detected only on the surface of films with the dense structure, but throughout the inside of the films with the columnar structure.

Kishi, Matsuo; Suzuki, Mizuaki; Ogawa, Kenichi

1992-04-01

377

Aluminium and hydrogen ions inhibit a mechanosensory calcium-selective cation channel  

NASA Technical Reports Server (NTRS)

The tension-dependent activity of mechanosensory calcium-selective cation channels in excised plasmalemmal patches from onion bulb scale epidermis is modulated by pH in the physiologically meaningful range between 4.5 and 7.2. It is rapidly lowered by lowering pH and rapidly raised by raising pH. Channel activity is effectively inhibited by low levels of aluminium ions and activity can be partially restored by washing for a few minutes. We suggest that under normal conditions the sensitivity of the mechanosensory channels to pH of the wall free space plays important roles in regulation of plant activities such as growth. We further suggest that, when levels of acid and aluminium ions in the soil solution are high, they might inhibit similar sensory channels in cells of the root tip, thus contributing critically to the acid soil syndrome.

Ding, J. P.; Pickard, B. G.

1993-01-01

378

Synthesis of ettringite: a way to deal with the acid wastewaters of aluminium anodising industry.  

PubMed

Synthesis of ettringite from acid wastewaters of the aluminium anodising industry has been studied as a possible route of reducing the emissions to the environment, recovering at the same time resource materials as a useful marketable mineral. Wastewaters of different concentrations have been subjected to the process of synthesis suspending calcium oxide and calcium aluminate powders at different time and pH conditions. High caustic alkalinity (pH approximately 12) and low sulphate concentrations (<0.1 M) are the most suitable conditions to synthesise ettringite. The mineral characterisation has been performed using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and differential thermal analysis (DTA), proving the high purity of the pursued solid product when hydrated in the appropriate sodium hydroxide concentrations. In such conditions, around 90% of the aluminium initially present in the wastewater solutions is recovered in the form of ettringite. PMID:15607165

Alvarez-Ayuso, E; Nugteren, H W

2005-01-01

379

Development of Aluminium Vacuum Chambers for the LHC Experiments at CERN  

E-print Network

Beam losses may cause activation of vacuum chamber walls, in particular those of the Large Hadron Collider (LHC) experiments. For the High Luminosity (HL-LHC), the activation of such vacuum chambers will increase. It is therefore necessary to use a vacuum chamber material which interacts less with the circulating beam. While beryllium is reserved for the collision point, a good compromise between cost, availability and transparency is obtained with aluminium alloys; such materials are a preferred choice with respect to austenitic stainless steel. Manufacturing a thin-wall aluminium vacuum chamber presents several challenges as the material grade needs to be machinable, weldable, leak-tight for small thicknesses, and able to withstand heating to 250°C for extended periods of time. This paper presents some of the technical challenges during the manufacture of these vacuum chambers and the methods for overcoming production difficulties, including surface treatments and Non-Evaporable Getter (NEG) thin-film coat...

Gallilee, M; Costa-Pinto, P; Lepeule, P; Perez-Espinos, J; Marques Antunes Ferreira, L; Prever-Loiri, L; Sapountzis, A

2014-01-01

380

Phosphate sensor based on immobilized aluminium-morin in poly (glycidyl methacrylate) microspheres  

NASA Astrophysics Data System (ADS)

This paper reports the development of dihydrogen phosphate ion (H2PO4-) sensor in free solution and immobilized aluminium-morin (Al-Mo) complex on poly(glycidyl methacrylate) (pGMA) microspheres. The immobilization was carried out by suspension photopolymerization technique. Based on Al-Mo solution work, phosphate can be detected from 0.1 - 15.0 ppm of dihydrogen phosphate at pH 5. Phosphate detection only takes about 5 minutes. Morphology analyses showed that the immobilization of Aluminium-Morin complex maintained the size of the microspheres and proved that entrapment involves in the formation of the microspheres. This result is further explained by Attenuated Total Reflectance (ATR) spectrum which does not show any formation of new bands. The microspheres were then used for further applications.

Ahmad, Amalina; Hanifah, Sharina Abu; Hasbullah, Siti Aishah; Suhud, Khairi; Zaini, Norhadisah Mohd; Heng, Lee Yook

2014-09-01

381

Fabrication of porous aluminium with directional pores through thermal decomposition method  

NASA Astrophysics Data System (ADS)

Lotus-type porous metals were fabricated by unidirectional solidification in pressurized gas atmosphere. The elongated pres are evolved by insoluble gas resulted from the solubility gap between liquid and solid when the melt is solidified. Recently we developed a novel fabrication technique, in which gas compounds are used as a source of dissolving gas instead of the high pressure. In the present work this gas compound method was applied to fabrication of lotus aluminium. Hydrogen decomposed from calcium hydroxide, sodium bicarbonate and titanium hydride evolves cylindrical pores in aluminium. The porosity is about 20%. The pore size decreases and the pore number density increases with increasing amount of calcium hydroxide, which is explained by increase in pore nucleation sites.

Nakajima, H.; Y Kim, S.; Park, J. S.

2009-05-01

382

One-step aluminium-assisted crystallization of Ge epitaxy on Si by magnetron sputtering  

SciTech Connect

In this work, one-step aluminium-assisted crystallization of Ge on Si is achieved via magnetron sputtering by applying an in-situ low temperature (50?°C to 150?°C) heat treatment in between Al and Ge depositions. The effect of heat treatment on film properties and the growth mechanism of Ge epitaxy on Si are studied via X-ray diffraction, Raman and transmission electron microscopy analyses. Compared with the conventional two-step process, the one-step aluminium-assisted crystallization requires much lower thermal budget and results in pure Ge epitaxial layer, which may be suitable for use as a virtual substrate for the fabrication of III-V solar cells.

Liu, Ziheng, E-mail: ziheng.liu@unsw.edu.au; Hao, Xiaojing; Ho-Baillie, Anita; Green, Martin A. [School of Photovoltaic and Renewable Energy Engineering, University of New South Wales, Sydney 2052 (Australia)

2014-02-03

383

Dosimetric response for crystalline and nanostructured aluminium oxide to a high-current pulse electron beam.  

PubMed

The main thermoluminescent (TL) and dosimetric properties of the detectors based on anion-defective crystalline and nanostructured aluminium oxide after exposure to a high-current pulse electron beam are studied. TL peaks associated with deep-trapping centres are registered. It is shown that the use of deep-trap TL at 200-600°? allows registering absorbed doses up to 750 kGy for single-crystalline detectors and those up to 6 kGy for nanostructured ones. A wide range of the doses registered, high reproducibility of the TL signal and low fading contribute to a possibility of using single-crystalline and nanostructured aluminium oxide for the dosimetry of high-current pulse electron beams. PMID:24990829

Nikiforov, S V; Kortov, V S

2014-11-01

384

Fabrication of Nano-Composite Surface Layers on Aluminium Employing Friction Stir Processing Technique  

SciTech Connect

Al/Al{sub 2}O{sub 3} nano-composite surface layer was fabricated via friction stir processing technique. Commercial AA6082 aluminium alloy extruded bar and nanometric Al{sub 2}O{sub 3} powder were subjected to friction stir processing at a substrate travel speed of 80 mm/min and a tool rotation speed of 1000 rpm using a hardened H-13 tool steel. The grain structure and reinforcement particles were investigated by using optical and scanning electron microscopy. Results show that Al{sub 2}O{sub 3} particles can be more uniformly dispread in aluminium substrate by increasing the number of processing passes. Also, hardness enhancement of the nano-composite surface layer was found. This is attributed to uniform dispersion of Al{sub 2}O{sub 3} particles.

Bozorg, S. F. K.; Zarghani, A. S.; Zarei-Hanzaki, A. [School of Metallurgy and Materials Engineering, Faculty of Engineering, University of Tehran, Tehran, P.O. Box: 14395-553 (Iran, Islamic Republic of)

2010-03-11

385

Microstructure heterogeneity after the ECAP process and its influence on recrystallization in aluminium  

SciTech Connect

The main purpose of the present work is to describe the qualitative and quantitative behaviours of aluminium during high strain plastic deformation and the effect of deformation on the subsequent recrystallization process. An Electron Backscatter Diffraction analysis of aluminium after the Equal channel angular pressing (ECAP) and recrystallization process is presented. In order to do this, several topological maps are measured for samples processed by 4 and 8 passes and recrystallized. The processing was conducted with route C. For all samples, distributions of grain size, misorientation, image quality factor (IQ) and texture were preceded and then analysed in some detail. - Highlights: ? Describe the microstructure fragmentation in aluminum. ? High strain plastic deformation and effect of deformation on recrystallization. ? The microstructure fragmentation and its influence on recrystallization. ? Image quality factor and misorientation characteristics are examined using EBSD.

Wronski, S., E-mail: wronski@fis.agh.edu.pl [Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Kraków (Poland); Tarasiuk, J., E-mail: tarasiuk@ftj.agh.edu.pl [Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Kraków (Poland); Bacroix, B., E-mail: brigitte.bacroix@univ-paris13.fr [LPMTM-CNRS, Université Paris XIII, 99, av. J.B. Clement, 93 430 Villetaneuse (France); Wierzbanowski, K., E-mail: wierzban@ftj.agh.edu.pl [Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Kraków (Poland); Paul, H., E-mail: nmpaul@imim-pan.krakow.pl [Institute of Metallurgy and Materials Science of Polish Academy of Sciences, Reymonta Street 25, 30-059 Kraków (Poland)

2013-04-15

386

Unequivocal identification of intracellular aluminium adjuvant in a monocytic THP-1 cell line  

PubMed Central

Aluminium-based adjuvants (ABA) are the predominant adjuvants used in human vaccinations. While a consensus is yet to be reached on the aetiology of the biological activities of ABA several studies have identified shape, crystallinity and size as critical factors affecting their adjuvanticity. In spite of recent advances, the fate of ABA following their administration remains unclear. Few if any studies have demonstrated the unequivocal presence of intracellular ABA. Herein we demonstrate for the first time the unequivocal identification of ABA within a monocytic T helper 1 (THP-1) cell line, using lumogallion as a fluorescent molecular probe for aluminium. Use of these new methods revealed that particulate ABA was only found in the cell cytoplasm. Transmission electron microscopy revealed that ABA were contained within vesicle-like structures of approximately 0.5–1??m in diameter. PMID:25190321

Mold, Matthew; Eriksson, Håkan; Siesjö, Peter; Darabi, Anna; Shardlow, Emma; Exley, Christopher

2014-01-01

387

Evaluation of constitutive models for textured aluminium alloys using plane-strain tension and shear tests  

Microsoft Academic Search

The constitutive modelling of the strongly textured aluminium alloys AA6063-T6 and AA7003-T6 is studied. The materials were\\u000a delivered in the form of flat extruded profiles. Plane-strain tension and shear tests in the plane of the flat profiles are\\u000a performed. The tests are then used to evaluate a constitutive model including an anisotropic yield function, the associated\\u000a flow rule and a

Dasharatha Achani; Odd-Geir Lademo; Olaf Engler; Odd Sture Hopperstad

2011-01-01

388

Use of hydration inhibitors to improve bond durability of aluminium adhesive joints  

Microsoft Academic Search

The adsorption of selected organic hydration inhibitors onto Forest Products Laboratory (FPL)-etched aluminium surfaces and the subsequent hydration of the treated surfaces have been studied using X-ray photoelectron spectroscopy (XPS) and surface behaviour diagrams (SBDs) supplemented by Fourier Transform Infra-red Spectroscopy (FTIR). Wedge tests were used to evaluate performance of these inhibitors in improving bond durability and the locus of

G. D. Davis; J. S. Ahearn; L. J. Matienzo; J. D. Venables

1985-01-01

389

Surface energy and chemical characteristics of interfaces of adhesively bonded aluminium joints  

Microsoft Academic Search

The deleterious effects of water on the physico-chemical aspects of the durability of adhesively bonded aluminium joints has been investigated. Emphasis was placed on analytical techniques that lead to the better understanding of changes induced at the metal\\/epoxy interface by the presence of water. Analytical techniques such as contact angle measurements, X-ray photoelectron spectroscopy and X-ray diffraction were practical in

G. Kim; F. Ajersch

1994-01-01

390

A sensitive, rapid and inexpensive method to assess aluminium(III) ions in technetium eluates.  

PubMed

The aim of the study was to validate a semiquantitative analytical method to identify the aluminium(III) [Al(III)] concentration in 99Mo/99mTc generator eluates to check the European Pharmacopoeia (Ph. Eur.) requirement (<5 ?g/ml). Three different solutions measuring 20 ml - 0.2% 1,10-phenanthroline, 0.05% chrome azurol S and 20% hexamethylenetetramine - were prepared. A cellulose filter paper was subsequently immersed in them, dried overnight at room temperature and cut into rectangles. A volume of 5 ?l of first eluates of various 99Mo/99mTc generators was placed onto a reagent paper and the spot colour was compared with a standard aluminium solutions scale (0-100 ?g/ml). A cyan/magenta/yellow/key (CMYK) model analysis was adapted to quantify the intensity of colour on the paper, and the presence of aluminium in the eluates was detected by a spectrophotometer. Small changes in standard solution pH (4.1-5.2) and chrome azurol S concentration did not affect the analysis. The cyan channel image analysis was proportional to the Al3+ solution concentration (y=25 019x+1489, R2=0.9554 within 2.5-8 ?g/ml). The detection limit for aluminium by the visual test method is about 1 ?g/ml, and fading is absent. The cyan channel image analysis method is independent of the observer and is applicable for the evaluation of the chemical purity of 99Mo/99mTc generator eluates. Our colorimetric 'spot test' is advantageous for the visual evaluation of Al pertechnetate concentrations as required by Ph. Eur. showing a sensitivity and a limit of detection superior to that of commercially available spot systems. PMID:24681768

Buroni, Federica E; Lodola, Lorenzo; Persico, Marco G; Aprile, Carlo

2014-07-01

391

Adult respiratory distress syndrome following aluminium phosphide ingestion. Report of 4 cases.  

PubMed

Four cases of adult respiratory distress syndrome (ARDS) following aluminium phosphide ingestion (ALP) are being reported. The dose of the intoxicant varied from 2 tablets (6.0 gm) to 3 tablets (9.0 gm). All patients had shock at admission and developed ARDS within 6 hours. The exhalation of Phosphine, (PH3) detected by positive silver nitrate paper test, was the possible noxious triggering factor in our cases. The cases are being reported because of their rare occurrence. PMID:2613620

Chugh, S N; Ram, S; Mehta, L K; Arora, B B; Malhotra, K C

1989-04-01

392

Quasi-brittle fracture during structural impact of AA7075-T651 aluminium plates  

Microsoft Academic Search

The stress–strain behaviour of the aluminium alloy 7075 in T651 temper is characterized by tension and compression tests. The material was delivered as rolled plates of thickness 20 mm. Quasi-static tension tests are carried out in three in-plane directions to characterize the plastic anisotropy of the material, while the quasi-static compression tests are done in the through-thickness direction. Dynamic tensile tests

Tore Børvik; Odd Sture Hopperstad; Ketill O. Pedersen

2010-01-01

393

Arsenic removal during conventional aluminium-based drinking-water treatment  

Microsoft Academic Search

The changing forms and concentrations of arsenic through aluminium-based coagulation treatment processes were tracked for three drinking-water treatment plants. This has provided direct evidence of where and how arsenic is removed. In general, soluble As(V) is converted to particulate As(V) by adsorption during rapid mixing, and is removed along with naturally occurring particulate arsenic predominantly by clarification. Soluble As(III) tracks

Jan Gregor

2001-01-01

394

A crystallographic texture perspective formability investigation of aluminium 5052 alloy sheets at various annealing temperatures  

Microsoft Academic Search

Formability, an important mechanical property of the sheet metal is strongly reliant on the crystallographic texture. Consequently deep drawability is also influenced. This paper deals with the perspective of crystallographic texture and its relevance with the formability of AA 5052 aluminium alloy sheet of 2mm thickness annealed at four different temperatures namely 200°C, 250°C, 300°C and 350°C. Forming limit diagrams

R. Narayanasamy; R. Ravindran; K. Manonmani; J. Satheesh

2009-01-01

395

Numerical and experimental study of dry cutting for an aeronautic aluminium alloy (A2024-T351)  

Microsoft Academic Search

In the present contribution, numerical and experimental methodologies concerning orthogonal cutting are proposed in order to study the dry cutting of an aeronautic aluminium alloy (A2024-T351). The global aim concerns the comprehension of physical phenomena accompanying chip formation according to cutting velocity variation.For the numerical model, material behaviour and its failure criterion are based on the Johnson–Cook law. The model

Tarek Mabrouki; François Girardin; Muhammad Asad; Jean-François Rigal

2008-01-01

396

Application of cold spraying for flux-free brazing of aluminium alloy 6060  

Microsoft Academic Search

In the present study, samples of aluminium alloy 6060 were coated by cold spraying with a powder of brazing alloy Al12Si.\\u000a The influence of the process gas temperature on particle velocities and coating build-up was investigated. The coated samples\\u000a were heat-treated in air and under argon atmosphere to investigate the wetting behaviour of the deposited Al12Si and the diffusion\\u000a processes

Kirsten Bobzin; Lidong Zhao; Thomas Schlaefer; Thomas Warda

2010-01-01

397

Empty and foam-filled circular aluminium tubes subjected to axial and oblique quasistatic loading  

Microsoft Academic Search

Tests on tubular columns made of the aluminium alloy 6060-T4 under axial and oblique, quasi-static loading have been performed. The columns were fixed at one extremity, while a concentrated force was applied at the other through a rigid collar. Empty and foam-filled columns were tested for load angles equal to 0, 5, 15 and 30 degrees with respect to the

T. Børvik; O. S. Hopperstad; A. Reyes; M. Langseth; G. Solomos; T. Dyngeland

2003-01-01

398

Quasi-static axial compression of thin-walled circular aluminium tubes  

Microsoft Academic Search

This paper presents further experimental investigations into axial compression of thin-walled circular tubes, a classical problem studied for several decades. A total of 70 quasi-static tests were conducted on circular 6060 aluminium tubes in the T5, as-received condition. The range of D\\/t considered was expanded over previous studies to D\\/t=10–450. Collapse modes were observed for L\\/D?10 and a mode classification

S. R. Guillow; G. Lu; R. H. Grzebieta

2001-01-01

399

Transition from progressive buckling to global bending of square aluminium tubes  

Microsoft Academic Search

A generic experimental study on the transition from progressive buckling to global bending during axial crushing of long square tubes was carried out. The tubes were made of the aluminium alloy 6060 T6 with 2.5 mm thickness and 80 mm outer width. Impact tests on tubes having free lengths of 1300, 1600 and 1900 mm were carried out in a pendulum accelerator. The

Ø. Fyllingen; E. C. Langmoen; M. Langseth; O. S. Hopperstad

400

Analysis of low cycle fatigue in AlMgSi aluminium alloys  

Microsoft Academic Search

In this study low-cycle fatigue tests were performed in two AlMgSi aluminium alloys with different chemical composition, namely 6082-T6 and 6060-T6 alloys, using standard round specimens and tube specimens, respectively. The tests were undertaken in strain control with a strain ratio R?=?1. The cyclic stress–strain curves were determined using one specimen for each imposed strain level. The low-cycle fatigue results

L. P. Borrego; L. M. Abreu; J. M. Costa; J. M. Ferreira

2004-01-01

401

Systematic investigation of aluminium interferences with the alkaline earths in flame atomic absorption spectrometry  

Microsoft Academic Search

Aluminium interferes with the absorption of Mg and Ca in the air-acetylene flame to such an extent that the corresponding absorbances may fall even to zero. This well-known chemical interference can be overcome with the nitrous oxide-acetylene flame, completely in the case of Mg, however only to a restricted extent in the case of Ca. Mg and Ca with concentrations

Werner Luecke

1992-01-01

402

Effect of nano-aluminium in plateau-burning and catalyzed composite solid propellant combustion  

Microsoft Academic Search

Nano-aluminium particles of ?50nm size, produced at this laboratory, are added to composite solid propellants based on ammonium perchlorate and hydroxyl-terminated poly-butadiene binder that exhibit plateau burning rate trends and those including burning rate catalysts. The nano-aluminized propellant burning rates are compared with corresponding micro-aluminized and non-aluminized ones in the 1–12MPa pressure range. The mid-pressure extinction of the matrixes containing

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

2009-01-01

403

Experimental studies on the burning of coated and uncoated micro and nano-sized aluminium particles  

Microsoft Academic Search

Two different approaches are used in this work to reduce the burning times of aluminium particles with the ultimate goal to improve the performances of solid propellants. One method is to coat the micro-sized particles by nickel, and the second is to decrease the particle sizes to nano-metric scales.A thin coating of Ni on the surface of Al particles can

P. Escot Bocanegra; C. Chauveau; I. Gökalp

2007-01-01

404

Use of acenaphthene as a carbon pyrolyzate carrier for the preparation of aluminium-carbon sorbents  

Microsoft Academic Search

The purpose of this study was a preliminary evaluation of mineral-carbon sorbents preparation possibility by the method of\\u000a thermal decomposition of a mixture of aluminium oxide or hydroxide and acenaphthene and determination of their physicochemical\\u000a properties. The conditions of carbonization were established and the changes of physicochemical properties of obtained materials\\u000a as a function of organic substance content in the

Barbara Pacewska; D. Szychowski

2008-01-01

405

Electro Discharge Machining of Titanium Nitride-Aluminium Oxide Composite for Optimum Process Criterial Yield  

Microsoft Academic Search

Titanium nitride-aluminium oxide (TiN–Al2O3) is a new generation ceramic composite material having potential for many industrial applications as it possesses high resistance to thermal degradation, anti-wear and anti-abrasion properties. But conventional machining of such ceramic composite is difficult to perform for some of its peculiar properties like anisotropy, low thermal conductivity, and abrasive nature of the reinforcing phases. In the

D. Bhaduri; A. S. Kuar; S. Sarkar; S. K. Biswas; S. Mitra

2009-01-01

406

Surface mechanical behaviour of composite Ni–P–fly ash\\/zincate coated aluminium alloy  

Microsoft Academic Search

Ni–P–fly ash coatings were produced on zincate coated 5083 wrought aluminium alloy substrates with the aid of an electroless deposition technique. Structural and chemical characterization of the produced coatings was performed with the aid of X-ray diffraction (XRD), scanning electron microscopy (SEM) and electron dispersive X-ray analysis (EDS) techniques. The Ni–P–fly ash coating was found to consist of an amorphous

C. N. Panagopoulos; E. P. Georgiou

2009-01-01

407

Different commercial grades of aluminium as galvanic anodes in alkaline zincate solutions  

Microsoft Academic Search

The self corrosion and electrochemical properties, such as open circuit potentials, polarisation characteristics and anode efficiencies, of different grades of aluminiumviz., 2S, 3S, 26S and 57S were examined in 4 M NaOH, containing 0.01 to 0.6 M zinc oxide. From these studies, 3S and 57S aluminiums were found to be the most suitable anode materials, among the different grades of

M. Paramasivam; G. Suresh; B. Muthuramalingam; S. Venkatakrishna Iyer; V. Kapali

1991-01-01

408

High accuracy non-contact ultrasonic thickness gauging of aluminium sheet using electromagnetic acoustic transducers  

Microsoft Academic Search

Aluminium sheet thickness has been calculated from ultrasonic data obtained using a send–receive, radially polarised electromagnetic acoustic transducer (EMAT). Sheets in the thickness range between 0.1 and 0.5 mm have been measured using this non-contact approach at a stand-off of up to 1.5 mm. Normal incidence shear waves generated and detected in the sheet and the resultant waveforms have been

S. Dixon; C. Edwards; S. B. Palmer

2001-01-01

409

Revealing obliterated engraved marks on high strength aluminium alloy (AA7010) surfaces by etching technique.  

PubMed

Restoration of obliterated engraved marks on high strength Al-Zn-Mg-Cu alloy (AA7010) surfaces by etching technique was studied. The alloy surfaces were mechanically engraved with some identification marks using "Gravograph". The marks were then erased by removing the metal to different levels up to and below the depth of engraving. Five metallographic reagents were tested on the obliterated surfaces by etching. The following two methods (i) immersion in 10% aq. phosphoric acid and (ii) alternate swabbing of 60% HCl and 40% NaOH were found to be quite effective to reveal the obliterated marks. These two procedures were also able to show effectively the marks obliterated by over-engraving and centre punching. Of the two techniques immersion in phosphoric acid provided more contrast. Interestingly, alternate swabbing of 60% HCl and 40% NaOH presented itself to be the common reagent for restoration on pure aluminium as well as its alloy surfaces. This is evident from our own current experiments and those of earlier researchers [G. Peeler, S. Gutowski, H. Wrobel, G. Dower, The restoration of impressed characters on aluminium alloy motor cycle frames, J. Forensic Ident. 58 (1) (2008) 27-32; M. Izhar M. Baharum, R. Kuppuswamy, A.A. Rahman, Restoration of engraved marks on aluminium surfaces by etching technique, Forensic Sci. Int. 177 (2008) 221-227]. The findings have assumed importance as engines and chassis of cars and frames of firearms are currently made of high strength aluminium alloys and recovery on these surfaces by current methods is not satisfactory. PMID:20022189

Bong, Yeu Uei; Kuppuswamy, R

2010-02-25

410

Triazole and thiazole derivatives as corrosion inhibitors for AA2024 aluminium alloy  

Microsoft Academic Search

The 1,2,4-triazole, 3-amino-1,2,4-triazole, benzotriazole and 2-mercaptobenzothiazole were evaluated in the present work as corrosion inhibitors for protection of the 2024 aluminium alloy in neutral chloride solutions. The corrosion protection performance was investigated by means of DC polarization and electrochemical impedance spectroscopy (EIS). Scanning Kelvin probe force microscopy (SKPFM) and atomic force microscopy (AFM) were used to study the evolution of

M. L. Zheludkevich; K. A. Yasakau; S. K. Poznyak; M. G. S. Ferreira

2005-01-01

411

Application of numerical simulation in the bending of aluminium-alloy profiles  

Microsoft Academic Search

This paper deals with 3D elasto-plastic finite-element analyses of the production bending of aluminium extrusions. The overall objective of the study is to determine the applicability of using the general purpose software MARC K5.2 in analysing industrial rotary draw bending and stretch bending. The main focus is placed on the effects of material behaviour, slenderness of cross-sectional members, and die

Frode Paulsen; Torgeir Welo

1996-01-01

412

Influence of shoulder geometry on microstructure and mechanical properties of friction stir welded 6082 aluminium alloy  

Microsoft Academic Search

The effect of different shoulder geometries on the mechanical and microstructural properties of a friction stir welded joints have been studied in the present paper. The process was used on 6082 T6 aluminium alloy in the thickness of 1.5mm.The three studied tools differed from shoulders with scroll and fillet, cavity and fillet, and only fillet. The effect of the three

A. Scialpi; L. A. C. De Filippis; P. Cavaliere

2007-01-01

413

Liquid-metal embrittlement of aluminium by several eutectic alloys containing zinc  

Microsoft Academic Search

The liquid-metal embrittlement of aluminium plate wetted with Cd-17% Zn, Sn-10% Zn and In-3% Zn eutectic alloy was investigated by tensile tests in the temperature range 423 to 673 K by means of scanning electron microscopy and X-ray energy dispersion. The fracture strain of specimens wetted with Cd-Zn, Sn-Zn, and In-Zn alloys decreased in the temperature ranges 553 to 623,

T. Mae; S. Hori

1991-01-01

414

Combination of various analytical techniques for speciation of low molecular weight aluminium complexes in plant sap  

Microsoft Academic Search

The possibilities for speciation of low molecular weight aluminium organic acid complexes (LMW-Al) in plant sap were investigated\\u000a by applying a combination of various chromatographic and spectroscopic techniques. The behavior of different LMW-Al complexes\\u000a was investigated in synthetic aqueous solutions on anion and cation exchange fast protein liquid chromatography (FPLC) columns\\u000a with inductively coupled plasma – atomic emission spectrometry (ICP-AES)

Tjaöa Bantan; R. Mila?i?; B. Mitrovi?; Boris Pihlar

1999-01-01

415

Synthesis and photophysical properties of aluminium tris-(4-morpholine-8-hydroxyquinoline)  

PubMed Central

Aluminium tris(4-morpholinyl-8-hydroxyquinoline) has been synthesized and characterized. The photoluminescence measurements showed that the new derivative is blue shifted and has relative photoluminescence quantum yield two times higher compared to the pristine Al tris(8-hydroxyquinoline). Deferential scanning colorimetric studies revealed that the newly synthesized Alq3 derivative in this work is amorphous material with the highest transition glass temperature value among the reported amorphous Alq3 derivatives.

Omar, Walaa A.E.

2012-01-01

416

Development of microstructure and texture during high temperature equal channel angular extrusion of aluminium  

Microsoft Academic Search

The feasibility of using the equal channel angular extrusion (ECAE) process for the breakdown of cast structures in commercial purity aluminium has been investigated. Billets of an as-cast coarse grained Al (99.7% pure) were subjected to ECAE at 500°C using a die that imparts an equivalent plastic strain of 0.67 per pass. Multiple extrusion passes were performed using two different

Uday Chakkingal; P. F. Thomson

2001-01-01

417

Fractal dimension values of cerebral and cerebellar activity in rats loaded with aluminium  

Microsoft Academic Search

Aluminium interferes with a variety of cellular metabolic processes in the mammalian nervous system and its intake might increase\\u000a a risk of developing Alzheimer’s disease (AD). While cerebral involvement even at the early stages of intoxication is well\\u000a known, the role of cerebellum is underestimated. Our aim was to investigate cerebral and cerebellar electrocortical activity\\u000a in adult male rats exposed

Goran Kekovic; Milka Culic; Ljiljana Martac; Gordana Stojadinovic; Ivan Capo; Dusan Lalosevic; Slobodan Sekulic

2010-01-01

418

CHARACTERIZATION OF CERIUM-DOPED YTTRIUM ALUMINIUM GARNET NANOPOWDERS SYNTHESIZED VIA SOL-GEL PROCESS  

Microsoft Academic Search

In this work the sol-gel process was used to prepare Ce-doped yttrium aluminium garnet (Y3Al5O12, YAG) samples. The synthesis products were characterized by infrared spectroscopy (IR), X-ray powder diffraction analysis (XRD), and transmission electron microscopy (TEM). The particle size and luminescence properties of synthesized samples were also determined. The XRD patterns of Y3Al5O12:Ce samples showed that phase purity of garnets

A. Katelnikovas; T. Jüstel; D. Uhlich; J.-E. Jørgensen; S. Sakirzanovas; A. Kareiva

2008-01-01

419

Studies on Lamb Waves in Long Aluminium Plates Generated Using Laser Based Ultrasonics  

NASA Astrophysics Data System (ADS)

This paper deals with the characterization and analysis of ultrasonic Lamb waves generated in a long aluminium plates using Laser Based Ultrasonic Technique. Nd-YAG pulsed laser is used for ultrasonic generation while He-Ne laser is used for heterodyne detection. The Lamb wave signals are analyzed using Fourier and wavelet transforms. The Lamb wave signals recorded at three diferent source detector distances are analysed and the resuls are presented.

Raghuram, V.; Shukla, R.; Pramila, T.

2010-05-01

420

The use of aluminium lake of nuclear fast red in plant material succesively with alcian blue  

Microsoft Academic Search

The successive staining alcian blue\\/aluminium lake of nuclear fast red was proved a useful tool for studies on plant root\\u000a tip. A simple and reliable procedure is given resulting in blue cell walls, almost colourless cytoplasm and red nuclei. Attempts\\u000a were made to apply spectrophotometry and paper chromatography to overcome the confusions in manufacturers’ labelling of the\\u000a dye and to

K. Beneš; M. Kamínek

1973-01-01

421

Comparison of electrodeposited and sputtered intrinsic and aluminium-doped zinc oxide thin films  

Microsoft Academic Search

Intrinsic zinc oxide (i-ZnO) and aluminium-doped ZnO (ZnO:Al) are components of high-efficiency copper indium gallium diselenide solar cells. This paper examines both of these materials grown by two different techniques, namely radio frequency sputtering and electrodeposition (ED) for comparison and a better understanding. X-ray diffraction showed all materials to be polycrystalline and hexagonal (wurtzite) ZnO. Scanning electron microscopy indicated crystallites

J. S. Wellings; A. P. Samantilleke; P. Warren; S. N. Heavens; I. M. Dharmadasa

2008-01-01

422

The Effect of Temperature on Anisotropy Properties of an Aluminium Alloy  

Microsoft Academic Search

The temperature influence on the mechanical behaviour during plastic deformation of an AA5754-O aluminium alloy has been investigated\\u000a by several experimental tests. First, monotonous tensile tests were carried out from room temperature up to 200°C with a classical\\u000a tensile machine and with a less conventional testing apparatus involving the heating of the sample by Joule effect. With this\\u000a second testing

J. Coër; C. Bernard; H. Laurent; A. Andrade-Campos; S. Thuillier

423

Mobilization of river transported colloidal aluminium upon mixing with seawater and subsequent deposition in fish gills  

Microsoft Academic Search

During flooding events, increased concentrations of gill-reactive aluminium (Al) have been identified in estuarine water causing high Al accumulation in fish gills. By in situ filtering and ultrafiltering river water (pH 5.5–6.4, 3–5 mg L?1 DOC) and continually mixing the size fractioned river water with seawater (30 in salinity), Al mobilization was studied in flow-through tank systems (6 in salinity)

Hans-Christian Teien; William J. F. Standring; Brit Salbu

2006-01-01

424

Stable and metastable phase equilibria in the chemical interaction between aluminium and silicon carbide  

Microsoft Academic Search

An experimental investigation was carried out on the Al-C-Si ternary system under atmospheric pressure and at temperatures up to 1900 K. From the results obtained, a thermodynamic model based on stable and metastable phase equilibria in the Al-C-Si ternary system was set up in order to provide a general description of the chemical interaction between aluminium and SiC. According to

J. C. Viala; P. Fortier; J. Bouix

1990-01-01

425

Mechanism and kinetics of the chemical interaction between liquid aluminium and silicon-carbide single crystals  

Microsoft Academic Search

Previous investigations of phase equilibria in the ternary system Al-C-Si have shown that silicon carbide is attacked by pure aluminium at temperatures higher or equal to 923±3 K and up to about 1600 K, according to the chemical reaction: 4Al+3SiC ? Al4C3+3Si In the present work, a study has been carried out to obtain more detailed information on the mechanism

J. C. Viala; F. Bosselet; V. Laurent; Y. Lepetitcorps

1993-01-01

426

Ageing of Adhesive Bonds with Various Surface Treatments, Part 1: Aluminium–Dicyandiamide Cured Epoxy Joints  

Microsoft Academic Search

Ageing studies on adhesive-bonded aluminium–dicyandiamide cured epoxy joints prepared using a variety of different surface treatments were carried out using 100% humidity and cycling the joints between 42–48–42 °C every hour. The pretreatments include a chromic acid, silica\\/siloxane pretreatment, nonrinse chrome pretreatment, titanium\\/zirconium (Ti\\/Zr) pretreatment, and anodised substrate with no pretreatment. Dielectric spectroscopy measurements were used to characterise the rate of

Robert Comrie; David Hayward; Richard A. Pethrick; Xiaorong Zhou; George E. Thompson

2005-01-01

427

On the interface development and fracture behaviour of roll bonded copper\\/aluminium metal laminates  

Microsoft Academic Search

Copper\\/aluminium laminates were prepared by roll bonding at 430°C with a 60% rolling reduction in a single pass. Sintering treatments at temperatures between 300 and 500°C were applied to the as-rolled laminates. The interface development and fracture behaviour of the sintered materials were studied. It was found that two major diffusion controlled interface reactions, namely interfacial phase transformations and Kirkendall

X. K. Peng; R. Wuhrer; G. Heness; W. Y. Yeung

1999-01-01

428

Characterisation of aqueous suspensions of fumed aluminium oxide in presence of two Dolapix dispersants  

Microsoft Academic Search

The stability of a fumed aluminium oxide nano powder suspended in water has been assessed through measurement of zeta potential\\u000a and streaming current, using the fact that the particles exhibit maximum repulsion at high magnitude of charge. Two commercial\\u000a dispersants belonging to a Dolapix series have been tested. Dolapix CE 64 has shown a better deflocculating action than Dolapix\\u000a A

S. Gaydardzhiev; P. Ay

2006-01-01

429

Ionization state of an aluminium X-ray laser plasma by K{alpha} spectroscopy  

SciTech Connect

An aluminium recombining X-ray laser plasma was probed by keV radiation emitted by an auxiliary plasma source to yield absorption structures on K{alpha} transitions. From this technique we obtain the spatial distribution of the relative abundances of He- to B-like ions at different times during plasma cooling. He-like and Li-like ions are found to exist further from the target than predicted by the hydrocode, explaining previous gain measurements.

Klisnick, A.; Chenais-Popovics, C.; Back, C. A.; Zeitoun, P.; Renaudin, P.; Rancu, O.; Gauthier, J. C.; Jaegle, P. [Laboratoire de Spectroscopie Atomique et Ionique, Universite Paris-Sud, Bat. 350, 91405 Orsay Cedex (France); LULI: CNRS National Facility, Laboratoire pour l'Utilisation des Lasers Intenses, Ecole Polytechnique, 91128 Palaiseau Cedex (France); Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94550 (United States); Laboratoire de Spectroscopie Atomique et Ionique, Universite Paris-Sud, Bat. 350, 91405 Orsay Cedex (France); LULI: CNRS National Facility, Laboratoire pour l'Utilisation des Lasers Intenses, Ecole Polytechnique, 91128 Palaiseau Cedex (France); Laboratoire de Spectroscopie Atomique et Ionique, Universite Paris-Sud, Bat. 350, 91405 Orsay Cedex (France)

1995-05-01

430

Relationship between cutting force and PCD cutting tool wear in machining silicon carbide reinforced aluminium  

Microsoft Academic Search

This paper presents a study of the relationship between cutting forces and tool wear of polycrystalline diamond (PCD), measured when machining the composite A356\\/20\\/SiCp-T6 (aluminium with 7.0% silicon, 0.4% magnesium reinforced with 20vol.% particles of silicon carbide (SiC); heat treatment: solutionising and ageing T6 for 5h at 154°C). The experimental work was developed considering the drilling and turning operations, through

J Paulo Davim; A Monteiro Baptista

2000-01-01

431

Influence of zinc on calcium-dependent signal transduction pathways during aluminium-induced neurodegeneration.  

PubMed

Metals perform important functions in the normal physiological system, and alterations in their levels may lead to a number of diseases. Aluminium (Al) has been implicated as a major risk factor, which is linked to several neurodegenerative diseases including Alzheimer's disease and Parkinson's disease. On the other hand, zinc (Zn) is considered as a neuromodulator and an essential dietary element that regulates a number of biological activities in our body. The aim of the present study was to investigate the effects of Zn supplementation, if any, in ameliorating the changes induced by Al on calcium signalling pathway. Male Sprague Dawley rats weighing 140-160 g were divided into four different groups viz.: normal control, aluminium treated (100 mg/kg b.wt./day via oral gavage), zinc treated (227 mg/l in drinking water) and combined aluminium and zinc treated. All the treatments were carried out for a total duration of 8 weeks. Al treatment decreased the Ca(2+) ATPase activity whereas increased the levels of 3', 5'-cyclic adenosine monophosphate, intracellular calcium and total calcium content in both the cerebrum and cerebellum, which, however, were modulated upon Zn supplementation. Al treatment exhibited a significant elevation in the protein expressions of phospholipase C, inositol triphosphate and protein kinase A but decreased the expression of protein kinase C, which, however, was reversed upon Zn co-treatment. Al treatment also revealed alterations in neurohistoarchitecture in the form of calcium deposits, which were improved upon zinc co-administration. The present study, therefore, suggests that zinc regulates the intracellular calcium signalling pathway during aluminium-induced neurodegeneration. PMID:24500000

Singla, Neha; Dhawan, D K

2014-10-01

432

Soft X-ray emission spectra of non-dilute aluminium-magnesium alloys  

Microsoft Academic Search

Aluminium and magnesium LII, III emission spectra have been obtained from the inter-metallic compounds Al2Mg2 and Al12Mg17 and also from the pure metals. A progressive change of band shapes emerges. On alloying, the Al band develops a low energy hump, more prominent in the more dilute alloy, accompanied by a decline in the peak at the Fermi edge. With increasing

A. Appleton; C. Curry

1965-01-01

433

Characteristics of Fatigue-activated Creep in an Aluminium-Magnesium Alloy  

Microsoft Academic Search

EXPERIMENTS have been conducted on thin-walled tubes of an aluminium-magnesium alloy (3.08 per cent magnesium, 0.3 iron, 0.44 manganese, 0.18 silicon) under conditions of simple shear. Two tubes aligned on a common axis are used for each test, the torque being applied through a disk connected to both tubes. The assembly is mounted in a thermostatically controlled enclosure, and to

A. J. Kennedy

1962-01-01

434

Pretreatment effects on the electrochemical responses for aluminium–magnesium alloy AA5083 corrosion behaviour  

Microsoft Academic Search

Electrochemical investigations on aluminium alloy corrosion in a sodium chloride solution have been performed by potentiostatic\\u000a and potentiodynamic (electrochemical impedance spectroscopy) methods. Measurements have been obtained after mechanical polishing\\u000a or electrochemical stripping in deaerated or not solution. All the results are strongly depending on the pretreatments that\\u000a are undergone in the laboratory before the experimental measurements. Mechanical polishing induces huge

Nacer Zazi; Ahcène Bouabdallah; Omar Aaboubi; J.-P. Chopart

2010-01-01

435

Effect of explosive bonds on acoustic loss of aluminium-magnesium alloys  

Microsoft Academic Search

The amplitude-independent mechanical quality factors of the commercial aluminium-magnesium alloys 5056 and 5456 were measured from 50 mK to 300 K in torsional mechanical resonators in which the rotation axis coincides with an essentially flat explosive-bond plane. The 1 kHz resonators were configured to minimize extraneous internal friction effects. The results are compared with those obtained in similar experiments on

W. Duffy; S. Dalal

1996-01-01

436

Mechanism of aluminium spike formation and dissipation in electrothermal atomic absorption spectrometry  

NASA Astrophysics Data System (ADS)

The mechanism of aluminium spike formation and dissipation of aluminium atoms in electrothermal atomization absorption spectrometry has been investigated using two different approaches. The first approach employs a graphite electrothermal atomizer coupled to an inductively coupled plasma mass spectrometer (ICP-MS) in a configuration that allows simultaneous measurement of atomic, or molecular, absorption signals and mass spectrometric signals. Aluminium sub-oxide (AlO and Al 2O) and CO(g) spikes in ICP-MS are correlated with the appearance of both Al atom spikes and Al-containing molecule spikes in absorption spectrometry. The aluminium carbide (AlC 2) signal in ICP-MS is not coincident with the appearance of either Al atom spikes or Al-containing molecule spikes in absorption spectrometry. The second approach uses two different imaging systems, i.e. shadow spectral filming (SSF) and shadow spectral digital imaging (SSDI), to provide temporally and spatially resolved absorption profiles of Al atoms and Al-containing molecules during Al spike formation and dissipation. The transverse cross-sectional distribution of Al atoms and of Al-containing molecules in the graphite furnace are complementary to one another for both wall and platform atomization. The highest concentration of Al atoms is near the graphite surface, whereas the highest concentration of Al-containing molecular species is at the centre of the graphite tube. The Al-containing molecules observed in both wall and platform atomization consist of both gaseous Al-molecules and a non-uniformly distributed cloud of finely dispersed Al 2O 3(s,1) particles. A mechanism of formation that is consistent with the above experimental observations is presented. It is proposed that Al atom spikes are formed from gaseous Al 2O precursors and that this reaction is triggered by the formation of a molten, condensed-phase Al 4C 3 melt.

Lamoureux, Marc M.; Chakrabarti, C. L.; Hutton, J. Craig; Gilmutdinov, Albert Kh.; Zakharov, Yuri A.; Grégoire, D. Conrad

1995-12-01

437

Technological approaches by laser beam welding of aluminium alloys and influence of errors in manufacturing process  

NASA Astrophysics Data System (ADS)

The explosive development of modern manufacturing technologies, particularly the laser beam manufacturing, has raised new challenges in the field of research. The laser beam welding process may be influenced by errors appearing from different causes. In this paper the authors present the influence of errors during the experiments regarding the laser beam welding of aluminium alloy. In the physical experiment, two major geometric welding characteristics (the welding surface and the welding width) of an aluminium alloy AlMgSi 1 were measured at different welding speeds, using a solid state laser Nd:YAG, HL 4006D. With the aim of obtaining the best results, a CCD-Camera was assembled on the device allowing to capture the most accurate photos from the experiments. The appearance of errors is more likely to be found in the domain of high rate welding speeds than in those of low welding speeds. The data analysis based on the dispersion criterion is useful to characterize the influence of thermal parameters of aluminium alloy upon the laser beam welding surface and width, which may be extended to other new materials with the same characteristics. The present researches started together with the University of Stuttgart will be continued at the Technical University of Cluj-Napoca with a new laser equipment.

Popa, Marcel S.; Rus, Calin; Preja, Dan; Moldovan, Raul

2005-02-01

438

Electrodeposition of iron and iron-aluminium alloys in an ionic liquid and their magnetic properties.  

PubMed

In this work we show that nanocrystalline iron and iron-aluminium alloys can be electrodeposited from the ionic liquid 1-butyl-1-methylpyrrolidinium trifluoromethylsulfonate, [Py1,4]TfO, at 100 °C. The study comprises CV, SEM, XRD, and magnetic measurements. Two different sources of iron(ii) species, Fe(TfO)2 and FeCl2, were used for the electrodeposition of iron in [Py1,4]TfO. Cyclic voltammetry was employed to evaluate the electrochemical behavior of FeCl2, Fe(TfO)2, and (FeCl2 + AlCl3) in the employed ionic liquid. Thick iron deposits were obtained from FeCl2/[Py1,4]TfO at 100 °C. Electrodeposition of iron-aluminium alloys was successful in the same ionic liquid at 100 °C. The morphology and crystallinity of the obtained deposits were investigated using SEM and XRD, respectively. XRD measurements reveal the formation of iron-aluminium alloys. First magnetic measurements of some deposits gave relatively high coercive forces and power losses in comparison to commercial iron-silicon samples due to the small grain size in the nanometer regime. The present study shows the feasibility of preparing magnetic alloys from ionic liquids. PMID:24715034

Giridhar, P; Weidenfeller, B; El Abedin, S Zein; Endres, F

2014-05-28

439

Regular consumption of a silicic acid-rich water prevents aluminium-induced alterations of nitrergic neurons in mouse brain: histochemical and immunohistochemical studies.  

PubMed

Silicon is not generally considered an essential nutrient for mammals and, to date, whether it has a biological role or beneficial effects in humans is not known. The results of a number of studies suggest that dietary silicon supplementation might have a protective effect both for limiting aluminium absorption across the gut and for the removal of systemic aluminium via the urine, hence, preventing potential accumulation of aluminium in the brain. Since our previous studies demonstrated that aluminium exposure reduces the number of nitrergic neurons, the aim of the present study was to compare the distribution and the morphology of NO-containing neurons in brain cortex of mice exposed to aluminium sulphate dissolved in silicic acid-rich or poor drinking water to assess the potential protective role of silicon against aluminium toxicity in the brain. NADPH-d histochemistry and nNOS immunohistochemistry showed that high concentrations of silicon in drinking water were able to minimize the impairment of the function of nitrergic neurons induced by aluminium administration. We found that silicon protected against aluminium-induced damage to the nitrergic system: in particular, we demonstrated that silicon maintains the number of nitrergic neurons and their expression of nitrergic enzymes at physiological levels, even after a 12 and 15 month exposure to aluminium. PMID:22763878

Foglio, E; Buffoli, B; Exley, C; Rezzani, R; Rodella, L F

2012-08-01

440

Sponsors of CIEEDAC: Natural Resources Canada, Canadian Industry Program for Energy Conservation, Aluminium Industry Association, Canadian Petroleum Products Institute, Canadian Portland Cement Association, Canadian Pulp  

E-print Network

, Aluminium Industry Association, Canadian Petroleum Products Institute, Canadian Portland Cement Association increases, alternative collection of industry specific data may be carried out through ICE, considered

441

The effect of Mg addition on microstructure and tensile and stress rupture properties of a P/M Al-Fe-Ce alloy  

SciTech Connect

Dispersion strengthened Aluminium alloys based on Al-TM (TM = transition metal) type systems are being developed for elevated temperature structural applications in aerospace at temperatures up to 623K as possible substitutes for the more expensive and refractory Ti alloys currently used. Alloy systems containing transition metals such as Fe, Ni, V, Cr, Zr, Mo and Ti with possible additions of Si and Ce (or misch metal) have been investigated. Al-Fe-Ce alloys belong to this class of dispersion strengthened aluminium alloys which are strengthened primarily by ternary Al-Fe-Ce precipitates. The matrix in this case is almost pure aluminium. Further strengthening of the alloy may therefore be possible by addition of elements such as Mg which impart solid solution strengthening. This should also result in enhancement in elevated temperature strength and stress rupture properties. It is reported that the addition of Mg to Al-Fe-Mm (Mm = misch metal) alloy does not result in formation of new phases in melt spun ribbons even after annealing at 773K thereby confirming that Mg is retained in solid solution. The aim of the present work is to investigate the effect of Mg addition on the microstructure and tensile and stress rupture properties of an Al-Fe-Ce alloy.

Prakash, U.; Raghu, T.; Kamat, S.V.; Gokhale, A.A. [Defence Metallurgical Research Lab., Hyderabad (India)] [Defence Metallurgical Research Lab., Hyderabad (India)

1998-09-04

442

Determination of aluminium in iron, steel and ferrous and non-ferrous alloys by atomic-absorption spectrophotometry after a mercury-cathode separation and extraction of the aluminium-acetylacetone complex.  

PubMed

A method for determining 0.0005% or more of total aluminium in high- and low-alloy steels, iron and ferrovanadium is described. Iron, chromium and other matrix elements are separated from aluminium by electrolysis with a mercury cathode and aluminium is separated from tungsten, titanium, vanadium and phosphate by chloroform extraction of its acetylacetone complex at pH 6.5 from an ammonium acetate-hydrogen peroxide medium. The extract is evaporated to dryness and organic material is destroyed with nitric and perchloric acids. Aluminium is determined by atomic-absorption spectrophotometry in a nitrous oxide-acetylene flame, at 309.3 nm, in a 5% v/v perchloric acid medium containing 1000 mug of sodium per ml. Acid-soluble and acid-insoluble aluminium can also be determined. The method is also applicable to copper- and nickel-base alloys. Results obtained by this method are compared with those obtained spectrophotometrically with Pyrocatechol Violet, after the separations described above followed by the separation of the residual co-extracted iron and copper by a combined ammonium pyrrolidinedithiocarbamate-cupferron-chloroform extraction from 10% v/v hydrochloric acid medium. PMID:18963054

Donaldson, E M

1981-07-01

443

Writing subwavelength-sized structures into aluminium films by thermo-chemical aperture-less near-field optical microscopy.  

PubMed

An optical near-field at the tip of an atomic force microscope probe is utilised to pattern aluminium thin films on glass substrates by photo-thermally induced corrosion in water. Aluminium forms a thin passivating oxide layer when immersed into neutral water at room temperature. Owing to the high energy density of the near-field, the metal below the probe tip can be heated to 100 degrees C due to absorption of the light, which then provokes breakdown of the passivation and metal corrosion. The localised near-field is generated by tip-induced enhancement of an evanescent field originating from a laser beam, that is totally internally reflected at the glass-aluminium-water interface. The process is governed by surface plasmons excited in the aluminium film by the evanescent waves and the field enhancement of the probe tip. Holes of 40 nm diameter and lines below 100 nm width have been written into a 20-nm-thick aluminium film. Applications of the scanning probe lithography process may include the one-step fabrication of point contacts or contact masks for near-field optical lithography and reactive ion etching. PMID:15231339

Haefliger, D; Stemmer, A

2004-08-01

444

Nucleation of the diamond phase in aluminium-solid solutions  

NASA Technical Reports Server (NTRS)

Precipitation was studied from fcc solid solutions with silicon, germanium, copper and magnesium. Of all these elements only silicon and germanium form diamond cubic (DC) precipitates in fcc Al. Nucleation of the DC structure is enhanced if both types of atom are dissolved in the fcc lattice. This is interpreted as due to atomic size effects in the prenucleation stage. There are two modes of interference of fourth elements with nucleation of the DC phase in Al + Si, Ge. The formation of the DC phase is hardly affected if the atoms (for example, copper) are rejected from the (Si, Ge)-rich clusters. If additional types of atom are attracted by silicon and/or germanium, DC nuclei are replaced by intermetallic compounds (for example Mg2Si).

Hornbogen, E.; Mukhopadhyay, A. K.; Starke, E. A., Jr.

1993-01-01

445

The Influence of Strain Rate Variations on the Appearance of Serrated Yielding in 2024-T3 Al-Clad Aluminium Alloy  

SciTech Connect

To avoid failure during the stretch forming process using manual control, machine operators tend to achieve the final form using a stop-start approach. It was observed that when approaching full form, stretcher-strain marks appeared on the surface of the part if the operator stopped and restarted the forming operation. In order to investigate this phenomenon, a series of tensile tests was conducted using two batches of 2024-T3 aluminium alloy. The specimens were tested using several different strain rates, representative of those used on the shop floor. Additional tests were conducted involving a series of pauses under displacement control at differing levels of strain and strain rate. In the uninterrupted tests for the two batches of 2024-T3 material tested, serrated yielding was observed just prior to failure. However for the tests in which there was a pause in displacement, the material consistently exhibited serrated yielding when the crosshead began to move again. These results indicate that the pause provides an opportunity for strain ageing and pinning of the dislocations resulting in serrated yielding of this alloy. In order to avoid serrated yielding, stretch forming operations using 2024-T3 aluminium should be conducted at a constant strain rate without interruption. This also has far reaching implications for those involved in the production and testing of these alloys. The test programme described represents an initial attempt to investigate a phenomenon noted during an industrial forming process and should be extended to analyse the affect of strain path changes on the occurrence of serrated yielding.

Leacock, Alan G.; McMurray, Robert J.; Brown, D. [Advanced Metal Forming Research Group, Nanotechnology and Advanced Materials Research Institute, University of Ulster, Shore Road, Newtownabbey, Co. Antrim, N. Ireland, BT370QB (United Kingdom); Poston, Ken [Bombardier Aerospace, Airport Road, Co. Antrim, N. Ireland, BT3 9DZ (United Kingdom)

2007-04-07

446

5. Building #3, original structure, second addition, and first addition ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. Building #3, original structure, second addition, and first addition (from right to left), south and east sides, looking northwest. - S. W. Shattuck Chemical Company, Incorporated, Building No. 3, 1805 South Bannock Street, Denver, Denver County, CO

447

Influence of Aluminium on the Restoration Potential of a Terrestrial Vascular Plant, Portulaca Oleracea L. as a Biomonitoring Tool of Fresh Water Aquatic Environments  

Microsoft Academic Search

In the present study, the influence of aluminium on the regeneration potential of leaf and stem-cuttings of Portulaca oleracea was studied in order to identify a terrestrial plant species as an alternate biomonitoring toolof fresh water environment. The leaves and stem cuttings of theterrestrial plant, P. oleracea grew well in the distilled water producing adventitious and lateral roots. The aluminium

S. Anandi; P. Thangavel; V. Subburam

2002-01-01

448

Simultaneous determination of lead, nickel, tin and copper in aluminium-base alloys using slurry sampling by electrical discharge and multielement ETAAS.  

PubMed

The simultaneous multielement determination of Pb, Sn, Ni and Cu in aluminium alloys by electrothermal atomic absorption spectrometry (ETAAS) was performed by a quick method using slurry sampling. The metallic colloidal slurries were obtained by an electrical discharge operated in liquid medium. In this work, the effects of aluminium were evaluated and the results show that it causes a strong retention of Pb, Ni and Cu at low pyrolysis temperatures which is overcome by employing high pyrolysis temperatures. Aluminium also significantly improves the thermal stabilisation of Pb and Sn, it being possible to reach pyrolysis temperatures of 1100 and 1300 degrees C, respectively. Such stabilisation indicates that the performance of aluminium as a matrix modifier for Pb is better than that obtained using phosphate and magnesium nitrate without substantial changes of the figures of merit. The effects of aluminium on the atomisation characteristics of the elements and those coming from the simultaneous multielement determination on the figures of merit of the elements are also discussed. In this work, a calibration procedure involving a matrix matching method with aqueous aluminium standards is proposed as a simple and efficient way to solve the inconveniences originated by the aluminium matrix. The proposed method was applied to the simultaneous multielement determination of several aluminium-base alloy standards giving results well within the recommended values. PMID:18969226

Carrión, Nereida; Itriago, Ana M; Alvarez, Maria A; Eljuri, Elias

2003-12-01

449

Predicted intake of trace elements and minerals via household drinking water by 6-year-old children from Kraków, Poland. Part 3: Aluminium  

Microsoft Academic Search

In order to assess aluminium intake via drinking water by children, approximately 400 households in urban, peripheral, and rural areas were investigated. The study comprised about 200 children (5–7 years old) in the period between 2000 and 2001. The samples of drinking water were collected by a double sampling method (morning and evening). Aluminium was measured by graphite furnace-atomic absorption

H. Barton

2008-01-01

450

On the optical properties of undoped and rare-earth-doped yttrium aluminium garnet single This article has been downloaded from IOPscience. Please scroll down to see the full text article.  

E-print Network

On the optical properties of undoped and rare-earth-doped yttrium aluminium garnet single crystals.1088/0022-3727/45/1/015103 On the optical properties of undoped and rare-earth-doped yttrium aluminium garnet single crystals C R Varney, D aluminium garnets Y3Al5O12 (YAG) are important photonic materials with a wide range of applications

Collins, Gary S.

451

Investigation of the particle size distribution of the ejected material generated during the single femtosecond laser pulse ablation of aluminium  

NASA Astrophysics Data System (ADS)

Single femtosecond laser pulses are employed to ablate an aluminium target in vacuum, and the particle size distribution of the ablated material deposited on a mica substrate is examined with atomic force microscopy (AFM). The recorded AFM images show that these particles have a mean radius of several tens of nanometres. It is also determined that the mean radius of these deposited nanoparticles increases when the laser fluence at the aluminium target increases from 0.44 J/cm2 to 0.63 J/cm2. The mechanism of the laser-induced nanoparticle generation is thought to be photomechanical tensile stress relaxation. Raman spectroscopy measurements confirm that the nanoparticles thus produced have the same structure as the bulk aluminium.

Wu, Han; Zhang, Nan; Zhu, Xiaonong

2014-10-01

452

Development and Mechanical Behavior of FML/Aluminium Foam Sandwiches  

NASA Astrophysics Data System (ADS)

In this study, the Fiber-Metal Laminates (FMLs) containing glass fiber reinforced polypropylene (GFPP) and aluminum (Al) sheet were consolidated with Al foam cores for preparing the sandwich panels. The aim of this article is the comparison of the flexural properties of FML/Al foam sandwich panels bonded with various surface modification approaches (silane treatment and combination of silane treatment with polypropylene (PP) based film addition). The FML/foam sandwich systems were fabricated by laminating the components in a mould at 200 °C under 1.5 MPa pressure. The energy absorbtion capacities and flexural mechanical properties of the prepared sandwich systems were evaluated by mechanical tests. Experiments were performed on samples of varying foam thicknesses (8, 20 and 30 mm). The bonding among the sandwich components were achieved by various surface modification techniques. The Al sheet/Al foam sandwiches were also consolidated by bonding the components with an epoxy adhesive to reveal the effect of GFPP on the flexural performance of the sandwich structures.

Ba?türk, S. B.; Tano?lu, M.

2013-10-01

453

Acoustic neuroma: potential risk factors and audiometric surveillance in the aluminium industry  

PubMed Central

Objectives To look for an association between acoustic neuroma (AN) and participation in a hearing conservation programme (HCP) and also for an association between AN and possible occupational risk factors in the aluminium industry. Methods We conducted a case–control analysis of a population of US aluminium production workers in 8 smelters and 43 other plants. Using insurance claims data, 97 cases of AN were identified between 1996 and 2009. Each was matched with four controls. Covariates included participation in a HCP, working in an aluminium smelter, working in an electrical job and hearing loss. Results In the bivariate analyses, covariates associated with AN were participation in the HCP (OR=1.72; 95% CI 1.09 to 2.69) and smelter work (OR=1.88; 95% CI 1.06 to 3.36). Electrical work was not significant (OR=1.60; 95% CI 0.65 to 3.94). Owing to high participation in the HCP in smelters, multivariate subanalyses were required. In the multivariate analyses, participation in the HCP was the only statistically significant risk factor for AN. In the multivariate analysis restricted to employees not working in a smelter, the OR was 1.81 (95% CI 1.04 to 3.17). Hearing loss, an indirect measure of in-ear noise dose, was not predictive of AN. Conclusions Our results suggest the incidental detection of previously undiagnosed tumours in workers who participated in the company-sponsored HCP. The increased medical surveillance among this population of workers most likely introduced detection bias, leading to the identification of AN cases that would have otherwise remained undetected. PMID:25015928

Taiwo, Oyebode; Galusha, Deron; Tessier-Sherman, Baylah; Kirsche, Sharon; Cantley, Linda; Slade, Martin D; Cullen, Mark R; Donoghue, A Michael

2014-01-01

454

Electron beam evaporation of aluminium with a porous tantalum rod in melt pool  

NASA Astrophysics Data System (ADS)

For most metals, evaporation owing to electron beam heating proceeds in an efficient manner at temperatures substantially higher than the melting point. This is particularly true for aluminium, which has a large separation of melting and boiling point (>1000 K). This leads to situations where convective heat transfer plays an increasingly dominant role with increase in incident e-beam power and puts a limit on the surface temperature (and consequently the atomic flux). To mitigate this heat drain, a porous tantalum rod (~35% porosity) was placed at the point of e-beam impact to act as a convection arrestor and a wick within the aluminium melt pool. The molten aluminium around the porous rod was found to ooze through the capillaries of the porous rod to emerge as a vapour stream. On measuring the atomic flux and surface temperature at e-beam powers (below a value where tantalum softens), it was found that ~50% higher temperature was reached with the tantalum rod than without it. Also, for generating the same atomic flux, the required e-beam power in the case of the porous rod was about one-sixth of the e-beam power required without the rod. Such an efficient evaporation has been reported earlier but without any qualification on the ion fraction of the vapour stream. In our experiment, the ion content in the vapour stream was measured. It was found that the ionization yield in the case of the porous rod was about five times the yield without the rod. Estimation of ionization yields owing to various processes led to the conclusion that higher ionization in the case of the porous rod can be attributed to a higher emission of secondary electrons from the porous rod causing enhanced electron impact ionization.

Dikshit, B.; Zende, G. R.; Bhatia, M. S.; Suri, B. M.

2005-07-01

455

Pulmonary disease from occupational exposure to an artificial aluminium silicate used for cat litter.  

PubMed Central

All available workers engaged in bagging an artificial crystalline aluminium silicate--the kiln-dried residue from the calcining and water extraction of alunite (a hydrated sulphate of aluminium and potassium) that is currently classified as a nuisance dust--were studied after a complaint of respiratory and systemic symptoms, including arthritis, by an employee of the factory, who showed physiological and radiographic evidence of diffuse pulmonary fibrosis and in whom lung biopsy showed diffuse fibrosis with granulomas. Inhalation challenge produced a transient decrease in transfer factor and transfer factor standardised for alveolar volume. Twenty-five subjects were known to have been exposed at some time to the dust of alunite-residue. Of the 17 who could be contacted, all agreed to attend for respiratory questionnaire and occupational history, pulmonary function testing (spirometry, lung volumes, gas transfer), and posteroanterior chest radiograph. Six subjects considered that occupational exposure to the dust was responsible for respiratory symptoms. Three subjects had abnormality of the chest radiograph consistent with pulmonary fibrosis. The mean percentage of predicted transfer factor standardised for effective alveolar volume was 71.1% in subjects with abnormal chest radiographs and 86.6% in subjects with normal radiographs (p = 0.10). There was a trend in the correlation between the percentage of predicted transfer factor standardised for effective alveolar volume and total dust exposure (sum of the products of grade of severity of each exposure period and duration of each exposure period in months) (r = 0.40 p = 0.10). This study suggests that there may be a relation between inhalation of the dust of this form of aluminium silicate and pulmonary fibrosis. Images PMID:7448131

Musk, A W; Greville, H W; Tribe, A E

1980-01-01

456

[Survival after oral poisoning with insecticide against moles containing aluminium phosphide].  

PubMed

A 31-year-old man presented with abdominal pain and vomiting with a smell of garlic and rotten fish. He was brought to the ER being circulatory affected, metabolic acidotic and he developed more episodes of arrhythmia. Oral poisoning with aluminium phosphide is a very serious condition due to release of the toxic phosphine gas. Treatment is symptomatic. To avoid contamination of the staff is it important to use air-tight containers for excretions and furthermore to use chemical clothing and breathing protection. PMID:23763928

Møller Eggertsen, Peter; Kristensen, Asgerd Krogh; Bredahl, Claus

2013-06-10

457

Rapid and selective chelatometric titration of aluminium in non-ferrous alloys.  

PubMed

A rapid chelatometric method for the determination of Al (4-20%) in magnesium, copper and chromium-aluminium-iron alloys is proposed. HEDTA is used as titrant and Zn solution as back-titrant, with hydrazidazol as indicator. Mn(II), Cu(II), Cd, Zn, Pb, Co(II), Ni, Hg(II), Fe(III), Bi, Cr(III), Sb(III), Ce(III), La, Sn(IV), Ti(IV), Zr and Mo(VI) do not interfere. High selectivity is achieved by a combination of group separation, masking and interference correction. The coefficient of variation varies from 0.2 to 1%. PMID:18963965

Nan, Z; Yuan-Xiang, G; Zhi-Ren, L; Eei-Yong, C

1985-12-01

458

Formation of intermetallic phases in diffusion-welded joints of aluminium and magnesium alloys  

Microsoft Academic Search

Basic research has been done on diffusion-welded joints with the overall aim of an adjusted interface design. The phase formation\\u000a of aluminium alloy\\/magnesium alloy bonds has been revealed by X-ray diffraction, energy-dispersive spectroscopy and electron\\u000a back-scatter diffraction. The presence of Al12Mg17 and Al3Mg2 phases in a bi-layer has been confirmed. The distribution and microstructure of the formed intermetallics and the

D. Dietrich; D. Nickel; M. Krause; T. Lampke; M. P. Coleman; V. Randle

2011-01-01

459

Aluminium speciation in streams and lakes of the UK Acid Waters Monitoring Network, modelled with WHAM.  

PubMed

The Windermere Humic Aqueous Model (WHAM) incorporating Humic Ion-Binding Model VI was applied to analytical data from the United Kingdom Acid Waters Monitoring Network, collected for 22 streams and lakes over the period 1988-2007, to calculate the chemical speciation of monomeric aluminium (Al(mon)) in 3087 water samples. Model outputs were compared with analytical measurements of labile and non-labile Al(mon) concentrations, the former being equated with inorganic forms of Al(mon) and the latter with organically-complexed metal. Raw analytical data were used, and also data produced by applying a correction for the possible dissociation of organically-complexed Al(mon), and therefore its underestimation, during passage through the analytical cation-exchange column. Model calibration was performed by finding the conversion factor, F(FADOC), between the concentration of isolated fulvic acid, with default ion-binding properties, required by the model, and the measured concentration of dissolved organic carbon, [DOC]. For both uncorrected and corrected data, the value of F(FADOC) for streams was greater than for lakes, indicating greater binding activity towards aluminium. Model fits were better using uncorrected analytical data, but the values of F(FADOC) obtained from corrected data agreed more closely with previous estimates. The model provided reasonably good explanations of differences in aluminium speciation between sampling sites, and of temporal variations at individual sites. With total monomeric concentration as input, WHAM calculations might substitute for analytical speciation measurements, or aid analytical quality control. Calculated Al(3+) activities, a(Al3+), showed a pH-dependence similar to that previously found for other surface waters, and the modelling exercise identified differences between waters of up to two orders of magnitude in the value of a(Al3+) at a given pH. The model gives the net charge of dissolved organic matter, which is calculated to have risen significantly at 15 of the AWMN sites, due to increases in pH and decreases in aluminium concentration. PMID:21277614

Tipping, E; Carter, H T

2011-03-15

460

Erbium-doped yttrium aluminium garnet ablative laser treatment for endogenous ochronosis.  

PubMed

Ochronosis is a rare disease characterised clinically by bluish-grey skin discolouration and histologically by yellow-brown pigment deposits in the dermis. It occurs in endogenous and exogenous forms. Endogenous ochronosis, also known as alkaptonuria, is an autosomal recessive disease of tyrosine metabolism, resulting in the accumulation and deposition of homogentisic acid in connective tissue. We report a case of facial endogenous ochronosis and coexistent photodamage, which was successfully treated with erbium-doped yttrium aluminium garnet laser resurfacing and deep focal point treatment to remove areas of residual deep pigment. PMID:25302636

Chaptini, Cassandra; Huilgol, Shyamala C

2014-10-10

461

Protection of 2024-T3 aluminium alloy by corrosion resistant phytic acid conversion coating  

NASA Astrophysics Data System (ADS)

The corrosion protection properties of environmentally friendly phytic acid conversion coatings were studied on 2024-T3 aluminium alloy. The films were prepared under acidic conditions with various pH values and characterised by SEM, EDS, ATR-FTIR and electrochemical techniques. The results indicate that the conversion coatings obtained by immersing the alloy in phytic acid solutions at pH from 3 to 5.5 provide excellent corrosion resistance. ATR-FTIR confirms that the film is formed by deposition of reaction products between Al3+ and phosphate groups in phytic acid molecules. The conformation models of the deposition film are proposed.

Shi, Hongwei; Han, En-Hou; Liu, Fuchun; Kallip, Silvar

2013-09-01

462

Multicycle water vapour stability of microporous breathing MOF aluminium isophthalate CAU-10-H.  

PubMed

The hydrothermal stability of aluminium hydroxide isophthalate MOF CAU-10-H was proven, under humid multi-cycling conditions. Detailed in situ thermogravimetric measurements and in situ powder X-ray diffraction analysis during water ad-/desorption were used. A reversible structural change during adsorption was detected and thereby exemplified the robustness of breathing-like MOFs over 700 water vapour ad/desorption cycles. In combination with high water adsorption capacity, hydrophilic CAU-10-H is the first breathing-like MOF with a structural change which is a promising candidate for the use in heat transformation processes. PMID:25189376

Fröhlich, Dominik; Henninger, Stefan Kai; Janiak, Christoph

2014-11-01

463

Research of aluminium alloy aerospace structure aperture measurement based on 3D digital speckle correlation method  

NASA Astrophysics Data System (ADS)

In this paper, the aperture change of the aluminium alloy aerospace structure under real load is researched. Static experiments are carried on which is simulated the load environment of flight course. Compared with the traditional methods, through experiments results, it's proved that 3D digital speckle correlation method has good adaptability and precision on testing aperture change, and it can satisfy measurement on non-contact,real-time 3D deformation or stress concentration. The test results of new method is compared with the traditional method.

Bai, Lu; Wang, Hongbo; Zhou, Jiangfan; Yang, Rong; Zhang, Hui

2014-11-01

464

Uptake and sorption of aluminium and fluoride by four green algal species  

PubMed Central

Background We examined the uptake and sorption of aluminium (Al) and fluoride (F) by green algae under conditions similar to those found in the effluents of the aluminium industry. We took into account the speciation of Al in the medium since Al can form stable complexes with F and these complexes may play a role in the uptake and sorption of Al. We compared the capacity of four species of green algae (i.e. Chlamydomonas reinhardtii, Pseudokirchneriella subcapitata, Chlorella vulgaris, and Scenedesmus obliquus) to accumulate and adsorb Al and F. The selected algae were exposed during 4 days, covering all growth phases of algae, to a synthetic medium containing Al and F at pH 7.0. During this period, dissolved Al as well as cellular growth were followed closely. At the end of the exposure period, the solutions were filtered in order to harvest the algal cells. The cells were then rinsed with enough ethylene diaminetetraacetic acid to remove loosely bound ions from the algal surface, determined from the filtrates. Finally, the filters were digested in order to quantify cellular uptake. Results Little difference in Al removal was observed between species. Aluminium sorption (15%) and uptake (26%) were highest in P. subcapitata, followed by C. reinhardtii (7% and 17% respectively), S. obliquus (13% and 5%), and C. vulgaris (7% and 2%). However, none of these species showed significant uptake or sorption of F. We also studied the influence of pH on the uptake and sorption of Al and F by P. subcapitata. We measured a combined uptake and sorption of Al of 50% at pH 7.5, of 41% at pH 7.0, and of 4% at pH 5.5. Thus, accumulation was reduced with acidification of the medium as expected by the increased competition with protons and possibly by a reduced bioavailability of the Al-F complexes which dominated the solution at low pH. Conclusion Out of the four tested species, P. subcapitata showed the highest sorption of aluminium and fluoride under our test conditions. These results provide key information on the development of an environmental biotechnology which can be applied to industrial effluents. PMID:24485034

2014-01-01

465

Controlling the anodizing conditions in preparation of an nanoporous anodic aluminium oxide template  

NASA Astrophysics Data System (ADS)

Porous anodic aluminium oxide (AAO) template is commonly used in the synthesis of one-dimensional nanostructures, such as nanowires and nanorods, due to its simple fabrication process. Controlling the anodizing conditions is important because of their direct influence on the size of AAO template pores; it affects the size of nanostructures that are fabricated in AAO template. In present study, several alumina templates were fabricated by a two-step electrochemical anodization in different conditions, such as the time of first process, its voltage, and electrolyte concentration. The effect of these factors on pore diameters of AAO templates was investigated using scanning electron microscopy (SEM).

Nazemi, Azadeh; Abolfazl, Seyed; Sadjadi, Seyed

2014-12-01

466

Structure analysis of aluminium silicon manganese nitride precipitates formed in grain-oriented electrical steels  

SciTech Connect

We report a detailed structural and chemical characterisation of aluminium silicon manganese nitrides that act as grain growth inhibitors in industrially processed grain-oriented (GO) electrical steels. The compounds are characterised using energy dispersive X-ray spectrometry (EDX) and energy filtered transmission electron microscopy (EFTEM), while their crystal structures are analysed using X-ray diffraction (XRD) and TEM in electron diffraction (ED), dark-field, high-resolution and automated crystallographic orientation mapping (ACOM) modes. The chemical bonding character is determined using electron energy loss spectroscopy (EELS). Despite the wide variation in composition, all the precipitates exhibit a hexagonal close-packed (h.c.p.) crystal structure and lattice parameters of aluminium nitride. The EDX measurement of ? 900 stoichiometrically different precipitates indicates intermediate structures between pure aluminium nitride and pure silicon manganese nitride, with a constant Si/Mn atomic ratio of ? 4. It is demonstrated that aluminium and silicon are interchangeably precipitated with the same local arrangement, while both Mn{sup 2+} and Mn{sup 3+} are incorporated in the h.c.p. silicon nitride interstitial sites. The oxidation of the silicon manganese nitrides most likely originates from the incorporation of oxygen during the decarburisation annealing process, thus creating extended planar defects such as stacking faults and inversion domain boundaries. The chemical composition of the inhibitors may be written as (AlN){sub x}(SiMn{sub 0.25}N{sub y}O{sub z}){sub 1?x} with x ranging from 0 to 1. - Highlights: • We study the structure of (Al,Si,Mn)N inhibitors in grain oriented electrical steels. • Inhibitors have the hexagonal close-packed symmetry with lattice parameters of AlN. • Inhibitors are intermediate structures between pure AlN and (Si,Mn)N with Si/Mn ? 4. • Al and Si share the same local arrangement; Mn is incorporated in both Mn{sup 2+} and Mn{sup 3+}. • Oxygen incorporation is invoked to account for the thermal stability of (Al,Si,Mn)N.

Bernier, Nicolas, E-mail: n.bernier@yahoo.fr [OCAS N.V., ArcelorMittal Global R and D Gent, Pres. J.F. Kennedylaan 3, 9060 Zelzate (Belgium); Xhoffer, Chris [OCAS N.V., ArcelorMittal Global R and D Gent, Pres. J.F. Kennedylaan 3, 9060 Zelzate (Belgium); Van De Putte, Tom, E-mail: tom.vandeputte@arcelormittal.com [OCAS N.V., ArcelorMittal Global R and D Gent, Pres. J.F. Kennedylaan 3, 9060 Zelzate (Belgium); Galceran, Montserrat [Université Libre de Bruxelles, 4MAT (Materials Engineering, Characterization, Synthesis and Recycling), Avenue F.D. Roosevelt 50, 1050 Brussels (Belgium); CIC Energigune, Albert Einstein 48, 01510 Miñano (Álava) (Spain); Godet, Stéphane [Université Libre de Bruxelles, 4MAT (Materials Engineering, Characterization, Synthesis and Recycling), Avenue F.D. Roosevelt 50, 1050 Brussels (Belgium)

2013-12-15

467

Surface and interface analysis of poly-hydroxyethylmethacrylate-coated anodic aluminium oxide membranes  

NASA Astrophysics Data System (ADS)

The surface and interface of poly (2-hydroxyethylmethacrylate) (PHEMA) and anodic aluminium oxide (AAO) membranes were comprehensively investigated using Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy. It was found that 1s??* (Cdbnd O) and 1s??* (Csbnd O) transitions were dominant on the surface of both bulk PHEMA polymer and PHEMA-surface coated AAO (AAO-PHEMA) composite. Findings from NEXAFS, Fourier-Transform Infrared (FTIR) and X-ray Photoelectron Spectroscopy (XPS) analyses suggest the possibility of chemical interaction between carbon from the ester group of polymer and AAO membrane.

Ali, Nurshahidah; Duan, Xiaofei; Jiang, Zhong-Tao; Goh, Bee Min; Lamb, Robert; Tadich, Anton; Poinern, Gérrard Eddy Jai; Fawcett, Derek; Chapman, Peter; Singh, Pritam

2014-01-01

468

TECHNICAL NOTE: Humidity sensor using a mixture of ammonium paratungstate pentahydrate and aluminium sulphate  

NASA Astrophysics Data System (ADS)

This paper describes an attempt to develop a ceramic humidity sensor having an approximately exponential dependency of its AC conductance on relative humidity and having a short response time. Ammonium paratungstate pentahydrate 0964-1726/7/4/018/img7 and aluminium sulphate 0964-1726/7/4/018/img8 mixed in different wt% are used to make thick films. It is found that the AC conductance of the thick film with 40 wt% of ammonium paratungstate pentahydrate shows an almost exponential relationship with relative humidity. SEM and XRD studies are also carried out on the film to look at the nature and constituents of the samples.

Chakraborty, Supratic; Nemoto, Kohtaro; Hara, Kazuhiro; Lai, P. T.

1998-08-01

469

Recovery of phosphorus and aluminium from sewage sludge ash by a new wet chemical elution process (SESAL-Phos-recovery process).  

PubMed

The potential of a new wet chemical process for phosphorus and aluminium recovery from sewage sludge ash by sequential elution with acidic and alkaline solutions has been investigated: SESAL-Phos (sequential elution of sewage sludge ash for aluminium and phosphorus recovery). Its most innovative aspect is an acidic pre-treatment step in which calcium is leached from the sewage sludge ash. Thus the percentage of alkaline soluble aluminium phosphates is increased from 20 to 67%. This aluminium phosphate is then dissolved in alkali. Subsequently, the dissolved phosphorus is precipitated as calcium phosphate with low heavy metal content and recovered from the alkaline solution. Dissolved aluminium is recovered and may be reused as a precipitant in wastewater treatment plants. PMID:22097049

Petzet, S; Peplinski, B; Bodkhe, S Y; Cornel, P

2011-01-01

470

Aluminium-induced DNA damage and adaptive response to genotoxic stress in plant cells are mediated through reactive oxygen intermediates.  

PubMed

Experiments employing growing root cells of Allium cepa were conducted with a view to elucidate the role of reactive oxygen intermediates (ROI) in aluminium (Al)-induced DNA damage, cell death and adaptive response to genotoxic challenge imposed by ethyl methanesulphonate (EMS) or methyl mercuric chloride (MMCl). In a first set of experiments, root cells in planta were treated with Al at high concentrations (200-800 microM) for 3 h without or with pre-treatments of dihydroxybenzene disulphonic acid (Tiron) and dimethylthiourea (DMTU) for 2 h that trap O(2)(.-)and hydrogen peroxide (H(2)O(2)), respectively. At the end of treatments, generation of O(2)(.-) and H(2)O(2), cell death and DNA damage were determined. In a second set of experiments, root cells in planta were conditioned by Al at low concentrations (5 or 10 microM) for 2 h and after a 2 h intertreatment interval challenged by MMCl or EMS for 3 h without or with a pre-treatment of Tiron or DMTU. Conditioning treatments, in addition, included two oxidative agents viz rose bengal and H(2)O(2) for comparison. Following treatments, root cells in planta were allowed to recover in tap water. Genotoxicity and DNA damage were evaluated by micronucleus (MN), chromosome aberration (CA) or spindle aberration (SA) and comet assays at different hours (0-30 h) of recovery. The results demonstrated that whereas Al at high concentrations induced DNA damage and cell death, in low concentrations induced adaptive response conferring genomic protection from genotoxic challenge imposed by MMCl, EMS and Al. Pre-treatments of Tiron and DMTU prevented Al-induced DNA damage, cell death, as well as genotoxic adaptation to MMCl and EMS, significantly. The findings underscored the biphasic (hormetic) mode of action of Al that at high doses induced DNA damage and at low non-toxic doses conferred genomic protection, both of which were mediated through ROI but perhaps involving different networks. PMID:19955331

Murali Achary, V Mohan; Panda, Brahma B

2010-03-01

471

The effect of broadleaf woodland on aluminium speciation in stream water in an acid-sensitive area in the UK.  

PubMed

Acidification can result in the mobilisation and release of toxic inorganic monomeric aluminium (Al) species from soils into aquatic ecosystems. Although it is well-established that conifer trees enhance acidic atmospheric deposition and exacerbate soil and water acidification, the effect of broad-leaved woodland on soil and water acidification is less clear. This study investigated the effect of broadleaf woodland cover on the acid-base chemistry and Al species present in stream water, and processes controlling these in the acid-sensitive area around Loch Katrine, in the central Highlands, Scotland, UK, where broadleaf woodland expansion is occurring. A nested sampling approach was used to identify 22 stream sampling locations, in sub-catchments of 3.2-61 ha area and 0-45% broadleaf woodland cover. In addition, soils sampled from 68 locations were analysed to assess the influence of: (i) broadleaf woodland cover on soil characteristics and (ii) soil characteristics on stream water chemistry. Stream water pH was negatively correlated with sub-catchment % woodland cover, indicating that woodland cover is enhancing stream water acidification. Concentrations of all stream water Al species (monomeric total, organic and inorganic) were positively correlated with % woodland cover, although not significantly, but were below levels that are toxic to fish. Soil depth, O horizon depth and soil chemistry, particularly of the A horizon, appeared to be the dominant controls on stream water chemistry rather than woodland cover. There were significant differences in soil acid-base chemistry, with significantly lower O horizon pH and A horizon base saturation and higher A horizon exchangeable Al in the wooded catchments compared to the control. This is evidence that the mobile anion effect is already occurring in the study catchments and suggests that stream water acidification arising from broadleaf woodland expansion could occur, especially where tree density is high and acid deposition is predominantly in dry or occult forms. PMID:23085669

Ryan, Jennifer L; Lynam, Philippa; Heal, Kate V; Palmer, Sheila M

2012-11-15

472

The importance of holes in aluminium tris-8-hydroxyquinoline (Alq3) devices with Fe and NiFe contacts  

NASA Astrophysics Data System (ADS)

To study the dominant charge carrier polarity in aluminium tris-8-hydroxyquinoline (Alq3) based spin valves, single Alq3 layer devices with NiFe, ITO, Fe, and aluminium electrodes were fabricated and characterised by Time of Flight (ToF) and Dark Injection (DI) techniques, yielding a lower hole mobility compared to electron mobility. We compare the mobility measured by DI for the dominant carrier injected from NiFe and Fe electrodes into Alq3, to that of holes measured by ToF. This comparison leads us to conclude that the dominant charge carriers in Alq3 based spin valves with NiFe or Fe electrodes are holes.

Zhang, Hongtao; Desai, P.; Zhan, Y. Q.; Drew, A. J.; Gillin, W. P.; Kreouzis, T.

2014-01-01

473

Selective C-alkylation of phenol with methanol over catalysts derived from copper-aluminium hydrotalcite-like compounds  

Microsoft Academic Search

Copper aluminium hydrotalcites (CuAl-HT) with a Cu\\/Al atomic ratio of 2, 3 and 4 (CuAl 2.0-HT, CuAl 3.0-HT, CuAl 4.0-HT) were synthesised by the coprecipitation method using a mixture of NaOH\\/Na2CO3 as precipitant. The pure crystalline hydrotalcite (HT) phase was detected by X-ray diffraction when the copper-aluminium hydrotalcite was prepared without ageing (CuAl 3.0-WAHT). Vapour phase alkylation of phenol with

S. Velu; C. S. Swamy

1996-01-01

474

Additive manufacturing method of producing  

E-print Network

Additive manufacturing method of producing silver or copper tracks on polyimide film Problem/stripping) using an additive process support by a novel bio- degradable photo-initiator package. technology. Building on previous work by Hoyd- Gigg Ng et al. [1,2], Heriot-Watt has developed an additive film

Painter, Kevin

475

Aluminium recovery from waste incineration bottom ash, and its oxidation level.  

PubMed

The recovery of aluminium (Al) scraps from waste incineration bottom ash is becoming a common practice in waste management. However, during the incineration process, Al in the waste undergoes oxidation processes that reduce its recycling potential. This article investigates the behaviour of Al scraps in the furnace of two selected grate-fired waste-to-energy plants and the amount recoverable from the bottom ash. About 21-23% of the Al fed to the furnace with the residual waste was recovered and potentially recycled from the bottom ash. Out of this amount, 76-87% was found in the bottom ash fraction above 5 mm and thus can be recovered with standard eddy current separation technology. These values depend on the characteristics and the mechanical strength of the Al items in the residual waste. Considering Al packaging materials, about 81% of the Al in cans can be recovered from the bottom ash as an ingot, but this amount decreases to 51% for trays, 27% for a mix of aluminium and poly-laminated foils and 47% for paper-laminated foils. This shows that the recovery of Al from the incineration residues increases proportionally to the thickness of the packaging. PMID:23831779

Biganzoli, Laura; Grosso, Mario

2013-09-01

476

Propolis alleviates aluminium-induced lipid peroxidation and biochemical parameters in male rats.  

PubMed

Aluminium is present in many manufactured foods and medicines and is also added to drinking water during purification purposes. Therefore, the present experiment was undertaken to determine the effectiveness of propolis in alleviating the toxicity of aluminium chloride (AlCl3) on biochemical parameters, antioxidant enzymes and lipid peroxidation of male Wistar Albino rats. Animals were assigned to 1 of 4 groups: control; 34 mg AlCl3/kg bw; 50 mg propolis/kg bw; AlCl3 (34 mg/kg bw) plus propolis (50 mg/kg bw), respectively. Rats were orally administered their respective doses daily for 70 days. The levels of thiobarbituric acid reactive substances (TBARS) was increased, and the activities of glutathione S-transferase, superoxide dismutase, catalase and glutathione peroxidase were decreased in liver, kidney and brain of rats treated with AlCl3. While, TBARS was decreased and the antioxidant enzymes were increased in rats treated with propolis alone. Plasma transaminases, lactate dehydrogenase, glucose, urea, creatinine, bilirubin, total lipid, cholesterol, triglyceride and LDL-c were increased, while total protein, albumin and high HDL-c were decreased due to AlCl3 administration. The presence of propolis with AlCl3 alleviated its toxic effects in rats treated with AlCl3. It can be concluded that propolis has beneficial influences and could be able to antagonize AlCl3 toxicity. PMID:19425229

Newairy, Al-Sayeda A; Salama, Afrah F; Hussien, Hend M; Yousef, Mokhtar I

2009-06-01

477

Aluminium Electrolysis with Fe-Ni-Al2O3 Inert Anodes at 850 °C  

NASA Astrophysics Data System (ADS)

Fe-Ni-Al2O3 cermet materials were prepared, and the electrolysis with these anodes were performed in cryolite-based electrolyte consisted of 44NaF-40AlF3-8NaCl-5CaF2-3Al2O3(wt%) at 850 °C. The purity of produced aluminium is 97-98%, while the calculated anodic corrosion rate is 18.2 mm/a-24.0 mm/a. The EPMA analysis showed that there is an oxide scale consisting of Fe2O3 and FeAl2O4 on the anode working surface. The homeostasis of dissolution and formation of oxide scale makes the thickness of the oxide scale and the cell voltage stable within a certain range. The dissolution of oxide scale results in the presence of FeF3 in the electrolyte. By analysis of the corrosion process, it shows that low temperature, high alumina concentration and low CR electrolysis is preferred for using Fe-Ni-Al2O3 inert anodes for aluminium electrolysis.

Shi, Zhongning; Junli, Junli; Gao, Bingliang; Hu, Xianwei; Wang, Zhaowen

2011-06-01

478

Immunostaining of calmodulin and aluminium in Alzheimer's disease-affected brains.  

PubMed

Previous in vitro studies have shown that Al(3+) binds to calmodulin, inducing alterations in its capability to interact with target proteins, accompanied by loss of immunological recognition by its conformational specific monoclonal antibody CAM1. In spite of the wealth of data of calmodulin action in vitro, little information is available on the possible involvement of this protein in the pathology typical of Alzheimer's disease. In the present study, we investigated calmodulin immunoreactivity in post-mortem human brains affected by Alzheimer's disease, compared with age-matched control brains. Conformational monoclonal antibodies raised against Ca(2+)-calmodulin, namely CAM1 and CAM4, were used in this study for the characterization of calmodulin. Calmodulin immunorecognition by monoclonal antibody CAM1 was found to be lost in cortical tissue sample from brains affected by Alzheimer's disease. This finding leads to the hypothesis of a new, possibly inactive, conformation of the molecule during the disease. On the other hand, CAM4 immunoreactivity was decreased in neurons of brains affected by Alzheimer's disease. Anti-Al(3+) monoclonal antibodies revealed instead more marked aluminium immunoreactivity in the affected brains compared to normal ones. The loss of CAM1 immunoreactivity and the occurrence of large amounts of aluminium suggest an alteration of the active conformation of calmodulin in disease-affected brains. These alterations could be involved in the development of Alzheimer's disease pathology. PMID:11470324

Solomon, B; Koppel, R; Jossiphov, J

2001-05-15

479

Sorption of hydrophilic dyes on anodic aluminium oxide films and application to pH sensing.  

PubMed

The sorption of selected hydrophilic pH-sensitive dyes (bromophenol blue, bromothymol blue, bromocresol purple, alizarin red, methyl orange, congo red, rhodamine 6G) on films of anodized aluminium oxide (AAO) was investigated in this study. Depth and pore structure of the AAO channels were adjusted by changing electrolysis time and current density during treatment of aluminium foil in oxalic acid, sulfosalycilic acid and sulfuric acid at concentration levels between 0.2 and 0.6 M. The dyes were immobilized on the AAO surface by direct saturation of the films in dye solutions. It was shown by scanning electron microscopy and X-ray spectral analysis that the dyes penetrated into the AAO channels by more than 1.5 ?m, even at static saturation conditions. The anionic dyes linked to the porous AAO surface exhibited differential shifts of the UV absorption bands in their acidic/basic forms. By combining several dyes, the films have an application range between pH = 0.5-9 in aqueous media. The dye-modified AAO film was a simple, portable, inexpensive and reusable pH sensor with very fast response time and clear colour transitions. PMID:25436239

Silina, Yuliya E; Kuchmenko, Tatyana A; Volmer, Dietrich A

2015-01-20

480

Symptoms of the musculoskeletal system and exposure to magnetic fields in an aluminium plant.  

PubMed Central

OBJECTIVE--The study was performed to examine the influence of the exposure to magnetic fields in the potrooms of an electrolysis plant on the occurrence of musculoskeletal symptoms among the employees. The study was performed after much discussion and worry in the aluminium industry about this issue. METHODS--A retrospective cohort study was performed at an aluminium plant. The occurrence of musculoskeletal symptoms registered at health controls performed by the occupational health care unit in 1986 and 1991 was assessed from employees exposed to magnetic fields in the potrooms (n = 342) and from a control group (n = 277). The data were collected before the discussion about the effects of magnetic fields started. The exposure to static magnetic fields was found to be 3-20 mT inside the potrooms. Ripple components (alternating currents (AC fields)) were registered as well. RESULTS--No difference between the exposed and unexposed groups was found for the reported musculoskeletal symptoms in 1986 or in 1991. CONCLUSIONS--There seems to be no relation between work in potrooms with exposure to static magnetic fields and the occurrence of musculoskeletal symptoms. PMID:7663637

Moen, B E; Drabløs, P A; Pedersen, S; Sjøen, M; Thommesen, G

1995-01-01

481

Coenzyme Q10 Abrogated the 28 Days Aluminium Chloride Induced Oxidative Changes in Rat Cerebral Cortex  

PubMed Central

Objective: The present study was designed to elucidate the impact of oral administration of aluminium chloride for 28 days with respect to oxidative stress in the cerebral cortex of female rats. Further, to investigate the potentials of Coenzyme (Co) Q10 (4, 8, and 12 mg/kg, i.p.) in mitigating the detrimental changes. Materials and Methods: Biochemical estimations of cerebral lipid peroxidation (LPO), reduced glutathione (GSH), vitamin E and activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were carried out after 28 days of aluminium chloride (AlCl3) and Co Q10 exposures along with histopathological examination of cerebral cortex of the rats. Results: Subacute exposure to AlCl3(5 mg/kg) led to significant decrease in levels of GSH, vitamin E and activities of SOD, CAT, GPx, and an increase in LPO of cerebral cortex. These aberrations were restored by Co Q10 (12 mg/kg, i.p.). This protection offered was comparable to that of L-deprenyl (1 mg/kg, i.p.) which served as a reference standard. Histopathological evaluations confirmed that the normal cerebral morphology was maintained by Co Q10. Conclusion: Thus, AlCl3 exposure hampers the activities of various antioxidant enzymes and induces oxidative stress in cerebral cortex of female Wistar rats. Supplementation with intraperitoneal Co Q10 abrogated these deleterious effects of AlCl3. PMID:25253934

Majumdar, Anuradha S.; Nirwane, Abhijit; Kamble, Rahul

2014-01-01

482

Pulmonary disease from exposure to an artificial aluminium silicate: further observations.  

PubMed Central

A cross sectional analysis of the relation between exposure to an artificial aluminium silicate (alunite residue) and pulmonary function changes has been made in 32 subjects, 17 of whom had been previously reported and in whom there was suggestive evidence of a dose response relation between gas transfer and total silicate exposure. Longitudinal data were also available for nine subjects. No dose effect relation was observed in either analysis and only one of the three subjects previously observed to have an abnormal chest radiograph (the index subject) had deteriorated appreciably. Respirable particles of alunite residue were injected intratracheally into Syrian hamsters. No evidence of pulmonary toxicity was seen as judged by bronchoalveolar lavage measurements of the concentrations lactic dehydrogenase, albumin, and the lambda fraction of gold, and the numbers of macrophages, polymorphonuclear cells, and red blood cells (alpha-quartz and ferrous oxide were used as positive and negative controls). These results do not support a significant toxic effect of this aluminium silicate on the lungs. PMID:3259893

Musk, A W; Beck, B D; Greville, H W; Brain, J D; Bohannon, D E

1988-01-01

483

Grain Boundary Sliding in Ultra-fine Grained 5083 Aluminium Alloy  

NASA Astrophysics Data System (ADS)

Quantitative measurement and analysis of grain boundary sliding in Ultra-fine grained 5083 Aluminium by AFM was conducted at 623K. The grain size of as received cryomilled Ultra-fine Grained Aluminium was characterized by AFM and TEM, and the average was founded to be about 300nm. Ion beam polishing / etching technology was used to reveal grain boundaries for AFM characterization. The vertical offset of grain boundary sliding was measured by comparing pre-defoemation and post-deformation AFM images. By analyzing these measurements, the contribution of grain boundary sliding to the total strain was estimated as 22% - 52% at a strain rate of 10 -4 /sec -5x10-2/sec. It was demonstrated that the relatively low value of the contribution of grain boundary sliding to the total strain is most likely the result of testing under experimental condition that favor the dominance of region I ( low stress) of the sigmoidal behavior characterizing high strain rate superplasticity, which was previously reported.

Sung, Ming-Je

484

A domain partitioning based pre-processor for multi-scale modelling of cast aluminium alloys  

NASA Astrophysics Data System (ADS)

In this paper, a microstructural morphology based domain partitioning MDP methodology is developed for materials with non-uniform heterogeneous microstructure. The comprehensive set of methods is intended to provide a concurrent multi-scale analysis model with an initial computational domain that delineates regions of statistical homogeneity and inhomogeneity. The MDP methodology is intended to be a pre-processor to multi-scale analysis of mechanical behaviour and damage of heterogeneous materials, e.g. cast aluminium alloys. It introduces a systematic three-step process that is based on geometric features of morphology. The first step simulates high resolution microstructural information from low resolution micrographs of the material and a limited number of high resolution optical or scanning electron microscopy micrographs. The second step is quantitative characterization of the high resolution images to create effective metrics that can relate microstructural descriptors to material behaviour. The third step invokes a partitioning method to demarcate regions belonging to different length scales in a concurrent multi-scale model. Partitioning criteria for domain partitioning are defined in terms of microstructural descriptors and their functions. The effectiveness of these metrics in differentiating microstructures of a 319-type cast aluminium alloy with different secondary dendrite arm spacings SDAS is demonstrated. The MDP method establishes intrinsic material length scales for the different SDAS, namely, 23, 70 and 100 µm, and consequently subdivides the computational domain for concurrently coupling macro- and micromechanical analyses in the multi-scale model.

Ghosh, Somnath; Valiveti, D. M.; Harris, Stephen J.; Boileau, James

2006-12-01

485

Influence of the green tea leaf extract on neurotoxicity of aluminium chloride in rats.  

PubMed

Aluminium may have an important role in the aetiology/pathogenesis/precipitation of Alzheimer's disease. Because green tea (Camellia sinensis L.) reportedly has health-promoting effects in the central nervous system, we evaluated the effects of green tea leaf extract (GTLE) on aluminium chloride (AlCl3 ) neurotoxicity in rats. All solutions were injected into the cornu ammonis region 1 hippocampal region. We measured the performance of active avoidance (AA) tasks, various enzyme activities and total glutathione content (TGC) in the forebrain cortex (FbC), striatum, basal forebrain (BFb), hippocampus, brain stem and cerebellum. AlCl3 markedly reduced AA performance and activities of cytochrome c oxidase (COX) and acetylcholinesterase (AChE) in all regions. It decreased TGC in the FbC, striatum, BFb, hippocampus, brain stem and cerebellum, and increased superoxide dismutase activity in the FbC, cerebellum and BFb. GTLE pretreatment completely reversed the damaging effects of AlCl3 on AA and superoxide dismutase activity, markedly corrected COX and AChE activities, and moderately improved TGC. GTLE alone increased COX and AChE activities in almost all regions. GTLE reduces AlCl3 neurotoxicity probably via antioxidative effects and improves mitochondrial and cholinergic synaptic functions through the actions of (-)-epigallocatechin gallate and (-)-epicatechin, compounds most abundantly found in GTLE. Our results suggest that green tea might be beneficial in Alzheimer's disease. PMID:23494944

Jelenkovi?, Ankica; Jovanovi?, Marina D; Stevanovi?, Ivana; Petronijevi?, Nataša; Bokonji?, Dubravko; Zivkovi?, Jelena; Igi?, Rajko

2014-01-01

486

Different Cold Spray Deposition Strategies: Single- and Multi-layers to Repair Aluminium Alloy Components  

NASA Astrophysics Data System (ADS)

Cold spraying is increasingly being used for reconstruction or repair of damaged aluminium alloy components, especially in the aviation industry. Both thin (<0.5 mm) and thick (up to 1 cm) coatings are necessary to achieve dimensional recovery of such components. Thin and above all thick coatings can be deposited in a single pass (single layer) or in several passes (multi-pass), resulting in different thermal and stress effects in the component and the coating itself. The thermal input, the amount and type of residual stresses and the porosity affect various characteristics such as adhesion, crack propagation and mechanical properties of the coating. In this study, two sets (single- and multi-pass) of aluminium alloy (AA6061) coatings with different thicknesses (0.5 mm to 2 mm) were deposited onto AA6061 substrates and compared using metallographic and fractographic analyses, four-point bending testing, residual stress analysis and Vickers microhardness indentation. Finally, the coating adhesion and cohesion were measured using the standard ASTM-C633 adhesion test and tubular coating tensile test. This study demonstrates that the single-layer strategy results in greater adhesion and lower porosity, while multilayer coatings have higher elastic modulus. Independent of the strategy, the compressive residual stress decreases as a function of coating thickness.

Rech, Silvano; Trentin, Andrea; Vezzù, Simone; Vedelago, Enrico; Legoux, Jean-Gabriel; Irissou, Eric

2014-12-01

487

Effect of the nature of grain boundary regions on cavitation of a superplastically deformed aluminium alloy  

SciTech Connect

Superplastic deformation of aluminium alloys induces cavity formation throughout the material, so that superplastic forming usually requires to be carried out under superimposed gas pressure to minimize strain-induced damage. This paper deals with the beneficial effects of heat treatment at high temperature for several hours before deformation on cavitation behavior of a superplastically deformed 7475 alloy. Transmission electron microscopy observations show that several microstructural transformations are induced by superplastic deformation and affected by the heat treatment. At first, the generation of dispersoid free zones at the periphery of the grains is observed, the composition of which depends on the prior history of the specimen. Secondly, the formation of long thin fibers extending in the cavities in the as received specimens, these fibers being no longer present in the heat-treated conditions. A TEM characterization of the fibers is presented and a mechanism of their formation is discussed. Such a reduction of the cavitation level for a given strain is interesting in view of superplastic forming of aluminium alloys under atmospheric pressure.

Blandin, J.J.; Varloteaux, A.; Suery, M. [Inst. National Polytechnique de Grenoble, Saint Martin d`Heres (France)] [Inst. National Polytechnique de Grenoble, Saint Martin d`Heres (France); Hong, B.; L`Esperance, G. [Ecole Polytechnique de Montreal, Quebec (Canada). Centre de Caracterisation Microscopique des Materiaux] [Ecole Polytechnique de Montreal, Quebec (Canada). Centre de Caracterisation Microscopique des Materiaux

1996-06-01

488

Different Cold Spray Deposition Strategies: Single- and Multi-layers to Repair Aluminium Alloy Components  

NASA Astrophysics Data System (ADS)

Cold spraying is increasingly being used for reconstruction or repair of damaged aluminium alloy components, especially in the aviation industry. Both thin (<0.5 mm) and thick (up to 1 cm) coatings are necessary to achieve dimensional recovery of such components. Thin and above all thick coatings can be deposited in a single pass (single layer) or in several passes (multi-pass), resulting in different thermal and stress effects in the component and the coating itself. The thermal input, the amount and type of residual stresses and the porosity affect various characteristics such as adhesion, crack propagation and mechanical properties of the coating. In this study, two sets (single- and multi-pass) of aluminium alloy (AA6061) coatings with different thicknesses (0.5 mm to 2 mm) were deposited onto AA6061 substrates and compared using metallographic and fractographic analyses, four-point bending testing, residual stress analysis and Vickers microhardness indentation. Finally, the coating adhesion and cohesion were measured using the standard ASTM-C633 adhesion test and tubular coating tensile test. This study demonstrates that the single-layer strategy results in greater adhesion and lower porosity, while multilayer coatings have higher elastic modulus. Independent of the strategy, the compressive residual stress decreases as a function of coating thickness.

Rech, Silvano; Trentin, Andrea; Vezzù, Simone; Vedelago, Enrico; Legoux, Jean-Gabriel; Irissou, Eric

2014-08-01

489

Addition and Subtraction are Fantastic!  

NSDL National Science Digital Library

This page will help you review your skills with addition and subtraction. Identify a number using base-10 blocks with this activity. Click on the button \\"Show a Problem\\" to begin. Base 10 Blocks Show off your addition skills with base-10 blocks here. Addition with Base-10 Blocks Practice your subtraction skills with base-10 blocks with this activity. Subtraction with Base-10 Blocks ...

Mrs. Keyes

2005-10-27

490

Finite simple additively idempotent semirings  

E-print Network

Since for the classification of finite (congruence-)simple semirings it remains to classify all additively idempotent semirings, we progress on the characterization of finite simple additively idempotent semirings as semirings of join-morphisms of a semilattice. We succeed in doing this for many cases, amongst others for every semiring of this kind with an additively neutral element. As a consequence we complete the classification of finite simple semirings with an additively neutral element. To complete the classification of all finite simple semirings it remains to classify some very specific semirings, which will be discussed here. Our results employ the theory of idempotent irreducible semimodules, which we develop further.

Kendziorra, Andreas

2012-01-01

491

Effects of pre-acclimation to aluminium on the physiology and swimming behaviour of juvenile rainbow trout (Oncorhynchus mykiss) during a pulsed exposure.  

PubMed

Anthropogenic acidification of the freshwater environment causes aluminium to be mobilised into the aquatic environment. When pH falls below 5.5, exposure to aluminium concentrations as low as 12.5 microg.l(-1) can cause serious physiological disturbances in freshwater fish. However, under constant laboratory exposures fish can acclimate and recover physiological status within 5-30 days. In reality, fish in the wild are likely to experience chronic sub-lethal exposure, with occasional elevations (pulses) to much higher levels. The experiment described here investigated the effects of an environmentally realistic, 4-day pulse exposure to a high level of aluminium (36 microg.l(-1)) in two groups of juvenile rainbow trout. One group was exposed to a lower level of aluminium (24 microg.l(-1)) for 16 days before and 10 days after the pulse ('aluminium-acclimated' fish). A second group was exposed to pH 5.2 alone for 16 days before and 10 days after the pulse ('aluminium-naïve' fish). A third group exposed to pH 5.2 alone for 30 days (no aluminium added) acted as controls. Triplicate groups of 24 juvenile rainbow trout (2.3-16.7 g) were randomly allocated to one of these three treatments. Swimming behaviour was monitored throughout and samples were taken on days 14, 20, 22, 26 and 30 for assessment of physiological status. No treatment effects were recorded in the control group (pH 5.2 alone). Fish in the 'aluminium-acclimated' treatment became hypo-active upon initiation of the exposure to 24 microg.l(-1) aluminium, but recovered after just 4 days of this exposure. Subsequent challenge on day 16 with the 36 microg.l(-1) aluminium 'pulse' caused these fish to became hypo-active again, but they recovered normal swimming behaviour whilst still subject to the 4-day pulse. The 'aluminium-naïve' fish also became hypo-active during the pulse exposure (36 microg.l(-1) aluminium). However, they did not exhibit any recovery of swimming behaviour, either during the pulse, or even 6 days after the cessation of the pulse, despite a rapid depuration of gill aluminium load (within 2 days of the pulse finishing). Mortality was low in the aluminium-acclimated fish (4%) and significantly higher in the aluminium-naïve fish (26%). Haematological disturbances were most extreme in the aluminium-naïve fish and had not recovered to control levels 6 days after the end of the pulse. This study provides new evidence, using behavioural responses, that previous exposure to low levels of aluminium may be an important factor abating the impact of aluminium on fish in the natural environment. PMID:11064125

Allin, C J; Wilson, R W

2000-12-01

492