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1

[Aluminium content in foods with aluminium-containing food additives].  

PubMed

The aluminium (Al) content of 105 samples, including bakery products made with baking powder, agricultural products and seafoods treated with alum, was investigated. The amounts of Al detected were as follows (limit of quantification: 0.01 mg/g): 0.01-0.37 mg/g in 26 of 57 bakery products, 0.22-0.57 mg/g in 3 of 6 powder mixes, 0.01-0.05 mg/g in all three agricultural products examined, 0.03-0.90 mg/g in 4 of 6 seafood samples, 0.01-0.03 mg/g in 3 of 11 samples of instant noodles, 0.04-0.14 mg/g in 3 of 4 samples of vermicelli, 0.01 mg/g in 1 of 16 soybean products, but none in soybeans. Amounts equivalent to the PTWI of a 16 kg infant were detected in two samples of bakery products, two samples of powder mixes and one sample of salted jellyfish, if each sample was taken once a week. These results suggest that certain foods, depending on the product and the intake, might exceed the PTWI of children, especially infants. PMID:22450671

Ogimoto, Mami; Suzuki, Kumi; Kabashima, Junichiro; Nakazato, Mitsuo; Uematsu, Yoko

2012-01-01

2

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

Microsoft Academic Search

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

Salim M. Saiyed; Robert A. Yokel

2005-01-01

3

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

E-print Network

Gypsum addition to soils contaminated by red mud: Implications for aluminium, arsenic, molybdenum. 4 Department of Applied Biotechnology and Food Science, Budapest University of Technology, contaminated soils, gypsum, toxic trace elements, arsenic, vanadium, aluminium, organic matter leaching, p

Burke, Ian

4

Precipitation of reactive aluminium hydroxide from an acidic aluminium sulphate solution by addition of sodium hydroxide  

Microsoft Academic Search

The goal of the present thesis was to study the possibilities of producing an aluminium hydroxide, which would easily dissolve in hydrochloric ac id. Furthermore, the product should be easy to dewater. In the experiments, which were made batch-wise, a 50% sodium hydroxide was used to accomplish the precipitation. The precipitation of aluminium hydroxide is a dynamic process that depends

Emilia Andersson; Henrik Hansson

5

Microstructure of a pressure die cast magnesium—4wt.% aluminium alloy modified with rare earth additions  

Microsoft Academic Search

Addition of cerium-rich mixtures of rare earth (RE) elements to aluminium-containing magnesium pressure die cast alloys is known to improve the creep properties at elevated temperatures. In the present investigation, a detailed description of the microstructure of a magnesium-4 wt.% aluminium alloy containing 1.4 wt.% of a cerium-rich mixture of RE elements is presented. Particle types occurring and their distribution

G. Pettersen; H. Westengen; R. Høier; O. Lohne

1996-01-01

6

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

PubMed

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 raw materials were low (0.10-451.5 mg/kg). Therefore, aluminium levels in food additives used in these foods was determined and it was found that some food additives contained a high concentration of aluminium (0.005-57.4 g/kg). The results suggested that, in the interest of public health, food additives containing high concentrations of aluminium should be replaced by those containing less. This study has provided new information on aluminium levels in Chinese processed foods, raw materials and a selection of food additives. PMID:24786247

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

2011-01-01

7

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

8

TEM and HRTEM studies of ball milled 6061 aluminium alloy powder with Zr addition.  

PubMed

The effect of mechanical alloying on the microstructure of atomized 6061 aluminium alloy powder and 6061 powder with a zirconium addition was studied in the work. The atomized 6061 aluminium alloy powder and 6061 powder with addition of 2 wt.% Zr were milled in a planetary ball mill and investigated using X-ray diffraction measurements, conventional and high-resolution electron microscopy (TEM/HRTEM) and high-angle annular dark field scanning transmission electron microscopy combined with energy dispersive X-ray microanalysis. An increase of stresses was observed in milled powders after the refinement of crystallites beyond 100 nm. In the powder with zirconium addition, some part of the Zr atoms diffused in aluminium forming a solid solution containing up to 0.5 wt.% Zr. The remaining was found to form Zr-rich particles containing up to 88 wt.% Zr and were identified as face centred cubic (fcc) phase with lattice constant a= 0.48 nm. That fcc phase partially transformed into the L1(2) ordered phase. Eighty-hour milling brought an increase of microhardness (measured with Vickers method) from about 50 HV (168 MPa) for the initial 6061 powder to about 170 HV (552 MPa). The addition of zirconium had no influence on the microhardness. PMID:20500426

Lity?ska-Dobrzy?ska, L; Dutkiewicz, J; Maziarz, W; Rogal, ?

2010-03-01

9

Effect of element additions on wear property of eutectic aluminium-silicon alloys  

Microsoft Academic Search

The effects of cerium, zinc and zirconium additions and subsequent heat treatment on wear of the eutectic aluminium-silicon alloys have been investigated in dry sliding against a steel counterface by using a pin-on-disc machine. Wear surfaces and debris were examined by scanning electron microscopy. Wear characteristics of both binary Al-Si alloys and a commercial LM 13 alloy, were also studied

Mohd Harun; I. A. Talib; A. R. Daud

1996-01-01

10

Neutron activation analysis by standard addition and solvent extraction: Determination of impurities in aluminium.  

PubMed

A separation scheme based on selective extraction in conjunction with the standard addition technique has been developed for the determination of impurities in aluminium by neutron activation. Preliminary investigations have been carried out on the extractability of Sc, Co, Hf, Fe, Sn, Cd, Zn, Ag, Cr, Ce, Cs and Rb by TDA and TBP from acidic media. The best conditions are predicted for the separation of these elements into fractions suitable for analysis by gamma-ray spectrometry. Recovery values of approximately 90% were obtained for all the elements. PMID:18960206

Alian, A; Haggag, A

1967-09-01

11

Influence of exogenous silicon addition on aluminium tolerance in rice seedlings.  

PubMed

For better understanding of silicon (Si)-mediated increase in metal tolerance in plants, the alterations in growth, mineral elements and anatomical features were investigated in rice seedlings exposed to Si (10 ?M) and aluminium (Al; 50 ?M). Al decreased seedling growth which was accompanied by an increase in Al accumulation. In contrast, addition of Si alleviated toxic effects of Al and led to the decrease in Al accumulation. Magnesium (Mg) and zinc (Zn) contents were decreased by Al; however, Si addition prevented decrease in Mg and Zn contents. Manganese (Mn) content was increased by Al while Si addition did not have a significant effect on Mn content under Al treatment. Al exposure decreased frequency of stomata and root hairs, length of root hairs and leaf epidermal cells, and distorted the structure and integrity of mesophyll cells and phloem; however, addition of Si reduced these abnormalities. Results showed that Si addition protected rice seedlings against Al toxicity by decreasing Al accumulation and by maintaining level of some mineral elements, and the key structures of leaf and root. PMID:21681465

Singh, Vijay Pratap; Tripathi, Durgesh Kumar; Kumar, Dharmendra; Chauhan, Devendra Kumar

2011-12-01

12

Calcium and aluminium-based fillers as flame-retardant additives in silicone matrices. I. Blend preparation and thermal properties  

Microsoft Academic Search

This series investigates silicone composites with enhanced thermal behaviour for cable applications. Calcium and aluminium-based fillers introduced into silicone formulations were classified according to three categories: non-hydrated fillers such as CaCO3 (precipitated calcium carbonate and natural calcite) and wollastonite, water-releasing fillers such as calcium hydroxide, ATH, boehmite, and hydroxyl-functionalized fillers including alumina and mica. The fillers were first characterized in

Siska Hamdani; Claire Longuet; José-Marie Lopez-Cuesta; François Ganachaud

2010-01-01

13

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

14

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

15

ADDITION  

NSDL National Science Digital Library

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

Games, Aidan'S M.

2010-12-20

16

ALUMINIUM: ITS TOXICITY, BIOAVAILABILITY AND RETENTION IN THE HUMAN BODY  

Microsoft Academic Search

Aluminium is commonest metal within the earth's crust. Nevertheless, most natural waters, biota and the air contain very low concentrations. It follows that, except in the case of exposure to pharmaceutical preparations, mans exposure to aluminium - mostly in the diet - is very low. In addition, only a very small fraction of ingested aluminium is bioavailable (0.0001 - 0.01)

N. D. PRIEST

17

Further information on aluminium inhalation in silicosis.  

PubMed Central

OBJECTIVES--In previous studies, a significant reduction in biological activity of quartz by the surface chemistry of aluminium was noted. Aluminium lactate inhalation one month after quartz exposure significantly suppressed silicosis. In a recent study, it was noted that aluminium inhalation failed to alter the silicosis process after disease was recognised by standard chest radiography in the first year after monthly treatment. METHODS--That study was extended with the same groups of sheep, the aluminium treated group received weekly aerosol of 100 mg of aluminium lactate for an additional two years. All sheep were evaluated at three-month intervals by chest radiography, lung function, and lung lavage. RESULTS--The sheep with silicosis had significantly reduced lung functions, increased cellularity, phospholipids, and hyaluronan. These changes persisted for several years without significant differences between the silicotic sheep with or without the aluminium aerosol treatment. CONCLUSION--Aluminium aerosol treatment of silicosis after radiographic recognition of disease and the end of exposure did not alter the disease process. PMID:8535501

Begin, R; Masse, S; Dufresne, A

1995-01-01

18

Mullite and alumina composites preparation from cordierite and aluminium hydroxide  

SciTech Connect

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

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

2008-05-06

19

Aluminium doped zinc oxide films: formation process and optical properties  

Microsoft Academic Search

Aluminium doped zinc oxide films were prepared through a non-alcoxide sol–gel and dip-coating technique, from zinc acetate and aluminium nitrate in ethanolic solution. The acetate hydrolysis was promoted by lactic acid. The doping level of aluminium was 0.8 mol%. Acetylacetone and diethanolamine were used as additives to improve film homogeneity. The chemical processes which occur during the drying and oxide

Rodrigo Ferreira Silva; Maria Elisabete Darbello Zaniquelli

1999-01-01

20

Anodizing of aluminium alloys  

Microsoft Academic Search

Anodizing is used widely in the surface treatment of aluminium alloys for aerospace applications. Considers recent advances in understanding of the influences of alloying elements in anodizing of aluminium alloys and, in particular, their applicability to second phase particles during anodizing of commercial alloys. Through more precise knowledge of the response of second phase materials to anodic polarization, improved anodizing

G. E. Thompson; H. Habazaki; K. Shimizu; M. Sakairi; P. Skeldon; X. Zhou; G. C. Wood

1999-01-01

21

Aluminium precipitates in the primary silicon of as-sprayformed hypereutectic aluminium-silicon alloys  

Microsoft Academic Search

Precipitates have been observed in the primary silicon of as-spray-formed hypereutectic aluminium-silicon alloys with and without various alloy additions. The precipitates have been investigated using transmission electron microscopy and high-resolution transmission electron microscopy. They are aluminium based and generally adopt a spheroidal morphology, with diameters in the range of approximately 5-10nm, unless located on a stacking fault or grain boundary.

C. J. D. Hetherington; H. V. Atkinson

2000-01-01

22

The structures of fully eutectic aluminium-silicon alloy castings  

Microsoft Academic Search

Strontium-modified aluminium alloys containing 14 to 15 wt% silicon were cast with fully eutectic structures by using heated moulds and high-purity materials. In alloys containing the additional elements magnesium, copper or nickel, a distinct eutectic colony structure was evident outlined by intermetallic compounds. At the edges of the castings the eutectic colony structures and the aluminium grains (revealed by anodizing)

T. B. Abbott; B. A. Parker

1990-01-01

23

Compartmental model for aluminium biokinetics  

Microsoft Academic Search

An open compartmental model for describing aluminium biokinetics is presented with a central compartment consisting of transferrinand citrate-bound aluminium in blood plasma and interstitial fluid, and three peripheral compartments for organs, muscles and bones and the gastro-intestinal tract. The rate constants describing the transport of aluminium are normalized to an estimated plasma volume and do not depend on the size

E. Nolte; E. Beck; C. Winklhofer; C. Steinhausen

2001-01-01

24

Aluminium and human breast diseases  

Microsoft Academic Search

The human breast is exposed to aluminium from many sources including diet and personal care products, but dermal application of aluminium-based antiperspirant salts provides a local long-term source of exposure. Recent measurements have shown that aluminium is present in both tissue and fat of the human breast but at levels which vary both between breasts and between tissue samples from

P. D. Darbre; D. Pugazhendhi; F. Mannello

25

Electroplated bright aluminium coatings for anticorrosion and decorative purposes  

Microsoft Academic Search

This paper is dedicated to the study of electrodeposited aluminium layers as anticorrosion protective coatings on metallic substrates. The aim of this approach is to propose a non-toxic alternative to the traditional nickel–chromium coating, for anticorrosive and decorative purposes. Aluminium was electrodeposited on carbon steel substrates from chloroaluminate based ionic liquids with and without the addition of 1,10-phenantroline. In the

Licia Barchi; Ugo Bardi; Stefano Caporali; Mauro Fantini; Alessandro Scrivani; Andrea Scrivani

2010-01-01

26

The effect of iron and aluminium for phosphorus removal on anaerobic digestion and organic sulfur generation.  

PubMed

The addition of iron or aluminium into activated sludge basins for phosphorus removal is likely to impact both the efficiency of the anaerobic digestion process and the generation of odor-causing compounds following digestion and dewatering. In this study, the impact of iron and aluminium addition on digestion and odor-causing compounds was investigated by using batch digestion of combined primary and waste activated sludge. It was found that aluminium addition resulted in a decrease in volatile solids destruction by anaerobic digestion of approximately 2%. Of the 7 sludges tested, 5 showed a small increase in volatile solids destruction after iron addition. With regard to the generation of organic sulfur odors from the dewatered sludge cakes, both iron and aluminium reduced odor-causing gases except for one sludge that had already received iron for phosphorus control in the full-scale process. It appears that iron and aluminium addition will benefit odor control. PMID:20651448

Novak, John T; Park, Chang Min

2010-01-01

27

Direct electrodeposition of aluminium nano-rods  

Microsoft Academic Search

Electrodeposition of aluminium within an alumina nano-structured template, for use as high surface area current collectors in Li-ion microbatteries, was investigated. The aluminium electrodeposition was carried out in the ionic liquid 1-ethyl-3-methylimidazolium chloride:aluminium chloride (1:2 ratio). First the aluminium electrodeposition process was confirmed by combined cyclic voltammetry and electrochemical quartz crystal microbalance measurements. Then, aluminium was electrodeposited under pulsed-potential conditions

Emilie Perre; Leif Nyholm; Torbjörn Gustafsson; Pierre-Louis Taberna; Patrice Simon; Kristina Edström

2008-01-01

28

Recycling of aluminium swarf by direct incorporation in aluminium melts  

Microsoft Academic Search

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

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

2009-01-01

29

Comparison of the x-ray attenuation properties of breast calcifications, aluminium, hydroxyapatite and calcium oxalate  

NASA Astrophysics Data System (ADS)

Aluminium is often used as a substitute material for calcifications in phantom measurements in mammography. Additionally, calcium oxalate, hydroxyapatite and aluminium are used in simulation studies. This assumes that these materials have similar attenuation properties to calcification, and this assumption is examined in this work. Sliced mastectomy samples containing calcification were imaged at ×5 magnification using a digital specimen cabinet. Images of the individual calcifications were extracted, and the diameter and contrast of each calculated. The thicknesses of aluminium required to achieve the same contrast as each calcification when imaged under the same conditions were calculated using measurements of the contrast of aluminium foils. As hydroxyapatite and calcium oxalate are also used to simulate calcifications, the equivalent aluminium thicknesses of these materials were also calculated using tabulated attenuation coefficients. On average the equivalent aluminium thickness was 0.85 times the calcification diameter. For calcium oxalate and hydroxyapatite, the equivalent aluminium thicknesses were 1.01 and 2.19 times the thickness of these materials respectively. Aluminium and calcium oxalate are suitable substitute materials for calcifications. Hydroxyapatite is much more attenuating than the calcifications and aluminium. Using solid hydroxyapatite as a substitute for calcification of the same size would lead to excessive contrast in the mammographic image.

Warren, L. M.; Mackenzie, A.; Dance, D. R.; Young, K. C.

2013-04-01

30

Aluminium levels in Italian diets and in selected foods from aluminium utensils  

Microsoft Academic Search

In Italy, data on aluminium concentration in food items are scarce although aluminium containers are widely used to cook, to freeze or to wrap foods (foil) and it is known that aluminium can migrate from containers to foods. Therefore, an experimental study was carried out to quantify aluminium exposure from ingestion of actual total diets and from migration from containers

L. Gramiccioni; G. Ingrao; M. R. Milana; P. Santaroni; G. Tomassi

1996-01-01

31

Complexometric determination of aluminium, zirconium, and hafnium  

Microsoft Academic Search

Methods for the complexometric titration of aluminium, zirconium and hafnium are described using pyrocatechol violet as indicator. The EDTA titration of zirconium and hafnium is performed in acid medium and that of aluminium in a solution buffered with acetate.

I. Hazan; F. Feik; J. Korkisch

1965-01-01

32

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

33

Review article Aluminium toxicity in declining forests  

E-print Network

toxicity I aluminium speciation I acid rain I forest decline Résumé — La toxicité de l'aluminium dans to such chemi- cal environments. Due to atmospheric pol- lution and related acid deposition, how- ever, Al aluminique / spéciation de l'aluminium / pluies acides / dépérissement forestier #12;INTRODUCTION Two

Boyer, Edmond

34

Synthesis of aluminium complexes bearing a piperazine-based ligand system  

Microsoft Academic Search

Aluminium complexes bearing the N,N-chelating ligand 1,4-bis(2-hydroxy-3,5-di-tert-butyl)piperazine (1) have been synthesised. Both monometallic and bimetallic aluminium methyl complexes (2 and 3, respectively) were prepared by treatment of 1 with the appropriate amount of AlMe3. Complex 2 can be converted to 3 by addition of excess AlMe3. Bimetallic aluminium-ethyl complex 4 was also prepared. Treatment of 1 with AlEt2Cl afforded the

Nick C. Johnstone; Elham S. Aazam; Peter B. Hitchcock; J. Robin Fulton

2010-01-01

35

The influence of corrosion on the erosion of aluminium by aqueous silica slurries  

Microsoft Academic Search

The slurry erosion-corrosion behaviour of aluminium in aqueous silica slurries containing 0.5 M NaCl, acetic acid and 0.1 M Na2CO3 at open circuit has been investigated using a modified slurry erosion rig. The erosion rates of aluminium in the NaCl and acetic acid slurries were much higher than those in an aqueous slurry without electrolyte additives even though the pure

Y. Li; G. T. Burstein; I. M. Hutchings

1995-01-01

36

Strength, deformation, fracture behaviour and ductility of aluminium-lithium alloys  

Microsoft Academic Search

The ever increasing need for high strength, improved performance, lightweight and cost-effective materials has resulted in significant improvements and development of new aluminium alloys for structural applications. Lithium additions to aluminium have the potential for providing a class of high strength alloys with exceptional properties suitable for weight-critical applications. In this paper, published studies of composition-processing-microstructure relationships are discussed. Contributions

E. J. Lavernia; T. S. Srivatsan; F. A. Mohamed

1990-01-01

37

Aluminium electrodeposition under ambient conditions.  

PubMed

The electrodeposition of aluminium is demonstrated using a eutectic mixture of aluminium chloride and urea. The mixture is shown to be conducting through the formation of both cationic ([AlCl2·urean](+)) and anionic (AlCl4(-)) species and electrodeposition is achieved through the cationic species. The use of a biphasic system with the ionic liquid and a protective hydrocarbon layer allows metal deposition to be carried out in an environment with ambient moisture without the need for a glove box. A direct comparison is made between the AlCl3:urea and imidazolium chloride:AlCl3 systems and the differences in speciation and mass transport manifest themselves in different deposit morphologies. Brighteners which work in the chloroaluminate system such as toluene and LiCl are shown to be ineffective in the urea based system and the reasons for these differences are ascribed to the mechanism of the anodic reaction which is rate limiting. PMID:24916113

Abbott, Andrew P; Harris, Robert C; Hsieh, Yi-Ting; Ryder, Karl S; Sun, I-Wen

2014-07-28

38

Recycling und Werkstoffentwicklung von Aluminium  

Microsoft Academic Search

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

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

2011-01-01

39

Tungstate-modified aluminium phosphate  

Microsoft Academic Search

A series of tungstate-impregnated aluminium phosphate samples are prepared by varying the tungstate weight percent from 3 to 20 and characterised by XRD and N2-adsorption–desorption method. Surface areas are found to decrease with increase in tungstate loading. However, tungstate-loaded samples exhibit an increasing trend in acidity and catalytic activity. The sample with 10 wt.% tungstate loading shows highest dehydration and

K. M Parida; M Acharya; T Mishra

2000-01-01

40

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

NASA Astrophysics Data System (ADS)

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

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

2013-04-01

41

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

42

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

43

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

44

Aluminium in an ocean general circulation model  

E-print Network

Hulten: Aluminium in an ocean general circulation model 3 #12;Model overview physics NEMO-OPA (prescribed;Forcing: currents Figure: Velocity (m/s) at ocean surface, average of an OPA climatology Marco van Hulten Streamfunction (Sv), average of an OPA climatology Marco van Hulten: Aluminium in an ocean general circulation

Haak, Hein

45

Feasibility of warm drawing of aluminium products  

Microsoft Academic Search

A study is carried out on the feasibility of using warm forming at temperatures from 100 to 250°C in order to improve the makeability of aluminium sheet components. Drawing tests are performed on 1050, 5754 and 6016 series aluminium sheets. Both box shaped and conical rectangular products are made with a tool with heated die and blankholder. The effect of

P. J Bolt; N. A. P. M Lamboo; P. J. C. M Rozier

2001-01-01

46

Aluminium solubility in rainwater and molten snow  

Microsoft Academic Search

Large variations of aluminium solubilities are found in marine and rural precipitations. The results of seven field experiments are used to produce a model of the solubilization of aluminium independent of the sampling site. Large variations of solubility appear, and the pH seems to be a major factor explaining this solubility changes. Thermodynamic calculations at T=278K suggest that, at higher

R. Losno; J. L. Colin; N. Bris; G. Bergametti; T. Jickells; B. Lim

1993-01-01

47

Production of ?-alumina from waste aluminium dross  

Microsoft Academic Search

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

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

2007-01-01

48

Aluminium compounds for use in vaccines  

Microsoft Academic Search

Aluminium adjuvants are the most widely used adjuvants in both human and veterinary vaccines. These adjuvants have been used in practical vaccination for more than 60 years and are generally recognized as safe and as stimulators of Th2 immunity. The present review gives a short introduction to the pioneering research at the start of the use of aluminium compounds as

Erik B Lindblad

2004-01-01

49

Development of multilayer coatings for forming dies and tools of aluminium alloy from liquid state  

NASA Astrophysics Data System (ADS)

In this work, a nanocomposite (Cr,Al)xN1-x/Si3N4 coating system was deposited on H11 hot work tool steel, using the Lateral Arc Rotating Cathodes (LARC®) deposition system and modulating the chemical composition of the chromium and aluminium-silicon content. Structural characterizations were performed using scanning electron microscopy, equipped with energy dispersive spectroscopy probe, and applying x-ray diffraction, for the evaluation of phase constitution and crystallite size. In addition to the structural features, the coatings' resistance to cyclic immersions in molten aluminium alloy was evaluated. The deposited CrAlSiN coatings exhibited an fcc-Cr1-xAlxN type structure with different aluminium contents, which directly influence hardness and wear and fatigue resistance in cyclic immersion tests. The main failure modes that occurred on the coatings' surface were soldering and thermal fatigue cracks mainly in the form of heat checks. The aluminium rich coatings were able to withstand about 15 000 cycles, whereas the decrease in the aluminium content in the coatings results in a decrease in the resistance to the immersion in molten aluminium bath. It is worthwhile to note that uncoated H11, subjected to similar testing conditions, withstood at maximum 5000 cycles.

Torres, E.; Ugues, D.; Brytan, Z.; Perucca, M.

2009-05-01

50

Acid dissolution of alumina from waste aluminium dross  

Microsoft Academic Search

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

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

2008-01-01

51

Electron microscope investigations on the morphology of aluminium hydroxides  

Microsoft Academic Search

Summary  The results are given of an investigation by means of the electron microscope and electron diffraction of the morphology of\\u000a amorphous aluminium hydroxide and boehmite.\\u000a \\u000a The ageing process of amorphous aluminium hydroxide prepared from aluminium nitrate, ammonium alum and amalgamated aluminium\\u000a was studied.

L. Moscou; G. S. van der Vlies

1959-01-01

52

Investigation of the aluminium-aluminium oxide reversible transformation as observed by hot stage electron microscopy.  

NASA Technical Reports Server (NTRS)

Thin foils of high purity aluminium and an Al-Al2O3 SAP type of alloy were oxidised in a specially designed hot stage specimen chamber in an electron microscope. Below 450 C, amorphous aluminium oxide formed on the foil surface and was first detectable at foil edges, holes, and pits. Islands of aluminium then nucleated in this amorphous oxide. The aluminium islands displayed either a lateral growth with eventual coalescence with other islands, or a reoxidation process which caused the islands to disappear. The aluminium island formation was determined to be related to the presence of the electron beam. A mechanism based upon electron charging due to the electron beam was proposed to explain the nucleation, growth, coalescence, disappearance, and geometry of the aluminium islands.

Grove, C. A.; Judd, G.; Ansell, G. S.

1972-01-01

53

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

54

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

55

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

56

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

57

Standardization and validation of a new atomic absorption spectroscopy technique for determination and quantitation of Aluminium adjuvant in immunobiologicals  

Microsoft Academic Search

In the present study, Aluminium quantification in immunobiologicals has been described using atomic absorption spectroscopy (AAS) technique. The assay was found to be linear in 25–125?g\\/ml Aluminium range. The procedure was found to be accurate for different vaccines with recoveries of external additions ranging between 93.26 and 103.41%. The mean Limit of Variation (L.V.) for both intra- and inter-assay precision

Arti Mishra; Sumir Rai Bhalla; Sameera Rawat; Vivek Bansal; Rakesh Sehgal; Sunil Kumar

2007-01-01

58

Microstructure and superplasticity in a stir-cast SiCp/2024 aluminium composite  

SciTech Connect

Aluminium matrix composites reinforced with ceramic whiskers or particles have a high specific strength and modulus in addition to good wear resistance and heat resistance. They have shown considerable promise in structural applications, but one of the main drawbacks of the composite is the ductility, which leads to the poor formability, and thus limits their applications. Superplastic forming is a viable technique that is used to solve this problem. A number of aluminium base composites can exhibit superplasticity. Until now, almost all of the composites in superplastic studies were prepared by the powder metallurgy (PM) method. This method causes the composites to have very fine grains (about 1 [mu]m) and fewer microstructural defects; as a result, they exhibited high strain rate superplasticity. Studies on the superplasticity in ingot metallurgy (IM) aluminium matrix composites are rare, but are equally important. Because IM is a low cost method of preparing aluminium matrix composites, it will play an increasingly more important role in the future applications of the composites. In this work the authors investigated the microstructure and superplasticity of a IM 2024 aluminium matrix composite, reinforced with silicon carbide particles (SiCp/2024). They thermomechanically treated the composite by hot forging and extrusion, obtained a superplastic elongation of 685% at an initial strain rate of 5 [times] 10[sup [minus]4]s[sup [minus]1], with a 788K temperature. They also observed and analyzed the microstructure of this composite.

Wei Zheng; Zhang Baoliang; Wang Yanwen (Beijing Research Inst. of Mechanical and Electrical Technology (China))

1994-06-01

59

Morphology of nanometric size particulate aluminium-doped zinc oxide films  

Microsoft Academic Search

Aluminium-doped zinc oxide films were prepared through an alcoholic sol–gel route using Zn(CH3COO)2?·?2H2O as non-alcoxide precursor. Al(NO3)3?·?9H2O was used as dopant with an aluminium to zinc ratio of 5% (mol). Lactic acid was used as the hydrolysis promoter. Acetylacetone and diethanolamine were used as additives to improve film homogeneity. The dip-coating process was used for the sol transfer. The chemical

Rodrigo F Silva; Maria E. D Zaniquelli

2002-01-01

60

Growth of eutectic silicon from primary silicon crystals in aluminium-silicon alloys  

Microsoft Academic Search

Technological interest in aluminium-silicon alloys derives, fundamentally, from their excellent moulding properties provided by the presence of silicon. In addition, they possess high thermal and electrical conductivities and good corrosion resistance. The possibility of modification of their cast structure by adding small quantities of alkaline and alkaline-earth elements makes their mechanical characteristics very competitive. Metallographic observations of the structures of

A. J. Criado; J. A. Martínez; R. Calabrés

1997-01-01

61

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

Microsoft Academic Search

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

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

1995-01-01

62

A novel technique for the deposition of aluminium-doped zinc oxide films  

Microsoft Academic Search

Aluminium-doped zinc oxide is used in many applications as a transparent conductive oxide coating. Such coatings are often deposited by DC reactive sputtering of metallic targets, or RF sputtering of ceramic targets. Both of these techniques have their limitations. In the DC case, alloy targets are expensive and only allow a single composition per target. Additionally, in the RF case,

P. J. Kelly; Y. Zhou; A. Postill

2003-01-01

63

Electrical Conductivity of Solutions of Aluminium (III), Gallium (III) and Indium (III) Iodides in Alkyl Iodides  

Microsoft Academic Search

SEVERAL investigations have been devoted to the electrical conductivity of aluminium halides in alkyl halide solutions1-5. The conductance of these solutions has been attributed to the formation of some complexes or addition compounds composed of both interacting molecules. No investigations on analogous systems with gallium and indium halides have hitherto been performed. In order to gain more information of the

A. Halpern; A. POLACZEK

1963-01-01

64

Effect of aluminium phosphate as admixture on oxychloride cement  

Microsoft Academic Search

The effect of admixing of aluminium phosphate on oxychloride cement in the matrix has been investigated. It is shown that\\u000a aluminium phosphate retards the setting process of the cement and improves water-tightness.

M. P. S. Chandrawat; R. N. Yadav

2000-01-01

65

Aluminium assay and evaluation of the local reaction at several time points after intramuscular administration of aluminium containing vaccines in the Cynomolgus monkey  

Microsoft Academic Search

Aluminium hydroxide and aluminium phosphate have been widely used as vaccine adjuvants with a good safety record for several decades. The recent observation in human deltoid muscle of macrophage aggregates containing aluminium hydroxide spicules and termed Macrophagic Myofasciitis (MMF) has encouraged research on aluminium salts. This study was conducted in order to further investigate the clearance of aluminium at the

François Verdier; Roger Burnett; Claire Michelet-Habchi; Philippe Moretto; Françoise Fievet-Groyne; Elisabeth Sauzeat

2005-01-01

66

addition 245 Addition sur  

E-print Network

;addition 253 Générateur VHDL : ADD_SUB paramétrable library IEEE; use IEEE.std_logic_1164.all, IEEE.std_logic_components.all; entity ADD_SUB is generic ( N : positive := 6); port ( A, B : in std_logic_vector(N-1 downto 0); AS_IN : in std_logic; AS_OUT : out std_logic; S : out std_logic_vector(N-1 downto 0)); end ADD_SUB; architecture

Paris-Sud XI, Université de

67

The Microstructure of Mechanically Alloyed Nanocrystalline Aluminium-Magnesium  

E-print Network

The Microstructure of Mechanically Alloyed Nanocrystalline Aluminium-Magnesium Jen Gubicza1 analysis. Magnesium gradually goes into solid solution during ball milling and after 3 h almost all. Experimental A series of aluminium-magnesium samples were prepared from high purity aluminium (99.9%) powder

Gubicza, Jenõ

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

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

Microsoft Academic Search

The paper concerns aluminium hydroxides precipitated during hydrolysis of aluminium acetate in ammonia medium, as well as\\u000a aluminium oxides obtained through their calcination at 550, 900 or 1200?C for 2 h. The following techniques were used for\\u000a analysing of obtained materials: thermal analysis, IR spectroscopy, X-ray diffraction, low-temperature nitrogen adsorption,\\u000a adsorption-desorption of benzene vapours and scanning electron microscopy.\\u000a \\u000a Freshly precipitated

Barbara Pacewska; Olga Kluk-P?osko?ska; Dariusz Szychowski

2007-01-01

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

PubMed

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

Mannello, F; Ligi, D; Canale, M

2013-11-01

72

High strain rate superplasticity of AlN particulate reinforced aluminium alloy composites  

SciTech Connect

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 whisker or particulate reinforced aluminium alloy composites is due to the low tensile ductility, fracture toughness at room temperature and, also, their hardness qualities that make it difficult to deform by conventional forming processing and machining by ordinary tools. It has been found, however, that aluminium alloy composites reinforced by SiC or Si[sub 3]N[sub 4] whiskers or particulates produce superplasticity at a high strain rate of about 0.1s[sup [minus]1]. Superplastic deformation mechanisms of the ceramic whisker or particulate reinforced aluminium alloy composites are fine grain boundary sliding, interfacial sliding at a liquid phase and dynamic recrystallization. An AlN particulate reinforced aluminium alloy composite exhibits a high elastic modulus and a high thermal conductivity, and their thermal expansion is similar to silicon in that the AlN particulate reinforced aluminum alloy composite is expected to apply to semi-conductor packaging in the aerospace structure. In addition, if the composite could produce superplasticity at high strain rates, the market of aerospace application for superplastic composites could be expanded. The purpose of this study is to make clear if an AlN particulate reinforced aluminium alloy composite can produce superplasticity at high strain rate and the superplastic characteristics.

Imai, T. (National Industrial Research Inst. of Nagoya (Japan)); L'Esperance, G.; Hong, B.D. (Ecole Polytechnique de Montreal, Quebec (Canada))

1994-08-01

73

Characterization of stable aluminium-citrate species as reference substances for aluminium speciation by ion chromatography.  

PubMed

Well-defined anionic aluminium-citrate species are accessible from crystalline aluminium complexes. The solution chemistry of those species can be investigated using ion chromatography as a powerful tool for aluminium speciation in aqueous samples. The separation of three anionic aluminium-citrate complexes by anion exchange chromatography is possible within 5 min using isocratic conditions. The element specific detection was done by online coupled ICP-AES. The remaining charge of the complexes after dissolution can be determined by ion chromatography using a retention model. Time-dependent monitoring of the species distribution gave information about the species stabilities and the decomposition pathways. With citric acid as an aluminium chelator partially very stable anionic species are observed. These complexes are important components in biological systems. An example for the practical use of the separation method and the well-defined standards is given for plant sap, which showed two species with similar behavior compared to the investigated stable aluminium-citrate complexes. PMID:16448659

Happel, Oliver; Seubert, Andreas

2006-03-01

74

Electromagnetic stirring of aluminium-silicon alloys  

Microsoft Academic Search

A laboratory-scale electromagnetic stirrer was designed, constructed and tested on two aluminium-silicon alloys with silicon contents of seven and twenty mass per cent. The effect of stirring intensity on the structure of the hypoeutectic alloy was studied and also thermal analysis was performed. For the case of the hypereutectic alloy, the distribution of silicon was determined. The results demonstrate that

D. A. Currey; C. A. Pickles

1988-01-01

75

A Potentiometric Sensing System for Aluminium  

Microsoft Academic Search

A potentiometric flow system based on a sparingly soluble mixture of aluminum laurate and lauric acid as the responsive element and a glass electrode as the primary sensor is reported. Effects of pH adjustment, responses to possible interferent species and the response of the analogous barium sensor to aluminium are also presented.

P. E. Body; P. Stimburys; D. E. Mulcahy

1985-01-01

76

Friction stir welding of aluminium casting alloys  

Microsoft Academic Search

It has been presented the results of testing of friction stir welding quality in relation to EN AC-43200 (AK9) and EN AC-45000 (AK64) aluminium casting alloys. The test joints were made with the use of the welding machine constructed on the basis of numerically controlled milling machines. The assessment of the joints quality was made basing oneself on the visual

Damian Miara; Adam Pietras

2012-01-01

77

Friction stir welding of aluminium plate  

Microsoft Academic Search

Friction stir welding is a novel welding process which is a solid state butt welding process for sheet or plate using the friction phenomenon.This paper describes the effect of the rotation speed of the stir rod and the plate traverse speed during the friction stir welding process on the quality of welded joints. It was found that aluminium plates could

T. Shinoda; Y. Kondo

1997-01-01

78

Two-photon excitation of aluminium phthalocyanines  

SciTech Connect

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

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

1999-12-31

79

Selective laser melting of aluminium components  

Microsoft Academic Search

Previous work has shown that the processing of aluminium alloys by selective laser melting (SLM) is difficult, with reasonable components only being produced with high laser powers (minimum 150W) and slow laser scanning speeds. The high laser power is a significant problem as it is higher than that used in many SLM machines. Also, the combination of high power and

Eleftherios Louvis; Peter Fox; Christopher J. Sutcliffe

80

Modelling recrystallization after hot deformation of aluminium  

Microsoft Academic Search

A physically based model for predicting recrystallization microstructures and textures after hot deformation of aluminium is presented. The modelling approach taken differs from similar models developed for steels. The present model is based on recent experimental investigations directed towards identifying the nature of the nucleation sites for recrystallized grains of different crystallographic orientations. Particle stimulated nucleation, nucleation from cube bands

H. E. Vatne; T. Furu; R. Ørsund; E. Nes

1996-01-01

81

Effect of aluminium chloride on human spermatozoa  

SciTech Connect

Aluminium (Al), which is the most prevalent metal in the earth's crust, has been implicated as an etiological factor in a variety of clinical disorders. Only recently Al has been discussed in the pathogenesis of the parenteral nutrition - associated liver disease. Included in this report are the preliminary findings on its effects on the reproductive functions of human beings.

Kaur, S.

1988-03-01

82

Reuse of steel and aluminium without melting  

E-print Network

and Aluminium  Components at End of Product Life. Environmental Science & Technology, 46(18), 10334–10340. Journal papers (submitted) Cooper, D.R., Skelton, A.C.H., Moynihan, M.C. & Allwood, J.M. 2013. Component level strategies for exploiting the lifespan...

Cooper, Daniel

2014-01-07

83

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

84

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

PubMed

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

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

2008-06-19

85

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

86

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

87

Structure of liquid aluminium-silicon alloys  

Microsoft Academic Search

The Kumar-Samarin technique of centrifuging was adopted to study the structure of aluminium-silicon alloys in terms of the concept of the existence of clusters in liquid state. The investigation shows that in hypo-eutectic alloys the clusters are denser than the monatomic matrix whilst in hyper-eutectic alloys they are lighter. It is suggested that this difference in the distribution of silicon

Manjit Singh; Rajendra Kumar

1973-01-01

88

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.

89

Addition Fun!  

NSDL National Science Digital Library

Students will have the opportunity to practice their additions skills through a variety of addition games. To practice addition, click Memory Addition! Race the clock while learning your addition facts. Click on Flashcard Races. For this last game, come and get me so I can watch and check you addition skills! Click Last Game! ...

Bingham, Mrs.

2007-11-27

90

Mechanical Properties of Particulate Reinforced Aluminium Alloy Matrix Composite  

NASA Astrophysics Data System (ADS)

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

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

2011-01-01

91

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

92

Deep drawing of aluminium–steel tailor-welded blanks  

Microsoft Academic Search

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

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

2008-01-01

93

Addition Facts  

NSDL National Science Digital Library

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

Felsted, Ms.

2010-04-12

94

Effect of the mixing procedure on aluminium (oxide)-hydroxide obtained by precipitation of aluminium nitrate with soda  

Microsoft Academic Search

Three different mixing procedures of aluminium nitrate with soda were compared keeping identical aging conditions (T=60 °C, pH=9, 120-min aging): injection of nitrate aluminium solution into soda, injection of soda into nitrate aluminium solution and double jet. Each procedure led to a specific compound: microporous boehmite, bayerite and fibrillar boehmite, respectively. For single jet procedures, reactions were therefore driven locally

J.-F Hochepied; O Ilioukhina; M.-H Berger

2003-01-01

95

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

Microsoft Academic Search

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

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

2008-01-01

96

The presence and consequences of precipitatefree zones in an aluminium-copper-lithium alloy  

Microsoft Academic Search

The addition of lithium to aluminium alloys has the potential for providing a class of high-strength alloys with exceptional properties suitable for aerospace applications. Potential candidates are precipitation hardenable and belong to the Al-Li-Cu family. The intrinsic microstructural features have a pronounced influence on the mechanical response of these alloys. In this work, the mechanisms responsible for the formation of

T. S. Srivatsan; E. J. Lavernia

1991-01-01

97

Development of a cryopreservation procedure using aluminium cryo-plates.  

PubMed

A cryopreservation procedure using an aluminium cryo-plate was successfully developed using in vitro-grown Dalmatian chrysanthemum (Tanacetum cinerariifolium) shoot tips. Shoot cultures were cold-hardened at 5 degree C on MS medium containing 0.5 M sucrose over a period of 20 to 40 days. Shoot tips with basal plate (1.0-1.5 x 1.0 mm) were dissected from shoot cultures and precultured at 5 degree C for 2 days on MS medium containing 0.5 M sucrose. Precultured shoot tips were placed on aluminium cryo-plates (7 mm x 37 mm x 0.5 mm) with 10 wells (diameter 1.5 mm, depth 0.75 mm) and embedded in alginate gel. Osmoprotection was performed by immersing the cryo-plates for 30 or 60 min in 25 ml pipetting reservoirs filled with loading solution (2 M glycerol + 1.4 M sucrose). For dehydration, the loading solution was replaced with PVS 7M vitrification solution (30 percent glycerol, 19.5 percent ethylene glycol and 0.6 M sucrose in liquid MS basal medium), which was applied for 40 min. After rapid immersion in liquid nitrogen, shoot tips attached to the cryo-plates were rewarmed by immersion in cryotubes containing 2 ml 1 M sucrose solution. Using this procedure, regrowth of cryopreserved shoot tips of line 28v-75 reached 77 degree. This protocol was successfully applied to six additional lines, with high regrowth percentages ranging from 65 to 90 percent. By contrast, the modified vitrification protocol tested as a reference produced only moderate regrowth percentages. This new method displays many advantages and will facilitate large scale cryostorage in genebank. PMID:21766155

Yamamoto, Shin-ichi; Rafique, Tariq; Priyantha, Wickramage Saman; Fukui, Kuniaki; Matsumoto, Toshikazu; Niino, Takao

2011-01-01

98

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

99

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

100

The Effect of Heat Treatment on the Shock Response of the Aluminium Alloy 6061  

NASA Astrophysics Data System (ADS)

The mechanical response of aluminium alloys such as 6061 is manipulated through heat treatment to create a fine distribution of intermetallic particles. Post shock recovered microstructures of similar alloys has shown that in the solution treated (T0) state, with all alloy additions dissolved in the aluminium, deformation occurs via the formation of dislocation cells, in a similar manner to other face centred cubic metals such as copper or nickel. Further, a significant post shock hardening has also been observed, in agreement with the observed increase in dislocation density. In contrast, in the fully aged (T6) material, deformation occurs results in a random distribution of dislocations, with no enhanced hardening. From these previous observations, it is expected that the variation of shock induced shear strength, both with shock amplitude and pulse duration will be significantly different between the two heat treated states, and thus it is these features that this investigation addresses.

Chu, Ming; Jones, Ian; Millett, Jeremy; Bourne, Neil; Gray, Rusty

2009-06-01

101

Equilibrium thermodynamics of nonstoichiometry in ZnO and aluminium doping of ZnO using aluminium chloride  

Microsoft Academic Search

A critical assessment of nonstoichiometry that can occur in zinc oxide at various temperatures and oxygen pressures has been made using the concepts of equilibrium thermodynamics. The feasibility of producing transparent conducting films of aluminium-doped zinc oxide by spray pyrolysis of organo-zinc salt solution containing aluminium chloride is also discussed.

A. Paul; H. N. Acharya

1992-01-01

102

Study on aluminium-based single films.  

PubMed

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

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

2007-12-28

103

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

104

THE LONG-TERM RETENTION IN AND EXCRETION OF ALUMINIUM FROM MAN STUDIED USING 26Al  

Microsoft Academic Search

Until 1990 biokinetic studies of aluminium metabolism and biokinetics in man and other animals had been substantially inhibited by analytical and practical difficulties. Of these, the most important are the difficulties in differentiating between administered aluminium and endogenous aluminium - especially in body fluids and excreta and the problems associated with the contamination of samples with environmental aluminium. As a

N. D. Priest; D. Newton

105

Aluminium Ions in Aluminium Hydroxide, Phosphate and Soil-Water Systems  

Microsoft Academic Search

IN recent years attention has been given to the solubility of aluminium phosphates in soils. Of the synthetic preparations examined, variscite, Al(OH)2H2PO4, has been most extensively investigated and criteria for its existence in soils evaluated1. It has been assumed that the solubility product of variscite can be determined from the activities of the ionic species in the expression Ksp =

M. Raupach

1960-01-01

106

A quest for super dense aluminium  

NASA Astrophysics Data System (ADS)

The extreme pressure phase diagram of materials is important not only for understanding the interiors of planets or stars, but also for the fundamental understanding of the relation between crystal structure and electronic structure. Structural transitions induced by extreme pressure are governed by the deformation of valence electron charge density which bears the brunt of increasing compression while the relative volume occupied by the nearly incompressible ionic core electrons increases. At extreme pressures common materials are expected to transform into new dense phases with extremely compact atomic arrangements that may also have unusual physical properties. In this report, we present new experiments carried out on aluminium. A simple system like Al is not only important as a benchmark for theory, but can also be used as a standard for pressures in the TPa range and beyond which are targeted at new dynamic compression facilities such as the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory in the US or Laser Mégajoule (LMJ) in Bordeaux in France. For aluminium, first principle calculations have consistently predicted a phase transition sequence from fcc to hcp and hcp to bcc in a pressure range below 0.5 TPa [Tambe et al., Phys. Rev. B 77, 172102, 2008]. The hcp phase was identified at 217 GPa in a recent experiment [Akahama et al., Phys. Rev. Lett. 96, 45505, 2006] but the detection of the predicted bcc phase has been hampered by the difficulty of routine static high pressure experiments beyond 350 GPa. Here, we report on the overcoming of this obstacle and the detection of all the structural phase transitions predicted in Al by achieving a pressure in excess of 500 GPa in the static regime in a diamond-anvil cell. In particular, using X-ray diffraction at the high-pressure beamline ID27 at the European Synchrotron Radiation Facility (ESRF), we find a bcc super-dense phase of aluminium at a pressure of 380 GPa. In this report, we provide detailed information on this phase transition as well as details on how to achieve controlled static experiments in the range 3 to 5 Mbar.

Fiquet, G.; Narayana, C.; Bellin, C.; Shukla, A.; Esteve, I.; Mezouar, N.

2013-12-01

107

Unreported cardiac arrhythmias in aluminium worker.  

PubMed

Aluminium (Al) is the third most prevalent element, representing approximately 8% of total mineral components in the earth's crust (1). Chronic exposure to Al is mainly encountered at particular work places, for example, in foundries or in the Al powder industry, as an occupational exposure. In case of occupational Al exposure, inhalation is the main route of uptake. Chronic exposure to Al is associated with skeletal, neurological, hematological and lung changes. Studies regarding the Al powder industry showed that long-term inhalative exposure to Al can induce pulmonary fibrosis (2). Although there is only one report about ventricular tachycardia as a cardiac manifestation in occupationally exposed persons (3), in this report, we presented a case that had Mobitz type I second-degree atrioventricular block and nonsustained ventricular tachycardia. To our knowledge, this is the first report in chronic poisoning. PMID:23906291

Yildiz, Mustafa; Kocabay, Gonenc

2013-08-01

108

Ladybug Addition  

NSDL National Science Digital Library

"This is an interesting lesson on addition that encourages class participation through role-play and concrete hands-on activity. Students practice putting two sets together to form a new set." (from Beacon Learning Center)

Center, Beacon L.

2008-12-16

109

Fractal property of backscattered acoustic signals from polycrystalline aluminium  

NASA Astrophysics Data System (ADS)

Backscattered acoustic signals from annealed polycrystalline aluminium are observed to possess fractal characteristics. Assuming this to be true a grain size distribution is deduced which is seen to match the distribution obtained experimentally in polycrystalline materials.

Barat, P.; De, Subhranil; Bandyopadhyay, S. K.

1998-08-01

110

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 as a #12;2 Johannes Roth et al pollution. Or they can stay in the hole and fill it up. Void formation

Roth, Johannes

111

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

112

Characterization of rapidly solidified aluminium-silicon alloy  

Microsoft Academic Search

A metallographic investigation of as-cast LM-13 aluminium-silicon alloy, solidified at different cooling rates (using permanent moulds or a single-roll melt spinner), is presented with special reference to the modification of eutectic silicon. and the refinement of primary aluminium. The refinement of microstructure with the increase in cooling rate is mainly attributed to the limited growth kinetics of the nucleated phase

S. Das; A. H. Yegneswaran; P. K. Rohatgi

1987-01-01

113

Fortlpande miljanalys vid SLU Aluminiums vg frn mark till vatten  

E-print Network

Fortlöpande miljöanalys vid SLU www.slu.se Aluminiums väg från mark till vatten Oorganiskt aluminium frigörs till bäckarna om till exempel vattnet är mycket surt och det inte finns tillräckligt med effektiva sättet att minska aluminiumläckaget till vattendragen är sannolikt att kalka områden där

114

Neutron Radiographic Detection of Surface Corrosion on Aluminium  

Microsoft Academic Search

The contrast sensitivity of neutron radiographic detection of corrosion products in aluminium is nearly one order of magnitude better than with soft (30 kV) X-ray radiography. With neutron radiography quantitative measurements of the depth of surface corrosion of aluminium objects can be effectively performed. Experimentally it has been confirmed that through I cm thick Al slab approximately 0.1–0.2 mm thick

J. Rant; R. Ilié; G. Pregl; S. Demirovi?

1986-01-01

115

Polychlorinated dibenzodioxins and dibenzofurans in the aluminium recycling process  

Microsoft Academic Search

At a pilot-scale rotary furnace, aluminium scrap, to which organic material was attached, was molten together with salt at temperatures of ?700–800°C. Because these conditions are favorable for the production of polychlorinated dibenzodioxins and dibenzofurans (PCDD\\/F) the following measures were investigated to reduce PCDD\\/F emissions from the aluminium recycling process: (a) alternative duct configuration; (b) type of scrap feeding; and

A Kaune; K.-W Schramm; R Lehnardt; A Kettrup; I Ollenschläger; H Rossel

1999-01-01

116

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

117

8 Vand & Jord Aluminium(Al)-behandling, som en restaure-  

E-print Network

ændret karakter til en næringsrig sø med uklart vand pga. stor algevækst, en skæv fiskebestand og næsten-pulje sker stort set ikke pga. sæsonvariation i vandtransporten med meget lave sommerværdier. I 2002 afgav med aluminium? Er det kun omsætningen af fosfor som ændres pga. bindingen til aluminium, eller ændrer

Andersen, Frede Ã?.

118

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

119

Reduction of turbidity by a coal-aluminium filter  

SciTech Connect

Coal-aluminium granular filters successfully reduce turbidity in low-alkalinity raw waters to less than 1.0 ntu, without a coagulation step or external coagulant aids. Data from experiments conducted with control and pilot-plant filters show the viability of the process and indicate the turbidity and retention mechanisms. Operational characteristics of the process are similar to those of a conventional filter. The costs of the coal-aluminium process compare favourably with those of traditional treatment.

Collins, A.G.; Johnson, R.L.

1985-06-01

120

Study of fatigue behaviour of 7475 aluminium alloy  

Microsoft Academic Search

Fatigue properties of a thermomechanically treated 7475 aluminium alloy have been studied in the present investigation. The\\u000a alloy exhibited superior fatigue life compared to conventional structural aluminium alloys and comparable stage II crack growth\\u000a rate. It was also noticed that the fatigue crack initiated from a surface grain and the crack extension was dominated by ductile\\u000a striations. Analysis also revealed

B. B. Verma; J. D. Atkinson; M. Kumar

2001-01-01

121

Volatilisation and oxidation of aluminium scraps fed into incineration furnaces.  

PubMed

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. PMID:22749723

Biganzoli, Laura; Gorla, Leopoldo; Nessi, Simone; Grosso, Mario

2012-12-01

122

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

123

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

124

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

NASA Astrophysics Data System (ADS)

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

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

2009-06-01

125

Modulation of the human immune response by the non-toxic and non-pyrogenic adjuvant aluminium hydroxide: effect on antigen uptake and antigen presentation.  

PubMed Central

The regulatory effects of an adjuvant (aluminium hydroxide) on the early phase of the immune response have been investigated. Adsorbing a soluble antigen (tetanus toxoid) to aluminium hydroxide led to a significant increase (P less than 0.001) in antigen-induced T-cell proliferation (macrophage-T-cell interaction, MTI) making aluminium hydroxide-adsorbed antigens especially suitable to study immunoregulatory changes in the early phase of the immune response. First studies revealed that this increase was due to an enhancement of antigen uptake by the antigen-presenting cell. However, under conditions allowing for the uptake of comparable amounts of soluble (TTs) or aluminium hydroxide-absorbed (TTAL) antigen, T-cell proliferation in response to TTAL was still higher than in response to TTS. This difference was especially pronounced if suboptimal antigen concentrations were used and could be explained by differences in the TTS-versus TTAL-induced release of interleukin-1 (IL-1). Pulsing with TTAL led to a substantial increase in IL-1 release by monocytes (MO) which then subsequently augmented antigen-induced T-cell proliferation. This was further supported by addition of exogenous IL-1 to cultures of T cells and TTS-pulsed MOs, which also significantly increased the T cells' proliferative response. These findings demonstrate that in the early phase of the immune response, aluminium hydroxide exerts its regulatory effect at the level of the antigen-presenting and mediator-releasing accessory cell. PMID:3876178

Mannhalter, J W; Neychev, H O; Zlabinger, G J; Ahmad, R; Eibl, M M

1985-01-01

126

Study on the content of aluminium and heavy metals in puffed food by ICP AES with microwave digestion  

Microsoft Academic Search

A method was studied for the analysis of aluminium and heavy metals in puffed food by ICP- AES with microwave digestion. The contents of Al, As, Pb, Cd and Ni were determined in 20 kinds of puffed food. The addition recovery rates was between 91.0 and 105.0 %, and the relative standard deviation was lower than 6.35%. The results showed

Wang Hongliang; Fan Wenxiu

2011-01-01

127

The biological behaviour and bioavailability of aluminium in man, with special reference to studies employing aluminium-26 as a tracer: review and study update.  

PubMed

Until 1990 biokinetic studies of aluminium metabolism and biokinetics in man and other animals had been substantially inhibited by analytical and practical difficulties. Of these, the most important are the difficulties in differentiating between administered aluminium and endogenous aluminium-especially in body fluids and excreta and the problems associated with the contamination of samples with environmental aluminium. As a consequence of these it was not possible to detect small, residual body burdens of the metal following experimental administrations. Consequently, many believed aluminium to be quantitatively excreted within a short time of uptake in all, but renal-failure patients. Nevertheless, residual aluminium deposits in a number of different organs and tissues had been detected in normal subjects using a variety of techniques, including histochemical staining methods. In order to understand the origins and kinetics of such residual aluminium deposits new approaches were required. One approach taken was to employ the radioisotope (67)Ga as a surrogate, but this approach has been shown to be flawed-a consequence of the different biological behaviours of aluminium and gallium. A second arose from the availability, in about 1990, of both (26)Al-a rare and expensive isotope of aluminium-and accelerator mass spectrometry for the ultra-trace detection of this isotope. Using these techniques the basic features of aluminium biokinetics and bioavailability have been unravelled. It is now clear that some aluminium is retained in the body-most probably within the skeleton, and that some deposits in the brain. However, most aluminium that enters the blood is excreted in urine within a few days or weeks and the gastrointestinal tract provides an effective barrier to aluminium uptake. Aspects of the biokinetics and bioavailability of aluminium are described below. PMID:15152306

Priest, N D

2004-05-01

128

Double layer, diluent and anode effects upon the electrodeposition of aluminium from chloroaluminate based ionic liquids.  

PubMed

The deposition of aluminium from a chloroaluminate based ionic liquid was studied to elucidate the effect of a diluent (toluene) and electrolyte (LiCl) on the deposit morphology. A wide variety of analytical techniques was applied to this system to determine the speciation and mechanism of material growth. These included: (27)Al NMR, FAB-MS, cyclic voltammetry, chronocoulometry, chronopotentiometry, scanning electron microscopy and atomic force microscopy. It was found that under-potential deposition (upd) causes a change in the way in which metal grows on the electrode surface. Metal grows in two regimes which are believed to be nano-material and bulk material. The addition of toluene causes a change in speciation and a decrease in upd which in turn changes the morphology of the deposit obtained and can lead to mirror finish aluminium. The addition of LiCl has the opposite effect encouraging upd and leading to larger crystallites and a dark grey deposit. It is also shown for the first time that under many conditions the rate of the anodic dissolution process is overall rate controlling and one effect of the addition of toluene is to increase the rate of anodic dissolution. PMID:20145853

Abbott, Andrew P; Qiu, Fulian; Abood, Hadi M A; Ali, M Rostom; Ryder, Karl S

2010-02-28

129

Effects of aqueous aluminium on four fish ectoparasites.  

PubMed

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

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

2006-10-01

130

Contribution of electrostatic and hydrophobic interactions to the adsorption of proteins by aluminium-containing adjuvants  

Microsoft Academic Search

The effect of ionic strength and ethylene glycol on the adsorption of bovine serum albumin (BSA) or lysozyme by a commercial aluminium hydroxide or aluminium phosphate adjuvant was studied at pH 7.4 and 25°C. The adsorption of BSA by aluminium hydroxide adjuvant and lysozyme by aluminium phosphate adjuvant was found to be inversely related to ionic strength. This indicates that

Ragheb H. Al-Shakhshir; Fred E. Regnier; Joe L. White; Stanley L. Hem

1995-01-01

131

Aluminium Electrodes Effect the Operation of Titanium Oxide Sol-gel Memristors  

Microsoft Academic Search

By a comparison between memristors made with aluminium and gold electrodes, this letter demonstrates that aluminium electrodes are an essential component of the TiO$_2$ sol-gel flexible memristor . Both slow varying `analogue' and sudden switching `digital' memristor devices have been observed. Limiting the oxygen exposure of the bottom aluminium electrode favours the creation of digital memristors over analogue ones. A

Ella Gale; David Pearson; Stephen Kitson; Andrew Adamatzky; Ben de Lacy Costello

2011-01-01

132

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

133

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

Microsoft Academic Search

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

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

134

Dehydration of 2-Methylbutanal and Methyl Isopropyl Ketone to Isoprene Using Boron and Aluminium Phosphate Catalysts  

Microsoft Academic Search

The synthesis of isoprene from the dehydration of 2-methylbutanal is described using boron phosphate, aluminium phosphate, and mixed boron\\/aluminium phosphates as catalysts. Both boron phosphate and aluminium phosphate deactivate steadily with reaction time due to loss of catalyst activity but the selectivity to isoprene is not significantly affected by catalyst deactivation. Catalyst deactivation is shown to be due to two

Graham J. Hutchings; Ian D. Hudson; Donald Bethell; Don G. Timms

1999-01-01

135

High-strength aluminium alloys for welded structures in the aircraft industry  

Microsoft Academic Search

From the viewpoint of demand and production, aluminium and its alloys take only second place to steels. Because of their advantageous combination of physical, mechanical, anticorrosive and processing properties, aluminium-based light alloys find their place not only in aircraft constructions, but also in other branches of industry and general building. The range of applications for aluminium alloys is wide, especially

A Ya Ishchenko

2005-01-01

136

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

PubMed

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

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

1991-01-01

137

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

138

Predicting the adsorption of proteins by aluminium-containing adjuvants.  

PubMed

The adsorption of two model proteins, albumin and lysozyme, by boehmite or amorphous aluminium hydroxyphosphate adjuvants was studied. Electrostatic, attraction has a major role in adsorption. At physiological pH, boehmite, which has a point of zero charge above 7.35, extensively adsorbed albumin, which has an isoelectric point of 4.8, but was not effective in adsorbing lysozyme (isoelectric point, 11.0). Conversely, amorphous aluminium hydroxyphosphate (point of zero charge, 4.0) was effective in adsorbing lysozyme but adsorbed relatively little albumin. The results suggest that the selection of either boehmite or amorphous aluminium hydroxyphosphate as an adjuvant should be based in part on the isoelectric point of the antigen. PMID:2042392

Seeber, S J; White, J L; Hem, S L

1991-03-01

139

Different Approach to the Aluminium Oxide Topography Characterisation  

NASA Astrophysics Data System (ADS)

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; Raos, Pero; Stoic, Antun

2007-04-01

140

Aluminium leaching using chelating agents as compositions of food.  

PubMed

In this work, we study aluminium (Al) leaching using three chelating agents (lactic acid, oxalic acid, and citric acid) that are commonly found in foods and beverages. We test acids, sodium, potassium and lithium salts of these three chelating agents. Aluminium concentrations are determined by using Graphite Furnace Atomic Absorption Spectrometry (GFAAS) after a one hour incubation of the aluminium with the chelating agent. We study three concentrations corresponding to the lower, median, and to the higher levels of these substances that are commonly found in consumable foods. We select ambient and boiling temperatures for the incubation. We found that at ambient temperature, the variation of Al leaching depends on the chemical form. Al leaching is significantly higher at 100 degrees C than at the ambient temperature. The salty form for the composition releases more Al than the acidic form. PMID:17434655

Karbouj, Rim

2007-09-01

141

Synthesis and characterization of a new aluminium-based compound.  

PubMed

A new aluminium polynuclear crystalline species, Al(13)(OH)(30)(H(2)O)(15)Cl(9) has been synthesized and characterized. It is a particular case of the Al(13)(OH)(30-y)(H(2)O)(18-x)Cl(9) x zH(2)O family. It has been obtained from aluminium waste cans treated with HCl solution in strong acid media, followed by an ageing period. The crystalline structure of the complex was determined by XRD spectroscopy. Twelve reflections were found and indexed with the DICVOL04 software. Morphologically, a flattened preferred orientation was observed by SEM and FESEM. The chemical structure was studied by several absorption spectroscopy techniques: FTIR, ATR-FTIR and Raman dispersion spectroscopy. The coordination of the aluminium nuclei was determined by Al-MAS-NMR. Only octahedral sites were observed. Thermal characterization of the compound was performed by evolved gas analysis (EGA) coupled to simultaneous TGA-DSC. PMID:19655063

Pascual-Cosp, José; Artiaga, Ramón; Corpas-Iglesias, Francisco; Benítez-Guerrero, Mónica

2009-08-28

142

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

143

Enclosed surface laser ablation of laminated aluminium foil  

NASA Astrophysics Data System (ADS)

In this paper, the work reported has concentrated upon a laminated metallised polymer film. A vacuum deposited aluminium layer (˜0.5 ?m) is sandwiched between two layers of oriented polypropylene (OPP) film whose thickness varies from 20 to 40 ?m. Aluminium has been removed from selected areas of this sealed system without breaking the seal or causing damage to the OPP film using a 75 W Q-switched Nd:YAG laser. The mechanisms involved in this new process have been investigated.

Stewart, R.; Li, L.; Thomas, D.

2000-02-01

144

Geometry effects at atomic-size aluminium contacts  

NASA Astrophysics Data System (ADS)

We present electronic structure calculations for aluminium nanocontacts. Addressing the neck of the contact, we compare characteristic geometries to investigate the effects of the local aluminium coordination on the electronic states. We find that the Al 3p z states are very sensitive against modifications of the orbital overlap, which has serious consequences for the transport properties. Stretching of the contact shifts states towards the Fermi energy, leaving the system instable against ferromagnetic ordering. By spacial restriction, hybridization is locally suppressed at nanocontacts and the charge neutrality is violated. We discuss the influence of mechanical stress by means of quantitative results for the charge transfer.

Schwingenschlögl, U.; Schuster, C.

2007-05-01

145

Towards an understanding of the adjuvant action of aluminium  

PubMed Central

The efficacy of vaccines depends on the presence of an adjuvant in conjunction with the antigen. Of these adjuvants, the ones that contain aluminium, which were first discovered empirically in 1926, are currently the most widely used. However, a detailed understanding of their mechanism of action has only started to be revealed. In this Timeline article, we briefly describe the initial discovery of aluminium adjuvants and discuss historically important advances. We also summarize recent progress in the field and discuss their implications and the remaining questions on how these adjuvants work. PMID:19247370

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

2011-01-01

146

Application of Fluorimetric Methods for Selected Additives Determination in Food Products  

Microsoft Academic Search

Simple and sensitive spectrofluorimetric method for phosphorus determination in food samples after mi - crowave mineralisation has been described. The proposed method is based on the formation of a fluorescent chelate between morin and aluminium and the fluorescence quenching after addition of phosphates solution. Additionally, the method with quinine sulphate was modified and applied for food samples. The proposed procedures

M. Kurzawa; E. Sz?y K

147

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

PubMed Central

A pollution gradient was observed in tree foliage sampled in the vicinity of a large aluminium production facility in Patagonia (Argentina). Leaves of Eucalyptus rostrata, and Populus hybridus and different needle ages of Pinus spec. were collected and concentrations of aluminium (Al) and sulphur (S) as well as physiological parameters (chlorophyll and lipid oxidation products) were analyzed. Al and S concentrations indicate a steep pollution gradient in the study showing a relationship with the physiological parameters in particular membrane lipid oxidation products. The present study confirms that aluminium smelting results in high Al and sulphur deposition in the study area, and therefore further studies should be carried out taking into account potentially adverse effects of these compounds on human and ecosystem health. PMID:22654642

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

2012-01-01

148

Do oral aluminium phosphate binders cause accumulation of aluminium to toxic levels?  

PubMed Central

Background Aluminium (Al) toxicity was frequent in the 1980s in patients ingesting Al containing phosphate binders (Alucaps) whilst having HD using water potentially contaminated with Al. The aim of this study was to determine the risk of Al toxicity in HD patients receiving Alucaps but never exposed to contaminated dialysate water. Methods HD patients only treated with Reverse Osmosis(RO) treated dialysis water with either current or past exposure to Alucaps were given standardised DFO tests. Post-DFO serum Al level > 3.0 ?mol/L was defined to indicate toxic loads based on previous bone biopsy studies. Results 39 patients (34 anuric) were studied. Mean dose of Alucap was 3.5 capsules/d over 23.0 months. Pre-DFO Al levels were > 1.0 ?mol/L in only 2 patients and none were > 3.0 ?mol/L. No patients had a post DFO Al levels > 3.0 ?mol/L. There were no correlations between the serum Al concentrations (pre-, post- or the incremental rise after DFO administration) and the total amount of Al ingested. No patients had unexplained EPO resistance or biochemical evidence of adynamic bone. Conclusions Although this is a small study, oral aluminium exposure was considerable. Yet no patients undergoing HD with RO treated water had evidence of Al toxicity despite doses equivalent to 3.5 capsules of Alucap for 2 years. The relationship between the DFO-Al results and the total amount of Al ingested was weak (R2 = 0.07) and not statistically significant. In an era of financial prudence, and in view of the recognised risk of excess calcium loading in dialysis patients, perhaps we should re-evaluate the risk of using Al-based phosphate binders in HD patients who remain uric. PMID:21992770

2011-01-01

149

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

NASA Astrophysics Data System (ADS)

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 can be achieved. The development, production and testing of parts built up by a laser powder bed process will be presented with regard to the qualification of the new material concept “ScalmalloyRP®” for laser additive manufacturing.

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

150

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

151

Foaming of aluminium-silicon alloy using concentrated solar energy  

Microsoft Academic Search

Solar energy is used for the work reported here as a nonconventional heating system to produce aluminium foam from Al-Si alloy precursors produced by powder metallurgy. A commercial precursor in cylindrical bars enclosed in a stainless-steel mould was heated under concentrated solar radiation in a solar furnace with varied heating conditions (heating rate, time, and temperature). Concentrated solar energy close

L. E. G. Cambronero; J. M. Ruiz-Roman; I. Canadas; D. Martinez

2010-01-01

152

Severe wear of a near eutectic aluminium–silicon alloy  

Microsoft Academic Search

The severe wear of a near eutectic aluminium–silicon alloy is explored using a range of electron microscopic, spectroscopic and diffraction techniques to identify the residually strained and unstrained regions, microcracks and oxidized regions in the subsurface. In severe wear the contact pressure exceeds the elastic shakedown limit. Under this condition the primary and eutectic silicon particles fragment drastically. The fragments

Anirban Mahato; Nisha Verma; Vikram Jayaram; S. K. Biswas

2011-01-01

153

Foaming of aluminium–silicon alloy using concentrated solar energy  

Microsoft Academic Search

Solar energy is used for the work reported here as a nonconventional heating system to produce aluminium foam from AlSi alloy precursors produced by powder metallurgy. A commercial precursor in cylindrical bars enclosed in a stainless-steel mould was heated under concentrated solar radiation in a solar furnace with varied heating conditions (heating rate, time, and temperature). Concentrated solar energy close

L. E. G. Cambronero; I. Cañadas; D. Martínez; J. M. Ruiz-Román

2010-01-01

154

High Speed Face Milling of a Aluminium Silicon Alloy Casting  

Microsoft Academic Search

High speed machining of aluminium silicon alloy castings has gained significant interest from automotive industry involved in the development of the new generation of lightweight vehicles. This paper investigates the influence of workpiece microstructure, namely the secondary dendritic arm spacing (SDAS), tool material and geometry on tool wear mechanisms, cutting forces and surface integrity when face milling at cutting speeds

E-G Ng; D. Szablewski; M. Dumitrescu; M. A. Elbestawi; J. H. Sokolowski

2004-01-01

155

Structure of rapidly solidified aluminium-silicon alloys  

Microsoft Academic Search

This paper present results obtained on rapid solidification of aluminium-silicon alloys from the liquid state. It shows that the limit of primary solid solubility is extended almost to the eutectic composition and that the large supersaturation is relieved on raising the annealing temperature to the range 110 to 450° C. This conclusion is based on measurements of lattice parameter and

S. K. Bose; R. Kumar

1973-01-01

156

High-Rate Compaction of Aluminium Alloy Foams  

Microsoft Academic Search

The response of aluminium foams to impact can be categorised according to the impact velocity. Tests have been carried out at a range of impact velocities from quasi-static to velocities approaching the speed of sound in the foam. Various experimental arrangements have been employed including pneumatic launcher tests and plate impact experimants at velocities greater than 1000 m s?1. The

J. J. Harrigan; Y.-C. Hung; P. J. Tan; N. K. Bourne; P. J. Withers; S. R. Reid; J. C. F. Millett; A. M. Milne

2006-01-01

157

High-Rate Compaction of Aluminium Alloy Foams  

Microsoft Academic Search

The response of aluminium foams to impact can be categorised according to the impact velocity. Tests have been carried out at a range of impact velocities from quasi-static to velocities approaching the speed of sound in the foam. Various experimental arrangements have been employed including pneumatic launcher tests and plate impact experimants at velocities greater than 1000 m s-1. The

J. J. Harrigan; Y.-C. Hung; P. J. Tan; N. K. Bourne; P. J. Withers; S. R. Reid; J. C. F. Millett; A. M. Milne

2006-01-01

158

Investigations on solution derived aluminium doped zinc oxide thin films  

Microsoft Academic Search

Aluminium (Al) doped transparent zinc oxide thin films have been successfully grown on sapphire (0001) substrates by an economical chemical solution deposition technique. These films were characterized in terms of their structural, optical, and electrical properties. Detailed XPS analysis of the O1s core level spectra has been carried out for the ZnO films annealed at different temperatures. Lower binding energy

S. B Majumder; M Jain; P. S Dobal; R. S Katiyar

2003-01-01

159

Examples of liquiq metal embrittlement in industrial aluminium alloys  

Microsoft Academic Search

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

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

2002-01-01

160

Microstructural Evolution and Age Hardening in Aluminium Alloys  

Microsoft Academic Search

This paper examines the microstructural evolution in selected aluminium alloys based on commercial age hardenable 2000, 6000, and 7000 series alloys. Atom probe field-ion microscopy and transmission electron microscopy have been used to examine the effects of microalloying and the origins of hardening. The combined application of these techniques is particularly important in the study of nanoscale precipitation processes. It

S. P. Ringer; K. Hono

2000-01-01

161

Modelling of friction stir welding of 7xxx aluminium alloys  

Microsoft Academic Search

A combined modelling approach was applied to predict the behaviour of high strength 7000 aluminium alloys. Thermal modelling, microstructure modelling and strength modelling were performed in succession to give some insight into the complex precipitation mechanism occurring during friction stir welding (FSW). A quantitative assessment of a recent numerical model to predict the evolution of the precipitate distribution is performed

N. Kamp; A. Sullivan; J. D. Robson

2007-01-01

162

Microstructural Modelling for Friction Stir Welding of Aluminium Alloys  

Microsoft Academic Search

Predictive models have been developed to calculate the hardness profile and precipitate distribution after friction stir welding of aerospace aluminium alloys. A coupled modelling approach has been used, linking a thermal model to predict the thermal cycle to microstructure and property models. Two levels of modelling have been considered. The first is a semi-empirical approach that predicts hardness profiles. This

J. D. Robson; N. Kamp; A. Sullivan

2007-01-01

163

FEM MODEL FOR FRICTION STIR WELDING OF ALUMINIUM  

Microsoft Academic Search

Despite significant advances in the application of FSW, as a relatively new welding technique for welding aluminium alloys, the fundamental knowledge of such thermal impact and thermomechanical processes are still not completely understood. The paper introduces an original 3D FEM model of Friction Stir Spot Welding phases. The outputs are the thermal, the stresses and strain fields, respectively. The recently

Dan Birsan; Danut Iordachescu; Jose Luis Ocana; Pedro Vilaca

164

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

165

Galvanic corrosion of laser weldments of AA6061 aluminium alloy  

Microsoft Academic Search

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

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

2007-01-01

166

Review article Aluminium toxicity in plants: a review  

E-print Network

Review article Aluminium toxicity in plants: a review G.R. ROUTa, S. SAMANTARAYb, P. DASb* a Plant Biotechnology Division, Regional Plant Resource Centre, Bhubaneswar- 751 015, Orissa, India b Plant Physiology and Biochemistry Laboratory, Regional Plant Resource Centre, Bhubaneswar- 751 015, Orissa, India (Received 31 May

Paris-Sud XI, Université de

167

Hot and warm forming of 2618 aluminium alloy  

Microsoft Academic Search

The hot and warm formability of 2618 aluminium alloy, in the as-solutioned condition, was investigated in extended ranges of temperature and strain rate by means of torsion testing. Precipitation was found to occur during deformation. The effect of the precipitation of second phase particles, occurring during deformation, on the flow curve shape and on the stress level was evaluated. At

P Cavaliere

2002-01-01

168

Characterisation of aluminium alloy 6061 for the ultrasonic consolidation process  

Microsoft Academic Search

Ultrasonic consolidation (UC) is a freeform fabrication technique developed for the layered fabrication of metal parts. The process uses a high intensity ultrasonic energy source to induce combined static and oscillating shear forces within layers of metal foil to produce solid-state bonds. This paper will consider control parameter optimisation and surface preparation issues, for the production of aluminium alloy 6061

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

2003-01-01

169

Carbon capture and the aluminium industry: preliminary studies  

Microsoft Academic Search

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

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

2006-01-01

170

Thin-film cryogenic resistors from aluminium alloys  

NASA Astrophysics Data System (ADS)

The temperature dependence of the resistances of thin films sputtered from three commercially available aluminium alloys (5052, 5086, 5456) has been measured in the temperature range 1.5-4.2 K. The 5052-alloy films had a positive temperature coefficient of resistance (TCR) throughout this temperature range, whereas films of the other two alloys had a negative TCR.

Tadros, N. N.; Holdeman, L. B.

171

Overcoming barriers to understanding the cellular basis of aluminium resistance  

Microsoft Academic Search

There appears to be an emerging consensus that resistance to aluminium (Al) is mediated at the cellular level. Virtually all current hypotheses which seek to explain the basis of Al resistance have a cellular focus, including those which postulate that external mechanisms limit the rate of Al entry across the membrane and\\/or protect sensitive extracellular sites, as well as those

Gregory J. Taylor

1995-01-01

172

Recovery of valuable materials from aluminium salt cakes  

Microsoft Academic Search

Salt cakes, which are nominally waste products derived from aluminium dross melting furnaces, are complex mixtures of some 20 different compounds made up of many different elements. Normally they are regarded as waste products and they are disposed of in toxic waste dumps. However, it is shown here that some components are readily recoverable as high-grade products for recycling or

W. J. Bruckard; J. T. Woodcock

2009-01-01

173

Design optimisation of aluminium recycling processes using Taguchi technique  

Microsoft Academic Search

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

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

2002-01-01

174

Corrosion resistance of repair welded naval aluminium alloys  

Microsoft Academic Search

If after welding of aluminium ship hulls at the shipyards or even during service defects are detected in the vicinity of the weldment, repairs are used to extend service life. The method usually followed comprises mechanical removal of part of the weld and redeposition of the filler wire using the same parameters. Such a repair approach unavoidably subjects the remaining

S. Katsas; J. Nikolaou; G. Papadimitriou

2007-01-01

175

Aluminium alloy-solid lubricant talc particle composites  

Microsoft Academic Search

This paper describes the method of synthesizing cast aluminium alloy talc particulate composites and their mechanical and wear properties. Talc particles were characterized using X-ray diffraction, infrared spectroscopy and differential thermal analysis techniques. Composites with two Al-Si alloys (LM 13 and LM 6) as matrices were prepared by heating the molten alloys to 750° C and adding the preheated talc

A. K. Jha; T. K. Dan; S. V. Prasad; P. K. Rohatgi

1986-01-01

176

Vacuum-free diffusion bonding of aluminium metal matrix composite  

Microsoft Academic Search

Owing to their high specific strength aluminium metal–matrix composites (Al-MMC) are becoming popular for many critical engineering applications. These materials are prepared by controlled melting and solidification processing. In order to broaden their applications further, it is necessary to develop suitable joining techniques. Due to the metallurgical nature of these materials, conventional fusion welding techniques such as arc welding cannot

C. S Lee; H Li; R. S Chandel

1999-01-01

177

Retention of ferrite in AluminiumAlloyed TRIPassisted steels  

E-print Network

Retention of ­ferrite in Aluminium­Alloyed TRIP­assisted steels Young Joo Choi1, Dong­Woo Suh1 to probe the data. Solidification experiments are reported in order to test the non­ equilibrium retention here. The purpose of the present work was to study the retention of ­ferrite in detail using the TCFE6

Cambridge, University of

178

Aluminium Phosphide Poisoning: A Growing Concern in Pediatric Population  

Microsoft Academic Search

Aluminium phosphide (ALP), a cheap and freely available pesticide, has emerged a common agent responsible for poisoning in children with a resultant high mortali- ty(1). The poisoning is usually accidental in children but may be suicidal in adoles- cents(2). Twenty cases of ALP poisoning aged between 7-12 years who were admitted in the Pediatric Emergency Services between July 1995 to

INDIAN PEDIATRICS

1997-01-01

179

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

180

Standardization and validation of a new atomic absorption spectroscopy technique for determination and quantitation of aluminium adjuvant in immunobiologicals.  

PubMed

In the present study, Aluminium quantification in immunobiologicals has been described using atomic absorption spectroscopy (AAS) technique. The assay was found to be linear in 25-125 microg/ml Aluminium range. The procedure was found to be accurate for different vaccines with recoveries of external additions ranging between 93.26 and 103.41%. The mean Limit of Variation (L.V.) for both intra- and inter-assay precision was calculated to be 1.62 and 2.22%, respectively. Further the procedure was found to be robust in relation to digestion temperature, alteration in acid (HNO(3) and H(2)SO(4)) ratio used for sample digestion and storage of digested vaccine samples up to a period of 15 days. After validation, AAS method was compared for its equivalency with routinely used complexometric titration method. On simultaneously applying on seven different groups of both bacterial and viral vaccines, viz., DPT, DT, TT, Hepatitis-A and B, Antirabies vaccine (cell culture) and tetravalent DPT-Hib, a high degree of positive correlation (+0.85-0.998) among AAS and titration methods was observed. Further AAS method was found to have an edge over complexometric titration method that a group of vaccines, viz., ARV (cell culture, adsorbed) and Hepatitis-A, in which Aluminium estimation is not feasible by pharmacopoeial approved complexometric titration method (possibly due to some interference in the sample matrix), this newly described and validated AAS assay procedure delivered accurate and reproducible results. PMID:17644407

Mishra, Arti; Bhalla, Sumir Rai; Rawat, Sameera; Bansal, Vivek; Sehgal, Rakesh; Kumar, Sunil

2007-10-01

181

Crystal morphology of unmodified aluminium-silicon eutectic microstructures  

NASA Astrophysics Data System (ADS)

The crystallography of eutectic silicon in an unmodified A1-12.7 wt% Si alloy has been studied by transmission electron microscopy and diffraction of thin films cut from bulk samples. Twinning mechanisms are described by which the silicon changes direction or adjusts interflake spacing at the solid-liquid interface. The branching mechanism observed by previous workers is confirmed but found to be infrequent at moderate freezing rates. A side-branching mechanism is described which is considered to be the primary mechanism for branching in the wheatsheaf configuration. Orientation relationships between the eutectic silicon and aluminium phases are described. These differ from those previously observed in thin films drawn from the melt. It is proposed that orientation relationships vary with freezing rate. Evidence is presented that the eutectic aluminium re-nucleates repeatedly during growth of a single eutectic grain.

Shamsuzzoha, M.; Hogan, L. M.

1986-08-01

182

Results of the Experiment: Welding of Aluminium Alloy in Microgravity  

NASA Astrophysics Data System (ADS)

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

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

2002-01-01

183

Recovery of the actinides by electrochemical methods in molten chlorides using solid aluminium cathode  

SciTech Connect

An electrorefining process in molten chloride salts is being developed at ITU to reprocess the spent nuclear fuel. According to the thermochemical properties of the system, aluminium is the most promising electrode material for the separation of actinides (An) from lanthanides (Ln). The actinides are selectively reduced from the fission products and stabilized by the formation of solid and compact actinide-aluminium alloys with the reactive cathode material. In this work, the maximum loading of aluminium with actinides was investigated by potentiostatic and galvano-static electrorefining of U-Pu- Zr alloys. A very high aluminium capacity was achieved, as the average loading was 1.6 g of U and Pu into 1 g of aluminium and the maximum achieved loading was 2.3 g. For recovery of the actinides from aluminium, a process based on chlorination and a subsequent sublimation of AlCl{sub 3} is proposed. (authors)

Malmbeck, R.; Mendes, E.; Serp, J.; Soucek, P.; Glatz, J.P. [European Commission, JRC, Institute for Transuranium Elements, Postfach 2340, 76125 Karlsruhe (Germany); Cassayre, L. [Laboratoire de Genie Chimique - LGC, Universite Paul Sabatier, UMR 5503, 118 route de Narbonne, 31062 Toulouse Cedex 04 (France)

2007-07-01

184

Bearing characteristics of cast leaded aluminium-silicon alloys  

Microsoft Academic Search

Coefficient of friction characteristics of cast aluminium-silicon alloys varying in lead content from 4 to 16 wt.% have been investigated under lubricated, semi-dry and dry conditions. Under the oil-lubricated test, bearings of all the leaded alloys are able to run without seizure up to the regimes of boundary lubrication and mixed lubrication, whereas the base alloy bearings could not reach

Ashok Sharma; T. V. Rajan

1996-01-01

185

Adhesive wear behaviour of cast aluminium–silicon alloys: Overview  

Microsoft Academic Search

This paper describes the various technological aspects related to adhesive wear of cast aluminium–silicon (Al–Si) alloys. Number of hypothesis and theories proposed in the last two decades in order to explain the different phenomenon related with wear and friction, and influence of test parameters (such as load, sliding speed, counter-surface) and work material properties (like mechanical and metallurgical) on tribological

D. K. Dwivedi

2010-01-01

186

Structure of rapidly solidified aluminium-silicon alloys  

Microsoft Academic Search

This paper present results obtained on rapid solidification of aluminium-silicon alloys from the liquid state. It shows that\\u000a the limit of primary solid solubility is extended almost to the eutectic composition and that the large supersaturation is\\u000a relieved on raising the annealing temperature to the range 110 to 450 C. This conclusion is based on measurements of lattice\\u000a parameter and

S. K. Bose; R. Kumar

1973-01-01

187

Primary Silicon Spherulites in Aluminium-Silicon Alloys  

Microsoft Academic Search

WHEN metallic sodium is added to a eutectic aluminium-silicon alloy, the structure of the eutectic silicon is modified by a mechanism which has been described by several authors1-4. Sodium also modifies the structure of primary silicon crystals in this system, and various workers1,5 have stated that a spheroidal form of silicon can be obtained by this means. Evidence that these

M. G. Day

1968-01-01

188

Melatonin reduces oxidative damage induced by aluminium in rat kidney  

Microsoft Academic Search

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

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

2009-01-01

189

Interfacing the aluminium-air battery with telecommunications equipment  

Microsoft Academic Search

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

P. Hodgson; M. Heath

1990-01-01

190

Mechanical Properties of Particulate Reinforced Aluminium Alloy Matrix Composite  

Microsoft Academic Search

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

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

2011-01-01

191

Low-velocity impact failure of aluminium honeycomb sandwich panels  

Microsoft Academic Search

In this paper, the failure response of aluminium sandwich panels subjected to low-velocity impact is discussed. A three-dimensional geometrically correct finite element model of the honeycomb sandwich plate and a rigid impactor was developed using the commercial software, ABAQUS. This discrete modelling approach enabled further understanding of the parameters affecting the initiation and propagation of impact damage. Strain-hardening behaviour of

C. C. Foo; L. K. Seah; G. B. Chai

2008-01-01

192

Structure and distribution of oxides in aluminium foam  

Microsoft Academic Search

Foaming of aluminium is investigated under oxidizing and non-oxidizing gas atmospheres. Foams were prepared by mixing and pressing Al99.95 and TiH2 powders and foaming the pressed material in a gas-tight X-ray transparent furnace while following the process by X-ray radioscopy. The structure and distribution of the oxides present in the powders, precursors and foams were studied by light microscopy, scanning

Alexander Dudka; Francisco Garcia-Moreno; Nelia Wanderka; John Banhart

2008-01-01

193

Aluminium alloy-solid lubricant talc particle composites  

Microsoft Academic Search

This paper describes the method of synthesizing cast aluminium alloy talc particulate composites and their mechanical and\\u000a wear properties. Talc particles were characterized using X-ray diffraction, infrared spectroscopy and differential thermal\\u000a analysis techniques. Composites with two Al-Si alloys (LM 13 and LM 6) as matrices were prepared by heating the molten alloys\\u000a to 750 C and adding the preheated talc

A. K. Jha; T. K. Dan; S. V. Prasad; P. K. Rohatgi

1986-01-01

194

Abrasive wear behaviour of SiC\\/2014 aluminium composite  

Microsoft Academic Search

Aluminium alloy matrix reinforced with 15wt% SiC particles were prepared by powder metallurgy (PM) method. Wear behaviour of the composite was investigated to find out effects of operating variables and hardness in terms of the Taguchi approach, on a pin-on-disc machine and compared with the previous work on the composite produced by liquid metallurgy method [1]. Analysis of variance (ANOVA)

Yusuf ?ahin

2010-01-01

195

The low-temperature thermopower of Frenkel defects in aluminium  

Microsoft Academic Search

The thermopower S has been measured in the temperature range 1.3-13K (reference: superconductor) on aluminium containing Frenkel defects (FD), i.e. self-interstitials and vacancies of equal concentration c (maximum 850 PPM). The FD have been produced in varying concentration and configuration by reactor irradiation at 15K ('isolated' FD) and subsequent annealing ('agglomerated' FD). A whole such cycle could be made on

G. Sieber; G. Wehr; K. Boning

1977-01-01

196

Hydrothermal crystallization of boehmite from freshly precipitated aluminium hydroxide  

Microsoft Academic Search

Hydrothermal crystallization of boehmite from freshly precipitated aluminium hydroxide was monitored using X-ray powder diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy. Crystallite sizes and interplanar spacings for boehmite samples were determined. Changes in the crystallinity of boehmite influenced the corresponding FT-IR spectra. The maximum specific area for boehmite powder was 246 m2 g?1, as measured by the Brunauer–Emmet–Teller (BET)

? Drag?evi?; S Popovi?

1999-01-01

197

The precipitation of potassium aluminium sulphate from aqueous solution  

NASA Astrophysics Data System (ADS)

A precipitation study has been made with potassium aluminium sulphate (potash alum) produced by mixing aqueous solutions of its constituent salts. Rates of nucleation, as indicated by the induction period, were measured for both agitated and non-agitated solutions over the temperature range 15-35°C. Nucleation rates increase with increases in agitation, temperature and supersaturation, but the latter has the dominant effect, as predicted by classical nucleation theory. The temperature-dependence of the interfacial tension is evaluated.

Mullin, J. W.; Žá?ek, S.

1981-06-01

198

Forming of aluminium alloy at temperatures just below melting point  

Microsoft Academic Search

In order to improve the mechanical properties of products, a forming process of a solid material at a temperature just below the melting point is proposed. The material is deformed at the semi-solid temperature due to the heat generation caused by plastic deformation. The tensile strength, elongation, hardness and toughness of the aluminium alloy (Al–7%Si–0.3%Mg) billet extruded at temperatures between

M Shiomi; D Takano; K Osakada; M Otsu

2003-01-01

199

Growth of eutectic silicon from primary silicon crystals in aluminium-silicon alloys  

SciTech Connect

Technological interest in aluminium-silicon alloys derives, fundamentally, from their excellent moulding properties provided by the presence of silicon. In addition, they possess high thermal and electrical conductivities and good corrosion resistance. The possibility of modification of their cast structure by adding small quantities of alkaline and alkaline-earth elements makes their mechanical characteristics very competitive. Metallographic observations of the structures of primary and eutectic silicon crystals, and their possible synergistic influence, provide useful data on the critical stages of formation and growth of eutectic silicon phase. The nucleation and growth of eutectic silicon, removed from the cooperative precipitation zone, induce refinement in crystal size and, therefore, an improvement of the mechanical properties of the moulded structure. The aim of this investigation was to observe the influence of primary silicon crystals on the nucleation and growth of eutectic silicon.

Criado, A.J.; Martinez, J.A.; Calabres, R. [Complutense Univ. of Madrid (Spain). Dept. of Materials Science and Metallurgical Engineering] [Complutense Univ. of Madrid (Spain). Dept. of Materials Science and Metallurgical Engineering

1997-01-01

200

Laser-induced electrochemical de- and repassivation investigations on plasma-oxidized aluminium alloys  

NASA Astrophysics Data System (ADS)

In situ laser depassivation of plasma electrolytically oxididized (PEO) coatings on aluminium was investigated with nanosecond pulses. Ultraviolet radiation of 266 nm was chosen in order to achieve a high absorption in the dielectric coating. The additive accumulation of laser-induced material defects (incubation) affected the depassivation processes. Incubation occurred only at the edges of the ablation craters irradiated by the outer region of the Gaussian beam profile, where the local fluence is below the ablation threshold. The ablation rate in the spot center did not exhibit an incubation effect. Repassivation was interpreted by a linear combination of a high-field and a point defect growth model. At low overpotentials, field gradients affect the process driving the oxide growth at the buried interface. At high fields, corrosion reactions dominate at the oxide/solution interface.

Nagy, Tristan O.; Pacher, Ulrich; Giesriegl, Ariane; Soyka, Lukas; Trettenhahn, Günter; Kautek, Wolfgang

2014-05-01

201

Theoretical aspects of fluoride air contaminant formation in aluminium smelter potrooms.  

PubMed

The amount of particulate fluorides evolved from aluminium electrolysis cells is not entirely accounted for by the fluorides entrained in the anode gas. The largest additional source of particulate fluoride formation is by direct evaporation of fluorides into the anode gas stream and subsequent condensation on the drops of electrolyte generated in the process of bubble burst. A theoretical model was used for the calculation of the main physical parameters responsible for the formation of particle nuclei when the hot anode-gas is mixed with ambient air. The results of these calculations are in agreement with experimental observations reported in the literature. In particular, the size distribution, composition and morphology of the nano-particles support the theory of a vapour condensation mechanism under conditions of extreme supersaturation, but further studies are necessary. PMID:15877162

L'vov, Boris V; Polzik, Leonid K; Weinbruch, Stephan; Ellingsen, Dag G; Thomassen, Yngvar

2005-05-01

202

Friction stir welding of aluminium lap joint by tool without probe  

Microsoft Academic Search

A friction stir welding process, with a rotating tool without a probe, was employed and applied to a lap joint of aluminium plate. The thickness of the aluminium plates was 0.5 mm. New tool shapes were developed. The tops of the tool were dome shaped. In this process, the rotating tool was plunged into the aluminium plate. The tool-rotating axis was

Kinya Aota; Kenji Ikeuchi

2010-01-01

203

Use of vermicompost extract as an aluminium inhibitor in aqueous solutions  

Microsoft Academic Search

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

D. Alter; A. Mitchell

1992-01-01

204

Improving the corrosion protection of aluminium alloys using reactive magnetron sputtering  

Microsoft Academic Search

Most high strength aluminium alloys used in the aircraft industries are susceptible to corrosion. Up to now hexavalent chromium is the conventional corrosion inhibitor. Because chromium in hexavalent state is carcinogenic, it is necessary to develop effective alternative inhibitor systems. We investigated magnetron sputtered substoichiometric and stoichiometric aluminium nitride (AlNx with x?1) coatings for corrosion protection of aluminium alloys 2024-T3,

H. Schäfer; H.-R. Stock

2005-01-01

205

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

Microsoft Academic Search

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

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

2008-01-01

206

Stock dynamics and emission pathways of the global aluminium cycle  

NASA Astrophysics Data System (ADS)

Climate change mitigation in the materials sector faces a twin challenge: satisfying rapidly rising global demand for materials while significantly curbing greenhouse-gas emissions. Process efficiency improvement and recycling can contribute to reducing emissions per material output; however, long-term material demand and scrap availability for recycling depend fundamentally on the dynamics of societies' stocks of products in use, an issue that has been largely neglected in climate science. Here, we show that aluminium in-use stock patterns set essential boundary conditions for future emission pathways, which has significant implications for mitigation priority setting. If developing countries follow industrialized countries in their aluminium stock patterns, a 50% emission reduction by 2050 below 2000 levels cannot be reached even under very optimistic recycling and technology assumptions. The target can be reached only if future global per-capita aluminium stocks saturate at a level much lower than that in present major industrialized countries. As long as global in-use stocks are growing rapidly, radical new technologies in primary production (for example, inert anode and carbon capture and storage) have the greatest impact in emission reduction; however, their window of opportunity is closing once the stocks begin to saturate and the largest reduction potential shifts to post-consumer scrap recycling.

Liu, Gang; Bangs, Colton E.; Müller, Daniel B.

2013-04-01

207

Modelling of detonation cellular structure in aluminium suspensions  

NASA Astrophysics Data System (ADS)

Heterogeneous detonations involving aluminium suspensions have been studied for many years for industrial safety policies, and for military and propulsion applications. Owing to their weak detonability and to the lack of available experimental results on the detonation cellular structure, numerical simulations provide a convenient way to improve the knowledge of such detonations. One major difficulty arising in numerical study of heterogeneous detonations involving suspensions of aluminium particles in oxidizing atmospheres is the modelling of aluminium combustion. Our previous two-step model provided results on the effect on the detonation cellular structure of particle diameter and characteristic chemical lengths. In this study, a hybrid model is incorporated in the numerical code EFAE, combining both kinetic and diffusion regimes in parallel. This more realistic model provides good agreement with the previous two-step model and confirms the correlations found between the detonation cell width, and particle diameter and characteristic lengths. Moreover, the linear dependence found between the detonation cell width and the induction length remains valid with the hybrid model.

Briand, A.; Veyssiere, B.; Khasainov, B. A.

2010-12-01

208

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

209

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

210

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

211

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

Microsoft Academic Search

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

Anil Kumar; Sachin Maheshwari; Chitra Sharma; Naveen Beri

2011-01-01

212

Light weight cellular structures based on aluminium  

SciTech Connect

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

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

1997-02-01

213

Investigation of the hydration and dehydration of aluminium oxide-hydroxide using high frequency dielectric measurements between 300 kHz3 GHz  

Microsoft Academic Search

Aluminium oxide exists in several forms which on addition of water give a complex range of oxide-hydroxide; boehmite, bayerite and gibbsite. High frequency dielectric measurements {300 kHz-3 GHz} are reported on the hydrated and dehydration of certain of these oxide-hydroxides. The amplitude of the observed dielectric relaxation correlates approximately with the water content, however anomalies can be observed during dehydration

R. A. Pethrick; D. Hayward; K. Jeffrey; S. Affrossman; P. Wilford

1996-01-01

214

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

215

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

216

Effects of silicon content on the mechanical and tribological properties of monotectoid-based zinc–aluminium–silicon alloys  

Microsoft Academic Search

In this work, one binary zinc–aluminium and eight ternary zinc–aluminium–silicon alloys were produced by permanent mould casting. Friction and wear properties of the alloys were investigated in both as-cast and heat-treated conditions using a block-on-ring machine and the results were related to their microstructure and mechanical properties.It was observed that the microstructure of the zinc–aluminium–silicon alloys consisted of aluminium-rich ?,

Temel Sava?kan; Alev Ayd?ner

2004-01-01

217

Microstructural studies of aluminium-silicon alloy reinforced with alumina fibres  

Microsoft Academic Search

The microstructure of an alumina fibre reinforced Al-7wt% Si alloy has been investigated. It was shown that the Al-Si eutectic structure which characterized this alloy was markedly changed by the presence of the fibres, with coarsening of silicon particles and a reduction in primary aluminium grain size. The coarse silicon particles exhibited twinning but no orientation relationship with the aluminium.

Ming Yang; V. D. Scott

1991-01-01

218

Compressibility and structure factors at zero wavevector of liquid aluminium-silicon alloys  

Microsoft Academic Search

A precise 'pulse-echo method' is used to measure the sound velocity in liquid aluminium and aluminium-silicon alloys from the melting point up to 1000 degrees C. The adiabatic compressibility and static structure factors are evaluated. It is found that the compressibility and structure factors display anomalous variations around the eutectic composition.

N. M. Keita; S. Steinemann

1978-01-01

219

Embedded Fibre Bragg Grating Array Sensors in Aluminium Alloy Matrix by Ultrasonic Consolidation  

E-print Network

Embedded Fibre Bragg Grating Array Sensors in Aluminium Alloy Matrix by Ultrasonic Consolidation ABSTRCT Fibre Bragg Grating (FBG) array sensors have been successfully embedded in aluminium alloy matrix sensors have been embedded only in glass and carbon fibre reinforced composite materials and structures

Neirotti, Juan Pablo

220

Dispersoid precipitation and process modelling in zirconium containing commercial aluminium alloys  

Microsoft Academic Search

Small dispersoid particles inhibit recrystallisation and are thus critical in controlling the grain structure of many high strength commercial aluminium alloys. A general, physical model has been developed for the precipitation of Al3Zr dispersoids in aluminium alloys. The predictions of the model have been compared with results of an experimental investigation of Al3Zr precipitation in 7050. The model has been

J. D. Robson; P. B. Prangnell

2001-01-01

221

Tensile behavior of dissimilar friction stir welded joints of aluminium alloys  

Microsoft Academic Search

The heat treatable aluminium alloy AA2024 is used extensively in the aircraft industry because of its high strength to weight ratio and good ductility. The non-heat treatable aluminium alloy AA5083 possesses medium strength and high ductility and used typically in structural applications, marine, and automotive industries. When compared to fusion welding processes, friction stir welding (FSW) process is an emerging

N. Shanmuga Sundaram; N. Murugan

2010-01-01

222

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

Microsoft Academic Search

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

Yasunari Tozaki; Yoshihiko Uematsu; Keiro Tokaji

2007-01-01

223

Process parameters optimization for friction stir welding of RDE40 aluminium alloy using Taguchi technique  

Microsoft Academic Search

Taguchi approach was applied to determine the most influential control factors which will yield better tensile strength of the joints of friction stir welded RDE-40 aluminium alloy. In order to evaluate the effect of process parameters such as tool rotational speed, traverse speed and axial force on tensile strength of friction stir welded RDE-40 aluminium alloy, Taguchi parametric design and

A. K. LAKSHMINARAYANAN; V. BALASUBRAMANIAN

2008-01-01

224

The strength of friction stir welded and friction stir processed aluminium alloys  

Microsoft Academic Search

Local strength of friction stir (FS) welds and FS processed aluminium alloys in heat-treatable aluminium alloys is dominated by precipitation hardening. Strengthening due to stored dislocations is generally limited to 40MPa, and grain size strengthening is generally less than 10MPa. Local crystallographic texture can cause yield strength variation on the order of 5%. Published models for strengthening of FS welds

M. J. Starink; A. Deschamps; S. C. Wang

2008-01-01

225

Some characteristics of friction welded joints between particulate alumina composite material and 6061 aluminium alloy  

Microsoft Academic Search

Friction welded joints were made with 6061 aluminium alloy and aluminium alloy composite material (MMC) containing 16.1% vol. dispersed particulate alumina and the structures and mechanical properties of these joints were examined.For a short friction time the heat affected zone of a joint was formed almost parallel to the weld interface; however, with increasing friction time it became shaped like

K. Katoh; H. Tokisue

1997-01-01

226

Compressive behavior of age hardenable tetrahedral lattice truss structures made from aluminium  

E-print Network

,7]. While both lattice truss and honeycomb core sandwich panels are structurally supe- rior to metal foam perforated 6061 aluminium alloy sheets. Simple air brazing is used to construct sandwich panels with cellular structures out- perform aluminium foams and prismatic corrugations, and compare favorably with honeycombs

Wadley, Haydn

227

Direct complexometric determination of magnesium in the presence of uranium, iron and aluminium.  

PubMed

Conditions for the direct complexometric determination of magnesium in the presence of uranium, iron and aluminium are described. The method is based on the masking of uranium by hydroxylamine, and of iron and aluminium by triethanolamine. Methylthymol Blue is used as indicator for the EDTA titration of magnesium at pH 10. PMID:18960663

Mareska, V

1969-11-01

228

Aluminium oxide film for 2D photonic structure: room temperature formation  

Microsoft Academic Search

We report about aluminium anodic oxide films (AOFs) as self-organising microstructures for photonic band gap (PBG) crystal application. Structural analysis show that aluminium anodic oxide has formed a structure of randomly oriented clusters each of them consisting of neatly ordered submicrometer cells. Measurements show that at room temperature pores of up to 460 nm wide can be formed, thus, opening

I. Mikulskas; S. Juodkazis; A. Jagminas; Š. Meškinis; J. G. Dumas; J. Vaitkus; R. Tomasiunas

2001-01-01

229

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

E-print Network

or automotive components with titanium or titanium alloys inserts [1;2]. When using conventional die casting stress of about 100 MPa. Keywords: Casting; Mechanical Properties Testing; Push-out; Aluminium alloys it is possible to locally enhance stiffness and toughness of classical aluminium castings for aeronautical

Boyer, Edmond

230

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

Microsoft Academic Search

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

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

2006-01-01

231

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

Microsoft Academic Search

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

Gaston Riverin; Jean-François Bilodeau; Claude Dupuis

232

Aluminium phosphate adjuvants prepared by precipitation at constant pH. Part I: composition and structure  

Microsoft Academic Search

Aluminium phosphate adjuvant was precipitated under constant pH conditions in an effort to characterize materials formed at defined precipitation conditions. A reaction vessel was designed to provide a continuous steady-state process. An aqueous solution containing aluminium chloride and sodium dihydrogen phosphate was pumped into the reaction vessel at a constant rate. A second pump infused a sodium hydroxide solution at

Lana S. Burrell; Clifford T. Johnston; Darrell Schulze; Jim Klein; Joe L. White; Stanley L. Hem

2000-01-01

233

Aluminium phosphate potentiates the efficacy of DNA vaccines against Leishmania mexicana  

Microsoft Academic Search

DNA vaccines have been able to induce partial protection against infection with Leishmania in mice, but it is still necessary to increase their efficacy. In the present study we evaluated aluminium phosphate as an adjuvant of different formulations and doses of DNA vaccines against L. mexicana in BALB\\/c mice. Aluminium phosphate had no effect on the humoral response induced by

Miguel Rosado-Vallado; Mirza Mut-Martin; Maria del Rosario García-Miss; Eric Dumonteil

2005-01-01

234

Bioavailability of ketoprofen in man with and without concomitant administration of aluminium phosphate  

Microsoft Academic Search

The purpose of this study was to determine whether a concomitant single dose of antacid (aluminium phosphate), or multiple doses of this antacid, administered prior to and with ketoprofen would alter the bioavailability of this non steroidal anti-inflammatory agent. The possible effects of aluminium phosphate were evaluated following administration of ketoprofen alone (Phase I), co-administration of antacid and ketoprofen (Phase

J. L. Brazier; J. N. Tamisier; D. Ambert; A. Bannier

1981-01-01

235

Extrusion Die Design and Process Simulation of High Strength Aluminium Alloy  

Microsoft Academic Search

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

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

2011-01-01

236

Evaluation Of Four Welding Arc Processes Applied To 6061 Aluminium Alloy  

Microsoft Academic Search

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

A. Benoit; P. Paillard; T. Baudin; S. Jobez; J.-F. Castagné

2011-01-01

237

Ab initio studies of aluminium fluoride surfaces A. Wander,a  

E-print Network

Ab initio studies of aluminium fluoride surfaces A. Wander,a C. L. Bailey,a S. Mukhopadhyay,b B. G as an Advance Article on the web 7th April 2006 DOI: 10.1039/b600273k Solid aluminium fluorides have great fluoride materials. We can also use these results to postulate a mechanism for the observed high reactivity

238

Microstructures and mechanical properties of engineered short fibre reinforced aluminium matrix composites  

Microsoft Academic Search

Aluminium matrix composites have been fabricated by squeeze casting into short fibre preforms modified on the basis of a phase contiguity model to improve mechanical performance. Fibre junctions were created in a planar random alumina fibre array by (a) sintering, (b) phosphoric acid treatment, (c) phosphoric acid\\/aluminium hydroxide (P\\/Al) treatment and (d) infiltration with alumina powder and sintering. The microstructures

H. X. Peng; Z. Fan; D. S. Mudher; J. R. G. Evans

2002-01-01

239

Effect of aluminium sheet surface conditions on feasibility and quality of resistance spot welding  

Microsoft Academic Search

A study investigating the effect of sheet surface condition on resistance spot welding (RSW) of aluminium has been carried out. This concentrates on two automotive aluminium alloys; AA5754 and AA6111, used for structural and closure applications respectively. The results show the marked effect that surface condition can have on the RSW process. For AA5754 sheet incomplete removal of a ‘disrupted

L. Han; M. Thornton; D. Boomer; M. Shergold

2010-01-01

240

Effect of aluminium doping on structural and gas sensing properties of zinc oxide thin films deposited by spray pyrolysis  

Microsoft Academic Search

A facile spray pyrolysis route is used to deposit aluminium doped ZnO (AZO) thin films on to the glass substrates. It is observed that on aluminium doping the particle size of ZnO reduces significantly; moreover, uniformity of particle also gets enhanced. Their XRD study reveals that intensity ratio of crystal planes depend on the aluminium doping concentration. The gas response

Satish S. Badadhe; I. S. Mulla

2011-01-01

241

Corrosion of aluminium in the aqueous chemical environment of a loss-of-coolant accident at a nuclear power plant  

Microsoft Academic Search

Aluminium corrosion is a significant concern in the aqueous chemical environment of the reactor containment building following a hypothetical loss-of-coolant accident (LOCA) at a nuclear power plant. Aluminium corrosion may lead to the formation of precipitates that can, in combination with insulation debris, block the recirculation sump screens. This study investigated aluminium corrosion experimentally at both bench and pilot scale

Dong Chen; Kerry J. Howe; Jack Dallman; Bruce C. Letellier

2008-01-01

242

Investigation of the optical properties of hollow aluminium 'nano-caps'  

NASA Astrophysics Data System (ADS)

A colloidal suspension of hollow aluminium, cap-shaped nanoparticles ('nano-caps') can be conveniently produced by evaporation of aluminium onto a spin-coated layer of polystyrene nanoparticles (PSNPs), followed by sonication and dissolution of the polymer template. Although ordinary spherical aluminium nanoparticles have a plasmon resonance in the ultra-violet, the 'nano-caps' show plasmon absorption between 700 and 1200 nm due to their geometry. The position of their extinction peaks can be tuned by varying the thickness of the aluminium and the shape of the nano-cap. The optical properties of these shapes were modelled using the discrete dipole approximation method, which confirmed that the 'caps' have very significantly red-shifted absorbance and scattering compared to spheres. This finding suggests that aluminium nano-caps might compete with gold and silver nanoparticles in applications requiring absorption in the near infrared.

Liu, J.; Cankurtaran, B.; McCredie, G.; Ford, M. J.; Wieczorek, L.; Cortie, M. B.

2005-12-01

243

Determination of phosphorus in hypereutectic aluminium-silicon alloys.  

PubMed

A reproducible method is described for determination of small amounts of phosphorus (from 0.0005% to 0.02%) in hypereutectic aluminium-silicon complex alloys. The method permits the separate determination of phosphorus in acid-soluble and acid-insoluble fractions. Phosphomolybdate is extracted with n-butanol-chloroform solvent mixture and back-extracted with a btannous chloride reducing solution. The phosphorus content of a sample cut into small pieces decreases during storage; loss of phosphorus is negligible on acid dissolution under oxidizing conditions. PMID:18961077

Mukai, K

1972-04-01

244

Wear behaviour of cast hypereutectic aluminium silicon alloys  

Microsoft Academic Search

In the present paper, influence of alloying elements on wear behaviour of binary (Al–17%Si) and multi-component (Al–17Si–0.8Ni–0.6Mg–1.2Cu–0.6Fe) cast hypereutectic aluminium alloys has been reported. Experimental alloys were prepared via foundry technique. Wear behaviour of Al–17Si and Al–17Si–X {X=Ni, Cu, Mg, Fe} alloys was studied using pin on disc (ASTM: G99) type of friction and wear testing machine. Dry sliding wear

Dheerendra Kumar Dwivedi

2006-01-01

245

Foaming of aluminium-silicon alloy using concentrated solar energy  

SciTech Connect

Solar energy is used for the work reported here as a nonconventional heating system to produce aluminium foam from Al-Si alloy precursors produced by powder metallurgy. A commercial precursor in cylindrical bars enclosed in a stainless-steel mould was heated under concentrated solar radiation in a solar furnace with varied heating conditions (heating rate, time, and temperature). Concentrated solar energy close to 300 W/cm{sup 2} on the mould is high enough to achieve complete foaming after heating for only 200 s. Under these conditions, the density and pore distribution in the foam change depending on the solar heating parameters and mould design. (author)

Cambronero, L.E.G.; Ruiz-Roman, J.M. [Grupo de Materiales Hibridos, ETSIM-UPM, Madrid, Rios Rosas 21, 28003 Madrid (Spain); Canadas, I.; Martinez, D. [Plataforma Solar de Almeria, CIEMAT, P.O. Box 22, 04200 Tabernas (Almeria) (Spain)

2010-06-15

246

Mechanism of aluminium bio-mineralization in the apoferritin cavity  

NASA Astrophysics Data System (ADS)

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

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

2013-08-01

247

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

248

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

249

Aluminium in Cars â Unlocking the Light-Weighting Potential  

NSDL National Science Digital Library

In this brochure, the European Aluminium Association (EAA) evaluates the need for vehicle lightweighting to reduce CO2 emissions. Since the 70âs aluminum has been used for some car components (radiators, cylinder heads, and bumper beams), but now has grown to the average amount of 140 kg per car produced in Europe. Aluminum castings, extrusions, forgings and sheets can now be found nearly everywhere, including in car bodies, closures, chassis, suspensions and wheels. This resource explains why, now more than ever, reducing vehicle mass is necessary and how aluminum can be used to further improve the sustainability and the safety of future generations of cars.

Association, European A.

250

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

Microsoft Academic Search

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

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

2010-01-01

251

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

PubMed

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

Bettinger, C; Zimmermann, H W

1991-01-01

252

Curcumin attenuates aluminium-induced functional neurotoxicity in rats.  

PubMed

Curcumin is a polyphenol extracted from the rhizome of Curcuma longa and well known as a multi-functional drug with antioxidative, anti-cancerous and anti-inflammatory activities. Curcumin's antiaging and neuroprotective potential is widely reported. In the present study, effect of curcumin treatment dose 30 mg kg(-1) day(-1) was investigated against aluminium neurotoxicity in young and old animals. Direct and indirect intakes of aluminium have been reported to be involved in the etiology of several neurodegenerative disorders like Alzheimer's and Parkinson's diseases. Long term Al was administered through drinking water at a dose of 50 mg/kg/day for 6 months in both young (4 months) and old (18 months) male Wistar rats. Result obtained demonstrates that curcumin treatment attenuates the Al-induced alterations at biochemical, behavioral and ultrastructural levels which was well reflected in the electrophysiological recordings. Our results indicate that curcumin's ability to bind redox active metals and cross the blood-brain barrier could be playing crucial role in preventing against Al-induced neurotoxicity. PMID:19376155

Sethi, Pallavi; Jyoti, Amar; Hussain, Ejaz; Sharma, Deepak

2009-07-01

253

Controlling interferometric properties of nanoporous anodic aluminium oxide  

PubMed Central

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. PMID:22280884

2012-01-01

254

Cancellous bone homograft storage with aluminium-polyethylene bags.  

PubMed

In order to transport and cryopreserve human tissues, it is essential to have an easy-to-use recipient where tissues can be kept in sterile conditions. Here we show the results obtained by using Macopharma's tissue freezing bags, an aluminium-polyethylene multilayer bag, in our tissue bank of the Centro Comunitario de Sangre y Tejidos de Asturias. Five hundred and twenty-seven cancellous bone homografts were obtained from hospitals located 120 km around our Bank. The homografts were submitted to bacteriological controls and sent to our bank in these bags. They were stored at -70 degrees C and sent in dry ice to about 50 hospitals, where the tissue was bacteriologically controlled and grafted. Furthermore, the behaviour of these bags at -140 degrees C (vapour nitrogen) or -196 degrees C (liquid nitrogen) was tested. Our results indicate that Macopharma aluminium-polyethylene bags are suitable for the transporting and cryopreserving of cancellous bone homografts. These bags could also be used for keeping tissues in nitrogen containers. PMID:16933042

Meana, A; Martinez, R; Cañal, P; Arriaga, M J; Román, F San; Llames, S; Orós, C; Moreno, A; Fernandez, C

2006-01-01

255

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

NASA Astrophysics Data System (ADS)

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

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

2013-10-01

256

A comparison of the mechanical behaviour of self-piercing riveted and resistance spot welded aluminium sheets for the automotive industry  

Microsoft Academic Search

The increased application of lightweight materials, such as aluminium has initiated many investigations into new joining techniques for aluminium alloys. The resistance spot welding (RSW) concept for aluminium has always attracted many researchers from different organizations. Self-piercing riveting (SPR) is the major production process used to join aluminium sheet body structures for the automotive industry. The research team at the

L. Han; M. Thornton; M. Shergold

2010-01-01

257

Chronic exposure to aluminium impairs the glutamate-nitric oxide-cyclic GMP pathway in the rat in vivo.  

PubMed

Aluminium is neurotoxic and is considered a possible etiologic factor in Alzheimer's disease, dialysis syndrome and other neurological disorders. The molecular mechanism of aluminium-induced impairment of neurological functions remains unclear. We showed that aluminium impairs the glutamate-nitric oxide-cGMP pathway in cultured neurons. The aim of this work was to assess by in vivo brain microdialysis whether chronic administration of aluminium in the drinking water (2.5% aluminium sulfate) also impairs the glutamate-nitric oxide-cGMP pathway in the cerebellum of rats in vivo. Chronic exposure to aluminium reduced NMDA-induced increase of extracellular cGMP by ca 50%. The increase in extracellular cGMP induced by the nitric oxide generating agent S-nitroso-N-acetylpenicillamine was higher (240%) in rats treated with aluminium than in controls. Immunoblotting experiments showed that aluminium reduced the cerebellar content of calmodulin and nitric oxide synthase by 34 and 15%, respectively. Basal activity of soluble guanylate cyclase was decreased by 66% in aluminium-treated rats, while the activity after stimulation with S-nitroso-N-acetylpenicillamine was similar to controls. Basal cGMP in the cerebellar extracellular space was decreased by 50% in aluminium-treated rats. These results indicate that chronic exposure to aluminium reduces the basal activity of guanylate cyclase and impairs the glutamate-nitric oxide-cGMP pathway in the animal in vivo. PMID:10355491

Hermenegildo, C; Sáez, R; Minoia, C; Manzo, L; Felipo, V

1999-03-01

258

Influence of Nano Aluminium Powder Produced by Wire Explosion Process at Different Ambience on Hydrogen Generation  

NASA Astrophysics Data System (ADS)

Nano-aluminium particles are produced through the wire explosion process in different gas medium. The particles produced by wire explosion process, in helium medium are of smaller size compared to argon/nitrogen medium. The nano aluminium powder on reaction with water forms oxides having bayerite and boehmite structure. It is observed that nano aluminium on reaction with KOH solution at room temperature it forms bayerite. The results of the study were confirmed through Wide Angle X-ray diffraction (WAXD) and by Transmission Electron Microscope (TEM) studies. The reaction of nano aluminium powder with KOH solution/water indicates that the rate of hydrogen generation is high when nano aluminium powder reacts with KOH solution than with water. The rate of hydrogen generation gets reduced drastically when the nano aluminium powder which is exposed to air medium for some period is used for reaction with KOH/water. It is also observed that the rate of hydrogen generation is high with nano size aluminium particles compared with ultrafine particles.

Sarathi, Ramanujam; Sankar, Binu; Chakravarthy, Satyanarayanan R.

2010-07-01

259

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

260

Effects on the nervous system among welders exposed to aluminium and manganese.  

PubMed Central

OBJECTIVES--The purpose was to study the effects on the nervous system in welders exposed to aluminium and manganese. METHODS--The investigation included questionnaires on symptoms, psychological methods (simple reaction time, finger tapping speed and endurance, digit span, vocabulary, tracking, symbol digit, cylinders, olfactory threshold, Luria-Nebraska motor scale), neurophysiological methods (electroencephalography, event related auditory evoked potential (P-300), brainstem auditory evoked potential, and diadochokinesometry) and assessments of blood and urine concentrations of metals (aluminium, lead, and manganese). RESULTS--The welders exposed to aluminium (n = 38) reported more symptoms from the central nervous system than the control group (n = 39). They also had a decreased motor function in five tests. The effect was dose related in two of these five tests. The median exposure of aluminium welders was 7065 hours and they had about seven times higher concentrations of aluminium in urine than the controls. The welders exposed to manganese (n = 12) had a decreased motor function in five tests. An increased latency of event related auditory evoked potential was also found in this group. The median manganese exposure was 270 hours. These welders did not have higher concentrations of manganese in blood than the controls. CONCLUSIONS--The neurotoxic effects found in the groups of welders exposed to aluminium and manganese are probably caused by the aluminium and manganese exposure, respectively. These effects indicate a need for improvements in the work environments of these welders. PMID:8563855

Sjögren, B; Iregren, A; Frech, W; Hagman, M; Johansson, L; Tesarz, M; Wennberg, A

1996-01-01

261

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

Microsoft Academic Search

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

Anil Kumar; Sachin Maheshwari; Chitra Sharma; Naveen Beri

2011-01-01

262

Effect of magnesium on strength and microstructure of Aluminium Copper Magnesium Alloy  

E-print Network

Abstract: Cast Al – Cu- Mg alloys have w idely used in aircraft, aerospace, ships and boat making, industrial and architectural applications for their good mechanical properties, high strength-to-weight ratio. An intensive study of these cast aluminium family has been found in the literature in terms of enhancing the mechanical properties. The objective of this paper was to investigate the influence of magnesium on microstrructural changes and mechanical properties such as tensile strength and hardness of the Al4Cu alloys. The modifications of Al4Cu by adding Mg of 0.5 to 2 % in the interval of 0.5 % mixing w ith stirrer and casted by gravity die casting, subsequently the specimens w ere subjected T6 type heat treatment for 5 hr at 175?C. The effect of Mg and ageing on microstructure was studied by using optical microscope w ith image analysis software for measuring grain size and dendrite arm spacing. The mechanical properties such as tensile strength and hardness were studied using universal testing machine and Brinell hardness tester respectively. The micro-structural analysis result shows the 2 % addition of Mg reduces the 20 % grain size and 21.52 % dendrite structure. The tensile strength and hardness increasing with % of Mg. The addition of 2 % Mg increases tensile strength 57.9 % and hardness of 25%. Aging specimens showed that 1 % of Mg influence more on grain refinement and mechanical properties due to smaller the grain size.

unknown authors

263

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

264

Nano-sized layered aluminium or zinc-manganese oxides as efficient water oxidizing catalysts.  

PubMed

Nano-sized layered aluminium or zinc-manganese oxides were synthesized and characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction spectrometry, dynamic light scattering and atomic absorption spectroscopy. These oxides showed efficient water oxidizing activity in the presence of cerium(IV) ammonium nitrate as a non-oxo transfer oxidant. Amounts of dissolved manganese, zinc or aluminium, and water oxidation activities of these oxides were reported and compared with other manganese oxides. A mechanism for oxygen evolution and possible roles for zinc or aluminium ions are also proposed. PMID:22565665

Najafpour, Mohammad Mahdi; Pashaei, Babak; Nayeri, Sara

2012-06-21

265

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

266

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 ...

Hayes, Ms.

2011-04-07

267

Interaction of mucus with freshly neutralised aluminium in freshwater.  

PubMed

This study examined the interaction of mollusc trail mucus, and its biochemical constituents, with environmentally relevant concentrations of freshly neutralised aluminium (Al) in freshwater. Upon neutralisation Al starts to polymerise. In the presence of mucus the metal is rapidly localised into the hydrated mucus gel resulting in a likely reduction of its overall degree of polymerisation. A simple Al binding assay identified large-M(r) glycoconjugates as major Al-complexing molecules in mucus. Subsequent isolation and purification of these mucus glycoconjugates showed the metal readily bound to the carbohydrate portion and, in particular, to acidic components such as those containing carboxyl functionality. It is suggested gel-forming extracellular glycoconjugates play a crucial role in preventing the diffusion of Al into biological systems and thus serve to maintain metabolic homeostasis. PMID:12230983

Ballance, Simon; Sheehan, John K; Tkachenko, Andriy; McCrohan, Catherine R; White, Keith N

2002-09-30

268

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

269

Mechanism of high strain rate superplasticity in aluminium alloy composites  

SciTech Connect

A constitutive equation has been obtained through an analysis of high strain rate superplasticity (HSRS) data on a 2124 Al-Si{sub 3}-N{sub 4} 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{sup {minus}1} and an inverse grain size and reinforcement size dependence. It is suggested that the mechanism of HSRS in composites is interface controlled superplasticity. This is depicted on a new superplasticity mechanism map for composites. The map can be used as a guideline for designing composites for optimum superplasticity.

Mishra, R.S.; Mukherjee, A.K. [Univ. of California, Davis, CA (United States). Dept. of Chemical Engineering and Materials Science] [Univ. of California, Davis, CA (United States). Dept. of Chemical Engineering and Materials Science; Bieler, T.R. [Michigan State Univ., East Lansing, MI (United States). Dept. of Materials Science and Mechanics] [Michigan State Univ., East Lansing, MI (United States). Dept. of Materials Science and Mechanics

1997-02-01

270

Aluminium segregation of TiAl during single crystal growth  

SciTech Connect

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

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

1997-09-15

271

Pico- and nanosecond laser ablation of mixed tungsten / aluminium films  

E-print Network

In order to extend the investigation of laser-assisted cleaning of ITER-relevant first mirror materials to the picosecond regime, a commercial laser system delivering 10 picosecond pulses at 355 nm at a frequency of up to 1 MHz has been used to investigate the ablation of mixed aluminium (oxide) / tungsten (oxide) layers deposited on poly- and nanocrystalline molybdenum as well as nanocrystalline rhodium mirrors. Characterization before and after cleaning using scanning electron microscopy (SEM) and spectrophotometry shows heavy dust formation, resulting in a degradation of the reflectivity. Cleaning using a 5 nanosecond pulses at 350 and 532 nm, on the other hand, proved very promising. The structure of the film remnants suggests that in this case buckling was the underlying removal mechanism rather than ablation. Repeated coating and cleaning using nanosecond pulses is demonstrated.

Wisse, M; Steiner, R; Mathys, D; Stumpp, A; Joanny, M; Travere, J M; Meyer, E

2014-01-01

272

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

273

Volume dependence of the melting temperature for aluminium  

NASA Astrophysics Data System (ADS)

We present a simple and straightforward relationship for evaluating the volume dependence of melting temperature based on the Lindemann's melting equation (F.A. Lindemann, Z. Phys. 11 (1910) 609) and the Al'tshular et al. model for the volume dependence of the Gruneisen parameter (L.V. Al'tshuler, S.E. Brusnikin, E.A. Kuz' menkov, J. Appl. Mech. Tech. Phys. 28 (1987) 129). The formula for the volume dependence of melting temperature obtained in the present study has been used to determine the results for aluminium up to a pressure range of 77 GPa. The results obtained for the melting temperature present a good agreement with the available experimental data.

Sharma, S. K.; Sharma, B. K.

2010-08-01

274

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.

Scapecchi, Judith

2012-07-31

275

Non-aqueous aluminium-air battery based on ionic liquid electrolyte  

NASA Astrophysics Data System (ADS)

A promising metal-air secondary battery based on aluminium-oxygen couple is described. In this paper, we observed that an aluminium-air battery employing EMImCl, AlCl3 room temperature ionic liquid (RTIL) as electrolyte and aluminium as negative electrode, has an exceptional reduced self-discharged rate. Due to its new and innovative type of electrolyte, this aluminium-air battery can support relatively high current densities (up to 0.6 mA cm-2) and an average voltage of 0.6-0.8 V. Such batteries may find immediate applications, as they can provide an internal, built-in autonomous and self-sustained energy source.

Revel, Renaud; Audichon, Thomas; Gonzalez, Serge

2014-12-01

276

EBSD study of the microstructure evolution in a commercially pure aluminium severely deformed by ECAP  

NASA Astrophysics Data System (ADS)

Equal channel angular pressing (ECAP) is a promising technique for production of ultrafine-grain materials of a few hundred nanometres size. In the present paper commercially pure aluminium billets were processed by ECAP up to 8 passes using the route BC in which the samples were rotated about the longitudinal axis by 90° in the same direction after each consecutive pressing. Electron backscattered diffraction (EBSD) was used to evaluate the microstructure of the aluminium. EBSD scans revealed a fairly homogeneous ultrafine grained microstructure after 8 passes. This analysis also showed that the fraction of high angle grain boundaries and average grain size were about 70 % and 1500 nm, respectively. Then, tensile properties of the aluminium billets were evaluated. The results represent that the yield stress of aluminium is increased significantly by about four times after application of four consecutive passes of ECAP and then it remains approximately constant.

Tolaminejad, B.; Brisset, F.; Baudin, T.

2012-03-01

277

Aluminium Phosphate as Precipitant of Agglutinable and Non-Agglutinable Strains of H. pertussis  

Microsoft Academic Search

ALUMINA (hydrated aluminium oxide) is generally used to precipitate H. pertussis organisms from aqueous suspensions. With this adsorbent the preparation of alum-precipitated vaccines has never involved any difficulty in getting all the bacteria precipitated.

J. Ungar; P. Muggleton

1948-01-01

278

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

279

Solidification mechanisms of unmodified and strontium-modified hypereutectic aluminium–silicon alloys  

Microsoft Academic Search

The effects of strontium on the solidification mode of hypereutectic aluminium–silicon alloys have been studied. Samples were prepared from an aluminium–17?wt% silicon-based alloy and strontium was added at several different concentrations. The development of the microstructure was investigated by cooling curve analysis, interrupted solidification experiments and optical and scanning electron microscopy. It was found that nucleation of primary silicon is

K. Nogita; S. D. McDonald; A. K. Dahle

2004-01-01

280

Grain size and porosity of cast hypoeutectic aluminium-silicon alloys in hexachloroethane coated mould  

Microsoft Academic Search

This paper examined the effect of concentration of hexachloroethane (C2Cl6) in alumina mould wash on the grain size and apparent porosity of cast hypoeutectic aluminium silicon alloy. A hypoeutectic\\u000a aluminium-silicon alloy was prepared and cast in metal mould coated with alumina slurry to which varied concentrations (0–40\\u000a wt %) of volatile organic compound, C2Cl6, have been added. The effects of

S. A. Ibitoye; M. D. Shittu; J. O. Olawale

2010-01-01

281

Solidification mechanisms of unmodified and strontium-modified hypereutectic aluminium-silicon alloys  

Microsoft Academic Search

The effects of strontium on the solidification mode of hypereutectic aluminium-silicon alloys have been studied. Samples were prepared from an aluminium-17 wt% silicon-based alloy and strontium was added at several different concentrations. The development of the microstructure was investigated by cooling curve analysis, interrupted solidification experiments and optical and scanning electron microscopy. It was found that nucleation of primary silicon

K. Nogita; S. D. McDonald; A. K. Dahle

2004-01-01

282

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

283

Structure and morphology of aluminium doped Zinc-oxide layers prepared by atomic layer deposition  

Microsoft Academic Search

The aim of this work is to study the effects of deposition temperature and aluminium incorporation on the crystalline properties, orientation and grain size of atomic layer deposited ZnO layers. X-ray diffraction analysis revealed a change in the dominant crystallite orientation with increasing substrate temperature. The most perfect crystal structure and largest grain size was found at 2at.% aluminium content.

Zs. Baji; Z. Lábadi; Z. E. Horváth; I. Bársony

284

Modelling of a rotary kiln for the pyrolysis of aluminium waste  

Microsoft Academic Search

This paper deals with the mathematical modelling of a rotary kiln, which is used for the recycling of aluminium waste. This model is mainly based on the coupling between•“a bed model” describing the processes occurring within the bed of aluminium waste flowing inside the kiln,•“a kiln model” describing heat transfer within the kiln itself,•“a gas model” describing processes occurring within

F. Marias; H. Roustan; A. Pichat

2005-01-01

285

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

286

Laser assisted Friction Stir Welding of drawable steel-aluminium tailored hybrids  

Microsoft Academic Search

Steel aluminium Tailor Welded Hybrids are still mentioned to be difficult to be joint as intermetallic phases appear during\\u000a melting welding techniques. These phases are the reason for failure of the joint during loading or forming. As conventional\\u000a friction stir welding, a solid phase welding technology, is not feasible to join steel and aluminium, laser assistance for\\u000a preheating the steel

M. Merklein; A. Giera

2008-01-01

287

Fatigue properties of friction stir welded particulate reinforced aluminium matrix composites  

Microsoft Academic Search

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

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

2010-01-01

288

Predicting tensile strength of friction stir welded AA6061 aluminium alloy joints by a mathematical model  

Microsoft Academic Search

AA6061 aluminium alloy (Al–Mg–Si alloy) has gathered wide acceptance in the fabrication of light weight structures requiring a high strength-to weight ratio and good corrosion resistance. Compared to the fusion welding processes that are routinely used for joining structural aluminium alloys, friction stir welding (FSW) process is an emerging solid state joining process in which the material that is being

K. Elangovan; V. Balasubramanian; S. Babu

2009-01-01

289

Impact energy absorption of aluminium foam fitted AISI 304L stainless steel tube  

Microsoft Academic Search

Closed cell aluminium foam fitted AISI 304L stainless steel tube was investigated for its impact energy absorption characteristics. Quasi-static load–deflection tests were employed to establish the foam–tube interaction factor. Drop experiments were carried out using a free flight drop tower on aluminium foam fitted stainless steel tube to obtain the acceleration–time history of the hammer. Estimated deflections compared well with

R. Rajendran; K. Prem Sai; B. Chandrasekar; A. Gokhale; S. Basu

2009-01-01

290

Recovery of fluoride values from spent pot-lining: Precipitation of an aluminium hydroxyfluoride hydrate product  

Microsoft Academic Search

Treatment of spent pot-lining (SPL) from aluminium smelting cells by a two-stage leaching scheme comprising a water wash and an Al3+ leach and fluoride recovery as an aluminium hydroxyfluoride product has been studied for extraction of fluoride and then recovery as smelter grade AlF3. The NaF content of a ?1.18mm size fraction was removed by the water wash, while the

Diego Fernández Lisbona; Karen M. Steel

2008-01-01

291

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

292

Pulmonary disease from occupational exposure to an artificial aluminium silicate used for cat litter  

Microsoft Academic Search

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

A W Musk; H W Greville; A E Tribe

1980-01-01

293

Simulation and Characterization of Aluminium Three-Dimensional Resonator for Quantum Computation  

NASA Astrophysics Data System (ADS)

We present the simulation and characterization of several aluminium three-dimensional (3D) resonators, which can be used for superconducting quantum computation. By changing the conductivity of the aluminium in a high frequency structure simulator, the loaded quality factor at room temperature and base temperature (20mK) can be simulated. From S21 measurement, we can characterize the properties of the resonators. The simulated and experimental results can be fitted well by exponential equations.

Zhao, Hu; Li, Tie-Fu; Liu, Qi-Chun; Liu, Jian-She; Chen, Wei

2014-10-01

294

Hot deformation and wear resistance of P\\/M aluminium metal matrix composites  

Microsoft Academic Search

Hot compression and wear resistance as well as hardness of powder metallurgy (P\\/M) aluminium metal matrix composites (MMC) were investigated. Metal matrix composites were manufactured using powder metallurgy technique of ball milled mixing in a high energy attritor and cold compaction followed by hot extrusion at 500°C. Matrix of pure aluminium was used to which different weight fractions of Al2O3

G. Abouelmagd

2004-01-01

295

The low velocity impact response of an aluminium honeycomb sandwich structure  

Microsoft Academic Search

The low velocity impact response of two aluminium honeycomb sandwich structures has been investigated by conducting drop-weight impact tests using an instrumented falling-weight impact tower. Initially, the rate-sensitivity of the glass fibre reinforced\\/epoxy skins and aluminium core was investigated through a series of flexure, shear and indentation tests. Here, it was found that the flexural modulus of the composite skins

W. J. Cantwell

2003-01-01

296

Influence of inhibitors on corrosion and anodic behaviour of different grades of aluminium in alkaline media  

NASA Astrophysics Data System (ADS)

The electrochemical properties of different grades of aluminium are said to be dependent on the presence of minor amounts of iron and silicon impurities. This investigation aims mainly at addressing the influence of different inhibitors (e.g., sodium stannate, sodium citrate and calcium oxide combinations) on properties such as corrosion, anodic behaviour and anode utilization efficiency of different grades of aluminium in alkaline media.

Gnana Sahaya Rosilda, L.; Ganesan, M.; Anbu Kulandainathan, M.; Kapali, V.

297

Removal of various pollutants from wastewater by electrocoagulation using iron and aluminium electrode  

Microsoft Academic Search

The present study deals with removal of various pollutants from a real wastewater by electrocoagulation treatment. Combined wastewater from one of the Delhi industrial areas was collected and treated by electrocoagulation process using iron and aluminium electrodes. Removal of Cr, Zn, Ni and Cu were achieved up to 100, 98.71, 69.22 and 48.08% respectively using aluminium electrode while Cr, Cu,

Asheesh Kumar Yadav; Lakhvinder Singh; Ayusman Mohanty; Santosh Satya; T. R. Sreekrishnan

2012-01-01

298

Characterization of aluminium surfaces with and without plasma nitriding by X-ray photoelectron spectroscopy  

Microsoft Academic Search

Substrates of aluminium alloy 2011 have been plasma nitrided using an inductively coupled plasma source and then characterised by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The XRD analysis confirmed the presence of a crystalline aluminium nitride (AlN) layer on the substrates surfaces. Both AlN and Al2O3 were observed by XPS on the surface of the nitrided Al substrates.

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

2001-01-01

299

Increased immunogenicity of recombinant Ad35-based malaria vaccine through formulation with aluminium phosphate adjuvant  

Microsoft Academic Search

Previously, we have shown the potency of recombinant Adenovirus serotype 35 viral vaccines (rAd35) to induce strong immune response against the circumsporozoite protein (CS) of the plasmodium parasite. To further optimize immunogenicity of Ad35-based malaria vaccines we formulated rAd35.CS vaccine with aluminium phosphate adjuvant (AlPO4). In contrast to the conventional protein based vaccines no absorption to aluminium adjuvant was observed

Olga J. A. E. Ophorst; Katarina Radoševi?; Jaco M. Klap; Jeroen Sijtsma; Gert Gillissen; Ratna Mintardjo; Mark J. M. van Ooij; Lennart Holterman; Arjen Companjen; Jaap Goudsmit; Menzo J. E. Havenga

2007-01-01

300

Indirect Amperometric Detection of Aluminium by Flow Injection Analysis Using DASA as Ligand  

Microsoft Academic Search

The analytical technique for aluminium was based upon the complexation reaction between aluminium (Al) and a ligand 1,2?dihydroxy?anthraquinone?3?sulfonic acid (DASA). The system consists of a commercial electrochemical analyzer, flow injection components (manifold, pumps, and valves), and an in?house designed control system to perform automated analysis. Good linearity was observed for Al standards within a range (0 to 1.6 mg\\/L) that was

Shaun D. Thomas; David E. Davey; Dennis E. Mulcahy; Christopher W. K. Chow

2005-01-01

301

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

302

Bioaccumulation of aluminium in the freshwater snail Lymnaea stagnalis at neutral pH  

Microsoft Academic Search

This study examined the accumulation of aluminium (Al) by the freshwater snail Lymnaea stagnalis at neutral pH, when most Al would be predicted to be in an insoluble form (Al(OH)3). Snails were exposed to a range of Al concentrations (38–285 ?g l?1) for 30 days, followed by 20 days in clean water. Aluminium was measured using atomic absorption spectroscopy.Significant accumulation

R. Elangovan; K. N. White; C. R. McCrohan

1997-01-01

303

Activated carbons modified with aluminium–zirconium polycations as adsorbents for ammonia  

Microsoft Academic Search

Microporous\\/mesoporous wood-based activated carbon was modified by impregnation with aluminium–zirconium oxycations and calcined at 300°C, and then used as an adsorbent of ammonia. Water was present either on the carbon or in the gas phase. The initial (before ammonia adsorption) and exhausted materials were characterized using adsorption of nitrogen, potentiometric titration, XRD, FTIR and thermal analysis. Aluminium–zirconium polycations improve ammonia

Camille Petit; Teresa J. Bandosz

2008-01-01

304

Crack resistance of aluminium composite under shock loading at different temperatures  

Microsoft Academic Search

The paper presents the technique of study of aluminium composite K_1d crack resistance at shock loading at T=-50div +300 ^circC. The technique is based on application of split Hopkinson bars and plane specimen for axial wedging. Heating of specimens was carried out by electric heater, cooling -- by vapours of liquid nitrogen. Specimens from aluminium composite A 359 (20 vol.

S. A. Novikov; V. A. Pushkov; V. A. Sinitsyn; G. T. Gray III

1997-01-01

305

Phenomenon of strain hardening behaviour of sintered aluminium preforms during cold axial forming  

Microsoft Academic Search

Cold upsetting experiments were carried out on sintered aluminium preforms in order to evaluate their work-hardening characteristics. Aluminium powder preforms of 92% of theoretical density, with three initial aspect ratios were prepared using a suitable die-set assembly on a 1.0MN capacity hydraulic testing machine. Sintering was carried out in an electric muffle furnace for a period of 1 hour at

N Selvakumar; R Narayanasamy

2003-01-01

306

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

307

Toxicity of acid aluminium-rich water to seven freshwater fish species: a comparative laboratory study.  

PubMed

The present study focuses on the relative sensitivity among freshwater fish species to aqueous aluminium. Seven common Scandinavian fish species were exposed to acidic Al-rich water, acidic Al-poor water, and approximately neutral water as a control. The relative sensitivity among the species to an acute aluminium challenge was documented, and was in the following order: Atlantic salmon, Salmo salar, as the most sensitive; then roach, Rutilus rutilus; minnow, Phoxinus phoxinus; perch, Perca fluviatilis; grayling, Thymallus thymallus; brown trout, Salmo trutta; and Arctic char, Salvelinus alpinus. Substantial mortality was observed in all species when exposed to the Al-rich medium. Some mortality was also observed in minnow, roach, and brown trout exposed to the acidic Al-poor medium and the control medium. A high resistance to aluminium was observed in Arctic char, while perch was found to be more sensitive to aluminium than expected and, for the first time, a toxic response to aqueous aluminium in grayling was documented. Through controlled experimental studies, the results confirm that aluminium is an important factor in the toxicity of acidified waters to freshwater fish species. PMID:15093412

Poléo, A B; ØStbye, K; Øxnevad, S A; Andersen, R A; Heibo, E; Vøllestad, L A

1997-01-01

308

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

309

Investigation on Tool Wear Rate for Modified and Unmodified Aluminium-Silicon Casting Alloy  

NASA Astrophysics Data System (ADS)

This study demonstrates and explains the effect of strontium modification on machinability of aluminium-silicon eutectic (LM-6 type) alloy. This alloy is known to have many favourable features including weight to strength ratio, high corrosion resistance and excellent castability. However, normal unmodified LM-6 alloy has poor machinability, which reduces its applications range. In this work, various samples of LM-6 alloy were cast using sand and metallic chill mould with and without strontium addition. Machining on each cast product, was carried out using recommended cutting parameters for Al-Si alloys. Strontium modified samples have recorded a reduction in average flank wear, an increase in shear plane angles and a reduction in chip thickness. The main reason for this improvement is the refining effect of strontium, which reduces the size of the hard silicon particles. As a result, their abrasive action on the tool face has reduced a lot. Dramatic reductions in tool wear rate were recorded when the microstructures were refined. On the other hand, when no refinement of microstructure occurs, tool wear rate becomes high. Chip analysis showed that strontium modified sample produced a thinner chip thickness with a larger shear plane angle, requiring less cutting forces. The tool wear depends not only on the phases present in the work material, but also on their sizes and distribution over entire structure. Thus, strontium modification has better effect on machinability of die cast alloy compared to that of the sand cast LM-6 alloy.

Haque, M. M.; Khan, A. A.; Ismail, Ahmad F.

310

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

PubMed

To assess the risk of aluminium (Al) toxicity during the restoration of the eutrophic lake Tiefwarensee by hypolimnetic addition of NaAl(OH)(4)-solution (aluminate) the generally limnological monitoring was accompanied by fractionation of Al in water and using Al accumulation on fish gills as bioindicator. The concentration of reactive Al species in the alkaline water (pH 8) peaked at 2mgL(-1) in parts of the anoxic hypolimnion and was 0.088+/-0.053mgL(-1) (n=70) in the epilimnion during the five years of treatment. During an Al treatment cycle in summer 2003, perches showed significant Al accumulation on gills (100microg Al g(-1) dw) whereas roaches, breams and silver carps remained unaffected. Thus, the Al toxicity towards several fish species seems to be low, although the concentration of reactive Al in the lake water increased by a factor of 2. However, high Al toxicity due to lake treatment with aluminate could not be excluded, as high Al-gill concentration was observed. An Al balance two years after the treatment indicates complete export of the added Al into the sediment. PMID:20547414

Wauer, Gerlinde; Teien, Hans-Christian

2010-09-01

311

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

312

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

PubMed

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. PMID:24258012

Chen, Chia-Yun; Wong, Ching-Ping

2014-01-21

313

Deep surface rolling for fatigue life enhancement of laser clad aircraft aluminium alloy  

NASA Astrophysics Data System (ADS)

Deep surface rolling can introduce deep compressive residual stresses into the surface of aircraft metallic structure to extend its fatigue life. To develop cost-effective aircraft structural repair technologies such as laser cladding, deep surface rolling was considered as an advanced post-repair surface enhancement technology. In this study, aluminium alloy 7075-T651 specimens with a blend-out region were first repaired using laser cladding technology. The surface of the laser cladding region was then treated by deep surface rolling. Fatigue testing was subsequently conducted for the laser clad, deep surface rolled and post-heat treated laser clad specimens. It was found that deep surface rolling can significantly improve the fatigue life in comparison with the laser clad baseline repair. In addition, three dimensional residual stresses were measured using neutron diffraction techniques. The results demonstrate that beneficial compressive residual stresses induced by deep surface rolling can reach considerable depths (more than 1.0 mm) below the laser clad surface.

Zhuang, W.; Liu, Q.; Djugum, R.; Sharp, P. K.; Paradowska, A.

2014-11-01

314

Damage of Aluminium Matrix Composite reinforced with Iron Oxide (Fe3O4): Experimental and Numerical Study  

NASA Astrophysics Data System (ADS)

The powder metallurgy components are being widely used for sophisticated industrial applications at a very high rate production and low cost. In modern industry, more and more it is imposed to develop new composites, such as high resistant, low density, alternative materials in order to realise multifunctional pieces. For this reason, it is very striking to use reinforced (Fe3O4-iron oxide) aluminium matrix composites in structural applications (automotive, aeronautical, etc.) due to their outstanding stiffness-to-weight and strength-to-weight ratios. These materials show good thermal conductivity and wear resistance and also low thermal expansion, all of which makes them very high multifunctional light weight materials. Additionally, it is very attractive way to add Fe3O4-iron oxide reinforcing for improving the magnetic permeability of this composites and by this way, it can be obtained a good synchronization between thermal and electrical conductivities and magnetic permeability.

Ayari, F.; Katundi, D.; Bayraktar, E.

2011-01-01

315

Interactive effects of aluminium and phosphorus on microbial leaf litter processing in acidified streams: a microcosm approach.  

PubMed

Decline in pH, elevated aluminium (Al) concentrations, and base cations depletion often covary in acidified headwater streams. These parameters are considered as the main factors reducing microbial activities involved in detritus processing, but their individual and interactive effects are still unclear. In addition to its direct toxicity, Al can also reduce the bioavailability of phosphorus (P) in ecosystems through the formation of stable chemical complexes. A three week microcosm experiment was carried out in acid conditions to assess the interactive effects of Al (three levels: 0, 200, and 1,000 ?g L(-1)) and P (25, 100, and 1,000 ?g L(-1)) on alder leaf litter processing by an aquatic hyphomycete consortium. Our results showed that Al alone reduced fungal growth and altered fungal decomposer activities. High P levels, probably through an alleviation of Al-induced P limitation and a reduction of Al toxic forms, suppressed the negative effects of Al on detritus decomposition. PMID:24361567

Clivot, Hugues; Charmasson, Faustine; Felten, Vincent; Boudot, Jean-Pierre; Guérold, François; Danger, Michael

2014-03-01

316

Friction stir welding of titanium alloy TiAl6V4 to aluminium alloy AA2024-T3  

Microsoft Academic Search

Titanium alloy TiAl6V4 and aluminium alloy 2024-T3 were successfully joined by friction stir welding. Microstructure, hardness and tensile strength of the butt joint were investigated. The weld nugget exhibits a mixture of fine recrystallized grains of aluminium alloy and titanium particles. Hardness profile reveals a sharp decrease at titanium\\/aluminium interface and evidence of microstructural changes due to welding on the

Ulrike Dressler; Gerhard Biallas; Ulises Alfaro Mercado

2009-01-01

317

Crystallization of aluminium hydroxide from the reactive NaAl(OH) 4–NaHCO 3 solution: Experiment and modeling  

Microsoft Academic Search

The crystallization kinetics of aluminium hydroxide from the sodium aluminate solution reacted with sodium bicarbonate were systematically investigated in a steady-state MSMPR (mixed-suspension mixed-product removal) crystallizer for the first time, and the expressions of the nucleation rate, growth rate and the agglomeration kernel of aluminium hydroxide were successfully regressed. The aluminium hydroxide particles precipitated from the reactive system are identified

Yan Li; Yifei Zhang; Chao Yang; Libin Chen; Yi Zhang

2010-01-01

318

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

319

Vector Addition Calculator  

NSDL National Science Digital Library

The Vector Addition Calculator lets students add vectors graphically in 2 dimensions by dragging the tips of the vectors. The results of a component method of addition for the same problem are also displayed.

Joiner, David; The Shodor Education Foundation, Inc.

320

Additives boost gasoline quality  

Microsoft Academic Search

Gasoline additives have become more important to the supply of high-quality finished gasoline. Additives are used for the inhibition of oxidation, rust, and gum formation, and for prevention of deposits on and in engine components. The demand for high-quality fuels has led to many different additives that are added at the refinery and downstream. This article describes some of the

Gibbs

1989-01-01

321

Multioperand Decimal Addition  

Microsoft Academic Search

This paper introduces four techniques for performing fast decimal addition on multiple binary coded decimal (BCD) operands. Three of the techniques speculate BCD correction values and use chaining to correct intermediate results. The first speculates over one addition. The second speculates over two additions. The third employs multiple instances of the second technique in parallel and then merges the results.

Robert D. Kenney; Michael J. Schulte

2004-01-01

322

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

323

Effect of particle morphology on resistance to permanent sinking by normal loading of silicon particle in aluminium matrix of a cast aluminium silicon alloy  

Microsoft Academic Search

In pursuing the mechanics of wear of cast aluminium–silicon alloy engine bore we report here the sinking of load bearing silicon protrusions under normal loading. After establishing the buried depth of particles as a function of measurable plan dimensions we experimentally relate the particle morphology to resistance to permanent sinking into the matrix by normal loading. We find this resistance,

Anirban Mahato; Anil K. Sachdev; S. K. Biswas

2008-01-01

324

The properties of reactively sputtered, stoichiometry-controlled and optimum-conductivity transparent zinc\\/aluminium oxide films as a function of their aluminium content  

Microsoft Academic Search

Zinc oxide films doped with controlled amounts of aluminium were made with their stoichiometry controlled to give optimum electrical and optical properties. They were deposited by the successive sputtering of a thin metal film followed by its anodization, using the plasma created by an unbalanced magnetron. Two processes were used: transport between stages and changing the function of an unbalanced

I. Safi; N. Danson; R. P. Howson

1998-01-01

325

Proceedings of International Conference on Aluminium (INCAL `03), Aluminium Association of India, Bangalore, eds S. Subramanian and D. H. Sastry, 2003, pp. 195204. H. K. D. H. Bhadeshia .  

E-print Network

entrapped into the weld. Resistance spot welding of aluminium is difficult (though not impossible) because, including friction­stir welding, flux­free brazing, transient liquid­phase bonding using a temperature; it is impossible in practice to stop it from oxidising at exposed surfaces. It can nevertheless be welded because

Cambridge, University of

326

[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

327

Additives boost gasoline quality  

SciTech Connect

Gasoline additives have become more important to the supply of high-quality finished gasoline. Additives are used for the inhibition of oxidation, rust, and gum formation, and for prevention of deposits on and in engine components. The demand for high-quality fuels has led to many different additives that are added at the refinery and downstream. This article describes some of the most important additives, what they are and what they do, and gives some guidelines on the selection and addition of them to the gasoline product.

Gibbs, L.M.

1989-04-24

328

Involvement of ASR genes in aluminium tolerance mechanisms in rice.  

PubMed

Among cereal crops, rice is considered the most tolerant to aluminium (Al). However, variability among rice genotypes leads to remarkable differences in the degree of Al tolerance for distinct cultivars. A number of studies have demonstrated that rice plants achieve Al tolerance through an unknown mechanism that is independent of root tip Al exclusion. We have analysed expression changes of the rice ASR gene family as a function of Al treatment. The gene ASR5 was differentially regulated in the Al-tolerant rice ssp. Japonica cv. Nipponbare. However, ASR5 expression did not respond to Al exposure in Indica cv. Taim rice roots, which are highly Al sensitive. Transgenic plants carrying RNAi constructs that targeted the ASR genes were obtained, and increased Al susceptibility was observed in T1 plants. Embryogenic calli of transgenic rice carrying an ASR5-green fluorescent protein fusion revealed that ASR5 was localized in both the nucleus and cytoplasm. Using a proteomic approach to compare non-transformed and ASR-RNAi plants, a total of 41 proteins with contrasting expression patterns were identified. We suggest that the ASR5 protein acts as a transcription factor to regulate the expression of different genes that collectively protect rice cells from Al-induced stress responses. PMID:22676236

Arenhart, Rafael Augusto; Lima, Julio César de; Pedron, Marcelo; Carvalho, Fabricio E L; Silveira, Joaquim Albenisio Gomes da; Rosa, Silvia Barcelos; Caverzan, Andreia; Andrade, Claudia M B; Schünemann, Mariana; Margis, Rogério; Margis-Pinheiro, Márcia

2013-01-01

329

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

330

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

331

Hydrogenation of palladium rich compounds of aluminium, gallium and indium  

SciTech Connect

Palladium rich intermetallic compounds of aluminium, gallium and indium have been studied before and after hydrogenation by powder X-ray diffraction and during hydrogenation by in situ thermal analysis (DSC) at hydrogen gas pressures up to 39 MPa and temperatures up to 700 K. Very weak DSC signals and small unit cell increases of below 1% for AlPd{sub 2}, AlPd{sub 3}, GaPd{sub 2}, Ga{sub 5}Pd{sub 13}, In{sub 3}Pd{sub 5}, and InPd{sub 2} suggest negligible hydrogen uptake. In contrast, for both tetragonal modifications of InPd{sub 3} (ZrAl{sub 3} and TiAl{sub 3} type), heating to 523 K at 2 MPa hydrogen pressure leads to a rearrangement of the intermetallic structure to a cubic AuCu{sub 3} type with an increase in unit cell volume per formula unit by 3.6-3.9%. Gravimetric analysis suggests a composition InPd{sub 3}H{sub a}pprox{sub 0.8} for the hydrogenation product. Very similar behaviour is found for the deuteration of InPd{sub 3}. - Graphical abstract: In situ differential scanning calorimetry of the hydrogenation of tetragonal InPd{sub 3} (ZrAl{sub 3} type) at 1.3 MPa hydrogen pressure.

Kohlmann, H., E-mail: h.kohlmann@mx.uni-saarland.d [Saarland University, Inorganic Solid State Chemistry, Saarbruecken (Germany)

2010-02-15

332

Decolourization of melanoidins by a electrocoagulation process using aluminium electrodes.  

PubMed

The decolourization ofmelanoidins was studied with a batch electrocoagulation (EC) process using aluminium electrodes. The effects of conductivity (K = 500-3000 microS/cm), initial pHi (4.2-8.2), current density (j = 2.5-7.5 A/m2), initial melanoidin concentration (C0 = 100-800 mg/L) and operating time (tEC = 0-60 min) were investigated on the decolourization efficiency. The results obtained from the EC process were extremely efficient and able to achieve a decolourization efficiency of > 98% at pHi = 4.2, j = 5 A/m2, K = 2500 microS/cm, C0 = 100 mg/L and tEC = 10 min. The decolourization performance was dependent on pHi value since the lower pH values led to faster reactions and higher decolourization efficiency. Melanoidins in the EC process were removed by precipitation and charge neutralization at pH < 6.5, and both adsorption and sweep coagulation by amorphous Al(OH)3(s) occurred at pH > 6.5. The operating cost was calculated as 0.0096 Euro/m3 PMID:23393986

Kobya, M; Gengec, E

2012-01-01

333

Evidence of superdense aluminium synthesized by ultrafast microexplosion  

SciTech Connect

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 10{sup 4} 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 ({alpha}-Al{sub 2}O{sub 3}). Confined microexplosions offer a strategy to create and recover high-density polymorphs, and a simple method for tabletop study of warm dense matter.

Vailionis, Arturas; Gamaly, Eugene G.; Mizeikis, Vygantas; Yang, Wenge; Rode, Andrei V.; Juodkazis, Saulius (Swinburne); (Stanford); (CIW); (ANU); (Shinshu-MED)

2011-09-20

334

Aluminium intoxication in undialysed adults with chronic renal failure.  

PubMed Central

The dialysis encephalopathy syndrome (DES) consists of altered mental status, communication difficulty, seizures and myoclonus. It has been attributed to elevated serum aluminium (A1) levels. Two undialysed patients with chronic renal failure who presented with the characteristic syndrome are reported. The first, a 48 year old female, had used A1 containing phosphate binders for two years. Her serum A1 level was 25.34 mumol/L. Despite treatment with desferoximine and dialysis, she died. Necropsy revealed elevated A1 levels in the cerebral cortex (19 mcg/gm) and spongioform change in the outer three cortical layers. The second patient, a 46 year old woman, had a serum A1 of 8.70 mumol/L. She had never taken A1 containing phosphate binders but had taken several grams/day of citrate for at least six months. Treatment with haemodialysis and discontinuation of the citrate produced a resolution of symptoms and return of the A1 level to normal. During two years of haemodialysis there has been no recurrence. Images PMID:1527541

Russo, L S; Beale, G; Sandroni, S; Ballinger, W E

1992-01-01

335

Aluminium impact on freshwater invertebrates at low pH: A review  

NASA Astrophysics Data System (ADS)

The state of knowledge on aluminium (Al) impact on freshwater invertebrates at low pH is reviewed. Mainly inorganic ions seem to be biologically harmful. Published effect/mechanism descriptions may seem somewhat contradictory, but this can be due to the heterogeneity of "the invertebrate group", as well as the multitude and complexity of occurring Al species, thereby also Al analysis problems. Addition of Al to streams has in some cases increased drift and death of mainly some "surface-dependent" species (chironomids, mayflies, dance flies, dixid midges), but also some strictly benthic animals (isopods, stoneflies), while other studies on a variety of animals do not record any change in neither drift, mortality nor biomass. In laboratory exposures Al has been shown to cause raised mortality for some daphnids and blackfly larvae at pH around 5; in the latter animals the effect was however mitigated by humus. A variety of other freshwater invertebrates were not affected. Moreover, at pH 4, Al has even been shown to improve the survival of mayfly nymphs and daphnids, otherwise impaired by the low pH in itself. The reason for this is not clear. Proofs for "food chain accumulation" of Al are still weak. Very high additions of Al have caused a decreased respiration rate in a dragonfly nymph, while a more field-relevant exposure level increased respiration in mayfly nymphs. This suggests a stress situation, probably due to impaired osmoregulation, indicating chemical or mechanical Al impact. The lowered oxygen uptake is then compensated for by improved respiration rate. A model for this is presented. Studies on crayfish, daphnids, mayflies and waterbugs indicate that Al can lower osmoregulatory efficiency and thereby affect the ion balance maintaining mechanisms of the animals. Such sublethal effects are important and should be studied further. The review also critically discusses the concepts mortality and bioavailability.

Herrmann, Jan

336

Searching for new aluminium chelating agents: a family of hydroxypyrone ligands.  

PubMed

Attention is devoted to the role of chelating agents in the treatment of aluminium related diseases. In fact, in spite of the efforts that have drastically reduced the occurrence of aluminium dialysis diseases, they so far constitute a cause of great medical concern. The use of chelating agents for iron and aluminium in different clinical applications has found increasing attention in the last thirty years. With the aim of designing new chelators, we synthesized a series of kojic acid derivatives containing two kojic units joined by different linkers. A huge advantage of these molecules is that they are cheap and easy to produce. Previous works on complex formation equilibria of a first group of these ligands with iron and aluminium highlighted extremely good pMe values and gave evidence of the ability to scavenge iron from inside cells. On these bases a second set of bis-kojic ligands, whose linkers between the kojic chelating moieties are differentiated both in terms of type and size, has been designed, synthesized and characterized. The aluminium(III) complex formation equilibria studied by potentiometry, electrospray ionization mass spectroscopy (ESI-MS), quantum-mechanical calculations and (1)H NMR spectroscopy are here described and discussed, and the structural characterization of one of these new ligands is presented. The in vivo studies show that these new bis-kojic derivatives induce faster clearance from main organs as compared with the monomeric analog. PMID:24200878

Toso, Leonardo; Crisponi, Guido; Nurchi, Valeria M; Crespo-Alonso, Miriam; Lachowicz, Joanna I; Mansoori, Delara; Arca, Massimiliano; Santos, M Amélia; Marques, Sérgio M; Gano, Lurdes; Niclós-Gutíerrez, Juan; González-Pérez, Josefa M; Domínguez-Martín, Alicia; Choquesillo-Lazarte, Duane; Szewczuk, Zbigniew

2014-01-01

337

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 ...

Roberts, Ms.

2011-04-20

338

Automating the Addition of  

E-print Network

Automating the Addition of Fault _______________________________________________________________________________* *__ o Why automation o Why transformation - Expected to be simpler than designing from scratch - Necessary if the fault-intolerant program

Kulkarni, Sandeep

339

Models of sweetness additivity  

Microsoft Academic Search

Notes that studies of sweetness additivity reported during the past 50 yrs have suggested 2 potentially different ways by which the taste system adds together different sweet substances in a mixture in order to arrive at a higher level. Type I additivity is characterized by the summation of concentrations in a mixture. The taste system then processes the mixture as

Howard R. Moskowitz

1973-01-01

340

Chloro-sulphur additive  

SciTech Connect

Compounds suitable as extreme pressure additives for lubricating oils are of the general formula CX3-S-S-R where X is a halogen and R is a hydrocarbyl. The performance of the compounds is improved by the addition of a stabilizer.

Lenack, A.L.

1980-10-14

341

Effects of pH and aluminium on the growth and feeding behaviour of smooth and palmate newt larvae  

Microsoft Academic Search

The distribution of smooth and palmate newts (Triturus vulgaris and Triturus helveticus) may be related to water quality. This study compared the larval growth and feeding behaviour of both species under sublethal levels of aluminium and low pH. The growth of both species was inhibited to a similar degree under acidic conditions with aluminium toxicity dependent upon both low pH

L. D. Brady; R. A. Griffiths

1995-01-01

342

Pearlite-like eutectic of ZL 108 aluminium-silicon alloy containing rare-earth elements rapidly solidified by laser  

Microsoft Academic Search

Cast aluminium alloys with eutectic composition have been frequently used in industry owing to their low cost, simple processing and light weight. Their mechanical properties strongly depend on their eutectic microstructure. Such methods as adding elements and rapid solidification have been widely used to refine the eutectic. A lot of work on the eutectic structure in cast aluminium alloys has

H. Jiandong; L. Yongbing; L. Zhang

1990-01-01

343

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

344

Further studies of the anodic dissolution in sodium chloride electrolyte of aluminium alloys containing tin and gallium  

Microsoft Academic Search

As part of a programme to develop a high power density, Al\\/air battery with a NaCl brine electrolyte, the high rate dissolution of an aluminium alloy containing tin and gallium was investigated in a small volume cell. The objective was to define the factors that limit aluminium dissolution in condition that mimic a high power density battery. In a cell

Maria Nestoridi; Derek Pletcher; Julian A. Wharton; Robert J. K. Wood

2009-01-01

345

Formation of nano-sized alumina by in-flight oxidation of aluminium powder in a thermal plasma reactor  

Microsoft Academic Search

Nano-sized aluminium oxide powder has been synthesized in a thermal plasma reactor by in-flight oxidation of aluminium metal. The particle size of alumina formed ranges from a few nanometers to 30 nm. Experimental studies have been complemented by numerical process simulation using a one-dimensional model.

P. V. Ananthapadmanabhan; T. K. Thiyagarajan; K. P. Sreekumar; N. Venkatramani

2004-01-01

346

New iron–aluminium alloy with thermally stable coherent intermetallic nanoprecipitates for enhanced high-temperature creep strength  

Microsoft Academic Search

Poor ductility and strength at high temperatures, especially under slow strain rate or creep conditions, have prevented the use of iron–aluminium alloys or aluminide intermetallics, despite decades of intensive research. The low strength at high temperature is due to the inability of hardening particles such as carbides to resist dissolution or coarsening at these temperatures. A new iron–aluminium alloy with

D. G. Morris; M. A. Muñoz-Morris; L. M. Requejo

2006-01-01

347

Eco-friendly corrosion inhibitors: the inhibitive action of Delonix Regia extract for the corrosion of aluminium in acidic media  

Microsoft Academic Search

Purpose – To investigate the inhibitive effect of Delonix regia extracts to reduce the corrosion rate of aluminium in acidic media. The study was a trial to find a low cost and environmentally safe inhibitor to reduce the corrosion rate of aluminium. Design\\/methodology\\/approach – The inhibition efficiency was evaluated using the hydrogen evolution technique at 30°C. The mechanism of adsorption

O. K. Abiola; N. C. Oforka; E. E. Ebenso; N. M. Nwinuka

2007-01-01

348

The Relationship of the Aluminium Phosphate Precipitation of Organisms of Haemophilus pertussis strains to their other Biological Properties  

Microsoft Academic Search

SUMMARY: Of 46 strains of Haemophilus pertussis, 34 recently isolated strains were all agglutinated by Phase 1 antiserum. Of 12 laboratory strains, 5 had lost their agglutinability. The agglutinable strains were precipitated by aluminium phosphate, and lysed by sodium hydroxide or 10% sodium desoxycholate and were virulent to mice. The virulent strains, which were precipitable by aluminium phosphate, produced toxic

J. Ungar; P. W. Muggleton

1949-01-01

349

Effects of anodized aluminium surface parameters on the long-term adhesion of silicone structural glazing sealants  

Microsoft Academic Search

The quality of silicone sealant adhesion to anodized aluminium varies widely. Key parameters that affect adhesion are the degree of surface sealing, the pigmentation of the anodization layer, the nature of the cleaner, and the time period allowed between cleaning the substrate and sealant application. While the cleaners display different effectiveness in removing organic contamination from the anodized aluminium surface,

Pierre Descamps; Jean Iker; Andreas T. Wolf

1996-01-01

350

Jaguar uses adaptive MIG welding to join C-pillars to an aluminium roof section in a new sports car  

Microsoft Academic Search

Purpose – To describe how Jaguar Cars in the UK is making use of a robot-based intelligent adaptive metal inert gas (MIG) welding process incorporating laser diode measurement of the gap in the joint between the aluminium C-pillars and the aluminium roof structure of its new XK sports car that is being built in the company's plant in Castle Bromwich,

John Mortimer

2006-01-01

351

Etude de la complexation des ions aluminium par des molécules organiques: Constantes et stoechiométrie des complexes. Application au traitement de potabilisation des eaux  

Microsoft Academic Search

Aluminium salts are commonly used as reactants for coagulation-flocculation in the treatment of drinking water supplies. Powdered activated carbon (PAC) is also sometimes used to decrease accidental or chronic organic pollution. If organic matter has to be removed, powdered activated carbon and aluminium salts can be used simultaneously. The aluminium salts and natural organic matter such as fulvic acids will

G Cathalifaud; J Ayele; M Mazet

1997-01-01

352

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

353

In situ nanoindentation study on plasticity and work hardening in aluminium with incoherent twin boundaries.  

PubMed

Nanotwinned metals have been the focus of intense research recently, as twin boundaries may greatly enhance mechanical strength, while maintaining good ductility, electrical conductivity and thermal stability. Most prior studies have focused on low stacking-fault energy nanotwinned metals with coherent twin boundaries. In contrast, the plasticity of twinned high stacking-fault energy metals, such as aluminium with incoherent twin boundaries, has not been investigated. Here we report high work hardening capacity and plasticity in highly twinned aluminium containing abundant ?3{112} incoherent twin boundaries based on in situ nanoindentation studies in a transmission electron microscope and corresponding molecular dynamics simulations. The simulations also reveal drastic differences in deformation mechanisms between nanotwinned copper and twinned aluminium ascribed to stacking-fault energy controlled dislocation-incoherent twin boundary interactions. This study provides new insight into incoherent twin boundary-dominated plasticity in high stacking-fault energy twinned metals. PMID:25204688

Bufford, D; Liu, Y; Wang, J; Wang, H; Zhang, X

2014-01-01

354

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

355

In situ nanoindentation study on plasticity and work hardening in aluminium with incoherent twin boundaries  

NASA Astrophysics Data System (ADS)

Nanotwinned metals have been the focus of intense research recently, as twin boundaries may greatly enhance mechanical strength, while maintaining good ductility, electrical conductivity and thermal stability. Most prior studies have focused on low stacking-fault energy nanotwinned metals with coherent twin boundaries. In contrast, the plasticity of twinned high stacking-fault energy metals, such as aluminium with incoherent twin boundaries, has not been investigated. Here we report high work hardening capacity and plasticity in highly twinned aluminium containing abundant ?3{112} incoherent twin boundaries based on in situ nanoindentation studies in a transmission electron microscope and corresponding molecular dynamics simulations. The simulations also reveal drastic differences in deformation mechanisms between nanotwinned copper and twinned aluminium ascribed to stacking-fault energy controlled dislocation-incoherent twin boundary interactions. This study provides new insight into incoherent twin boundary-dominated plasticity in high stacking-fault energy twinned metals.

Bufford, D.; Liu, Y.; Wang, J.; Wang, H.; Zhang, X.

2014-09-01

356

A role for the body burden of aluminium in vaccine-associated macrophagic myofasciitis and chronic fatigue syndrome.  

PubMed

Macrophagic myofasciitis and chronic fatigue syndrome are severely disabling conditions which may be caused by adverse reactions to aluminium-containing adjuvants in vaccines. While a little is known of disease aetiology both conditions are characterised by an aberrant immune response, have a number of prominent symptoms in common and are coincident in many individuals. Herein, we have described a case of vaccine-associated chronic fatigue syndrome and macrophagic myofasciitis in an individual demonstrating aluminium overload. This is the first report linking the latter with either of these two conditions and the possibility is considered that the coincident aluminium overload contributed significantly to the severity of these conditions in this individual. This case has highlighted potential dangers associated with aluminium-containing adjuvants and we have elucidated a possible mechanism whereby vaccination involving aluminium-containing adjuvants could trigger the cascade of immunological events which are associated with autoimmune conditions including chronic fatigue syndrome and macrophagic myofasciitis. PMID:19004564

Exley, Christopher; Swarbrick, Louise; Gherardi, Rhomain K; Authier, Francois-Jérôme

2009-02-01

357

Sol-gel synthesis and characterization of sub-microsized lanthanide (Ho, Tm, Yb, Lu) aluminium garnets  

NASA Astrophysics Data System (ADS)

Sub-microsized and nanosized holmium aluminium garnet (Ho 3Al 5O 12, HoAG), thulium aluminium garnet (Tm 3Al 5O 12, TmAG), ytterbium aluminium garnet (Yb 3Al 5O 12, YbAG) and lutetium aluminium garnet (Lu 3Al 5O 12, LuAG) powders were prepared by a simple aqueous sol-gel method using aluminium nitrate nonahydrate, lutetium oxide, thulium oxide, holmium oxide and ytterbium oxide as starting materials. Ethane-1,2-diol was used as complexing agent. The powder X-ray diffraction (XRD) patterns of the specimens sintered at 1000 °C revealed the formation of monophasic HoAG, TmAG, YbAG, and LuAG. The phase composition of the samples was also characterized by infrared (IR) spectroscopy. Microstructural features of the polycrystalline garnets were studied by scanning electron microscopy (SEM).

Dubnikova, N.; Garskaite, E.; Beganskiene, A.; Kareiva, A.

2011-06-01

358

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

359

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

360

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 the 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.

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

1993-01-01

361

Zinc modulates aluminium-induced oxidative stress and cellular injury in rat brain.  

PubMed

Dysregulation of metal homeostasis has been perceived as one of the key factors in the progression of neurodegeneration. Aluminium (Al) has been considered as a major risk factor, which is linked to several neurodegenerative diseases, especially Alzheimer's disease, whereas zinc (Zn) has been reported as a vital dietary element, which regulates a number of physiological processes in central nervous system. The present study was conducted to explore the protective potential of zinc, if any, in ameliorating neurotoxicity induced by aluminium. Male Sprague Dawley rats received either aluminium chloride (AlCl3) orally (100 mg kg(-1) b.wt. per day), zinc sulphate (ZnSO4) at a dose level of 227 mg L(-1) in drinking water or combined treatment of aluminium and zinc for 8 weeks. Aluminium treatment significantly elevated the levels of lipid peroxidation and reactive oxygen species as well as the activities of catalase, superoxide dismutase and glutathione reductase, which however were decreased following Zn co-treatment of Al-treated rats. In contrast, Al treatment decreased the activities of glutathione-S-transferase as well as the levels of reduced glutathione, oxidised glutathione and total glutathione, but co-administration of Zn to Al-treated animals increased these levels. Furthermore, Al treatment caused a significant increase in the levels of Fe and Mn as well as of Al but decreased the Zn and metallothionein levels. In the Zn-supplemented animals, the levels of Al, Fe, Mn were found to be significantly decreased, whereas the levels of metallothionein as well as Zn were increased. Moreover, histopathological alterations such as vacuolization and loss of Purkinje cells were also evident following Al treatment, which showed improvement upon Zn supplementation. Therefore, zinc has the potential to alleviate aluminium-induced neurodegeneration. PMID:25141099

Singla, Neha; Dhawan, D K

2014-10-01

362

Aluminium speciation in 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide/AlCl3 mixtures.  

PubMed

Electrodeposition of aluminium is possible from solutions of AlCl(3) dissolved in the 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide (C(4)mpyrNTf(2)) ionic liquid. However, electrodeposition is dependant on the AlCl(3) concentration as it only occurs at concentrations >1.6 mol L(-1). At these relatively high AlCl(3) concentrations the C(4)mpyrNTf(2)/AlCl(3) mixtures exhibit biphasic behaviour. Notably, at 1.6 mol L(-1) AlCl(3), aluminium can only be electrodeposited from the upper phase. Conversely, we found that at 3.3 mol L(-1) aluminium electrodeposition can only occur from the lower phase. The complex chemistry of the C(4)mpyrNTf(2)/AlCl(3) system is described and implications of aluminium speciation in several C(4)mpyrNTf(2)/AlCl(3) mixtures, as deduced from Raman and (27)Al NMR spectroscopic data, are discussed. The (27)Al NMR spectra of the C(4)mpyrNTf(2)/AlCl(3) mixtures revealed the presence of both tetrahedrally and octahedrally coordinated aluminium species. Raman spectroscopy revealed that the level of uncoordinated NTf(2)(-) anions decreased with increasing AlCl(3) concentration. Quantum chemical calculations using density functional and ab initio theory were employed to identify plausible aluminium-containing species and to calculate their vibrational frequencies, which in turn assisted the assignment of the observed Raman bands. The data indicate that the electroactive species involved are likely to be either [AlCl(3)(NTf(2))](-) or [AlCl(2)(NTf(2))(2)](-). PMID:19132700

Rocher, Nathalie M; Izgorodina, Ekaterina I; Rüther, Thomas; Forsyth, Maria; Macfarlane, Douglas R; Rodopoulos, Theo; Horne, Michael D; Bond, Alan M

2009-01-01

363

Protective role of Cynodon dactylon in ameliorating the aluminium-induced neurotoxicity in rat brain regions.  

PubMed

Cynodon dactylon (Poaceae) is a creeping grass used as a traditional ayurvedic medicine in India. Aluminium-induced neurotoxicity is well known and different salts of aluminium have been reported to accelerate damage to biomolecules like lipids, proteins and nucleic acids. The objective of the present study was to investigate whether the aqueous extract of C. dactylon (AECD) could potentially prevent aluminium-induced neurotoxicity in the cerebral cortex, hippocampus and cerebellum of the rat brain. Male albino rats were administered with AlCl(3) at a dose of 4.2 mg/kg/day i.p. for 4 weeks. Experimental rats were given C. dactylon extract in two different doses of 300 mg and 750 mg/keg/day orally 1 h prior to the AlCl(3) administration for 4 weeks. At the end of the experiments, antioxidant status and activities of ATPases in cerebral cortex, hippocampus and cerebellum of rat brain were measured. Aluminium administration significantly decreased the level of GSH and the activities of SOD, GPx, GST, Na(+)/K(+) ATPase, and Mg(2+) ATPase and increased the level of lipid peroxidation (LPO) in all the brain regions when compared with control rats. Pre-treatment with AECD at a dose of 750 mg/kg b.w increased the antioxidant status and activities of membrane-bound enzymes (Na(+)/K(+) ATPase and Mg(2+) ATPase) and also decreased the level of LPO significantly, when compared with aluminium-induced rats. The results of this study indicated that AECD has potential to protect the various brain regions from aluminium-induced neurotoxicity. PMID:21448563

Sumathi, Thangarajan; Shobana, Chandrasekar; Kumari, Balasubramanian Rathina; Nandhini, Devarajulu Nisha

2011-12-01

364

Aluminium induced oxidative stress results in decreased mitochondrial biogenesis via modulation of PGC-1? expression.  

PubMed

The present investigation was carried out to elucidate a possible molecular mechanism related to the effects of aluminium-induced oxidative stress on various mitochondrial respiratory complex subunits with special emphasis on the role of Peroxisome proliferator activated receptor gamma co-activator 1? (PGC-1?) and its downstream targets i.e. Nuclear respiratory factor-1(NRF-1), Nuclear respiratory factor-2(NRF-2) and Mitochondrial transcription factor A (Tfam) in mitochondrial biogenesis. Aluminium lactate (10mg/kgb.wt./day) was administered intragastrically to rats for 12 weeks. After 12 weeks of exposure, we found an increase in ROS levels, mitochondrial DNA oxidation and decrease in citrate synthase activity in the Hippocampus (HC) and Corpus striatum (CS) regions of rat brain. On the other hand, there was a decrease in the mRNA levels of the mitochondrial encoded subunits-NADH dehydrogenase (ND) subunits i.e. ND1, ND2, ND3, Cytochrome b (Cytb), Cytochrome oxidase (COX) subunits i.e. COX1, COX3, ATP synthase (ATPase) subunit 6 along with reduced expression of nuclear encoded subunits COX4, COX5A, COX5B of Electron transport chain (ETC). Besides, a decrease in mitochondrial DNA copy number and mitochondrial content in both regions of rat brain was observed. The PGC-1? was down-regulated in aluminium treated rats along with NRF-1, NRF-2 and Tfam, which act downstream from PGC-1? in aluminium treated rats. Electron microscopy results revealed a significant increase in the mitochondrial swelling, loss of cristae, chromatin condensation and decreases in mitochondrial number in case of aluminium treated rats as compared to control. So, PGC-1? seems to be a potent target for aluminium neurotoxicity, which makes it an almost ideal target to control or limit the damage that has been associated with the defective mitochondrial function seen in neurodegenerative diseases. PMID:24084166

Sharma, Deep Raj; Sunkaria, Aditya; Wani, Willayat Yousuf; Sharma, Reeta Kumari; Kandimalla, Ramesh J L; Bal, Amanjit; Gill, Kiran Dip

2013-12-01

365

AdditionalBooks  

Cancer.gov

While we tried to include potentially useful resources, this website is not exhaustive. New and additional resources may be available. Please let us know if there is a resource you would like to be included.

366

Food Additives and Hyperkinesis  

ERIC Educational Resources Information Center

The hypothesis that food additives are causally associated with hyperkinesis and learning disabilities in children is reviewed, and available data are summarized. Available from: American Medical Association 535 North Dearborn Street Chicago, Illinois 60610. (JG)

Wender, Ester H.

1977-01-01

367

Deck addition at Palmer <  

NSF Publications Database

... EAM NSF Org: OD / OPP Date : January 31, 1991 File : opp93020 DIVISION OF POLAR PROGRAMS OFFICE OF ... Deck Addition at Palmer Station BioLab) To: Files (S.7 - Environment) On January 18, 1991, the ...

368

Palmer boathouse addition <  

NSF Publications Database

... EAM NSF Org: OD / OPP Date : January 31, 1991 File : opp93021 OFFICE OF SAFETY, ENVIRONMENT AND ... Palmer Station Boathouse Addition) To: Files (S.7 - Environment) On January 16, 1991, the civilian ...

369

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

370

Development of anodes for aluminium\\/air batteries — solution phase inhibition of corrosion  

Microsoft Academic Search

The discharge characteristics of aluminium in inhibited and uninhibited 4 M KOH at 50°C have been explored. The performance of pure aluminium as a fuel is compared with that for two leading alloy fuels that had been evaluated in our previous work, Alloy BDW (Al-1Mg-0.1In-0.2Mn) and Alloy 21 (Al-0.2Ga-0.1In-0.1Tl). The inhibitors employed in this study, SnO32-, In(OH)3, BiO33-, Ga(OH)4-, MnO42-,

D. D. Macdonald; C. English

1990-01-01

371

Electrochemical synthesis of macroporous aluminium films and their behavior towards lithium deposition/stripping  

NASA Astrophysics Data System (ADS)

In the present study macroporous aluminium electrodes were made by template assisted electrodeposition from ionic liquids. Polystyrene (PS) spheres (diameter 600 nm) were applied onto polished copper electrodes by immersion into an alcoholic suspension containing PS spheres. Al was deposited from the chloroaluminate ionic liquid [EMIm]Cl/AlCl3 (40/60 mol.%) on this substrate. After chemical dissolution of the PS spheres a macroporous aluminium electrode was obtained which served as a host material for Li deposition from ionic liquids. Lithium deposition in this matrix is reversible showing certain activation with an increasing number of cycles. After 10 cycles of Li deposition/dissolution the macroporous structure is still visible.

Gasparotto, L. H. S.; Prowald, A.; Borisenko, N.; El Abedin, S. Zein; Garsuch, A.; Endres, F.

2011-03-01

372

A ToF-SIMS study of linseed oil bonded to mercapto silane treated aluminium  

NASA Astrophysics Data System (ADS)

ToF-SIMS has been used to analyse an aluminium surface treated with a vegetable oil using a mercapto silane as a coupling agent between the aluminium substrate and the vegetable oil. The coupling between the vegetable oil and the mercapto silane was obtained through a photoinduced thiol-ene reaction using UV-radiation. The ToF-SIMS results show that the desired thiol-ene reaction has taken place between the unsaturated parts of the vegetable oil and the thiol groups of the mercapto silane via the thiol-ene reaction forming a surface film.

Bexell, U.; Olsson, M.; Sundell, P.-E.; Johansson, M.; Carlsson, P.; Hellsing, M.

2004-06-01

373

Fibre-optic titrations-IV Direct complexometric titration of aluminium(III) with DCTA.  

PubMed

The end-point of the direct complexometric titration of Al(3+) in pH 4.6 solution can be determined by monitoring the fluorescence intensity of the aluminium-morin complex, by use of a bifurcated fibre-optic light guide. The method allows the determination of aluminium in the 1-800 ppm range with good precision. The procedure is applicable even when the solutions are strongly coloured or turbid, but because of the slow complexation kinetics requires a titration time of about 20 min. PMID:18964217

Wolfbeis, O S; Schaffar, B P; Chalmers, R A

1986-11-01

374

PIXE analysis for the study of toxic effects of aluminium in vines  

NASA Astrophysics Data System (ADS)

Elemental concentrations of Mg, A1, Si, P, S, Cl, K and Ca were determined by PIXE in various parts of grape vines grown in a Hoagland water culture with and without added aluminium. The presence of Al enhanced the uptake of P, S and K in leaves and stems, but depressed Mg and Ca. In the roots the Al concentration was very high, while that of Mg was reduced compared to the control samples. The toxic effects of aluminium produced symptoms reminiscent of calcium deficiency.

Meyer, B. R.; Le Roux, E.; Renan, M. J.; Peisach, M.

1984-04-01

375

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.

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

2013-01-01

376

Numerical analysis of experiments on the generation of shock waves in aluminium under indirect (X-ray) action on the Iskra-5 facility  

NASA Astrophysics Data System (ADS)

The dynamics of laser and X-ray radiation fields in experiments with cylindrical converter boxes (illuminators), which had earlier been carried out on the Iskra-5 laser facility (the second harmonic of iodine laser radiation, ? = 0.66 ?m) was investigated in a sector approximation using the SND-LIRA numerical technique. In these experiments, the X-ray radiation temperature in the box was determined by measuring the velocity of the shock wave generated in the sample under investigation, which was located at the end of the cylindrical illuminator. Through simulations were made using the SND-LIRA code, which took into account the absorption of laser driver radiation at the box walls, the production of quasithermal radiation, as well as the formation and propagation of the shock wave in the sample under investigation. An analysis of the experiments permits determining the electron thermal flux limiter f: for f = 0.03 it is possible to match the experimental scaling data for X-ray in-box radiation temperature to the data of our simulations. The shock velocities obtained from the simulations are also consistent with experimental data. In particular, in the experiment with six laser beams (and a laser energy EL = 1380 J introduced into the box) the velocity of the shock front (determined from the position of a laser mark) after passage through a 50-?m thick base aluminium layer was equal to 35+/-1.6 km s-1, and in simulations to 36 km s-1. In the experiment with four laser beams (for EL = 850 J) the shock velocity (measured from the difference of transit times through the base aluminium layer and an additional thin aluminium platelet) was equal to 30+/-3.6 km s-1, and in simulations to 30 km s-1.

Bondarenko, S. V.; Dolgoleva, G. V.; Novikova, E. A.

2013-07-01

377

Numerical analysis of experiments on the generation of shock waves in aluminium under indirect (X-ray) action on the Iskra-5 facility  

SciTech Connect

The dynamics of laser and X-ray radiation fields in experiments with cylindrical converter boxes (illuminators), which had earlier been carried out on the Iskra-5 laser facility (the second harmonic of iodine laser radiation, {lambda} = 0.66 {mu}m) was investigated in a sector approximation using the SND-LIRA numerical technique. In these experiments, the X-ray radiation temperature in the box was determined by measuring the velocity of the shock wave generated in the sample under investigation, which was located at the end of the cylindrical illuminator. Through simulations were made using the SND-LIRA code, which took into account the absorption of laser driver radiation at the box walls, the production of quasithermal radiation, as well as the formation and propagation of the shock wave in the sample under investigation. An analysis of the experiments permits determining the electron thermal flux limiter f: for f = 0.03 it is possible to match the experimental scaling data for X-ray in-box radiation temperature to the data of our simulations. The shock velocities obtained from the simulations are also consistent with experimental data. In particular, in the experiment with six laser beams (and a laser energy E{sub L} = 1380 J introduced into the box) the velocity of the shock front (determined from the position of a laser mark) after passage through a 50-{mu}m thick base aluminium layer was equal to 35{+-}1.6 km s{sup -1}, and in simulations to 36 km s{sup -1}. In the experiment with four laser beams (for E{sub L} = 850 J) the shock velocity (measured from the difference of transit times through the base aluminium layer and an additional thin aluminium platelet) was equal to 30{+-}3.6 km s{sup -1}, and in simulations to 30 km s{sup -1}. (interaction of laser radiation with matter)

Bondarenko, S V; Dolgoleva, G V; Novikova, E A

2013-07-31

378

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

379

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

380

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

381

Diesel fuel additive  

SciTech Connect

This patent describes a diesel fuel additive composition. It comprises about 6.0 weight percent di-tertiary butyl peroxide, about 1.0 weight percent tall oil fatty imidazoline, about 0.5 weight percent neo decanoic acid, the balance being a hydrocarbon solvent carrier.

Vataru, M.; Filowitz, M.S.

1989-08-15

382

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

383

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

384

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

385

Columnar to equiaxed transition of eutectic in hypoeutectic aluminium–silicon alloys  

Microsoft Academic Search

Directional solidification of unmodified and strontium modified binary, high-purity, aluminium–7 wt% silicon and commercial A356 alloys has been carried out to investigate the mechanism of eutectic solidification. The microstructure of the eutectic growth interface was investigated with optical microscopy and Electron Backscattering Diffraction (EBSD). In the commercial alloys, the eutectic solidification interface extends in the growth direction and creates a

G. Heiberg; K. Nogita; A. K. Dahle; L. Arnberg

2002-01-01

386

Boundary Lubricated Tribology of an Aluminium-Silicon Alloy Sliding Against Steel  

Microsoft Academic Search

We have slid steel pins on aluminium-silicon alloy discs in the boundary lubrication regime in the presence of one drop of oil. We have explored the effect of base oil and additivated engine oil on friction and wear and analyzed the data in terms of the formation of a mechanically mixed layer at the interface and the corrosive action of

Sarmistha Das; S. K. Biswas

2004-01-01

387

Influence of titanium to boron ratio on the ability to grain refine aluminium-silicon alloys  

Microsoft Academic Search

Grain refinement is achieved in aluminium alloys by inoculating the molten metal with small amounts of titanium and boron. Grain refiners containing high concentrations of titanium and boron are available commercially for this purpose. However, these grain refiners come in different chemical compositions giving rise to a variety of Ti\\/B ratios. Although it is accepted that increasing the amount of

T. Sritharan; H. Li

1997-01-01

388

Effects of strontium on the structure and properties of aluminium-silicon alloys  

Microsoft Academic Search

In this study, modification of aluminium-silicon eutectic alloy by strontium was investigated and shown to improve the tensile properties of the alloy. The evaluation of the modification was done metallographically. The tensile properties were obtained from round, cast to shape and size, test bars which were produced in green sand moulds and cast iron chill moulds. The appearance of the

M. M. Haque

1995-01-01

389

Role of silicon in resisting subsurface plastic deformation in tribology of aluminium–silicon alloys  

Microsoft Academic Search

Silicon particles standing proud on aluminium–silicon alloy surfaces provide protection in tribology. Permanent sinking of such particles into the matrix under load can be deleterious. The mechanical response of the alloy to nano-indentation of single silicon particles embedded in the matrix is explored. A nominal critical pressure required to plastically deform the matrix to permanently embed the particle is determined

Anirban Mahato; Shuman Xia; Tom Perry; Anil Sachdev; S. K. Biswas

2010-01-01

390

Simulation of the three-dimensional morphology of solidification porosity in an aluminium–silicon alloy  

Microsoft Academic Search

A novel extension of the cellular automata technique for microstructural modelling is presented, allowing simulation of the evolution of the complex three-dimensional morphology of porosity during the solidification of an aluminium–silicon alloy. The complex morphology arises due to the restriction of the growth of the pores by the developing solid phase. The model predicts the average properties of the porosity

R. C. Atwood; P. D. Lee

2003-01-01

391

Influence of Flow Arrangement on the Performance of an Aluminium Microchannel Heat Exchanger  

Microsoft Academic Search

The present study investigated the influence of flow arrangement on the performance index (expressed as the ratio of the heat transfer rate to the pressure drop) of an aluminium microchannel heat exchanger. The results were obtained by both numerical simulations and experimental data. For all cases done in this study, the performance index obtained from the counter-flow arrangement is always

Thanhtrung Dang; Jyh-Tong Teng

2010-01-01

392

Dental Caries and the Concentration of Aluminium and Strontium in Enamel  

Microsoft Academic Search

The concentration of aluminium and strontium was determined (by AAS) in soil (total and exchangeable), drinking water and dental enamel from an area (Zemunik) with low caries prevalence (DMFT < 2). For comparison purposes, similar samples were collected and analyzed from another village (Novigrad) in the same region with normal caries prevalence (DMFT > 5). A positive correlation between low

J. Štupar

1980-01-01

393

Investigations of the human aluminium biokinetics with 26Al and AMS  

Microsoft Academic Search

Continuing the investigations on two healthy volunteers and on two patients with renal failure, the aluminium biokinetics in humans was studied by administering oral and intravenous doses of 26Al to three further healthy volunteers. Blood samples were drawn at times between 20 min and half a year after administration of the doses. The complete daily urine was collected during the

G. Kislinger; C. Steinhausen; M. Alvarez-Brückmann; C. Winklhofer; T.-H. Ittel; E. Nolte

1997-01-01

394

A FINITE ELEMENT APPROACH FOR SIMULATING THE QUENCHING OF LARGE ALUMINIUM COMPRESSOR WHEELS  

E-print Network

as shown in Figure 1. A wheel is made out of one massive billet and is quenched in hot water. A 3D-FE model whereas the areas near the main mass of the wheel are still hot and surrounded by bubbles (Figure 2 rightA FINITE ELEMENT APPROACH FOR SIMULATING THE QUENCHING OF LARGE ALUMINIUM COMPRESSOR WHEELS

395

Comparison of aluminium and stainless steel built-in-storage solar water heater  

Microsoft Academic Search

This article provides the results and findings of an experimental work undertaken in Pakistan that aimed to compare the performance of stainless steel and aluminium make built-in-storage solar waters. The experimental work undertaken as part of this project included design and development of the 2 solar water heaters as well as their operation and data collation over a period of

M. Asif; J. Currie; T. Muneer

2007-01-01

396

Effect of aluminium doping on zinc oxide thin films grown by spray pyrolysis  

Microsoft Academic Search

We report the structural, optical, and electrical characterization of aluminium-doped zinc oxide thin films grown by the spray pyrolysis method. We report the effect of Al concentration on the resistivity and on the X-ray diffraction, transmittance, photoluminescence and Raman scattering spectra of the films. The minimum resistivity is obtained for the sample with nominal Al concentration of 1%. An increase

A. El Manouni; F. J. Manjón; M. Mollar; B. Marí; R. Gómez; M. C. López; J. R. Ramos-Barrado

2006-01-01

397

X-ray Emission Spectroscopic Investigation of Sealing of Anodic Oxide Films on Aluminium  

Microsoft Academic Search

`SEALING' of oxide coatings produced on aluminium and its alloys by anodic treatment in sulphuric acid solutions is the reaction between the amorphous alumina (containing about 15 per cent sulphate) and boiling water or aqueous metal salt solutions. X-ray emission spectroscopy provides a new and useful technique to study the sealing reaction through its quantitative and quick determination of the

Roy C. Spooner; W. J. Forsyth

1963-01-01

398

Estimating streamwater concentrations of aluminium released from streambeds during ‘acid episodes’  

Microsoft Academic Search

Rates of release of monomeric aluminium ? Alm ? were determined for streambed materials placed in a laboratory channel and exposed to acid water, and values of the release rate coefficient, R (?mol Al released per m of bed per second) were calculated. Estimates of R were also made from the reported results of experiments in which streams were artificially

E. Tipping; J. Hopwood

1988-01-01

399

Anodische Oxidation von Reinstaluminium in sauren Elektrolyten. (Anodic oxidation of high purity aluminium in acid electrolytes).  

National Technical Information Service (NTIS)

In this dissertation, the anodic oxidation and dissolution of pure aluminium in 3 molar H2SO4 was studied. The goal of this investigation was the optimisation of the acidic Al/Air-battery. To investigate the surface of the electrode, methods such as ellip...

B. Schnyder

1994-01-01

400

Dynamic fracture toughness of aluminium 6063 with multilayer composite patching at lower temperatures  

Microsoft Academic Search

Aluminium alloys provide many benefits and challenges for use in marine environment. Attention on lightweight hulls leads to power saving, better handling and easy transportation. The stiffness and mass of the structure or member is responsible for its natural vibration. The hull panels and stiffeners vibrate at different frequencies when their stiffness is reduced by formation of a crack or

G. L. Manjunath; S. Surendran

2012-01-01

401

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

E-print Network

concentration at the metal surface since the exper- imental values of the corrosion potential Ecorr became more corrosion protection by reducing the oxygen concentration at the metal surface [8±10]. Protective bioPitting corrosion control using regenerative bio®lms on aluminium 2024 in arti®cial seawater D

Wood, Thomas K.

402

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

403

Corrosion behaviour of friction stir welded AA7108 T79 aluminium alloy  

Microsoft Academic Search

The corrosion behaviour of a friction stir welded AA7108 T79 aluminium alloy has been investigated using accelerated testing (ASTM G34 EXCO) and electrochemical measurements. The welded alloy showed the expected zones associated with friction stir welding, namely nugget, thermomechanically affected zone and heat affected zone. Corrosion testing revealed that the edge regions of the thermomechanically affected zone were most susceptible

D. A. Wadeson; X. Zhou; G. E. Thompson; P. Skeldon; L. Djapic Oosterkamp; G. Scamans

2006-01-01

404

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

405

Fatigue analysis of friction stir welded aluminium profile using critical distance  

Microsoft Academic Search

A friction stir (FS) welded extruded aluminium alloy 6005A, which is used for train wall sides, was fatigue tested. The friction stir weld was a lap-butt joint with a sharp notch (interface between the work pieces) next to the weld nugget. Fatigue cracks and failure appeared at notches in the profile. In most profiles, cracks also initiated at the sharp

Meysam Mahdavi Shahri; Rolf Sandström

2010-01-01

406

Electromagnetic radiation during opening and shearing modes of fracture in commercially pure aluminium at elevated temperature  

Microsoft Academic Search

This paper reports some significant characteristics of electromagnetic radiation (EMR) emitted from commercially pure aluminium strips under opening and shearing modes of fracture at elevated temperatures. It is observed that elevated temperatures affect only the kHz component frequency of EMR, the MHz component in opening mode remains uninfluenced. Shearing mode of fracture did not emit any MHz component frequency EMR

B. Srilakshmi; Ashok Misra

2005-01-01

407

Aluminium impact on freshwater invertebrates at low pH: A review  

Microsoft Academic Search

The state of knowledge on aluminium (Al) impact on freshwater invertebrates at low pH is reviewed. Mainly inorganic ions seem to be biologically harmful. Published effect\\/mechanism descriptions may seem somewhat contradictory, but this can be due to the heterogeneity of \\

Jan Herrmann

1987-01-01

408

Mechanism of Alzheimer's disease: Arguments for a neurotransmitter-aluminium complex implication  

Microsoft Academic Search

The authors are convinced that in Alzheimer's disease, as in Down's syndrome and Guam-Parkinson dementia, one may find an alteration in blood brain barrier transfer and a resultant imbalance in mineral metabolism. Metals, such as aluminium, which in vivo yield stable complexes with aspartic and glutamic acids act as previously been clearly shown with glutamic acid; they cross the blood

Roger Delonele I; Olivier Guillard

1990-01-01

409

Thermoelectric power of undoped and aluminium oxide doped ferroelectric potassium vanadate and cesium vanadate  

Microsoft Academic Search

The thermoelectric power(s) of pure and aluminium oxide doped ferroelectric potassium vanadate and cesium vanadate have been determined in the temperature range covering their transition temperature. The thermoelectric power is found to increase linearly with temperature, attains maximum value and with further increase in temperature decreases to zero indicating transition temperature of the respective samples while it changes sign for

S. P. Rasal; T. S. Magdum; D. V. Pawar; S. H. Chavan

1993-01-01

410

Studies on dielectric and hysteresis properties of undoped and aluminium oxide doped ferroelectric cesium vanadate  

Microsoft Academic Search

The effect of aluminium doping, as an acceptor impurity on the polycrystalline cesium vanadate has been studied in the temperature range covering their transition points. The dielectric constant is measured by 'comparison of capacities' while the coercive field is evaluated using hysteresis loop. It is seen that the dielectric constant as well as the coercive field are remarkably depending on

S. P. Rasal; V. V. Patil; A. J. Kulkarni; S. H. Chavan

1991-01-01

411

Inhibition effects of some plant extracts on the acid corrosion of aluminium alloy  

Microsoft Academic Search

Corrosion inhibition of aluminium alloy (AA3003) in 0.5 M HCl by extracts of selected plants was investigated using gravimetric technique at 30 and 60°C. The studied plant materials include extracts of Euphorbia hirta and Dialum guineense. The results indicate that all the extracts inhibited the corrosion process in the medium by virtue of adsorption and inhibition efficiency improved with concentration.

L. A. Nnanna; B. N. Onwuagba; I. M. Mejeha; K. B. Okeoma

2010-01-01

412

Fatigue behaviour of FSW and MIG weldments for two aluminium alloys  

Microsoft Academic Search

The increasing use of aluminium alloys in transportation, such as railways, shipbuilding and aeronautics, calls for more efficient and reliable welding processes that would require more in depth understanding of fatigue failure. The objective of this work focuses on the contrasting difference of fatigue behaviour of joints made from the traditional process of metal inert gas (MIG) welding, and the

P. M. G. P. Moreira; M. A. V. de Figueiredo

2007-01-01

413

Numerical simulation study of laser-driven shock wave propagation in planar aluminium foils  

Microsoft Academic Search

A comprehensive numerical simulation study of laser-driven shock wave propagation in planar aluminium foils, 20– 50? m, is performed using the one-dimensional radiation hydrodynamic code MULTI. The effect of the spatial mesh size on the shock velocity and peak shock pressure is found to be significant and the optimum mesh size is obtained. Shock velocities and maximum pressure are calculated

V K Senecha; Jie Zhang; Wie Wang; H C Pant

2002-01-01

414

The British aluminium industry, 1945-80s: chronicles of a death foretold?  

Microsoft Academic Search

The paper aims to give an overview of the evolution of the British aluminium industry after 1945. Its objective is to analyse the national character of the sector's evolution over the post-war period. The case seems to illustrate the so-called British economic 'failure' often quoted by economic historians writing about the period (Jones, 1997). Nevertheless, geographical, financial, managerial and cultural

Ludovic Cailluet

2001-01-01

415

The thermal conductivity of plasma electrolytic oxide coatings on aluminium and magnesium  

Microsoft Academic Search

Plasma electrolytic oxide coatings have been produced on both aluminium and magnesium substrates. Their microstructures have been studied and deductions made about formation conditions. The thermal conductivities of the coatings have been measured using a simple steady state method. The values obtained are relatively low (?1 W m?1 K?1). This is explained in terms of the microstructure, which exhibits an

J. A. Curran; T. W. Clyne

2005-01-01

416

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

E-print Network

A composite cement is a hydraulic cement composed of Portland cement and one or more inorganic materials products have any effects on the cement durability and phases formed in cement. Current work has involvedCorrosion of Aluminium in Composite Cements Anthony Setiadi* and Neil B. Milestone Immobilisation

Sheffield, University of

417

Aluminium substitution in iron(II III)-layered double hydroxides: Formation and cationic order  

NASA Astrophysics Data System (ADS)

The formation and the modifications of the structural properties of an aluminium-substituted iron(II-III)-layered double hydroxide (LDH) of formula Fe4IIFe(2-6y)IIIAl6yIII (OH) 12 SO 4, 8H 2O are followed by pH titration curves, Mössbauer spectroscopy and high-resolution X-ray powder diffraction using synchrotron radiation. Rietveld refinements allow to build a structural model for hydroxysulphate green rust, GR(SO 42-), i.e. y=0, in which a bilayer of sulphate anions points to the Fe 3+ species. A cationic order is proposed to occur in both GR(SO 42-) and aluminium-substituted hydroxysulphate green rust when y<0.08. Variation of the cell parameters and a sharp decrease in average crystal size and anisotropy are detected for an aluminium content as low as y=0.01. The formation of Al-GR(SO 42-) is preceded by the successive precipitation of Fe III and Al III (oxy)hydroxides. Adsorption of more soluble Al III species onto the initially formed ferric oxyhydroxide may be responsible for this slowdown of crystal growth. Therefore, the insertion of low aluminium amount ( y˜0.01) could be an interesting way for increasing the surface reactivity of iron(II-III) LDH that maintains constant the quantity of the reactive Fe II species of the material.

Ruby, Christian; Abdelmoula, Mustapha; Aissa, Rabha; Medjahdi, Ghouti; Brunelli, Michela; François, Michel

2008-09-01

418

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

419

Lanthanide compounds as environmentally-friendly corrosion inhibitors of aluminium alloys: a review  

Microsoft Academic Search

Currently, chromates are among the most common substances used as inhibitors or incorporated in anticorrosive pretreatments of aluminium alloys. However, these compounds are highly toxic and their use produces serious environmental hazards. Consequently, an intense research effort is being undertaken to replace chromates by more ecological compounds. In recent years, several authors have begun studies of the behaviour of lanthanide

M. Bethencourt; F. J. Botana; J. J. Calvino; M. Marcos; M. A. RodrÍguez-Chacón

1998-01-01

420

Effect of root hair length on aluminium tolerance in white clover  

Microsoft Academic Search

The aluminium (Al) tolerance of white clover (Trifolium repens L.) lines that had either long or short root hair lengths were evaluated in low ionic strength (2.7 x 10 M) solution culture. Absolute yield of the long root hair length plants was greater than the short root hair length plants at all Al rates by, on average, 34%. However, increasing

D. M. Wheeler

1995-01-01

421

The application of X-ray topography to the study of fatigued aluminium  

Microsoft Academic Search

The Berg-Barrett technique of x-ray topography has been applied to fatigued aluminium single crystals. It has been demonstrated that the technique is successful in revealing persistent slip bands. The mechanism of contrast within the bands is discussed.

D G Teer; G D Brown

1970-01-01

422

Spectrofluorimetric determination of aluminium using 2-hydroxy-1-naphthylidene-(8-aminoquinoline).  

PubMed

A sensitive and selective spectrofluorimetric method has been developed for the rapid determination of aluminium. This method is based on the complex formation between aluminium and 2-hydroxy-1-naphthylidene-(8-aminoquinoline) (HNAQ). The optimum conditions for the complex formation were a metal-to-ligand (M : L) stoichiometric ratio of 1:1, a pH of 5.5 and a 0.20 m acetate buffer. The fluorescence of the complex was monitored at an emission wavelength of 502 nm with excitation at 438 nm. Under these conditions, linear calibration curves were obtained in the ranges 0.05-1 and 1-5 ppm. The detection limit was 3.4 ppb for the former and 13.5 ppb for the latter. The maximum relative standard deviation of the method for an aluminium standard of 200 ppb was 1.5% (n = 5). This method was successfully applied for the determination of aluminium in drinking water, pharmaceutical antacid tablets and suspension samples. PMID:20960575

Al-Kindy, Salma M Z; Al-Mafrigi, Zahra; Shongwe, Musa S; Suliman, Fakhr Eldin O

2011-01-01

423

Effect of electron irradiation on creep and dislocation structure of aluminium  

Microsoft Academic Search

The effect of electron irradiation and strain on structure of technical-purity aluminium subjected to constant-load tensile creep tests was investigated. The dislocation structure was statistically analyzed. The effect of electron irradiation appears in the creep rate reduction and generation of radiation defect clusters, the density of which is approximately proportional to the dose. The effect on the dislocation distribution is

L. I. Ivanov; A. Orlová; V. M. Lazorenko; O. V. Martishin

1979-01-01

424

FEA & Experiments in Aluminium Butt Cold Welding Case - Mechanically Affected Zone Description  

Microsoft Academic Search

The paper presents several theoretical and experimental results regarding the deformation process in butt cold welding case of Aluminium bars. The approach is based on a finite element model capable to predict the material behaviour during the up-setting, considering several constrains introduced by the FEA code: non-linear static analysis, large strain and large deflection, prescribed displacements. The theoretical data obtained

Mihaela Iordachescu; Elena Scutelnicu; Bogdan Georgescu

425

Statistical analysis of optimum friction welding conditions for 6061 aluminium alloy friction-welded joints  

Microsoft Academic Search

Conferring lightweight and good corrosion resistance, aluminium alloy joints are extensively required in the manufacture of various types of electrical and mechanical components. Research data previously obtained by the authors show the efficiency of friction-welded joints, regardless of whether produced from similar or dissimilar materials, to be fairly well scattered under identical sets of friction welding conditions and underline the

R. Tsujino; G. Kawai; H. Ochi; H. Yamaguchi; K. Ogawa; Y. Yamamoto

2005-01-01

426

Electrodeposition and characterization of polypyrrole films on aluminium alloy 6061-T6  

Microsoft Academic Search

Polypyrrole films on aluminium alloy 6061-T6 were prepared by electropolymerization of pyrrole in sulphuric acid using two different processes – cyclic voltammetry and potentiostatic polarization – and assessed through SEM observation and voltammetry. The anticorrosive properties of these films were studied by polarization curves and electrochemical impedance spectroscopy.The polypyrrole films formed by both methods are homogeneous and present a globular

N. C. T. Martins; T. Moura e Silva; M. F. Montemor; J. C. S. Fernandes; M. G. S. Ferreira

2008-01-01

427

Hepatic clearance and retention of aluminium: studies in the isolated perfused rat liver  

Microsoft Academic Search

Aluminium (Al) exposure can result in Al accumulation in the liver and this metal can be toxic to the hepatic tissue at high concentrations. In the present study the model of the isolated perfused rat liver was used to investigate the hepatic handling of Al. Livers from male Wistar rats were perfused in a recirculating system for 240 min. The

Michael Whihelm; Daphne E. Jaeger; Heike Schüll-Cablitz; Dieter Hafner; Helga Idel

1996-01-01

428

An experimental study of the recrystallization mechanism during hot deformation of aluminium  

Microsoft Academic Search

Discontinuous dynamic recrystallization (involving nucleation and grain growth) is rarely observed in metals with high stacking fault energies, such as aluminium. In this metal, two other types of recrystallization have been observed: continuous dynamic recrystallization (CDRX, i.e. the transformation of subgrains into grains); and geometric dynamic recrystallization (due to the evolution of the initial grains). The main purpose of this

S Gourdet; F Montheillet

2000-01-01

429

Workability of aluminium-based metal-matrix composites in cold compression  

Microsoft Academic Search

Cold compression tests have been carried out on aluminium-based metal-matrix composite (MMC) materials. Metallographic examinations have revealed very large local plastic flow in the matrix material subjected to compressive loading. It is found that localized shear flow of the matrix may control the failure of the composite under compression. A new processing technique has been developed and the cold workability

J. Jiang; B. Dodd

1995-01-01

430

The effect of aluminium on NTPDase and 5?-nucleotidase activities from rat synaptosomes and platelets  

Microsoft Academic Search

Aluminium (Al), a neurotoxic compound, has been investigated in a large number of studies both in vivo and in vitro. In this study, we investigated the effect in vivo of long-term exposure to Al on NTPDase (nucleoside triphosphate diphosphohydrolase) and 5?-nucleotidase activities in the synaptosomes (obtained from the cerebral cortex and hippocampus) and platelets of rats. Here, we investigated a

Rosilene Rodrigues Kaizer; Paula Acosta Maldonado; Rosélia Maria Spanevello; Maísa C. Corrêa; Jamile F. Gonçalves; Lara Vargas Becker; Vera Maria Morsch; Maria Rosa Chitolina Schetinger

2007-01-01

431

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

432

EFFECTS OF ALUMINIUM (Al 3+ ) ON SEED GERMINATION AND SEEDLING GROWTH OF WHEAT (TRITICUM AESTIVUM L.)  

Microsoft Academic Search

Effects of different concentrations of aluminium (Al 3+ ) on seed germination of high yielding varieties of wheat (Triticum aestivum L.) were investigated. Al 3+ at 500 ppm had inhibitory effect on seed germination, seedling growth and its dry matter. Relatively higher root and shoot dry matter in Sonlika, Fang-60 and lower in Baw-923 and Protiva were found. Root growth

A. N. M. ALAMGIR; SUFIA AKHTER

2009-01-01

433

Dynamic and quasi-static deformation of aluminium honeycomb sandwich panel in three point bending  

Microsoft Academic Search

In this research, the dynamic and quasi-static deformations of aluminium honeycomb sandwich panels in three point bending were investigated experimentally. The load, the deflection of a loading point and the strain response of the rear surface plate at various locations were measured. A peak load caused by local plastic buckling of the cores just under the loading point appeared in

H. Kobayashi; M. Daimaruya; Y. Takaya

2003-01-01

434

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

435

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

E-print Network

High cycle fatigue damage mechanisms in cast aluminium subject to complex loads Imade Koutiria to the high cycle fatigue behaviour of cast hypo-eutectic Al­Si alloys. In particular, the AlSi7Cu05Mg03 alloy is investigated. It presents the results of a vast experimental campaign undertaken to investigate the fatigue

Paris-Sud XI, Université de

436

Modelling the environmental impact of an aluminium pressure die casting plant and options for control  

Microsoft Academic Search

This study describes a model (MIKADO) to analyse options to reduce the environmental impact of aluminium die casting. This model will take a company perspective, so that it can be used as a decision-support tool for the environmental management of a plant. MIKADO can be used to perform scenario analyses to analyse the impact on the environment of different strategies,

Belmira Neto; Carolien Kroeze; Leen Hordijk; Carlos Costa

2008-01-01

437

Application of hard coatings in aluminium die casting — soldering, erosion and thermal fatigue behaviour  

Microsoft Academic Search

In aluminium die casting, tools are exposed to erosion, corrosion and soldering due to the frequent contact of the tool surface to the casting alloy, to heat checking and gross cracking due to thermal fatigue and to oxidation due to high pouring temperatures. The gradual destruction of die surfaces during service decreases casting piece quality and limits die lifetime. Hard

C Mitterer; F Holler; F Üstel; D Heim

2000-01-01

438

Laboratory investigation of the phosphorus removal (SRP and TP) from eutrophic lake water treated with aluminium  

Microsoft Academic Search

Mechanisms involved in phosphorus (P) removal from eutrophic lake water with aluminium (Al) were assessed by jar tests. For this purpose, eutrophic lake water enriched with soluble reactive phosphorus (SRP), algae or sediments in order to mimic the various conditions found in shallow eutrophic lakes was studied. Total phosphorus (TP) removal was reached after floc settling, the maximal TP removal

Franck Auvray; Eric D. van Hullebusch; Veronique Deluchat; Michel Baudu

2006-01-01

439

The geology of aluminium phosphates and sulphates of the alunite group minerals: a review  

Microsoft Academic Search

Aluminium phosphates and sulphates of the alunite supergroup (APS minerals) occur in a wide range of environments of formation covering the metamorphic, igneous and sedimentary realms. Supergene processes, including mineral dressing and dumping when sulphide ores are mined, as well as hypogene alteration are also responsible for the precipitation of APS minerals. In these environments, complex solid solution series (s.s.s.)

Harald G Dill

2001-01-01

440

Extrusion of zeolites: Properties of catalysts with a novel aluminium phosphate sintermatrix  

Microsoft Academic Search

A novel type of mechanically strong zeolite extrudates is introduced, in which the zeolite crystals, here ZSM-5, are embedded in a sintermatrix of aluminium phosphate with the crystal structure of tridymite. The pore size distribution in the matrix can be tailored through both, the choice of the size of the embedded particles and their amount in the extrudates. At zeolite

Jens Freiding; Florina-Corina Patcas; Bettina Kraushaar-Czarnetzki

2007-01-01

441

Residual stresses in aluminium phosphate sealed plasma sprayed oxide coatings and their effect on abrasive wear  

Microsoft Academic Search

Effect of residual stresses on plasma sprayed alumina and chromia coatings sealed with aluminium phosphate were studied as a function of the temperature of the sealing treatment. Stresses were measured by X-ray stress analysis and high-speed circular microhole drilling method. Residual stress states were correlated with other coating properties such as microhardness, porosity, microstructure and dry abrasion wear resistance. Correlations

S. Ahmaniemi; M. Vippola; P. Vuoristo; T. Mäntylä; M. Buchmann; R. Gadow

2002-01-01

442

The role of added water in the ionothermal synthesis of microporous aluminium phosphates  

Microsoft Academic Search

Water plays an important role in ionothermal synthesis and it has been suggested that it can influence phase selection. We have carried out an extensive study to determine the phases produced at various ratios of water to ionic liquid in the microwave assisted ionothermal synthesis of fluorinated aluminium phosphate frameworks using 1-ethyl-3-methylimidazolium bromide and 1-ethylpyridinium bromide. Aluminophosphate chabazite is the

David S. Wragg; Alexandra M. Z. Slawin; Russell E. Morris

2009-01-01

443

Effect of aluminium phosphate on the bioavailability of cimetidine and prednisolone  

Microsoft Academic Search

Ten fasting subjects received 200 mg cimetidine orally either with water or 11 g aluminium phosphate mixture in a randomized, single dose, two-way cross-over study. Blood samples were taken for 12 h and urine was collected for 24 h. Cimetidine in plasma and urine was analysed by HPLC. There were no significant differences between the treatments with respect to peak

H. Albin; G. Vinçon; F. Demotes-Mainard; B. Begaud; A. Bedjaoui

1984-01-01

444

Scatter bands summarizing the fatigue strength of aluminium alloy bolted joints  

Microsoft Academic Search

A large number of geometrical, technological and environmental factors theoretically influence the fatigue behaviour and the failure modes of the bolted joints. In order to make clear the influence of some of such variables, in this work over one hundred aluminium symmetric double butt joints were tested, subdivided into eight series, with the purpose to compare their fatigue properties and

P. Lazzarin; V. Milani; M. Quaresimin

1997-01-01

445

Low temperature synthesis of aluminium titanate by an aqueous sol–gel route  

Microsoft Academic Search

Formation of aluminium titanate (AT) has been achieved at low temperature through sol–gel process using boehmite and titanium hydroxide as precursors by controlling the particle size at nanoscale followed by in-situ peptisation. The formations of AT phase, particle size distributions, sintering and thermal expansion characteristics, and microstructural features have been reported. DTA and XRD analysis have been performed to confirm

M. Jayasankar; S. Ananthakumar; P. Mukundan; K. G. K. Warrier

2007-01-01

446

Monohydroxy aluminium oxide (Boehmite, AlOOH) as a reactive binder for extrusion of alumina ceramics  

Microsoft Academic Search

Monohydroxy aluminium oxide (Boehmite, AlOOH) has been used as an extrusion aid along with ?-alumina and ?-alumina particulates. Extended ball milling of the mixture using alumina grinding media imparts nucleating seeds to boehmite for an early conversion to ?-alumina. The boehmite-?-alumina mixture appears to result in a denser alumina ceramic accompanied by an enhanced grain growth indicating the higher reactivity

C. Sunil Kumar; A. D. Damodaran; K. G. K. Warrier

1997-01-01

447

A friction effect in low-load hardness testing of copper and aluminium  

Microsoft Academic Search

Vickers hardness tests were conducted on samples of copper and aluminium in a cold rolled or annealed condition to determine the apparent hardness variation in the load range 15 g to 20 kg. The variation was greatest for the soft specimens. Lubrication with an extreme-pressure lubricant was effective in reducing the hardness values to a virtually constant level for each

H. Shi; M. Atkinson

1990-01-01

448

Fatigue behaviour of post weld heat treated electron beam welded AA2219 aluminium alloy joints  

Microsoft Academic Search

This paper reports the effect of post weld heat treatment on fatigue behaviour of electron beam welded AA2219 aluminium alloy. An attempt has been made to enhance the fatigue strength of the electron beam welded joints through post weld heat treatment methods such as solution treatment, artificial aging, solution treatment and artificial aging. Electron beam welding machine with 100kV capacity

S. Malarvizhi; K. Raghukandan; N. Viswanathan

2008-01-01

449

The improvement of aluminium casting process control by application of the new CRIMSON process  

Microsoft Academic Search

All The traditional foundry usually not only uses batch melting where the aluminium alloys are melted and held in a furnace for long time, but also uses the gravity filling method in both Sand Casting Process (SCP) and Investment Casting Process (ICP). In the gravity filling operation, the turbulent behaviour of the liquid metal causes substantial entrainment of the surface

X Dai; M Jolly; B Zeng

2012-01-01

450

Effect of Plasma Electrolytic Oxidation coating on the specific strength of open-cell aluminium foams  

Microsoft Academic Search

Plasma Electrolytic Oxidation (PEO) coating treatment is applied to open celled aluminium foams with different structures, aiming to enhance the mechanical performance of the composite material. The mechanical properties of the coated foams produced are assessed experimentally, both in tension and compression. From experimental results, yield stress is found to increase initially with increasing PEO coating thickness, though this trend

T. Abdulla; A. Yerokhin; R. Goodall

2011-01-01

451

AC impedance-emission spectroscopy for determining the electrochemical behaviour of anodised aluminium in aqueous solutions  

Microsoft Academic Search

In the present investigation, holographic interferometry was utilised for the first time to determine the rate change of the alternating current (AC) impedance of aluminium samples during the initial stage of anodisation processes in aqueous solution without any physical contact. In fact, because the AC impedance values in this investigation were obtained by holographic interferometry, electromagnetic method rather than electronic

K. Habib

2010-01-01

452

Comparative Study of 3D Printing Technologies for Rapid Casting of Aluminium Alloy  

Microsoft Academic Search

The purpose of this study is to compare the efficacy of two rapid casting technologies, namely, ZCast process and investment casting based on 3D printing technique of rapid prototyping for casting of aluminium alloy. A standard procedure has been premeditated starting from the identification and design of benchmark. The concept was presented in physical form by producing prototypes to assess

Simranpreet Singh Gill; Munish Kaplas

2009-01-01

453

??????????????????????????????????????????????????? 6063 ??????????????????????? ???????? MICROSTRUCTURES AND MECHANICAL PROPERTIES OF HEAT TREATED ALUMINIUM ALLOY 6063 ??????? ???????1, ??????????? ??????????1 ??? ??????? ???????????? 1  

Microsoft Academic Search

????????: ?????????????????????? 6063 ??????????????????????????????????????????? ????????????????????? 0.44 ?????????? 0.43 ??? ??????????? 98.53 ?????????????????????? ???????????????????????????? 1×1×0.5 ????????????????? ??????????? 560 ???????????? 15 ???? ????????????? ?????????????????? 150 200 ??? 240 ???????????? ???????????? ? ??? ??? 1 ??? 72 ??????? ???????????????????????????????????????????????????????? ????????????????? 99 HV ????????????????????????? ? ???????? 200 ???????????? ??? 25 ??????? Abstract: The aluminium alloy 6063 billet used in this study composes of 98.53%

Kanokwan Uttarasak; Sukunthakan Ngernbamrung; Narin Sirikulrat

454

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

455

Zinc protection against aluminium induced altered lipid profile and membrane integrity.  

PubMed

The aim of the present study was to investigate the effects of Zinc (Zn) supplementation on lipid profile and fluidity of cerebrum and cerebellum membranes of rats treated with aluminium (Al). Sprague dawley male rats were divided into four different treatment groups viz: Control, aluminium treated, zinc treated and aluminium+zinc treated. Aluminium (AlCl3) was administered orally at a dose of 100mg/kgb.wt./day (dissolved in drinking water). Zinc as zinc sulphate was supplemented to rats at a dose of 227mg/l in drinking water. A significant decrease in the levels of total lipids, glycolipids, phospholipids, cholesterol and gangliosides contents were observed in both the cerebrum and cerebellum following Al exposure, which were found to be significantly increased following Zn supplementation. On the contrary, Al treatment caused a significant increase in the formation of conjugated dienes, which were observed to be reduced on Zn co-treatment. Further, Al treatment significantly elevated the fluorescence polarization, anisotropy and order parameter, which however were normalized upon Zn co-administration. Hence, the present study depicts the potential of Zn in moderating the changes caused by Al on membrane composition and fluidity in rat brain. PMID:23313339

Singla, Neha; Dhawan, D K

2013-05-01

456

Aluminium as a risk factor in Alzheimer’s disease, with emphasis on drinking water  

Microsoft Academic Search

Aluminium (Al) is clearly a powerful neurotoxicant. Considerable evidence exists that Al may play a role in the aetiology or pathogenesis of Alzheimer’s disease (AD), but whether the link is causal is still open to debate. This paper reviews the epidemiological evidence linking Al and AD. Nine out of 13 published epidemiological studies of Al in drinking water and AD

Trond Peder Flaten

2001-01-01

457

Finite element analysis of effect of electrode pitting in resistance spot welding of aluminium alloy  

Microsoft Academic Search

The effect of electrode pitting on the formation of the weld nugget in resistance spot welding of an aluminium alloy was investigated using the finite element method. Pitted electrodes were simulated by assuming a pre-drilled hole of varying diameter at the centre of the electrode tip surface. The results showed that a small pitting hole would not have a detrimental

B. H. Chang; Y. Zhou; I. Lum; D. Du

2005-01-01

458

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

459

Influence of Hysteretic Behaviour in Reactive Magnetron Sputtering on the Crystal Structure and Characteristics of Aluminium Oxide Films  

NASA Astrophysics Data System (ADS)

The influence of the hysteretic behaviour in reactive sputtering with a pure aluminium target in the presence of argon and oxygen plasma on transmittance and surface free energy of aluminium oxide films was investigated by plasma optical emission spectroscopy technology. The evolutions of aluminium, and aluminium oxide emission lines as functions of oxygen flow rate at constant power and pressure were studied. A steep transition from the metallic sputtering to the compound sputtering was observed upon increasing the oxygen flow rate from 0.0 SCCM to above 2.0 SCCM. Then an optimal deposition zone was obtained through analyzing the hysteretic curves of aluminium and aluminium oxide emission lines. The evolution of crystal structures of samples was discerned by X-ray diffraction spectra data. Energy dispersive X-ray spectroscopy data also demonstrate the relationship between the chemical compositions of aluminium oxide films and the hysteretic behaviour. The film deposited between 1.5 SCCM and 2.0 SCCM oxygen flow rate displays an optimal and stoichiometic atomic ratio of O to Al and mass ratio of O to Al. The changes in the transmittance of samples were discovered to depend on the oxygen flow rate by UV-VIS transmittance spectra, and the changes in surface free energy were studied by contact angle measurement.

Wang, Qing; Yue, Xiangji; Ba, Dechun; Zhang, Yichen; Chen, Caihong

2013-08-01

460

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

461

Additions to Neotropical Chrysobalanaceae  

Microsoft Academic Search

A study of collections of Chrysobalanaceae provides range extensions of some species and additional information for a few\\u000a poorly known ones. Ten new species are here described and illustrated:Licania cabrerae, L. montana, L. morii, L. jefensis, L. pakaraimensis, L. marlenei, L. stewardii, L. aracaensis, Hirtella\\u000a arenosa, H. conduplicata. Several of these are from high elevations, showing that the family is

Ghillean T. Prance

1976-01-01

462

Almost additive entropy  

E-print Network

We explore consequences of a hyperbolic metric induced by the composition property of the Harvda-Charvat/Dar\\'{o}czy/Cressie-Read/Tsallis entropy. We address the special case of systems described by small deviations of the non-extensive parameter \\ $q\\approx 1$ \\ from the "ordinary" additive case which is described by the Boltzmann/Gibbs/Shannon entropy. By applying the Gromov/Ruh theorem for almost flat manifolds, we show that such systems have a power-law rate of expansion of their configuration/phase space volume. We explore the possible physical significance of some geometric and topological results of this approach.

Nikos Kalogeropoulos

2014-01-06

463

3.OA Addition Patterns  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: Below is a table showing addition of numbers from $1$ through $5$. In each column and each row of the table, even and odd numbers alternate. Explain wh...

464

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

465

THE MODIFICATION OF ALUMINIUM-SILICON ALLOYS BY SODIUM  

Microsoft Academic Search

Measurements by autoradiography and activation analysis have revealed ; the distribution of sodium in the microstructures of aluminum --7.5% silicon ; alloys modified by the addition of various amounts of sodium. ; Electronmicroscopic studies indicate that there is no fundamental difference ; between modication by chill casting and modification by sodium addition. A ; previously unobserved submicroscopic phase, the amount

R. C. Plumb; J. E. Lewis

1958-01-01

466

Proppant flowback control additives  

SciTech Connect

This paper describes the laboratory and field development of thermoplastic film materials used to reduce proppant flowback that can occur after fracturing treatments. The paper provides a summary of flowback mechanism theories and laboratory tests comparing flowback tendency for various types of treating procedures and materials. Some of these materials include angular proppant, proppant/fiber mixtures, and proppant with film strips tested over a wide range of temperature, closure stress, and flow-rate conditions. Field treatment procedures are discussed, and several case histories are presented. All of the methods evaluated were effective in reducing proppant flowback under certain conditions. Heat-shrink film cut into thin slivers proved to provide flowback reduction over broad temperature and closure stress ranges and was found to cause little impairment to fracture conductivity with some dependency on use concentration, temperature, and closure stress. The film materials were more resistant to damage caused by blending and pumping than all other materials evaluated. In addition, proppant packs, including consolidated packs, were significantly more tolerant of large, repeated stress changes. Field results indicate that the use of the heat-shrink film material as a flowback control agent permits more aggressive bean-up procedures following conventional fracturing treatments. Conventional dry-additive metering systems were used to add the film material to the fracturing fluid proppant slurry.

Nguyen, P.D.; Weaver, J.D.; Parker, M.A. [and others

1996-12-31

467

New addition curing polyimides  

NASA Technical Reports Server (NTRS)

In an attempt to improve the thermal-oxidative stability (TOS) of PMR-type polymers, the use of 1,4-phenylenebis (phenylmaleic anhydride) PPMA, was evaluated. Two series of nadic end-capped addition curing polyimides were prepared by imidizing PPMA with either 4,4'-methylene dianiline or p-phenylenediamine. The first resulted in improved solubility and increased resin flow while the latter yielded a compression molded neat resin sample with a T(sub g) of 408 C, close to 70 C higher than PME-15. The performance of these materials in long term weight loss studies was below that of PMR-15, independent of post-cure conditions. These results can be rationalized in terms of the thermal lability of the pendant phenyl groups and the incomplete imidization of the sterically congested PPMA. The preparation of model compounds as well as future research directions are discussed.

Frimer, Aryeh A.; Cavano, Paul

1991-01-01

468

Lubricating oil additives  

SciTech Connect

What is disclosed is a concentrated polymer emulsion useful as a lubricating oil additive for improving the viscosity index thereof, said emulsion comprising: (1) a dispersed phase of an olefinic copolymer having a molecular weight complementary with respect to the thickening effect desired; (2) a dispersing phase of a polymer predominantly comprising at least one member selected from the group consisting of acrylate ester and methacrylate ester monomers; (3) a vehicle which is a good solvent for the esters in said dispersing phase and a substantially less good solvent for the olefinic copolymer by virtue of the esters dissolved in said vehicle; and (4) an emulsifier, stabilizing phase distribution, which is a member selected from the group consisting of graft copolymers and block copolymers formed from olefinic monomers and at least one member selected from the group consisting of acrylate ester and methacrylate ester monomers.

Benda, R.; Jost, H.; Knoell, H.; Pennewiss, H.

1981-09-22

469

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

470

The partial space qualification of a vertically aligned carbon nanotube coating on aluminium substrates for EO applications.  

PubMed

The fabrication of NanoTube Black, a Vertically Aligned carbon NanoTube Array (VANTA) on aluminium substrates is reported for the first time. The coating on aluminium was realised using a process that employs top down thermal radiation to assist growth, enabling deposition at temperatures below the substrate's melting point. The NanoTube Black coatings were shown to exhibit directional hemispherical reflectance values of typically less than 1% across wavelengths in the 2.5 µm to 15 µm range. VANTA-coated aluminium substrates were subjected to space qualification testing (mass loss, outgassing, shock, vibration and temperature cycling) before their optical properties were re-assessed. Within measurement uncertainty, no changes to hemispherical reflectance were detected, confirming that NanoTube Black coatings on aluminium are good candidates for Earth Observation (EO) applications. PMID:24664077

Theocharous, Evangelos; Chunnilall, Christopher J; Mole, Ryan; Gibbs, David; Fox, Nigel; Shang, Naigui; Howlett, Guy; Jensen, Ben; Taylor, Rosie; Reveles, Juan R; Harris, Oliver B; Ahmed, Naseer

2014-03-24

471

Constitutive Laws for Steady State Deformation of Metals, a Microstructural Model with Applications to Hot Deformation of Aluminium Alloys (Revised).  

National Technical Information Service (NTIS)

Papers submitted for publication in Scripta Metall. & Mater: Constitutive laws for steady state deformation of metals, a microstructural model; Application of microstructurally based constitutive laws to hot deformation of aluminium alloys.

E. Nes, T. Furu

1994-01-01

472

Perforation of AA5083-H116 aluminium plates with conical-nose steel projectiles—experimental study  

Microsoft Academic Search

The interest regarding use of aluminium alloys in lightweight protective structures is today increasing. Even so, the number of experimental and computational investigations giving detailed information on such problems is still rather limited. In this paper, perforation experiments have been performed on AA5083-H116 aluminium plates with thicknesses varying between 15 and 30mm impacted by 20mm diameter, 98mm long, HRC 53

Tore Børvik; Arild H. Clausen; Odd Sture Hopperstad; Magnus Langseth

2004-01-01

473

Preparation and properties of transparent conducting zinc oxide and aluminium-doped zinc oxide films prepared by evaporating method  

Microsoft Academic Search

Undoped and aluminium-doped zinc oxide films have been prepared by thermal evaporation of zinc acetate [Zn(CH3COO)2 2H2O] and aluminium chloride [AlCl3] onto a heated glass substrate. The structural and optoelectrical properties of the films have been studied. The effects of heat treatment for the as-deposited films in air and vaccum are investigated. Highly transparent films with conductivity as low as

Jin Ma; Feng Ji; Hong-lei Ma; Shu-ying Li

2000-01-01

474

Solid–solid interactions in Fe 2O 3\\/MgO system doped with aluminium and zinc oxides  

Microsoft Academic Search

The solid–solid interactions between MgO and Fe2O3 in the presence and absence of small amounts of Al2O3 and ZnO (2 and 6mol%) have been investigated using DTA and XRD techniques. Equimolar proportions of magnesium basic carbonate and ?-Fe2O3 were employed and aluminium and zinc were added as aluminium and zinc nitrates. Pure and doped mixed solids were subjected to heat

G. A El-Shobaky; A. A Mostafa

2003-01-01

475

Effect of Tool Pin Profile and Tool Rotational Speed on Mechanical Properties of Friction Stir Welded AA6061 Aluminium Alloy  

Microsoft Academic Search

AA6061 aluminium alloy (Al-Mg-Si alloy) has gathered wide acceptance in the fabrication of light weight structures requiring a high strength-to-weight ratio and good corrosion resistance. Compared to many of the fusion welding processes that are routinely used for joining structural aluminium alloys, the Friction Stir Welding (FSW) process is an emerging solid state joining process in which the material that

K. Elangovan; V. Balasubramanian; M. Valliappan

2008-01-01

476

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

477

The Influence of Finite Geometry and Material Properties on Mixed-Mode I\\/II Fracture of Aluminium  

Microsoft Academic Search

Numerical calculations have been carried out to assess the influence of both finite geometry effects as well as material properties\\u000a on mixed mode fracture of aluminium. These effects have been studied in close connection to experimental data for two aluminium\\u000a alloys found in the literature. Interactions between the crack tip and the outer boundary have, for one of these alloys,

N. Hallbäck

1997-01-01

478

The Constitution of the Copper-Rich Copper-Aluminium-Tin Alloys, with Special Reference to Ternary Compound Formation  

Microsoft Academic Search

The constitution of copper-rich copper-aluminium-tin alloys has been examined by metallographic and X-ray methods in order to investigate the nature of a suspected ternary phase stable at temperatures below that of the eutectoid decomposition in the copper-aluminium system. The existence of a ternary phase T has been established, and isothermal diagrams have been established at various temperatures between 650 and

J. S. L. Leach; G. V. Raynor

1954-01-01

479

Rapid extraction separation of aluminium(III) from associated elements with n-octylaniline from succinate media  

Microsoft Academic Search

In this study, n-octylaniline (2% (v\\/v) in toluene) ligand was used in the solvent extraction of aluminium(III) from aqueous succinate media (0.04M). The distribution coefficient and distribution ratio were determined as a function of aluminium(III) concentration in the aqueous phase and extractant concentration in the organic phase. It was found that pH does not affect the metal extraction process in

T. N. Shilimkar; S. S. Kolekar; M. A. Anuse

2005-01-01

480

Protective Role of Lithium in Ameliorating the Aluminium-induced Oxidative Stress and Histological Changes in Rat Brain  

Microsoft Academic Search

This study was carried out to investigate the effects of lithium (Li) supplementation on aluminium (Al) induced changes in\\u000a antioxidant defence system and histoarchitecture of cerebrum and cerebellum in rats. Al was administered in the form of aluminium\\u000a chloride (100 mg\\/kg b.wt.\\/day, orally) and Li was given in the form of Li carbonate through diet (1.1 g\\/kg diet, daily) for\\u000a a period

Punita Bhalla; D. K. Dhawan

2009-01-01

481

paisses d'aluminium, on remarque qu'il faut une certaine paisseur de mtal pour arrter complte-  

E-print Network

14 épaisses d'aluminium, on remarque qu'il faut une certaine épaisseur de métal pour arrêter teinte formé par les deux prismes en aluminium C dont nous venons de parler, et d'observer les deux'oxyde d'uranium) se montrait quatre fois plus active que l'uranium métallique; la chalcolite (phosphate

Paris-Sud XI, Université de

482

Influence of composition and of activation temperature upon the adsorption and thermodesorption of ammonia on aluminium oxide-silica gels  

Microsoft Academic Search

Aluminium oxide gel and aluminium oxide-silica gels of different compositions were prepared and activated at different temperatures. The adsorption of NH3 was studied in a McBain type balance at 20 torr and 5×10?3 torr at 25°. The thermodesorption of NH3 was studied at 5×10?3 torr between 25 and 550° at a constant heating rate of 4°\\/min. The desorption was followed

A. Pop; P. Kröbl; P. Jozsa

1972-01-01

483

Ceramics with Different Additives  

NASA Astrophysics Data System (ADS)

Li2CO3, MgCO3, BaCO3, and Bi2O3 dopants were introduced into CaCu3Ti4O12 (CCTO) ceramics in order to improve the dielectric properties. The CCTO ceramics were prepared by conventional solid-state reaction method. The phase structure, microstructure, and dielectric behavior were carefully investigated. The pure structure without any impurity phases can be confirmed by the x-ray diffraction patterns. Scanning Electron Microscopy (SEM) analysis illuminated that the grains of Ca0.90Li0.20Cu3Ti4O12 ceramics were greater than that of pure CCTO. It was important for the properties of the CCTO ceramics to study the additives in complex impedance spectroscopy. It was found that the Ca0.90Li0.20Cu3Ti4O12 ceramics had the higher permittivity (>45000), the lower dielectric loss (<0.025) than those of CCTO at 1 kHz at room temperature and good temperature stability from -30 to 75 °C.

Wang, Juanjuan; Feng, Lajun; Lei, Ali; Zhao, Kang; Yan, Aijun

2014-09-01

484

Spectrophotometric determination of aluminium and indium with 2,2',3,4-tetrahydroxy-3',5'-disulphoazobenzene.  

PubMed

2,2',3,4-Tetrahydroxy-3',5'-disulphoazobenzene (tetrahydroxyazon 2S) has been synthesized for the first time. This reagent has been used for the spectrophotometric determination of aluminium and indium ions. The method is very sensitive and selective for the direct determination of aluminium and indium. The optimum pH and absorbance of complexes formed of tetrahydroxyazon 2S with aluminium and indium are 5; 500 nm and 495 nm for Al and In, respectively. The system obeys Beer's law at 0.05-1.6 microg mL(-1) of aluminium and 0.06-2.1 microg mL(-1) of indium concentration. The molar absorptivity is 6.42 x 10(4)L mol(-1)cm(-1) for aluminium and 7.70 x 10(4)L mol(-1)cm(-1) for indium. The molar compositions of the complexes are 1:1 at optimum conditions. Alkaline and alkaline earth elements, halogens, thiourea, ascorbic acid, Cd(II), Pb(II), Mn(II), Zn(II), Co(II), Ni(II), Cr(III), Bi(III), La(III), Si(IV) do not interfere this method. The method can be applied to the direct spectrophotometric determination of trace amounts of aluminium in steel, alloys, waste water, river waters, spring water and ground water. The method was also successfully applied to the indium determination in artificial mixture. PMID:18783882

Huseyinli, A A; Alieva, R; Haciyeva, S; Güray, T

2009-04-30

485

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

486

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 ...

Baggaley, Mr.

2008-11-17

487

Aluminium Toxicity in Rye (Secale cereale): Root Growth and Dynamics of Cytoplasmic Ca2+ in Intact Root Tips  

PubMed Central

Aluminium (Al) toxicity in rye (Secale cereale L.), an Al?resistant crop, was examined by measuring root elongation and cytoplasmic free activity of calcium ([Ca2+]cyt) in intact root apical cells. Measurement of [Ca2+]cyt was achieved by loading a Ca2+?sensitive fluorescent probe, Fluo?3/AM ester, into root apical cells followed by detection of intracellular fluorescence using a confocal laser scanning microscope. After 20 min of exposure to 50 µm Al (pH 4·2) a slight increase in [Ca2+]cyt of root apical cells was observed, while the response of [Ca2+]cyt to 100 µm Al (pH 4·2) was faster and larger ([Ca2+]cyt increased by 46 % in 10 min). Increases in [Ca2+]cyt were correlated with inhibition of root growth, generally measurable after 2 h. Addition of 400 µm malic acid (pH 4·2) largely ameliorated the effect of 100 µm Al on [Ca2+]cyt in root apical cells and protected root growth from Al toxicity. These results suggest that an increase in [Ca2+]cyt in root apical cells in rye is an early effect of Al toxicity and is followed by the secondary effect on root elongation. PMID:12099355

MA, QIFU; RENGEL, ZDENKO; KUO, JOHN

2002-01-01

488

Living ring-opening homo- and copolymerisation of ?-caprolactone and L-lactide by cyclic ?-ketiminato aluminium complexes.  

PubMed

A series of novel aluminium complexes containing cyclic ?-ketiminato ligands of type Me2Al{O-[(ArN=CHC4H4(C6H4))]} (3a, Ar = 2,6-(i)Pr2C6H3; 3b, Ar = C6H5; 3c, Ar = C6F5) have been prepared in high yields. These complexes were identified by (1)H, (13)C NMR spectroscopy and elemental analysis. X-ray structural analyses for 3a-c revealed that these complexes have a distorted tetrahedral geometry around Al, and both bond distances and bond angles were considerably influenced by the ligand structure. These complexes were tested as catalyst precursors for ring-opening polymerisation of ?-caprolactone (?-CL) and L-lactide (L-LA) in the presence of 2-propanol as an initiator. Complex 3a could polymerize ?-CL in a controlled manner with high efficiency. Based on the living characteristics, the preparation of well-defined block copolymers PCL-b-PLLA via sequential addition of monomers was performed by 3a. Note that complex 3c exhibited rather high catalytic activity for the ROP of L-LA with narrow molecular weight distribution. The monomer conversion reached completion only in 4 h when the L-LA/Al molar ratio was 100 at 80 °C. PLLA-b-PCL copolymers were thus easily produced by 3c. PMID:24296527

Liu, Yan; Dong, Wei-Shi; Liu, Jing-Yu; Li, Yue-Sheng

2014-02-01

489

Reducing the cost of production of bimetallic aluminium catalysts for the synthesis of cyclic carbonates.  

PubMed

Bimetallic aluminium complexes of general formula [(salen)Al](2)O or [(acen)Al](2)O catalyse the formation of cyclic carbonates from carbon dioxide and terminal epoxides under exceptionally mild reaction conditions. To improve the potential for industrial scale application of these catalysts, the cost of their production has been evaluated and reduced significantly by optimization of the synthesis, including replacement of the most expensive chemicals by less expensive alternatives. The largest cost saving was associated with the formation of aluminium triethoxide in situ, which reduced the cost of the chemicals need for production of the catalysts by 49-87 %. Further savings were made by avoiding the use of tetrabutylammonium bromide and acetonitrile, resulting in overall cost savings of 68-93 %. PMID:22045591

North, Michael; Young, Carl

2011-11-18

490

Comparison of nickel silicide and aluminium ohmic contact metallizations for low-temperature quantum transport measurements.  

PubMed

We examine nickel silicide as a viable ohmic contact metallization for low-temperature, low-magnetic-field transport measurements of atomic-scale devices in silicon. In particular, we compare a nickel silicide metallization with aluminium, a common ohmic contact for silicon devices. Nickel silicide can be formed at the low temperatures (<400°C) required for maintaining atomic precision placement in donor-based devices, and it avoids the complications found with aluminium contacts which become superconducting at cryogenic measurement temperatures. Importantly, we show that the use of nickel silicide as an ohmic contact at low temperatures does not affect the thermal equilibration of carriers nor contribute to hysteresis in a magnetic field. PMID:21968083

Polley, Craig M; Clarke, Warrick R; Simmons, Michelle Y

2011-01-01

491

Fatigue damage rule of LY12CZ aluminium alloy under sequential biaxial loading  

NASA Astrophysics Data System (ADS)

A series of biaxial two-level variable amplitude loading tests are conducted on smooth tubular specimens of LY12CZ aluminium alloy. The loading paths of 90° out-of-phase, 45° out-of-phase and 45° in-phase are utilized. The fatigue damage cumulative rules under two-level step loading of three loading paths are analyzed. By introducing a parameter ? which is a function of the phase lag angle between the axial and the torsional loading, a new multiaxial nonlinear fatigue damage cumulative model is proposed. The proposed model is evaluated by the experimental data for two-level loading, multi-level loading of LY12CZ aluminium alloy, and multi-level loading of 45 steel. Fatigue lives predicted are within a factor of 2 scatter band.

Wang, YingYu; Zhang, DaChuan; Yao, WeiXing

2014-01-01

492

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

NASA Astrophysics Data System (ADS)

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 a 5056 resonator in which there were no explosive bonds. Numerical estimates of the quality factor of the bond material are obtained. From high-resolution resonant frequency measurements, the superconducting transition temperatures were determined and the effect of superconductivity on the torsion modulus was observed. The work was motivated by recent proposals to fabricate massive spherical resonant gravitational wave detectors from explosively bonded stacks of aluminium alloy plates.

Duffy, W.; Dalal, S.

493

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

494

Effects of process parameters on surface roughness in abrasive waterjet cutting of aluminium  

NASA Astrophysics Data System (ADS)

Abrasive waterjet cutting is a novel machining process capable of processing wide range of hard-to-cut materials. Surface roughness of machined parts is one of the major machining characteristics that play an important role in determining the quality of engineering components. This paper shows the influence of process parameters on surface roughness ( R a) which is an important cutting performance measure in abrasive waterjet cutting of aluminium. Taguchi's design of experiments was carried out in order to collect surface roughness values. Experiments were conducted in varying water pressure, nozzle traverse speed, abrasive mass flow rate and standoff distance for cutting aluminium using abrasive waterjet cutting process. The effects of these parameters on surface roughness have been studied based on the experimental results.

Chithirai Pon Selvan, M.; Mohana Sundara Raju, N.; Sachidananda, H. K.

2012-12-01

495

The formation of controlled-porosity membranes from anodically oxidized aluminium  

NASA Astrophysics Data System (ADS)

Synthetic membranes are used in a number of diverse applications, such as filtration1,2, bioreactors2,3, tissue culture4, analytical devices including sensors2,5, and as supports for active materials1,5. Narrow pore-size distribution, high pore density and thinness are often important attributes. The anodic oxidation of aluminium6 can produce porous films possessing these features; the anodizing voltage controls the pore size and pore density, whereas the thick-ness is determined by the amount of charge transferred. A major problem with this technique, however, is that the films remain attached to the aluminium, with the pore base closed by an oxide barrier layer. Here we overcome this problem by progressively reducing the anodizing voltage, thereby causing perforation of the barrier layer and separation of the film as a porous membrane.

Furneaux, R. C.; Rigby, W. R.; Davidson, A. P.

1989-01-01

496

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

497

Finite Element Analysis of Warpage in Laminated Aluminium Alloy Plates for Machining of Primary Aeronautic Parts  

SciTech Connect

The aim of this paper consists in presenting a method of simulating the warpage in 7xxx series aluminium alloy plates. To perform this simulation finite element software MSC.Patran and MSC.Marc were used. Another result of this analysis will be the influence on material residual stresses induced on the raw material during the rolling process upon the warpage of primary aeronautic parts, fabricated through machining (milling) at Embraer. The method used to determinate the aluminium plate residual stress was Layer Removal Test. The numerical algorithm Modified Flavenot Method was used to convert layer removal and beam deflection in stress level. With such information about the level and profile of residual stresses become possible, during the step that anticipate the manufacturing to incorporate these values in the finite-element approach for modelling warpage parts. Based on that warpage parameter surely the products are manufactured with low relative vulnerability propitiating competitiveness and price.

Reis, A. C.; Moreira Filho, L. A. [ITA - Aeronautic Technological Institute, IEM, Praca Mal. Eduardo Gomes, 50 - Vila das Acacias - S. J. Campos, CEP 1228-900 (Brazil); Menezes, M. A. [ITA - Aeronautic Technological Institute, IEM, Praca Mal. Eduardo Gomes, 50 - Vila das Acacias - S. J. Campos, CEP 1228-900 (Brazil); UNESP - Sao Paulo State University, Ilha Solteira Engineering Faculty, DEM, Av. Brasil, 56 - Centro - Ilha Solteira - SP, CEP 15385-000 (Brazil)

2007-04-07

498

Finite Element Analysis of Warpage in Laminated Aluminium Alloy Plates for Machining of Primary Aeronautic Parts  

NASA Astrophysics Data System (ADS)

The aim of this paper consists in presenting a method of simulating the warpage in 7xxx series aluminium alloy plates. To perform this simulation finite element software MSC.Patran and MSC.Marc were used. Another result of this analysis will be the influence on material residual stresses induced on the raw material during the rolling process upon the warpage of primary aeronautic parts, fabricated through machining (milling) at Embraer. The method used to determinate the aluminium plate residual stress was Layer Removal Test. The numerical algorithm Modified Flavenot Method was used to convert layer removal and beam deflection in stress level. With such information about the level and profile of residual stresses become possible, during the step that anticipate the manufacturing to incorporate these values in the finite-element approach for modelling warpage parts. Based on that warpage parameter surely the products are manufactured with low relative vulnerability propitiating competitiveness and price.

Reis, A. C.; Menezes, M. A.; Moreira Filho, L. A.

2007-04-01

499

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

NASA Astrophysics Data System (ADS)

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; Hao, Xiaojing; Ho-Baillie, Anita; Green, Martin A.

2014-02-01

500

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