2,2',3,4-Tetrahydroxy-3'-sulpho-5'-nitroazobenzene for spectrophotometric determination of aluminium in pharmaceutical suspensions and granite

International Nuclear Information System (INIS)

Guray, Tufan; Uysal, Uelkue Dilek; Gedikbey, Tevfik; Huseyinli, A. Ali

2005-01-01

A selective and sensitive new spectrophotometric method has been developed for the determination of aluminium. 2,2',3,4-Tetrahydroxy-3'-sulpho-5'-nitroazobenzene (tetrahydroxyazon SN) formed an orange chelate with aluminium at pH 4. Molar absorptivity of the complex in 1:2 is 5.46 x 10 4 l mol -1 cm -1 at 479 nm. The method obeys Beer's law in the range of 0.005-1.079 μg ml -1 . The determination of aluminium is not interfered with by earth alkaline, alkaline elements, rare earth elements, halides, phosphates, sulphates, urea, ascorbic acid, Sn 2+ , Sr 2+ , Cr 3+ , Cd 2+ , Hg 2+ , or Mn 2+ . The proposed method is rapid and simple, and it has been successfully applied to the determination of aluminium in certified pharmaceutical suspension and granite

Removal of sulphates from waste waters by sulphate-reducing bacteria

Directory of Open Access Journals (Sweden)

Luptáková Alena

2002-03-01

Full Text Available are present in almost all types of water, usually as a simple anion SO42-. The sulphates together with hydrogencarbonates and chlorides are principal anions in natural waters. In typical underground and surface waters, the concentration of sulphates is in the range from ten to hundreds milligrams per litre.Nowadays, the importance of the control of sulphate concentration in waste waters increases. According to the Slovak legislation the limit concentration of sulphates in surface and drinking waters is 250 mg.l-1 . In rivers the contents of sulphates increases mainly by the discharge of waste waters, which are coming mainly from chemical, textile, metallurgical, pharmaceutical, paper and mining industry. The concentration of sulphates in these waters is in the order of grams per litre.Many technologies for the sulphates removal from waste waters exist, including biologico-chemical processes. The principle of one of these methods is the reduction of sulphates by sulphate-reducing bacteria to hydrogen-sulphide.The objective of this work was to study the effect of initial sulphates concentration on the activity of anaerobic sulphate reducers as well as the kinetics of the anaerobic sulphate reduction. The batch reactor was used at temperature of 30°C and pH 7,5. Lactate was used as the carbon source.

Stimulation of amphibian gastroduodenal bicarbonate secretion by sucralfate and aluminium: role of local prostaglandin metabolism.

Science.gov (United States)

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

1988-01-01

The present studies were designed to explore the possible mode of protective and ulcer healing actions of sucralfate by examining its effect on gastroduodenal bicarbonate secretion by isolated amphibian mucosa. Luminal sucralfate (0.5 g/l) significantly increased bicarbonate secretion by fundic and antral mucosa without influencing transmucosal potential difference. Significant stimulation of duodenal bicarbonate secretion occurred only at 1.0 g/l without change in potential difference. Aluminium, a component of sucralfate, produced similar increases in bicarbonate secretion, while the sucrose and sulphate components were without effect. Pretreatment of mucosae with the cyclooxygenase inhibitor, indomethacin (10 5M) did not abolish the secretory response to sucralfate or aluminium. The results suggest that stimulation of gastroduodenal bicarbonate secretion, possibly by the aluminium moiety of sucralfate, may play a role in its protective and ulcer healing actions. PMID:3260886

Sulphate in Pregnancy

Directory of Open Access Journals (Sweden)

Paul A. Dawson

2015-03-01

Full Text Available Sulphate is an obligate nutrient for healthy growth and development. Sulphate conjugation (sulphonation of proteoglycans maintains the structure and function of tissues. Sulphonation also regulates the bioactivity of steroids, thyroid hormone, bile acids, catecholamines and cholecystokinin, and detoxifies certain xenobiotics and pharmacological drugs. In adults and children, sulphate is obtained from the diet and from the intracellular metabolism of sulphur-containing amino acids. Dietary sulphate intake can vary greatly and is dependent on the type of food consumed and source of drinking water. Once ingested, sulphate is absorbed into circulation where its level is maintained at approximately 300 μmol/L, making sulphate the fourth most abundant anion in plasma. In pregnant women, circulating sulphate concentrations increase by twofold with levels peaking in late gestation. This increased sulphataemia, which is mediated by up-regulation of sulphate reabsorption in the maternal kidneys, provides a reservoir of sulphate to meet the gestational needs of the developing foetus. The foetus has negligible capacity to generate sulphate and thereby, is completely reliant on sulphate supply from the maternal circulation. Maternal hyposulphataemia leads to foetal sulphate deficiency and late gestational foetal death in mice. In humans, reduced sulphonation capacity has been linked to skeletal dysplasias, ranging from the mildest form, multiple epiphyseal dysplasia, to achondrogenesis Type IB, which results in severe skeletal underdevelopment and death in utero or shortly after birth. Despite being essential for numerous cellular and metabolic functions, the nutrient sulphate is largely unappreciated in clinical settings. This article will review the physiological roles and regulation of sulphate during pregnancy, with a particular focus on animal models of disturbed sulphate homeostasis and links to human pathophysiology.

Aluminum sulphate production and zeolite from residual muds of the company Extralum S.A

International Nuclear Information System (INIS)

Carranza, C.; Montero, M.

2002-01-01

As part of our research on alternative raw materials for the chemical industry we studied sludge from an anodizing process at Extralum S.A. The sludge contains mainly bayerite, Al(OH) 3 and bohemite A1O (OH). Starting from these we developed a hydrothermal synthesis of Aluminium sulphate and Zeolite A. The Zeolite A was identified by Powder X-ray crystallography. The scanning electron microscope image of the Zeolite A shows a very high degree of crystallinity. (Author) [es

Effect of Poly Aluminium Chloride (PAC) on some blood constituents of Nile Tilapia (Oreochromis niloticus)

International Nuclear Information System (INIS)

Adam, H. M.; Agab, H.

2006-01-01

Poly aluminium chloride (PAC) is an urban drinking water purification substance that was introduced recently in Sudan and used to substitute polymer poly diallyl dimethyl aluminium chloride (DADMAC) and aluminium sulphate in water purification treatments. This study was conducted to determine its effects on fish health, which is is considered a biological indicator and an essential component of fresh water ecosystem. In this experiment, PAC was used in three different concentrations (0.1, 0.2 and 0.3 ml/1) in experimental tanks to achieve the desirable doses for the study. The tanks were populated by Nile Tilapia fingerlings (Oreochromis niloticus) with an average weight ranging between 70 and 100 grams. Exposure of this fish to PAC resulted in an immediate signification reduction (P<0.01) in haemoglobin concentration, erythrocytes count, packed cell volume, mean corpuscular volume and mean corpuscular haemoglobin concentration of experimental fingerlings blood. The degree of reduction in these parameters was directly proportional to the concentration of PAC used. (Author)

Study on the influence of Sempervivum tectorum and Melatonin on Glutathion protective effects in rats blood exposed to Aluminum sulphate

Directory of Open Access Journals (Sweden)

Corina Gravila

2014-05-01

Full Text Available The present study was carried out to investigate the influence of Sempervivum tectorum aqueous extract and melatonin on reduced glutathione (GSH protective effect in Wistar albino rat blood exposed to aluminium sulphate- Al2(SO43. The rats were divided in one control group (C and 7 experimental groups (E. The control group received tap water. The experimental rats were feed the following way: E1 group – aluminum sulphate, daily, for 3 months; : E2 group – Sempervivum tectorum, daily, for 3 months; : E3 group – melatonin, daily, for 3 months; : E4 group – aluminum sulphate with Sempervivum tectorum, daily, for 3 months; : E5 group – aluminum sulphate with melatonin, daily, for 3 months; E6 group – aluminum sulphate, daily, for 3 months, and thereafter with Sempervivum tectorum for 1 month; E7 group – aluminum sulphate, daily, for 3 month, and thereafter with melatonin for 1 month. This study showed that Aluminum toxicity induced lower GSH. The oxidative stress caused by aluminum, given individual, is more pronounced than in the case in which aluminum is administered simultaneously with Sempervivum tectorum or melatonin. Decreasing GSH value is very small if Sempervivum tectorum or melatonin is given for one month, three months after the administration of aluminum. Effect induced by melatonin is more favorable than that of Sempervivum tectorum.

Aluminium production

International Nuclear Information System (INIS)

Winter, B.; Ayers, J.; Sammer, G.

2001-01-01

Aluminium is the most important non-ferrous metal by quantity. Aluminium is produced by electrolysis of aluminium oxide (also known as alumina). Alumina is produced by refining bauxite. The quantity of primary and secondary aluminium production in ECE-countries between 1992 and 1998 is shown. The European aluminium industry employs approximately 200 000 employees. The annual aluminium production in the European Union was 3.58 million tonnes in 1994, of which 44 % was secondary aluminium. In 1996 3.96 million tonnes of aluminium were produced in the EU, of which 44 % was secondary aluminium. (author)

Incorporation of layered double nanomaterials in thin film nanocomposite nanofiltration membrane for magnesium sulphate removal

Science.gov (United States)

Hanis Tajuddin, Muhammad; Yusof, Norhaniza; Salleh, Wan Norharyati Wan; Fauzi Ismail, Ahmad; Hanis Hayati Hairom, Nur; Misdan, Nurasyikin

2018-03-01

Thin film nanocomposite (TFN) membrane with copper-aluminium layered double hydroxides (LDH) incorporated into polyamide (PA) selective layer has been prepared for magnesium sulphate salt removal. 0, 0.05, 0.1, 0.15, 0.2 wt% of LDH were dispersed in the trimesoyl chloride (TMC) in n-hexane as organic solution and embedded into PA layer during interfacial polymerization with piperazine. The fabricated membranes were further characterized to evaluate its morphological structure and membrane surface hydrophilicity. The TFN membranes performance were evaluated with divalent salt magnesium sulphate (MgSO4) removal and compared with thin film composite (TFC). The morphological structures of TFN membranes were altered and the surface hydrophilicity were enhanced with addition of LDH. Incorporation of LDH has improved the permeate water flux by 82.5% compared to that of TFC membrane with satisfactory rejection of MgSO4. This study has experimentally validated the potential of LDH to improve the divalent salt separation performance for TFN membranes.

Incorporation of layered double nanomaterials in thin film nanocomposite nanofiltration membrane for magnesium sulphate removal

Directory of Open Access Journals (Sweden)

Tajuddin Muhammad Hanis

2018-01-01

Full Text Available Thin film nanocomposite (TFN membrane with copper-aluminium layered double hydroxides (LDH incorporated into polyamide (PA selective layer has been prepared for magnesium sulphate salt removal. 0, 0.05, 0.1, 0.15, 0.2 wt% of LDH were dispersed in the trimesoyl chloride (TMC in n-hexane as organic solution and embedded into PA layer during interfacial polymerization with piperazine. The fabricated membranes were further characterized to evaluate its morphological structure and membrane surface hydrophilicity. The TFN membranes performance were evaluated with divalent salt magnesium sulphate (MgSO4 removal and compared with thin film composite (TFC. The morphological structures of TFN membranes were altered and the surface hydrophilicity were enhanced with addition of LDH. Incorporation of LDH has improved the permeate water flux by 82.5% compared to that of TFC membrane with satisfactory rejection of MgSO4. This study has experimentally validated the potential of LDH to improve the divalent salt separation performance for TFN membranes.

Cancer risk among workers of a secondary aluminium smelter.

Science.gov (United States)

Maltseva, A; Serra, C; Kogevinas, M

2016-07-01

Cancer risk in secondary aluminium production is not well described. Workers in this industry are exposed to potentially carcinogenic agents from secondary smelters that reprocess aluminium scrap. To evaluate cancer risk in workers in a secondary aluminium plant in Spain. Retrospective cohort study of male workers employed at an aluminium secondary smelter (1960-92). Exposure histories and vital status through 2011 were obtained through personal interviews and hospital records, respectively. Standardized mortality (SMRs) and incidence ratios (SIRs) were calculated. The study group consisted of 98 workers. We found increased incidence and mortality from bladder cancer [SIR = 2.85, 95% confidence interval (CI) 1.23-5.62; SMR = 5.90, 95% CI 1.58-15.11]. Increased incidence was also observed for prostate cancer and all other cancers but neither were statistically significant. No increased risk was observed for lung cancer. Results of this study suggest that work at secondary aluminium smelters is associated with bladder cancer risk. Identification of occupational carcinogens in this industry is needed. © The Author 2016. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The Reclamation of Industrial Wastes Inclusive Sulphates by Sulphate-Reducing Bacteria

Directory of Open Access Journals (Sweden)

Mária Kušnierová

2004-12-01

Full Text Available The objective of our study was to verify experimentally the possibility of using coal mine drainage and gypsum from the „stabilizate“ (the final product from the combustion desulphurisation as the source of sulphate for the cultivation of SRB with the prospect of: purging of mine waste waters inclusive sulphates, recycling of desulphurisation agent (limestone and production of elemental sulphur from hydrogen sulphide. The results confirmed the theoretical assumptions on the use of gypsum, which forms the substantial component of „stabilizate“, as the source of sulphate for sulphate-reducing bacteria, which produce hydrogen sulphide in the process of bacterial reduction of sulphates. They also showed the possibility of recycling the desulphurisation agent – limestone, as well as the realistic alternative of using „stabilizate“ in the production of elemental sulphur which still represents an important raw material needed in chemical, paper or other industries.

Pengaruh Kuat Arus Listrik Dan Waktu Proses Anodizing Dekoratif Pada Aluminium Terhadap Kecerahan Dan Ketebalan Lapisan

OpenAIRE

I Gst. Ngr. Nitya Santhiarsa

2012-01-01

To increase assess aluminium of decorative aspect hence finishing processes must be used, like coloringprocess. Hence layer anodizing developed now where you can make aluminum metal look more interesting so thefinish can increase the economic value. Anodizing is the process formation of oxide layer on the metal with themetal, especially aluminum reacting with oxygen (O2) from the electrolyte sulphate acid (H2SO4).This research uses2024-T3 aluminum metal as a parent to be coated, with the elec...

Aluminium bridges, aluminium bridge decks

NARCIS (Netherlands)

Soetens, F.; Straalen, IJ.J. van

2003-01-01

Applications of aluminium have grown considerably in building and civil engineering the last decade. In building and civil engineering the increase of aluminium applications is due to various aspects like light weight, durability and maintenance, use of extrusions, and esthetics. The paper starts

Zinc Improves Cognitive and Neuronal Dysfunction During Aluminium-Induced Neurodegeneration.

Science.gov (United States)

Singla, Neha; Dhawan, D K

2017-01-01

Metals are considered as important components of a physiologically active cell, and imbalance in their levels can lead to various diseased conditions. Aluminium (Al) is an environmental neurotoxicant, which is etiologically related to several neurodegenerative disorders like Alzheimer's, whereas zinc (Zn) is an essential trace element that regulates a large number of metabolic processes in the brain. The objective of the present study was to understand whether Zn provides any physiological protection during Al-induced neurodegeneration. Male Sprague Dawley rats weighing 140-160 g received either aluminium chloride (AlCl 3 ) orally (100 mg/kg b.wt./day), zinc sulphate (ZnSO 4 ) in drinking water (227 mg/L) or combined treatment of aluminium and zinc for 8 weeks. Al treatment resulted in a significant decline in the cognitive behaviour of rats, whereas zinc supplementation caused an improvement in various neurobehavior parameters. Further, Al exposure decreased (p ≤ 0.001) the levels of neurotransmitters, acetylcholinesterase activity, but increased (p ≤ 0.001) the levels of L-citrulline as well as activities of nitric oxide and monoamine oxidase in the brain. However, zinc administration to Al-treated animals increased the levels of neurotransmitters and regulated the altered activities of brain markers. Western blot of tau, amyloid precursor protein (APP), glial fibrillary acidic protein (GFAP), ubiquitin, α-synuclein and Hsp 70 were also found to be elevated after Al exposure, which however were reversed following Zn treatment. Al treatment also revealed alterations in neurohistoarchitecture in the form of loss of pyramidal and Purkinje cells, which were improved upon zinc co-administration. Therefore, the present study demonstrates that zinc improves cognitive functions by regulating α-synuclein and APP-mediated molecular pathways during aluminium-induced neurodegeneration.

Alloys of uranium and aluminium with low aluminium content; Alliages uranium-aluminium a faible teneur en aluminium

Energy Technology Data Exchange (ETDEWEB)

Cabane, G; Englander, M; Lehmann, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1955-07-01

Uranium, as obtained after spinning in phase {gamma}, presents an heterogeneous structure with large size grains. The anisotropic structure of the metal leads to an important buckling and surface distortion of the fuel slug which is incompatible with its tubular cladding for nuclear fuel uses. Different treatments have been made to obtain an isotropic structure presenting high thermal stability (laminating, hammering and spinning in phase {alpha}) without success. Alloys of uranium and aluminium with low aluminium content present important advantage in respect of non allied uranium. The introduction of aluminium in the form of intermetallic compound (UAl{sub 2}) gives a better resistance to thermal fatigue. Alloys obtained from raw casting present an improved buckling and surface distortion in respect of pure uranium. This improvement is obtained with uranium containing between 0,15 and 0,5 % of aluminium. An even more improvement in thermal stability is obtained by thermal treatments of these alloys. These new characteristics are explained by the fine dispersion of the UAl{sub 2} particles in uranium. The results after treatments obtained from an alloy slug containing 0,4 % of aluminium show no buckling or surface distortion and no elongation. (M.P.)

Rows of Dislocation Loops in Aluminium Irradiated by Aluminium Ions

DEFF Research Database (Denmark)

Henriksen, L.; Johansen, A.; Koch, J.

1967-01-01

Single-crystal aluminium specimens, irradiated with 50-keV aluminium ions, contain dislocation loops that are arranged in regular rows along <110 > directions. ©1967 The American Institute of Physics......Single-crystal aluminium specimens, irradiated with 50-keV aluminium ions, contain dislocation loops that are arranged in regular rows along directions. ©1967 The American Institute of Physics...

Electrochemical study in the molten sodium acid sulphate - potassium acid sulphate eutectic

International Nuclear Information System (INIS)

Le Ber, F.

1964-01-01

The general properties of the NaHSO 4 - KHSO 4 molten eutectic resemble those of neutral sulphates and those of concentrated H 2 SO 4 . We have been able to show the existence in solution of the ions HSO - 4 SO 2- 4 , and H 3 O + , these last being formed by the action of the HSO - 4 ions on dissolved H 2 O. The electro-active zone with a polished platinum electrode is limited in oxidation by the ions H 3 O + and SO 2- 4 , and in reduction by the protons of HSO - 4 . We have compared the electro-active zones obtained with different electrodes (Ag-Au-graphite-mercury). We have considered the dissolution of a few metallic oxides and halides. This work shows the role as O 2- ion acceptors of HSO - 4 ions. We have undertaken an electro-chemical study of a few oxido-reduction Systems: H + / H 2 , Ag↓ / Ag (1), the vanadium and uranium Systems, those of mercury Hg↓ / Hg 2- 2 and of gold Au/Au 3+ , then of the attack by the solvent of a few common metals such as aluminium, iron, copper and nickel. The study of silver Systems has made it possible to obtain the solubility products of AgCl and AgBr and to consider the possibility of coulometric titration Cl - ions with Ag + ions. We have shown the existence of various chemical species of vanadium which may exist in the molten eutectic. (author) [fr

Investigation of aluminium-rich alloy system of aluminium-strontium-silicium

International Nuclear Information System (INIS)

Ganiev, I.N.; Vakhobov, A.B.; Dzhuraev, T.D.; Alidzhanov, F.N.

1976-01-01

An area of the solid solution based on aluminium was studied, and the surface was plotted of the liquidus adjoining the apex of the aluminium corner of the strontium-aluminium-silicon system. The investigation was carried out by microstructure and differential thermal analyses and by the measurement of the microhardness of the component phases. A combined solubility of silicon and strontium in aluminium was studied along three radial sections at Sr-to-Si ratios of 1/2, 1/1 and 2/1. The relationships of ''composition vs. Microhardness'', obtained in these sections, made it possible to define the boundaries of the phase regions in the aluminium corner of the strontium-aluminium-silicon system at 500 deg C. The greatest solubility is that along the Al-SrAl 2 Si 2 section at a Sr/Si ratio of 1/2. A further increase in the content of strontium brings about a drop in the solubility of silicon in solid aluminium. The projection of the liquidus surface of the strontium-aluminium-silicon system, rich in aluminium, includes four surfaces of primary crystallization: α-Al, SrAl 4 , SrAl 2 Si 2 and Si. The system comprises a section of Al-SrAl 2 Si 2 representing a quasibinary system of an eutectic type. The eutectic reaction takes place at a temperature of 640 deg C. The quasibinary Al-SrAl 2 Si 2 section divides the aluminium corner of the Sr-Al-Si system into two independent systems Al-SrAl 4 -SrAl 2 Si 2 and Al-Si-SrAl 2 Si 2 of an eutectic type

Thermodynamic analysis of dust sulphation reactions

Energy Technology Data Exchange (ETDEWEB)

Yang Yongxiang; Jokilaakso, A.

1997-12-31

Sulphation reactions of metal oxides with SO{sub 2} and O. or SO{sub 3} play significant roles in sulphation roasting of sulphide and oxide minerals as well as in desulphurisation process of combustion gases. In metallurgical waste-heat boilers for sulphide smelting, the sulphation of the oxidic flue dust in the atmosphere containing sulphur oxides is an unavoidable process, and the sulphation reactions have to be guided in a controlled way in the proper parts of the gas handling equipment. In this report, some thermodynamic analyses were conducted for the oxide sulphation reactions in relation to sulphide smelting processes. The phase stability of Me-S-O systems especially for oxides - sulphates equilibrium was studied under different thermodynamic conditions of gas compositions and temperatures. The sulphate stability was analysed for an example of gas compositions in the copper flash smelter of Outokumpu Harjavalta Metals Oy, in relation to temperature. In the report, most of the information was from literature. Moreover, a number of thermodynamic computations were carried out with the HSC program, and the constructed phase stability diagrams were compared with those from the literature whenever possible. The maximum temperatures for stable sulphates under normal operating conditions of the waste-heat boilers in sulphide smelting processes were obtained. This report will serve as the basis for the kinetic studies of the sulphation reactions and the sulphation reaction modelling in pyrometallurgical processes. (orig.) SULA 2 Programme. 36 refs.

Aluminium in human sweat.

Science.gov (United States)

Minshall, Clare; Nadal, Jodie; Exley, Christopher

2014-01-01

It is of burgeoning importance that the human body burden of aluminium is understood and is measured. There are surprisingly few data to describe human excretion of systemic aluminium and almost no reliable data which relate to aluminium in sweat. We have measured the aluminium content of sweat in 20 healthy volunteers following mild exercise. The concentration of aluminium ranged from 329 to 5329μg/L. These data equate to a daily excretion of between 234 and 7192μg aluminium and they strongly suggest that perspiration is the major route of excretion of systemic aluminium in humans. Copyright © 2013 Elsevier GmbH. All rights reserved.

Sulphate removal from sodium sulphate-rich brine and recovery of barium as a barium salt mixture.

Science.gov (United States)

Vadapalli, Viswanath R K; Zvimba, John N; Mulopo, Jean; Motaung, Solly

2013-01-01

Sulphate removal from sodium sulphate-rich brine using barium hydroxide and recovery of the barium salts has been investigated. The sodium sulphate-rich brine treated with different dosages of barium hydroxide to precipitate barium sulphate showed sulphate removal from 13.5 g/L to less than 400 mg/L over 60 min using a barium to sulphate molar ratio of 1.1. The thermal conversion of precipitated barium sulphate to barium sulphide achieved a conversion yield of 85% using coal as both a reducing agent and an energy source. The recovery of a pure mixture of barium salts from barium sulphide, which involved dissolution of barium sulphide and reaction with ammonium hydroxide resulted in recovery of a mixture of barium carbonate (62%) and barium hydroxide (38%), which is a critical input raw material for barium salts based acid mine drainage (AMD) desalination technologies. Under alkaline conditions of this barium salt mixture recovery process, ammonia gas is given off, while hydrogen sulfide is retained in solution as bisulfide species, and this provides basis for ammonium hydroxide separation and recovery for reuse, with hydrogen sulfide also recoverable for further industrial applications such as sulfur production by subsequent stripping.

Sulphate reduction in the Aespoe HRL tunnel

International Nuclear Information System (INIS)

Gustafson, G.; Pedersen, K.; Tullborg, E.L.; Wallin, B.; Wikberg, P.

1995-12-01

Evidence and indications of sulphate reduction based on geological, hydrogeological, groundwater, isotope and microbial data gathered in and around the Aespoe Hard Rock Laboratory tunnel have been evaluated. This integrated investigation showed that sulphate reduction had taken place in the past but is most likely also an ongoing process. Anaerobic sulphate-reducing bacteria can live in marine sediments, in the tunnel sections under the sea and in deep groundwaters, since there is no access to oxygen. The sulphate-reducing bacteria seem to thrive when the Cl - concentration of the groundwater is 4000-6000 mg/l. Sulphate reduction is an in situ process but the resulting hydrogen-sulphide rich water can be transported to other locations. A more vigorous sulphate reduction takes place when the organic content in the groundwater is high (>10 mg/l DOC) which is the case in the sediments and in the groundwaters under the sea. Some bacteria use hydrogen as an electron donor instead of organic carbon and can therefore live in deep environments where access to organic material is limited. The sulphate-reducing bacteria seem to adapt to changing flow situations caused by the tunnel construction relatively fast. Sulphate reduction seems to have occurred and will probably occur where conditions are favourable for the sulphate-reducing bacteria such as anaerobic brackish groundwater with dissolved sulphate and organic carbon or hydrogen. 59 refs, 37 figs, 6 tabs

Human exposure to aluminium.

Science.gov (United States)

Exley, Christopher

2013-10-01

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

Determination of Aluminium Content in Aluminium Hydroxide Formulation by FT-NIR Transmittance Spectroscopy

DEFF Research Database (Denmark)

Lai, Xuxin; Zheng, Yiwu; Søndergaard, Ib

2007-01-01

A method for determining the aluminium content of an aluminium hydroxide suspension using near infrared (NIR) transmittance spectroscopy has been developed. Inductively coupled plasma-atomic emission spectroscopy (ICP-AES) was used as reference method. The factors influencing the NIR analysis...... aluminium content in aluminium hydroxide suspension. (c) 2007 Elsevier Ltd. All rights reserved....

Copper sulphate poisoning in horses

Energy Technology Data Exchange (ETDEWEB)

Bauer, M

1975-01-01

In the archives of the Clinic for Internal Diseases of Domestic Animals at the Veterinary Faculty of Zagreb University some thirty cases of horse disease diagnosed as copper sulphate poisoning were noted. The data correspond in many respects to the clinical findings of copper sulphate poisoning in other domestic animals. A series of experimental horse poisonings were undertaken in order to determine the toxicity of copper sulphate. The research results are as follows: Horses are sensitive to copper sulphate. Even a single application of 0.125 g/kg body weight in 1% concentration by means of incubation into the stomach causes stomach and gut disturbances and other poisoning symptoms. Poisoning occurs in two types: acute and chronic. The former appears after one to three applications of copper sulphate solution and is characterized by gastroenteritis, haemolysis, jaundice and haemoglobinuria with signs of consecutive damage of kidney, liver and other organs. The disease, from the first application to death lasts for two weeks. Chronic poisoning is caused by ingestion of dry copper sulphate in food (1% solution dried on hay or clover) for two or more months. There are chronic disturbances of stomach and gut and loss of weight, and consecutive (three to four) haemolytic crises similar to those of acute poisoning. From the beginning of poisoning to death six or more months can elapse.

Effect of Bio char on Plant Growth and Aluminium Form of Soil under Aluminium Stress

Science.gov (United States)

Qian, Lianwen; Li, Qingbiao; Sun, Jingwei; Feng, Ying

2018-01-01

Aluminium-enriched acid red soils in South China easily cause aluminium toxicity to plants, but biochip can improve soils and eliminate soil contaminations. In this project, biochip was used in potted plant control test to study the effect of biochip on plant growth in soil under acid aluminium stress and the migration and conversion of aluminium in plant-soil system. The fin dings show that the application of biochip increases the pH value of soil under aluminium stress significantly, changes the existing form of aluminium ion in soil, reduces the plants’ absorption of aluminium, and alleviates the aluminium toxicity to plants, but too much biochip may inhibit the growth of plants. In this case, further study should be carried out as regards the volume and way of biochip input in practical applications as well as the timeliness of aluminium toxicity removal.

Confined recrystallization of high-purity aluminium during accumulative roll bonding of aluminium laminates

International Nuclear Information System (INIS)

Chekhonin, Paul; Beausir, Benoît; Scharnweber, Juliane; Oertel, Carl-Georg; Hausöl, Tina; Höppel, Heinz Werner; Brokmeier, Heinz-Günter; Skrotzki, Werner

2012-01-01

Aluminium laminates consisting of high-purity aluminium and commercially pure aluminium have been produced by accumulative roll bonding (ARB) at ambient temperature for up to 10 cycles. To study the microstructure and texture development of the high-purity aluminium layers with regard to the shrinking layer thickness during ARB, microstructure and texture investigations were carried out by electron backscatter diffraction and neutron and X-ray diffraction, respectively. While the commercially pure aluminium layers develop an ultrafine-grained microstructure, partial discontinuous recrystallization occurs in the high-purity layers. The texture of the high-purity layers mainly consists of Cube and “Tilted Cube” (tilted with respect to the transverse direction) components. The experimental results are discussed with respect to confined recrystallization in the ARB aluminium laminates.

Alloys of uranium and aluminium with low aluminium content

International Nuclear Information System (INIS)

Cabane, G.; Englander, M.; Lehmann, J.

1955-01-01

Uranium, as obtained after spinning in phase γ, presents an heterogeneous structure with large size grains. The anisotropic structure of the metal leads to an important buckling and surface distortion of the fuel slug which is incompatible with its tubular cladding for nuclear fuel uses. Different treatments have been made to obtain an isotropic structure presenting high thermal stability (laminating, hammering and spinning in phase α) without success. Alloys of uranium and aluminium with low aluminium content present important advantage in respect of non allied uranium. The introduction of aluminium in the form of intermetallic compound (UAl 2 ) gives a better resistance to thermal fatigue. Alloys obtained from raw casting present an improved buckling and surface distortion in respect of pure uranium. This improvement is obtained with uranium containing between 0,15 and 0,5 % of aluminium. An even more improvement in thermal stability is obtained by thermal treatments of these alloys. These new characteristics are explained by the fine dispersion of the UAl 2 particles in uranium. The results after treatments obtained from an alloy slug containing 0,4 % of aluminium show no buckling or surface distortion and no elongation. (M.P.)

Radioprotective effects of dextran sulphate in mice

International Nuclear Information System (INIS)

Vacek, A.; Bartonickova, A.; Rotkovska, D.; Palyga, G.F.; Zhukova, N.A.

1981-01-01

Influence of a single i.p. injection of dextran sulphate on radiosensitivity of mice was investigated. The administration of dextran sulphate 24, 48 and 72 hours prior to irradiation increased formation of endogenous colonies of the hemopoietic tissue on the surface of the spleen. DRF calculated from an equieffective exposure for 5 colonies was 1.96 when dextran sulphate was administered 24 hours before irradiation, and 2.25 when dextran sulphate was administered 72 hours before irradiation. The radioprotective effects of dextran sulphate were manifested also in the survival of animals exposed to lethal doses of short-termed as well as long-termed gamma radiation. (orig.) [de

Sulphate solubility and sulphate diffusion in oxide glasses: implications for the containment of sulphate-bearing nuclear wastes; Solubilite et cinetiques de diffusion des sulfates dans differents verres d'oxydes: application au conditionnement des dechets nucleaires sulfates

Energy Technology Data Exchange (ETDEWEB)

Lenoir, M.

2009-09-15

The thesis deals with sulphate solubility and sulphate diffusion in oxide glasses, in order to control sulphate incorporation and sulphate volatilization in nuclear waste glasses. It was conducted on simplified compositions, in the SiO{sub 2}-B{sub 2}O{sub 3}-R{sub 2}O (R = Li, Na, K, Cs), SiO{sub 2}-B{sub 2}O{sub 3}-BaO and V{sub 2}O{sub 5}-B{sub 2}O{sub 3}-BaO systems. These compositions allowed us to study the influence of the nature of network-modifying ions (Li{sup +}, Na{sup +}, K{sup +}, Cs{sup +} or Ba{sup 2+}) and also of former elements (Si, B, V), on structure and properties of glasses. Sulphate volatility is studied in sodium borosilicate melts using an innovative technique of sulphate quantitation with Raman spectroscopy. This technique is useful to obtain kinetic curves of sulphate volatilization. The establishment of a model to fit these curves leads to the determination of diffusion coefficients of sulphate. These diffusion coefficients can thus be compared to diffusion coefficients of other species, determined by other techniques and presented in the literature. They are also linked to diffusion coefficients in relation with the viscosity of the melts. Concerning sulphate solubility in glasses, it depends on glass composition and on the nature of sulphate incorporated. Sulphate incorporation in alkali borosilicate glasses leads to the formation of a sulphate layer floating on top of the melt. Sulphate incorporation in barium borosilicate and boro-vanadate glasses leads to the crystallization of sulphate species inside the vitreous matrix. Moreover, sulphate solubility is higher in these glasses than in alkali borosilicates. Finally, exchanges between cations present in glasses and cations present in the sulphate phase are also studied. (author)

Toxicity of aluminium on five aquatic invertebrates; Aluminiums toksisitet paa 5 akvatiske invertebrater

Energy Technology Data Exchange (ETDEWEB)

Moe, J [Oslo Univ. (Norway)

1996-01-01

The conference paper deals with the experiments done by investigating the effects from the toxicity of aluminium on aquatic invertebrates. The aim of the experiments was to compare the toxicity of unstable aluminium compounds with stable forms of aluminium. 8 refs., 2 figs., 2 tabs.

Effect of Sintering Temperature on the Properties of Aluminium-Aluminium Oxide Composite Materials

Directory of Open Access Journals (Sweden)

Dewan Muhammad Nuruzzaman

2016-12-01

Full Text Available In this study, aluminium-aluminium oxide (Al-Al2O3 metal matrix composites of different weight percentage reinforcements of aluminium oxide were processed at different sintering temperatures. In order to prepare these composite specimens, conventional powder metallurgy (PM method was used. Three types specimens of different compositions such as 95%Al+5%Al2O3, 90%Al+10%Al2O3 and 85%Al+15%Al2O3 were prepared under 20 Ton compaction load. Then, all the specimens were sintered in a furnace at two different temperatures 550oC and 580oC. In each sintering process, two different heating cycles were used. After the sintering process, it was observed that undistorted flat specimens were successfully prepared for all the compositions. The effects of sintering temperature and weight fraction of aluminium oxide particulates on the density, hardness and microstructure of Al-Al2O3 composites were observed. It was found that density and hardness of the composite specimens were significantly influenced by sintering temperature and percentage aluminium oxide reinforcement. Furthermore, optical microscopy revealed that almost uniform distribution of aluminium oxide reinforcement within the aluminium matrix was achieved.

Dispersion strengthening of aluminium-aluminium-oxide products

DEFF Research Database (Denmark)

Hansen, Niels

1970-01-01

The true stress-true strain curves at room temperature and at 400°C were determined for various types of aluminium-aluminium-oxide products containing from 0.2 to 4.7 weight per cent of aluminium oxide. The effect of particles on the initial flow stress and the flow stress for 0.2% offset at room...... temperature and at 400°C is in agreement with Orowan's theory. The increase in flow stress at room temperature for strain values below 3 per cent was related to the plastic strain by the equation σ-σoy=k1ε 1/2, where σoy is the initial flow stress and where k1 increases for increasing volume fraction...... and decreasing particle size of the dispersed particles. A general expression for k1 was derived for the relationship between the dislocation density and the strain in dispersion-strengthened products...

The prophylactic reduction of aluminium intake.

Science.gov (United States)

Lione, A

1983-02-01

The use of modern analytical methods has demonstrated that aluminium salts can be absorbed from the gut and concentrated in various human tissues, including bone, the parathyroids and brain. The neurotoxicity of aluminium has been extensively characterized in rabbits and cats, and high concentrations of aluminium have been detected in the brain tissue of patients with Alzheimer's disease. Various reports have suggested that high aluminium intakes may be harmful to some patients with bone disease or renal impairment. Fatal aluminium-induced neuropathies have been reported in patients on renal dialysis. Since there are no demonstrable consequences of aluminium deprivation, the prophylactic reduction of aluminium intake by many patients would appear prudent. In this report, the major sources of aluminium in foods and non-prescription drugs are summarized and alternative products are described. The most common foods that contain substantial amounts of aluminium-containing additives include some processed cheeses, baking powders, cake mixes, frozen doughs, pancake mixes, self-raising flours and pickled vegetables. The aluminium-containing non-prescription drugs include some antacids, buffered aspirins, antidiarrhoeal products, douches and haemorrhoidal medications. The advisability of recommending a low aluminium diet for geriatric patients is discussed in detail.

Removal heavy metals and sulphate from waste waters by sulphate-reducing bacteria

Directory of Open Access Journals (Sweden)

Kušnierová Mária

2000-09-01

Full Text Available This article is devoted to the process of bacterial sulphate reduction, which is used to removal of heavy metals and sulphate ions from waste waters.The life of animals and plants depends on the existence of microscopic organisms – microorganisms (MO, which play an important role in cycle changes of biogenic elements on the earth. The sulphur cycle in the nature is considered as one of the oldest and most significant biological systems (Fig. 1. The sulphate-reducing bacteria (SRB miss the assimilatory part of the cycle and produce sulphides. The microbial population of this dissimilatory part is called “sulfuretum”. The SRB can be found in anaerobic mud and sediments of freshwater, thermal or non-thermal sulphur springs, mining waters from sulphide deposits, oil deposits, sea and ocean beds, and in the gastrointestinal tract of man and animals. The SRB represent a group of chemoorganotrophic, strictly anaerobic and gramnegative bacteria, which exhibit a great morphological and physiological diversity. Despite of their considerable morphological variety, they have one property in common, which is the ability to utilise preferentially sulphates (occasionally sulphites, thiosulphates, tetrathionates as electron acceptors, which are reduced to sulphides, during anaerobic respiration. The electron donors in these processes are simple organic compounds as lactate, malate, etc.,(heterotrophically reduction or gaseous hydrogen (autotrophically reduction. SRB can produce a considerable amount of hydrogen sulphide, which reacts easily in aqueous solution with the cations of heavy metals, forming metal sulphides that have low solubility. The bacterial sulphate reduction can be used for the treatment of acid mine drainage waters, which is considered to be the major problem associated with mining activities.In order to remove heavy metals from waste waters, e.g., from galvanizing plants, mine waters (Smolnik, Šobov locality and metallurgic plants (works

Removal of Sulphate and Manganese on Synthetic Wastewater in Sulphate Reducing Bioreactor Using Indonesian Natural Zeolite

Directory of Open Access Journals (Sweden)

Endah Retnaningrum

2017-07-01

Full Text Available The present research was conducted to investigate sulphate and manganese removal from synthetic wastewater. The continuous laboratory scale of down-flow fluidized-bed reactor (DFBR using sulphate reducing bacteria (SRB consortium and Indonesian natural zeolite as a bacterial support material was designed. At 9 days operation, maximum sulphate and manganese removal was observed to be 23% and 15.4%, respectively. The pH values were also changed to neutral. The population of SRB increased which effect on the raising of their activity for removing sulphate and manganese. Using the scanning electronic microscopy (SEM, it was observed that natural zeolite possesses excellent physical characteristics as a bacterial support material in DFBR. The imaging SEM result of SRB consortium on zeolite surface clearly showed the developed SRB biofilm on that particle. Analysis result of EDX confirmed that manganese was precipitated as manganese–sulfides.

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

Science.gov (United States)

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

1972-01-01

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.

TEM investigation of aluminium containing precipitates in high aluminium doped silicon carbide

International Nuclear Information System (INIS)

Wong-Leung, J.; FitzGerald, J.D.

2002-01-01

Full text: Silicon carbide is a promising semiconductor material for applications in high temperature and high power devices. The successful growth of good quality epilayers in this material has enhanced its potential for device applications. As a novel semiconductor material, there is a need for studying its basic physical properties and the role of dopants in this material. In this study, silicon carbide epilayers were grown on 4H-SiC wafers of (0001) orientation with a miscut angle of 8 deg at a temperature of 1550 deg C. The epilayers contained regions of high aluminium doping well above the solubility of aluminium in silicon carbide. High temperature annealing of this material resulted in the precipitation of aluminium in the wafers. The samples were analysed by secondary ion mass spectrometry and transmission electron microscopy. Selected area diffraction studies show the presence of aluminium carbide and aluminium silicon carbide phases. Copyright (2002) Australian Society for Electron Microscopy Inc

Demonstration of immunogenic keratan sulphate in commercial chondroitin 6-sulphate from shark cartilage. Implications for ELISA assays

DEFF Research Database (Denmark)

Møller, H J; Møller-Pedersen, T; Damsgaard, T E

1995-01-01

The prototype monoclonal keratan sulphate (KS) antibody 5D4 that is widely used for detection of KS in tissues and biological fluids reacts strongly with commercial low grade shark cartilage chondroitin 6-sulphate. Characterization of the immunogenic material by chondroitinase ABC digestion, ELISA...... cartilage chondroitin 6-sulphate is an easy accessible source of immunogenic KS that can be used as a reference standard and as coating antigen in KS-ELISAs. The concentration of immunogenic KS in synovial fluid measured with an ELISA based solely on reagents of shark cartilage chondroitin 6-sulphate...... correlated well (r = 0.90) with the concentrations obtained with a traditional KS-ELISA that uses purified aggrecan as standard and coating antigen, and KS in both serum and synovial fluid could be measured with sufficient linearity....

Effectivness of dexametasone vs. Magnesium sulphate in postoperative analgesia: Dexametasone vs. Magnesium sulphate

Directory of Open Access Journals (Sweden)

Dautaj Brikena

2016-01-01

Full Text Available Introduction: Preoperative use of additive substances may be very helpful in perioperative acute pain management. Intravenous administration of dexametasone in preoperative period prevents postoperative nausea and vomiting but also provides better pain relief. It is also well known that magnesium sulphate (the NMDA receptor's antagonist by its central mechanism of action may be effective in postoperative pain control. Aim: The purpose of this study was to evaluate the effect of dexametasone and magnesium sulphate on postoperative pain management in patients undergoing abdominal surgery (open cholecystectomy. Methods: Seventy eight patients scheduled for elective surgery (open cholecystectomy were included in this study. This was the prospective cohort randomized placebo- controlled study. A total of 78 patients were randomized into three groups. Each group had twenty six patients. The group D, received dexametasone 0.1 mg/ kg iv 30 minutes before surgery. The group M received magnesium sulphate 3 mg/kg iv 30 minutes before surgery. The third group S was placebo group and patients in this group received saline in the same volume for each patient. For pain control after surgery all patients received tramadol 0.9-1.2 mg/kg and diklophenac 1.76 mg/kg. When necessary (VAS ≥ 7, morphine sulphate in dose 0.15 mg/kg was administred subcutaneously For treatment of emetic episodes metoclopramid 10 mg iv. was used. The patients were observed for intensity of pain measured VAS 0-10, pain relief and satisfaction with therapy, sedation, adverse events, emetic episodes and hemodynamic parameters. Results: There was no difference between groups regarding demographic data (age, gender, body weight, ASA score, comorbidity, duration of surgery and anesthesia and amount of fentanyl received during surgery. In group D 11.54% of patients received additional analgesia (morphine sulphate 0.15 mg/kg sc in the first 4 hours and 27% of patients in the first 24 hours

Analysis of aluminium in rat following administration of allergen immunotherapy using either aluminium or microcrystalline-tyrosine-based adjuvants.

Science.gov (United States)

McDougall, Stuart A; Heath, Matthew D; Kramer, Matthias F; Skinner, Murray A

2016-03-01

Investigation into the absorption, distribution and elimination of aluminium in rat after subcutaneous aluminium adjuvant formulation administration using ICP-MS is described. Assays were verified under the principles of a tiered approach. There was no evidence of systemic exposure of aluminium, in brain or in kidney. Extensive and persistent retention of aluminium at the dose site was observed for at least 180 days after administration. This is the first published work that has quantified aluminium adjuvant retention based on the quantity of aluminium delivered in a typical allergy immunotherapy course. The results indicate that the repeated administration of aluminium-containing adjuvants will likely contribute directly and significantly to an individual's body burden of aluminium.

TITANIUM CARBON ALUMINIUM : A NOVEL GRAIN REFINER FOR ALUMINIUM-LITHIUM ALLOYS

OpenAIRE

Birch , M.; Cowell , A.

1987-01-01

This work explores the possibility of achieving grain size control in aluminium-lithium alloys with the titanium carbon aluminium (TiCAl) master alloys invented at the Technical University of Berlin and developed by London and Scandinavian Metallurgical Co Ltd (LSM). Grain refining tests were conducted on a single batch of 8090 alloy using addition rates of 0.2wt% and 0.4wt% of TiCAl and 3/1 titanium boron aluminium (TiBAl). Other tests using 0.4wt% of binary TiAl gave poor results, showing t...

Demonstration of immunogenic keratan sulphate in commercial chondroitin 6-sulphate from shark cartilage. Implications for ELISA assays

DEFF Research Database (Denmark)

Møller, H J; Møller-Pedersen, T; Damsgaard, T E

1995-01-01

The prototype monoclonal keratan sulphate (KS) antibody 5D4 that is widely used for detection of KS in tissues and biological fluids reacts strongly with commercial low grade shark cartilage chondroitin 6-sulphate. Characterization of the immunogenic material by chondroitinase ABC digestion, ELISA...... inhibition studies, immunoblotting and HPLC analyses confirmed the presence of substantial amounts of KS, probably as a large proteoglycan (> 120 kDa). Commercial and heterogenic glycosaminoglycan preparations therefore must be used with great caution in immunological analyses. On the other hand the shark...... cartilage chondroitin 6-sulphate is an easy accessible source of immunogenic KS that can be used as a reference standard and as coating antigen in KS-ELISAs. The concentration of immunogenic KS in synovial fluid measured with an ELISA based solely on reagents of shark cartilage chondroitin 6-sulphate...

Extraction of sulphates by long chain amines

International Nuclear Information System (INIS)

Boirie, Ch.

1959-05-01

The extraction of sulphuric acid by long chain amines in organic solution has been studied with a view to determining the value of the stability constants of the amine sulphates and bi-sulphates formed. We have concentrated chiefly on uranium sulphate and thorium sulphate. The formulae of the complexes extractable with amines have been established, as well as the corresponding dissociation constants. We have observed that for uranium sulphate the formula of the complex depends only on the nature of the amine, whereas for thorium this formula varies with the amine structure. From the formulae determined and the value of the constants calculated, we have been able to establish the best conditions for uranium and thorium extraction and also for a separation of these two elements. Finally we propose an application of this study to the determination of uranium in ores, where the separation of uranium by this method is particularly easy and complete. (author) [fr

Aluminium in Infrastructures

NARCIS (Netherlands)

Maljaars, J.

2016-01-01

Aluminium alloys are used in infrastructures such as pedestrian bridges or parts of it such as handrail. This paper demonstrates that aluminium alloys are in principle also suited for heavy loaded structures, such as decks of traffic bridges and helicopter landing platforms. Recent developments in

Sulphate deposition by precipitation into Lake Ontario

Energy Technology Data Exchange (ETDEWEB)

Shaw, R W; Whelpdale, D M

1973-01-01

Measurements of sulphate concentration in precipitation from individual snow storms of several hours duration in the western Lake Ontario region indicate that approximately 9-66 mg/M/sub 2/ of SO/sub 4//sup 2 -/ is being deposited into the lake per storm. This amount is up to several times more than daily average values over long periods found by other workers. Using a mean sulphate concentration of 4 mg/l and an annual accumulation of precipitation of 760 mm, the yearly sulphate deposition by precipitation is about 0.1% of the total mass of sulphate in the lake; however, more significantly, it is of the same order of magnitude as that discharged directly into the lake by industry.

Mortar and concrete based on calcium sulphate binders

NARCIS (Netherlands)

Bakker, J.J.F.; Brouwers, H.J.H.; Fischer, H.B

2006-01-01

In this study both hemi-hydrate and anhydrite are tested as calcium sulphate binders for structural mortar and concrete. The advantage of using calcium sulphates instead of cement as a binder is the fact that the production of calcium sulphate is more environmental friendly than that of cement. For

Formation of aluminium nitride and segregation of Cu impurity atoms in aluminium implanted by high dose nitrogen ions

International Nuclear Information System (INIS)

Lin Chenglu; Hemment, P.L.F.; Li Jinhua; Zou Shichang

1994-01-01

Aluminium films with a thickness of 7000 A (containing 0.85% copper) were deposited on silicon substrates. 400 keV N 2 + or 350 keV N + ions were implanted into the aluminium films or at the interface between the aluminium and silicon, respectively. Automatic spreading resistance (ASR), Fourier transform infrared spectroscopy (FTIR) and Rutherford backscattering (RBS) and channelling were used to characterize the formation of aluminium nitride and the depth distribution of the Cu impurity in the aluminium films after ion implantation and post-annealing. The formation of a stoichiometric AlN layer with high resistance was evident from ASR, RBS analysis and FTIR measurements by the presence of the absorption band at 650 cm -1 . When the implanted nitrogen is near the interface between the aluminium and silicon, a multilayer structure can be obtained, which consists of aluminium, aluminium nitride and the silicon substrate. Cu, which is a background impurity in the deposited aluminium films, segregated into the synthesised aluminium nitride during high dose nitrogen ion implantation. This is due to irradiation-induced segregation during ion implantation. (orig.)

Ion nitriding of aluminium

International Nuclear Information System (INIS)

Fitz, T.

2002-09-01

The present study is devoted to the investigation of the mechanism of aluminium nitriding by a technique that employs implantation of low-energy nitrogen ions and diffusional transport of atoms. The nitriding of aluminium is investigated, because this is a method for surface modification of aluminium and has a potential for application in a broad spectrum of fields such as automobile, marine, aviation, space technologies, etc. However, at present nitriding of aluminium does not find any large scale industrial application, due to problems in the formation of stoichiometric aluminium nitride layers with a sufficient thickness and good quality. For the purposes of this study, ion nitriding is chosen, as an ion beam method with the advantage of good and independent control over the process parameters, which thus can be related uniquely to the physical properties of the resulting layers. Moreover, ion nitriding has a close similarity to plasma nitriding and plasma immersion ion implantation, which are methods with a potential for industrial application. (orig.)

Physicochemical and in vitro deposition properties of salbutamol sulphate/ipratropium bromide and salbutamol sulphate/excipient spray dried mixtures for use in dry powder inhalers.

Science.gov (United States)

Corrigan, Deirdre O; Corrigan, Owen I; Healy, Anne Marie

2006-09-28

The physicochemical and aerodynamic properties of spray dried powders of the drug/drug mixture salbutamol sulphate/ipratropium bromide were investigated. The in vitro deposition properties of spray dried salbutamol sulphate and the spray dried drug/excipient mixtures salbutamol sulphate/lactose and salbutamol sulphate/PEG were also determined. Spray drying ipratropium bromide monohydrate resulted in a crystalline material from both aqueous and ethanolic solution. The product spray dried from aqueous solution consisted mainly of ipratropium bromide anhydrous. There was evidence of the presence of another polymorphic form of ipratropium bromide. When spray dried from ethanolic solution the physicochemical characterisation suggested the presence of an ipratropium bromide solvate with some anhydrous ipratropium bromide. Co-spray drying salbutamol sulphate with ipratropium bromide resulted in amorphous composites, regardless of solvent used. Particles were spherical and of a size suitable for inhalation. Twin impinger studies showed an increase in the fine particle fraction (FPF) of spray dried salbutamol sulphate compared to micronised salbutamol sulphate. Co-spray dried salbutamol sulphate:ipratropium bromide 10:1 and 5:1 systems also showed an increase in FPF compared to micronised salbutamol sulphate. Most co-spray dried salbutamol sulphate/excipient systems investigated demonstrated FPFs greater than that of micronised drug alone. The exceptions to this were systems containing PEG 4000 20% or PEG 20,000 40% both of which had FPFs not significantly different from micronised salbutamol sulphate. These two systems were crystalline unlike most of the other spray dried composites examined which were amorphous in nature.

Variation in aluminium patch test reactivity over time.

Science.gov (United States)

Siemund, Ingrid; Mowitz, Martin; Zimerson, Erik; Bruze, Magnus; Hindsén, Monica

2017-11-01

Contact allergy to aluminium has been reported more frequently in recent years. It has been pointed out that positive patch test reactions to aluminium may not be reproducible on retesting. To investigate possible variations in patch test reactivity to aluminium over time. Twenty-one adults, who had previously reacted positively to aluminium, were patch tested with equimolar dilution series in pet. of aluminium chloride hexahydrate and aluminium lactate, four times over a period of 8 months. Thirty-six of 84 (43%) serial dilution tests with aluminium chloride hexahydrate and 49 of 84 (58%) serial dilution tests with aluminium lactate gave negative results. The range of reactivity varied between a negative reaction to aluminium chloride hexahydrate at 10% and/or to aluminium lactate at 12%, and a positive reaction to aluminium chloride hexahydrate at 0.1% and/or to aluminium lactate at 0.12%. The highest individual difference in test reactivity noticed was 320-fold when the two most divergent minimal eliciting concentrations were compared. The patch test reactivity to aluminium varies over time. Aluminium-allergic individuals may have false-negative reactions. Therefore, retesting with aluminium should be considered when there is a strong suspicion of aluminium contact allergy. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Sulphate reduction and vertical distribution of sulphate-reducing bacteria quantified by rRNA slot-blot hybridization in a coastal marine sediment

DEFF Research Database (Denmark)

Sahm, K.; MacGregor, BJ; Jørgensen, BB

1999-01-01

In the past, enumeration of sulphate-reducing bacteria (SRB) by cultivation-based methods generally contradicted measurements of sulphate reduction, suggesting unrealistically high respiration rates per cell. Here, we report evidence that quantification of SRB rRNA by slot-blot hybridization......, directly above the sulphate reduction maximum. Cell numbers calculated by converting the relative contribution of SRB rRNA to the percentage of DAPI-stained cells indicated a population size for SRB of 2.4-6.1 x 10(8) cells cm(-3) wet sediment. Cellular sulphate reduction rates calculated on the basis...

Recovery in aluminium

DEFF Research Database (Denmark)

Gundlach, Carsten

2006-01-01

In the present thesis the development of a unique experimental method for volume characterisation of individual embedded crystallites down to a radius of 150 nm is presented. This method is applied to in-situ studies of recovery in aluminium. The method is an extension of 3DXRD microscopy, an X...... are represented as strings. To identify the strings a combination of a 5D connected component type algorithm and multi-peak fitting was found to be superior. The first use of the method was a study of recovery of a deformed aluminium alloy (AA1050). The aluminium alloy was deformed by cold rolling to a thickness...

Persistent Skin Reactions and Aluminium Hypersensitivity Induced by Childhood Vaccines.

Science.gov (United States)

Salik, Elaha; Løvik, Ida; Andersen, Klaus E; Bygum, Anette

2016-11-02

There is increasing awareness of reactions to vaccination that include persistent skin reactions. We present here a retrospective investigation of long-lasting skin reactions and aluminium hypersensitivity in children, based on medical records and questionnaires sent to the parents. In the 10-year period 2003 to 2013 we identified 47 children with persistent skin reactions caused by childhood vaccinations. Most patients had a typical presentation of persisting pruritic subcutaneous nodules. Five children had a complex diagnostic process involving paediatricians, orthopaedics and plastic surgeons. Two patients had skin biopsies performed from their skin lesions, and 2 patients had the nodules surgically removed. Forty-two children had a patch-test performed with 2% aluminium chloride hexahydrate in petrolatum and 39 of them (92%) had a positive reaction. The persistent skin reactions were treated with potent topical corticosteroids and disappeared slowly. Although we advised families to continue vaccination of their children, one-third of parents omitted or postponed further vaccinations.

Internal friction in iron-aluminium alloys having a high aluminium content

International Nuclear Information System (INIS)

Hillairet, J.; Delaplace, J.; Silvent, A.

1966-01-01

By using a torsion pendulum to measure the internal friction of iron-aluminium alloys containing between 25 and 50 atom per cent of aluminium, it has been possible to show the existence of three damping peaks due to interstitial carbon. Their evolution is followed as a function of the carbon content, of the thermal treatment and of the aluminium content. A model based on the preferential occupation of tetrahedral sites is proposed as an interpretation of the results. A study of the Zener peak in these substitution alloys shows also that a part of the short distance disorder existing at high temperatures can be preserved by quenching. (author) [fr

Sulphate reduction and vertical distribution of sulphate-reducing bacteria quantified by rRNA slot-blot hybridization in a coastal marine sediment

DEFF Research Database (Denmark)

Sahm, K.; MacGregor, BJ; Jørgensen, BB

1999-01-01

In the past, enumeration of sulphate-reducing bacteria (SRB) by cultivation-based methods generally contradicted measurements of sulphate reduction, suggesting unrealistically high respiration rates per cell. Here, we report evidence that quantification of SRB rRNA by slot-blot hybridization...... between 18% and 25% to the prokaryotic rRNA pool. The dominant SRB were related to complete oxidizing genera (Desulphococcus, Desulphosarcina and Desulphobacterium), while Desulpho-bacter could not be detected. The vertical profile and quantity of rRNA from SRB was compared with sulphate reduction rates......, directly above the sulphate reduction maximum. Cell numbers calculated by converting the relative contribution of SRB rRNA to the percentage of DAPI-stained cells indicated a population size for SRB of 2.4-6.1 x 10(8) cells cm(-3) wet sediment. Cellular sulphate reduction rates calculated on the basis...

The determination of trace oxygen in aluminium and aluminium-silicon alloy by helium-3 activation analysis

International Nuclear Information System (INIS)

Vandecasteele, C.; Goethals, P.; Kieffer, R.; Hoste, J.

1975-01-01

The determination of oxygen in aluminium and aluminium-silicon alloy by helium-3 activation is studied. The 18 F formed from oxygen is separated by distillation followed by precipitation of leadfluorochloride. The chemical yield is determined by activation in an isotopic neutron source. Concentrations of resp. 27 and 64 ng.g -1 with a precision for a single determination of resp. 30 and 13% are found in 99.5% aluminium and in aluminium-silicon (3%) alloy. (author)

Sulphate rocks as an arena for karst development

Directory of Open Access Journals (Sweden)

Andrejchuk V.

1996-01-01

Full Text Available The rocks in which karst systems develop are most commonly composed of carbonate sulphate and chloride minerals. The sulphate minerals are quite numerous, but only gypsum and anhydrite form extensive masses in sedimentary sequences. Other minerals, which represent sulphates of K, Mg and Na, normally occur as minor beds (0.1-5.0 m, or as inclusions associated with chloride rocks. However some minerals precipitated in salt-generating basins, such as mirabilite and glauberite (typically formed in the Kara-Bogaz-Gol Gulf, salt lakes of Siberia and in China, form sequences up to 5-10 m thick where karst may develop. Due to the very high solubility of Na -sulphates, karst processes and features occurring in these rocks resemble salt karst. Thus, the term sulphate karst, although not strictly correct, is used mainly to indicate karst developed in gypsum and anhydrite.

Roll bonding of strained aluminium

DEFF Research Database (Denmark)

Staun, Jakob M.

2003-01-01

This report investigates roll bonding of pre-strained (å ~ 4) aluminium sheets to produce high strain material from high purity aluminium (99.996%) and commercial pure aluminium (99.6%). The degree of bonding is investigated by optical microscopy and ultrasonic scanning. Under the right...... of the cross rolled volume fraction is found. To further asses this effect, and the anisotropy, it is necessary to acquire knowledge about both texture and microstructure, e.g. by TEM. Roll bonding of pre-strained aluminium is found to be a possible alternative to ARB in the quest for ultra-fine grained...

Aluminium in foodstuffs and diets in Sweden.

Science.gov (United States)

Jorhem, L; Haegglund, G

1992-01-01

The levels of aluminium have been determined in a number of individual foodstuffs on the Swedish market and in 24 h duplicate diets collected by women living in the Stockholm area. The results show that the levels in most foods are very low and that the level in vegetables can vary by a factor 10. Beverages from aluminium cans were found to have aluminium levels not markedly different from those in glass bottles. Based on the results of the analysis of individual foods, the average Swedish daily diet was calculated to contain about 0.6 mg aluminium, whereas the mean content of the collected duplicate diets was 13 mg. A cake made from a mix containing aluminium phosphate in the baking soda was identified as the most important contributor of aluminium to the duplicate diets. Tea and aluminium utensils were estimated to increase the aluminium content of the diets by approximately 4 and 2 mg/day, respectively. The results also indicate that a considerable amount of aluminium must be introduced from other sources.

Constructions of aluminium electrolytic cells

International Nuclear Information System (INIS)

Galushkin, N.V.

1995-01-01

This chapter of monograph is devoted to constructions of aluminium electrolytic cells. Therefore, the general characteristic and classification of aluminium electrolytic cells was considered. The anode and cathode structure was studied. The lining of cathode casing, the process of collection of anode gases, electrolytic cell cover, and electrical insulation was studied as well. The installation and dismantling of aluminium electrolytic cells was described.

Sulphate reduction experiment: SURE-1

International Nuclear Information System (INIS)

Pedersen, K.; Arlinger, J.; Bengtsson, A.; Edlund, J.; Eriksson, L.; Hallbeck, L.; Johansson, J.; Paeaejaervi, A.; Rabe, L.

2013-11-01

It was previously concluded that opposing gradients of sulphate and methane, observations of 16S rDNA sequences displaying great similarity to those of anaerobic methane-oxidizing Archaea, and a peak in sulphide concentration in groundwater from a depth of 250-350 m in Olkiluoto, Finland, indicated proper conditions for methane oxidation with sulphate. In the present research (SURE-1), pressure-resistant, gas-tight circulating systems were constructed to enable the investigation of attached and unattached anaerobic microbial populations from a depth of 327 m in Olkiluoto under in situ pressure (2.4 MPa), diversity, dissolved gas, and hydrochemical conditions of groundwater station ONKPVA6. Three parallel flow cell cabinets were configured to allow observation of the influence on microbial metabolic activity of 11 mM methane, 11 mM methane plus 10 mM H 2 , or 2.1 mM O 2 plus 7.9 mM N 2 (i.e., air). The concentrations of these gases and of organic acids and carbon, sulphur chemistry, pH and E h , ATP, numbers of cultivable microorganisms, and total numbers of cells and bacteriophages were subsequently recorded under batch conditions for 105 d. The system containing H 2 and methane displayed microbial reduction of 0.7 mM sulphate to sulphide, while the system containing only methane produced 0.2 mM reduced sulphate. The system containing added air became inhibited and displayed no signs of microbial activity. Added H 2 and methane induced increasing numbers of lysogenic bacteriophages per cell. It appears possible that a microbial anaerobic methane-oxidizing process coupled to acetate formation and sulphate reduction may be ongoing in aquifers at a depth of 250-350 m in Olkiluoto, but clear evidence of such an AOM process was not obtained. (orig.)

Sulphate reduction experiment: SURE-1

Energy Technology Data Exchange (ETDEWEB)

Pedersen, K.; Arlinger, J.; Bengtsson, A.; Edlund, J.; Eriksson, L.; Hallbeck, L.; Johansson, J.; Paeaejaervi, A.; Rabe, L. [Microbial Analytics Sweden AB, Moelnlycke (Sweden)

2013-11-15

It was previously concluded that opposing gradients of sulphate and methane, observations of 16S rDNA sequences displaying great similarity to those of anaerobic methane-oxidizing Archaea, and a peak in sulphide concentration in groundwater from a depth of 250-350 m in Olkiluoto, Finland, indicated proper conditions for methane oxidation with sulphate. In the present research (SURE-1), pressure-resistant, gas-tight circulating systems were constructed to enable the investigation of attached and unattached anaerobic microbial populations from a depth of 327 m in Olkiluoto under in situ pressure (2.4 MPa), diversity, dissolved gas, and hydrochemical conditions of groundwater station ONKPVA6. Three parallel flow cell cabinets were configured to allow observation of the influence on microbial metabolic activity of 11 mM methane, 11 mM methane plus 10 mM H{sub 2}, or 2.1 mM O{sub 2} plus 7.9 mM N{sub 2} (i.e., air). The concentrations of these gases and of organic acids and carbon, sulphur chemistry, pH and E{sub h}, ATP, numbers of cultivable microorganisms, and total numbers of cells and bacteriophages were subsequently recorded under batch conditions for 105 d. The system containing H{sub 2} and methane displayed microbial reduction of 0.7 mM sulphate to sulphide, while the system containing only methane produced 0.2 mM reduced sulphate. The system containing added air became inhibited and displayed no signs of microbial activity. Added H{sub 2} and methane induced increasing numbers of lysogenic bacteriophages per cell. It appears possible that a microbial anaerobic methane-oxidizing process coupled to acetate formation and sulphate reduction may be ongoing in aquifers at a depth of 250-350 m in Olkiluoto, but clear evidence of such an AOM process was not obtained. (orig.)

Isotopic evolution of aqueous sulphate in northern Chile water

International Nuclear Information System (INIS)

Aravena, R.; Suzuki, O.; Fritz, P.; Pena, H.; Rauert, W.

1987-01-01

Full text: The extremely arid condition of northern Chile is the main obstacle to the present and future development of urban centres and economic activities in the region. The existing water resources are scarce. During the last decade, isotope techniques have been applied to investigate aspects such as the origin and residence time of the groundwater, these being extremely important for water development and water management. This paper presents 18 O and 34 S data in aqueous sulphate, as well as 18 O, 2 H, and 3 H from springs, rivers and groundwater samples of the Pampa del Tamarugal and Salar de Llamara basins. The principal aim of this study was to investigate the isotope evolution of the sulphate, the origin of the sulphur, the groundwater flow path, and the possibility of using the 18 O of the sulphate as a tracer for estimation of the residence time of the groundwater. Springs that have their recharge area in the high Altiplano (Salar del Huasco basin) show δ values between +5.0 per mille and +6.0 per mille for the 18 O and +5.0 per mille and +9.0 per mille for the 34 S isotope. Springs from lower altitude, show an isotope content between + 8.6 per mille and + 10.6 per mille for 18 O and +7.4 per mille and + 11.7 per mille for 34 S. The groundwaters in the Pampa aquifers, based on their hydrogen and oxygen isotope composition, are associated with different recharge areas. However, these waters show an isotope range for the sulphate similar to .he one of the springs, and no clear relationships are observed between isotope content, flow path and residence time. This pattern could be related to the poorly defined aquifer systems present in the Pampa. The Llamara groundwaters have a uniform isotope content and are the most enriched in the region (δ 18 O = -6.0 per mille and δ 2 H = -50 per mille). The isotope composition of their sulphate compares well with the Pampa groundwater, indicating a similar sulphate source. The isotope composition of gypsum

Sulphate Removal from Water by Carbon Residue from Biomass Gasification: Effect of Chemical Modification Methods on Sulphate Removal Efficiency

Directory of Open Access Journals (Sweden)

Hanna Runtti

2016-02-01

Full Text Available Sulphate removal from mine water is a problem because traditional chemical precipitation does not remove all sulphates. In addition, it creates lime sediment as a secondary waste. Therefore, an inexpensive and environmental-friendly sulphate removal method is needed in addition to precipitation. In this study, carbon residues from a wood gasification process were repurposed as precursors to a suitable sorbent for SO42- ion removal. The raw material was modified using ZnCl2, BaCl2, CaCl2, FeCl3, or FeCl2. Carbon residues modified with FeCl3 were selected for further consideration because the removal efficiency toward sulphate was the highest. Batch sorption experiments were performed to evaluate the effects of the initial pH, initial SO42- ion concentration, and contact time on sulphate removal. The removal of SO42- ions using Fe-modified carbon residue was notably higher compared with unmodified carbon residue and commercially available activated carbon. The sorption data exhibited pseudo-second-order kinetics. The isotherm analysis indicated that the sorption data of Fe-modified carbon residues can be represented by the bi-Langmuir isotherm model.

Uranium and sulphate values from carbonate leach process

International Nuclear Information System (INIS)

Berger, B.

1983-01-01

The process concerns the recovery of uraniferous and sulphur values from liquor resulting from the attack of sulphur containing uraniferous ores by an alkaline solution of sodium carbonate and/or bicarbonate. Ammonia is introduced into the liquor to convert any HCO 3 - to CO 3 2- . The neutralised liquor from this step is then contacted with an anion exchange resin to fix the uranium and sulphate ions, leaving a liquor containing ammonia, sodium carbonate and/or bicarbonate in solution. Uranium and sulphate ions are eluted with an ammonia carbonate and/or bicarbonate solution to yield a solution of ammonium uranyl carbonate complex and ammonium sulphate. The solution is subjected to thermal treatment until a suspension of precipitated ammonium uranate and/or diuranate is obtained in a solution of the ammonium sulphate. Carbon dioxide, ammonia and water vapor are driven off. The precipitated ammonium uranate and/or diuranate is then separated from the solution of ammonium sulphate and the precipitate is calcined to yield uranium trioxide and ammonia

[Association between serum aluminium level and methylation of amyloid precursor protein gene in workers engaged in aluminium electrolysis].

Science.gov (United States)

Yang, X J; Yuan, Y Z; Niu, Q

2016-04-20

To investigate the association between serum aluminium level and methylation of the promoter region of amyloid precursor protein (APP)gene in workers engaged in aluminium electrolysis. In 2012, 366 electrolysis workers in an aluminium factory were enrolled as exposure group (working years >10 and age >40 years)and divided into low-exposure group and high-exposure group based on the median serum aluminium level. Meanwhile, 102 workers in a cement plant not exposed to aluminium were enrolled as control group. Graphite furnace atomic absorption spectrometry was used to measure serum aluminium level, methylation specific PCR was used to measure the methylation rate of the promoter region of APP gene, and ELI-SA was used to measure the protein expression of APP in lymphocytes in peripheral blood. The exposure group had a significantly higher serum aluminium level than the control group (45.07 μg/L vs 30.51 μg/L, P0.05). The multivariate logistic regression analysis showed that with reference to the control group, low aluminium exposure (OR=1.86, 95% CI 1.67~3.52)and high aluminium exposure (OR=2.98, 95% CI 1.97~4.15)were risk factors for a reduced methylation rate of the promoter region of APP gene. Reduced methylation of the promoter region of APP gene may be associated with increased serum aluminium level, and downregulated methylation of the promoter region of APP gene may accelerate APP gene transcription.

The nature and significance of sulphate-rich, aluminous efflorescences from the Te Kopia geothermal field, Taupo Volcanic Zone, New Zealand

Energy Technology Data Exchange (ETDEWEB)

Martin, R.; Rodgers, K.A. [University of Auckland (New Zealand). Dept. of Geology; Browne, P.R.L. [University of Auckland (New Zealand). Dept. of Geology; University of Auckland (New Zealand). Geothermal Institute

1999-06-01

Alunogen and meta-alunogen are the dominant phases present in transient sulphate efflorescences that are the latest products of the alteration of ignimbrite country rocks in the long-lived Te Kopia geothermal field. Meta-alunogen pseudomorphs alunogen and both species occur as white, fibrous. tangled masses, as prismatic, parallel growths, and as thin. platy, crystals, 8-15 ({mu}m across, that coalesce in an open cellular network. Small (<2 mm diam.) spherical aggregates of radiating, acicular halotriechite (Fe{sub 0.51}Mg{sub 0.49}Al{sub 2}(SO{sub 4}){sub 4.22}H{sub 2}O), potash alum, mirabilite, melanterite and tschermigite are present locally. The cations needed to form these minerals derive from the host rocks with the exception of sulphur and ammonia that come from H{sub 2}S and NH{sub 3} gases ascending with steam. The particular efflorescence assemblage reflects the prevailing conditions and ionic activities of a local micro-environment. Kaolinite formed by acid sulphate alteration is now being altered by steam to yield alunogen. In turn, alunogen can react with silica, or co-dissociate with silicic acid, to form kaolinite The alternating dissolution and reprecipitation of kaolinite and alunogen moves aluminium in and through the surficial environment at Te Kopia.

Bumblebee pupae contain high levels of aluminium.

Science.gov (United States)

Exley, Christopher; Rotheray, Ellen; Goulson, David

2015-01-01

The causes of declines in bees and other pollinators remains an on-going debate. While recent attention has focussed upon pesticides, other environmental pollutants have largely been ignored. Aluminium is the most significant environmental contaminant of recent times and we speculated that it could be a factor in pollinator decline. Herein we have measured the content of aluminium in bumblebee pupae taken from naturally foraging colonies in the UK. Individual pupae were acid-digested in a microwave oven and their aluminium content determined using transversely heated graphite furnace atomic absorption spectrometry. Pupae were heavily contaminated with aluminium giving values between 13.4 and 193.4 μg/g dry wt. and a mean (SD) value of 51.0 (33.0) μg/g dry wt. for the 72 pupae tested. Mean aluminium content was shown to be a significant negative predictor of average pupal weight in colonies. While no other statistically significant relationships were found relating aluminium to bee or colony health, the actual content of aluminium in pupae are extremely high and demonstrate significant exposure to aluminium. Bees rely heavily on cognitive function and aluminium is a known neurotoxin with links, for example, to Alzheimer's disease in humans. The significant contamination of bumblebee pupae by aluminium raises the intriguing spectre of cognitive dysfunction playing a role in their population decline.

Long-term effects of aluminium dust inhalation.

Science.gov (United States)

Peters, Susan; Reid, Alison; Fritschi, Lin; de Klerk, Nicholas; Musk, A W Bill

2013-12-01

During the 1950s and 1960s, aluminium dust inhalation was used as a potential prophylaxis against silicosis in underground miners, including in Australia. We investigated the association between aluminium dust inhalation and cardiovascular, cerebrovascular and Alzheimer's diseases in a cohort of Australian male underground gold miners. We additionally looked at pneumoconiosis mortality to estimate the effect of the aluminium therapy. SMRs and 95% CI were calculated to compare mortality of the cohort members with that of the Western Australian male population (1961-2009). Internal comparisons on duration of aluminium dust inhalation were examined using Cox regression. Aluminium dust inhalation was reported for 647 out of 1894 underground gold miners. During 42 780 person-years of follow-up, 1577 deaths were observed. An indication of increased mortality of Alzheimer's disease among miners ever exposed to aluminium dust was found (SMR=1.38), although it was not statistically significant (95% CI 0.69 to 2.75). Rates for cardiovascular and cerebrovascular death were above population levels, but were similar for subjects with or without a history of aluminium dust inhalation. HRs suggested an increasing risk of cardiovascular disease with duration of aluminium dust inhalation (HR=1.02, 95% CI 1.00 to 1.04, per year of exposure). No difference in the association between duration of work underground and pneumoconiosis was observed between the groups with or without aluminium dust exposure. No protective effect against silicosis was observed from aluminium dust inhalation. Conversely, exposure to aluminium dust may possibly increase the risk of cardiovascular disease and dementia of the Alzheimer's type.

Design and analysis of aluminium brdiges

NARCIS (Netherlands)

Soetens, F.; Straalen, IJ.J. van

2004-01-01

Applications of aluminium have grown considerably in building and civil engineering the last decade, which is due to various aspects: light weight, durability and maintenance, use of extrusions. The paper starts with a short history of aluminium bridges and then focuses on aluminium bridges in the

Acute aluminium phosphide poisoning, what is new?

Directory of Open Access Journals (Sweden)

Yatendra Singh

2014-01-01

Full Text Available Aluminium phosphide (AlP is a cheap solid fumigant and a highly toxic pesticide that is commonly used for grain preservation. AlP has currently generated interest with increasing number of cases in the past four decades because of its increased use for agricultural and nonagricultural purposes, and also its easy availability in the markets has led to its increased misuse to commit suicide. Ingestion is usually suicidal in intent, uncommonly accidental and rarely homicidal. The poison affects all systems, shock, cardiac arrhythmias with varied ECG changes and gastrointestinal features being the most prominent. Diagnosis is made on the basis of clinical suspicion, a positive silver nitrate paper test to phosphine, and gastric aspirate and viscera biochemistry. Treatment includes early gastric lavage with potassium permanganate or a combination of coconut oil and sodium bicarbonate, administration of charcoal and palliative care. Specific therapy includes intravenous magnesium sulphate and oral coconut oil. Unfortunately, the lack of a specific antidote Results in very high mortality and the key to treatment lies in rapid decontamination and institution of resuscitative measures. This article aims to identify the salient features and mechanism of AlP poisoning along with its management strategies and prognostic variables.

Sulphate Incorporation in Borosilicate Glasses and Melts: a Kinetic Approach

Energy Technology Data Exchange (ETDEWEB)

Lenoir, M. [CEA, DEN, Laboratoire d' etude et de Developpement de Matrices de Conditionnement, Centre de Marcoule, 30207 Bagnols-sur-Ceze (France); Physique des Mineraux et Magmas, UMR 7047, CNRS- Institut de Physique du Globe de Paris, 7 place Jussieu, 75252 Paris 05 (France); Grandjean, A. [Institut de Chimie Separative de Marcoule, UMR 5257, Laboratoire des Nanomateriaux Autoreparants, Marcoule, 30207 Bagnols-sur-Ceze (France); Dussossoy, J.L. [CEA, DEN, Laboratoire d' etude et de Developpement de Matrices de Conditionnement, Centre de Marcoule, 30207 Bagnols-sur-Ceze (France); Neuville, D.R. [Physique des Mineraux et Magmas, UMR 7047, CNRS- Institut de Physique du Globe de Paris, 7 place Jussieu, 75252 Paris 05 (France)

2008-07-01

The kinetics of sulphate departure in a sodium borosilicate melt were studied using in situ Raman spectroscopy. This technique allows the quantification of the amount of sulphate dissolved in a borosilicate glass as a function of heating time by comparison with measurements obtained by microprobe wavelength dispersive spectrometry. To quantify the sulphate content obtained with Raman spectroscopy, the integrated intensity of the sulphate band at 990 cm{sup -1} was scaled to the sum of the integrated bands between 800 and 1200 cm{sup -1}, bands that are assigned to Qn silica units on the basis of previous literature. Calibration curves were then determined for two different samples. An evaluation of the kinetics of departure of sulphate could thus be made as a function of the viscosity of the borosilicate glass, showing that the kinetics were controlled by the diffusion of sulphate and its volatilization from the melt. This experimental method allows in situ measurements of sulphate content at high temperature which cannot be obtained by any other simple technique. (authors)

Recycling of aluminium swarf by direct incorporation in aluminium melts

OpenAIRE

Puga, Hélder; Barbosa, J.; Soares, Delfim; Silva, Filipe Samuel; Ribeiro, Carlos Silva

2009-01-01

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 recovery rate and dross production was experimentally studied and evaluated...

Irradiation damage in aluminium single crystals produced by 50-keV aluminium and copper ions

DEFF Research Database (Denmark)

Henriksen, L.; Johansen, A.; Koch, J.

1968-01-01

Aluminium single crystals, thin enough to be examined by electron microscopy, have been irradiated with 50-keV aluminium and copper ions. The irradiation fluxes were in the range 1011–1014 cm−2 s−1 and the doses were from 6 × 1012 to 6 × 1014 cm−2. Irradiation along either a or a direction produces...... rows of dislocation loops all lying parallel to one particular direction. If the aluminium target is quenched from 600 °C and annealed at room temperature prior to irradiation with aluminium ions, the rows of loops are suppressed. The amount of damage observed is considerably less than would...

Gastrointestinal tract wall visualization and distention during abdominal and pelvic multidetector CT with a neutral barium sulphate suspension: comparison with positive barium sulphate suspension and with water.

Science.gov (United States)

Oliva, M R; Erturk, S M; Ichikawa, T; Rocha, T; Ros, P R; Silverman, S G; Mortele, K J

2012-01-01

When examining patients with contrast-enhanced multidetector-row CT, we determined if the stomach and small bowel were visualized and distended better with a neutral barium sulphate suspension than with positive barium sulphate suspension or water. After obtaining approval from our institutional review board, 156 patients (women: 84; mean age: 54 yrs) with no history of gastrointestinal tract disease were randomized prospectively to receive orally either 900 ml of neutral (0.1% w/v) barium sulphate suspension (n = 53), 900 ml of positive (2.1% w/v) barium sulphate suspension (n = 53), or 900 ml of water (n = 50), prior to undergoing contrast-enhanced abdominal and pelvic multidetector-row CT. Two independent radiologists evaluated the stomach, and small bowel, for luminal distension and wall visualization, using a five point scale. Results were compared using Kruskal-Wallis and Mann-Whitney U tests. The walls of the stomach, and small bowel were visualized better in patients who were administered neutral barium sulphate suspension than those who were administered either positive barium sulphate suspension (p barium sulphate suspension, the stomach and small bowel were distended better compared to patients administered water (p barium sulphate suspension (p contrast-enhanced abdominal and pelvic multidetector-row CT, orally administered neutral barium sulphate suspension allows the gastrointestinal tract to be visualized and distended better than either positive barium sulphate suspension, or water.

Effects of agmatine sulphate on facial nerve injuries.

Science.gov (United States)

Surmelioglu, O; Sencar, L; Ozdemir, S; Tarkan, O; Dagkiran, M; Surmelioglu, N; Tuncer, U; Polat, S

2017-03-01

To evaluate the effect of agmatine sulphate on facial nerve regeneration after facial nerve injury using electron and light microscopy. The study was performed on 30 male Wistar albino rats split into: a control group, a sham-treated group, a study control group, an anastomosis group, and an anastomosis plus agmatine sulphate treatment group. The mandibular branch of the facial nerve was dissected, and a piece was removed for histological and electron microscopic examination. Regeneration was better in the anastomosis group than in the study control group. However, the best regeneration findings were seen in the agmatine sulphate treatment group. There was a significant difference between the agmatine group and the others in terms of median axon numbers (p Agmatine sulphate treatment with anastomosis in traumatic facial paralysis may enhance nerve regeneration.

Laser welding of aluminium alloys

OpenAIRE

Forsman, Tomas

2000-01-01

This thesis treats laser welding of aluminium alloys from a practical perspective with elements of mathematical analysis. The theoretical work has in all cases been verified experimentally. The aluminium alloys studied are from the 5xxx and 6xxx groups which are common for example in the automotive industry. Aluminium has many unique physical properties. The properties which more than others have been shown to influence the welding process is its high reflection, high thermal conductivity, lo...

The reducibility of sulphuric acid and sulphate in aqueous solution

International Nuclear Information System (INIS)

Grauer, R.

1991-07-01

In connection with the Swedish project for final storage of spent fuel elements it was necessary to assess whether dissolved sulphate can corrode the copper canister. A simple reaction between copper and sulphate is thermodynamically impossible, but copper can react to give copper sulphide if an additional electron donor such as iron(II) is available. The problem was extended to the more general question of the reducibility of sulphur(VI) in dilute aqueous solution. Chemical reduction of sulphate does not take place in dilute solution at temperatures below 100 o C. In experiments on the reduction of sulphates under hydrothermal conditions a reaction only takes place at temperatures above 275-300 o C. The oxidising action of sulphuric acid on metals becomes perceptible only at acid concentrations over 45-50%. In experiments on the cathodic reduction of 74% sulphuric acid the formation of hydrogen sulphide and elementary sulphur starts, depending on the current density, at 50-130 o C, and polarographic measurements suggest that the reducible species is not the hydrogen sulphate ion but molecular sulphuric acid. The resistance of copper to oxygen-free sulphuric acid up to a concentration of 60% is well-known. Numerous processes in industrial electrochemistry take place in sulphuric acid or sulphate electrolytes. The reversible metal/metal-sulphate electrodes of lead and cadmium are unstable relative to the corresponding metal sulphides. Nevertheless the reversible lead sulphate electrode does not fail from sulphide formation. All these facts confirm that sulphur(VI) in dilute solution is completely inert towards chemical reducing agents and also to cathodic reduction. Thus corrosion of copper by sulphate under final-storage conditions and in the absence of sulphate reducing bacteria can be almost certainly be ruled out. (author) 5 figs., 85 refs

Anthropogenic influence on the distribution of tropospheric sulphate aerosol

Energy Technology Data Exchange (ETDEWEB)

Langner, J; Rodhe, H; Crutzen, P J; Zimmermann, P [Swedish Meteorological and Hydrological Institute, Norrkoeping (Sweden)

1992-10-22

Human activities have increased global emissions of sulphur gases by about a factor of three during the past century, leading to increased sulphate aerosol concentrations, mainly in the Northern Hemisphere. Sulphate aerosols can affect the climate directly, by increasing the backscattering of solar radiation in cloud-free air, and indirectly, by providing additional cloud condensation nuclei. Here a global transport-chemistry model is used to estimate the changes in the distribution of tropospheric sulphate aerosol and deposition of non-seasalt sulphur that have occurred since pre-industrial times. The increase in sulphate aerosol concentration is small over the Southern Hemisphere oceans, but reaches a factor of 100 over northern Europe in winter. Calculations indicate, however, that at most 6% of the anthropogenic sulphur emissions is available for the formation of new aerosol particles. This is because about one-half of the sulphur dioxide is deposited on the Earth's surface, and most of the remainder is oxidized in cloud droplets so that the sulphate becomes associated with pre-existing particles. Even so, the rate of formation of new sulphate particles may have doubled since pre-industrial times. 18 refs., 3 figs.

Developments in the US aluminium recycling industry

Energy Technology Data Exchange (ETDEWEB)

Bolling, R N

1983-06-01

In the USA scrap recovery of aluminium has gained in importance since the war. Today its amounts to about 32% of total supply. On the other hand primary production in the US seems to have hardly any expansion possibilities. The development of the aluminium beverage can is the clearest example for recycling growth. The increased use of aluminium in passenger cars has led to very close technical and local relations of aluminium foundries and secondary smelters. The changing nature of the aluminium business caused by the growth of recycling should be recognized and made use of.

Process for the manufacture of plates containing neutron poison from aluminium and aluminium alloys

International Nuclear Information System (INIS)

Bauer, G.; Pollmann, E.; Srostlik, P.

1985-01-01

A process for guaranteeing sub-critical arrangements of nuclear fuel in tranport and/or storage containers is described, in which a homogeneous distribution of neutron poison in the aluminium matrix is guaranteed. A homogeneous mixture of aluminium powder and neutron poison powder is produced, this is pressed into plates in several stages, dried and made into hollow aluminium profiles of rectangular cross-section. The open ends of the hollow profile are then closed and this is rolled to the required dimension at 470-500 0 C. (orig./HP) [de

Chapter 1. Economic aspects of aluminium production

International Nuclear Information System (INIS)

Yanko, E.A.; Kabirov, Sh.O.; Safiev, Kh.; Azizov, B.S.; Mirpochaev, Kh.A.

2011-01-01

This article is devoted to economic aspects of aluminium production. Therefore, the perspectives of development of aluminium production, the base components of aluminium cost and economic security of enterprise are considered in this chapter.

Aluminium and nickel in human albumin solutions

DEFF Research Database (Denmark)

Gammelgaard, Bente; Sandberg, E

1989-01-01

Five different brands of commercially available human albumin solutions for infusion were analysed for their aluminium and nickel contents by atomic absorption spectrometry. The aluminium concentrations ranged from 12 micrograms/l to 1109 micrograms/l and the nickel concentrations ranged from 17...... micrograms/l to 77 micrograms/l. Examination of the aluminium and nickel contents of the constituents for the production of one brand showed too low levels to explain the final contamination of the product. By following the aluminium and nickel concentrations of the same brand during the production...... of a batch of albumin solution, filtration was shown to contribute to contamination, although the largest increase in aluminium as well as nickel concentrations appeared during the bulk concentrating process. To avoid health risks to certain patients, regulations should be established requiring aluminium...

Aluminium beverage can recycling

Energy Technology Data Exchange (ETDEWEB)

Lewinski, A von

1985-08-01

Canned beverages have become a controversial issue in this era of ecological sensitivity. METALL has already discussed the problem of can recycling. The present article discusses the technical aspects of aluminium can recycling. Two further articles will follow on aluminium can recycling in North America and on the results of European pilot projects.

Controlling Barium Sulphate Scale Deposition Problems in an unbleached Kraft Paper Mill

CSIR Research Space (South Africa)

Sithole, Bruce

2015-06-01

Full Text Available Troubleshooting of scale deposits and defects in paper samples showed that the problem was caused by barium sulphate and calcium sulphate scales. However, it was ascertained that barium sulphate was more of a concern than calcium sulphate...

Photochemical preparation of aluminium oxide layers via vacuum ultraviolet irradiation of a polymeric hexanoato aluminium complex

International Nuclear Information System (INIS)

Wennrich, L.; Khalil, H.; Bundesmann, C.; Decker, U.; Gerlach, J.W.; Helmstedt, U.; Manova, D.; Naumov, S.; Prager, L.

2013-01-01

By means of photochemical conversion of thin layers of a polymeric hexanoato aluminium complex as the precursor, thin aluminium oxide layers were prepared onto silicon wafers. The precursor compound was synthesized and characterized by several analytical techniques like NMR, FTIR, XPS, ICP, and found to be a polymeric aluminium-containing coordination compound which has been proposed to be a hydroxo-bridged aluminium chain with pendant hexanoyl side-chains ascertained as catena-poly[{di(κ-O,O-hexanoato)aluminium}(μ-hydroxo)] (PHAH). Thin layers deposited from a solution of PHAH in toluene onto silicon wafers were irradiated using VUV radiation from a xenon excimer lamp. The layers were characterized by XPS, XRD, XRR, and spectroscopic ellipsometry. VUV radiation with a radiant exposure of E = 36 J cm −2 led to almost carbon-free amorphous layers with a composition close to that of alumina having a density of about 2.1 g cm −3 . Thus, using the example of a polymeric aluminium complex, the potential of the photochemical conversion of metal complexes into oxides could be shown as an alternative method, in addition to sol–gel techniques, for the generation of thin plane metal-oxide layers at normal temperature and pressure. Highlights: ► A polymeric aluminium complex was synthesized and characterized by NMR, FTIR, XPS and ICP. ► Thin layers of the compound were irradiated using vacuum-UV radiation and converted to AlO x . ► Quantum-chemical calculations explain the conversion mechanism.

Aluminium-27 n.m.r. studies of aluminium fluoro complexes in dichloromethane solution: evidence for tetrafluoroaluminate anion

International Nuclear Information System (INIS)

Colton, R.; Eller, P.G.

1989-01-01

Mixed aluminium chloro/fluoro anions are formed in dichloromethane solution by the interaction of AlCl 3 and [Ph 3 PhCH 2 P] [H 2 F 3 ]. Aluminium-27 n.m.r. studies are restricted to the stoichiometric ranges F/Al from 1:1 to 3:1 and F/Al>8:1. Between these limits rapid precipitation reactions occur. In the fluoride-rich stoichiometric range there is rapid exchange on the n.m.r. time scale between the aluminium fluoro anion and free fluoride, so that a direct identification of the species by the multiplicity of the resonance is not possible. Indirect evidence strongly suggests that the aluminium species is [AlF 4 ] - . In the F/Al stoichiometry range from 1:1 to 3:1 aluminium-27 resonances were observed for all the other possible [AlCl χ F 4-χ ] - species. Studies on the aluminium iodo/fluoro system support the identification of [AlF 4 ] - , but the system is labile and the mixed iodo/fluoro species undergo rapid disproportionation. 12 refs., 1 fig

Effect of hydrogen on aluminium and aluminium alloys: A review

DEFF Research Database (Denmark)

Ambat, Rajan; Dwarakadasa, E.S.

1996-01-01

Susceptibility of aluminium and its alloys towards hydrogen embrittlement has been well established. Still a lot of confusion exists on the question of transport of hydrogen and its possible role in stress corrosion cracking. This paper reviews some of the fundamental properties of hydrogen...... in aluminium and its alloys and its effect on mechanical properties. The importance of hydrogen embrittlement over anodic dissolution to explain the stress corrosion cracking mechanism of these alloys is also examined in considerable detail. The various experimental findings concerning the link between...

Treatment with magnesium sulphate in pre-term birth

DEFF Research Database (Denmark)

Wolf, Hans; Hegaard, H K; Greisen, G

2012-01-01

Premature birth increases a child's risk of cerebral palsy and death. The aim of this work is to investigate the association between treatment with magnesium sulphate during premature deliveries and infants' cerebral palsy and mortality through a meta-analysis of observational studies....... A comprehensive search of the Cochrane Library, EMBASE and the PubMed database from their inceptions to 1 October, 2010 using the keywords 'magnesium sulphate, children/infant/pre-term/premature and cerebral palsy/mortality/morbidity/adverse effects/outcome' identified 11 reports of observational studies. Two...... authors working independently extracted the data. A meta-analysis of the data found an association between magnesium sulphate treatment and a significantly reduced risk of mortality (RR 0.73; 95% CI 0.61-0.89) and cerebral palsy (OR 0.64; 95% CI 0.47-0.89). Antenatal treatment with magnesium sulphate...

Raw materials for aluminium production

International Nuclear Information System (INIS)

Galushkin, N.V.

1995-01-01

This chapter of monograph is devoted to to raw materials which used in aluminium production. Therefore, the using of alumina, and fluoride salts in aluminium production was considered. The physical properties of alumina were studied.

Electron beam welding of aluminium components

International Nuclear Information System (INIS)

Maajid, Ali; Vadali, S.K.; Maury, D.K.

2015-01-01

Aluminium is one of the most widely used materials in industries like transportation, shipbuilding, manufacturing, aerospace, nuclear, etc. The challenges in joining of aluminium are distortion, cleanliness and quality. Main difficulties faced during fusion welding of aluminium components are removal of surface oxide layer, weld porosity, high heat input requirement, distortion, hot cracking, etc. Physical properties of aluminium such as its high thermal conductivity, high coefficient of thermal expansion, no change in colour at high temperature, large difference in the melting points of the metal and its oxide (∼ 1400 °C) compound the difficulties faced during welding. Gas Tungsten Arc Welding (GTAW), Gas Metal Arc Welding (GMAW), Plasma Arc Welding (PAW), etc are generally used in industries for fusion welding of aluminium alloys. However in case of thicker jobs the above processes are not suitable due to requirements of elaborate edge preparation, preheating of jobs, fixturing to prevent distortion, etc. Moreover, precise control over the heat input during welding and weld bead penetration is not possible with above processes. Further, if heat sensitive parts are located near the weld joint then high energy density beam welding process like Electron Beam Welding (EBW) is the best possible choice for aluminium welding.This paper discusses EB welding of aluminium components, typical geometry of components, selection/optimization of welding parameters, problems faced during standardization of welding and process parameters and their remedies etc.

Measured and simulated effects of sophisticated drainage techniques on groundwater level and runoff hydrochemistry in areas of boreal acid sulphate soils

Directory of Open Access Journals (Sweden)

I. BÄRLUND

2008-12-01

Full Text Available To abate the environmental problems caused by the severe acidity and high metal concentrations in rivers draining acid sulphate (AS soils of Western Finland, control drainage (CD and lime filter drainage (LFD, and their combination, were investigated. The effectiveness of these best management practices (BMP’s on drainage water quality was studied on plot scale in two locations. In Ilmajoki, where the sulphidic materials are more than 2 m below the soil surface, CD efficiently reduced the concentrations of sulphate, aluminium, manganese and iron concentrations and to some extent also increased the pH of the drainage waters. LFD, in contrast, effectively reduced the drainage water acidity and raised the pH level. Decrease of the groundwater level owing to strong evapotranspiration in summer could, however, not be properly prevented by CD. In Mustasaari where sulphidic materials were as shallow as 1 m below soil surface, the positive effects of LFD recognised in Ilmajoki were hardly seen. This shows, that the tested BMP’s work properly, and can thus be recommended, for intensively artificially drained AS soils like in Ilmajoki where most of the acidity has already been transported to watercourses. LFD can, however, not be recommended for as yet poorly leached and thus particularly problematic AS soils like in Mustasaari. This is, of course, a drawback of the tested BMP, as it is not effective for the soils which would need it most. The field data were tentatively utilised to test the performance of the HAPSU (Ionic Flow Model for Acid Sulphate Soils simulation model developed to estimate the loads of harmful substances from AS soils.;

Sulphate in Liquid Nuclear Waste: from Production to Containment

Energy Technology Data Exchange (ETDEWEB)

Lenoir, M.; Grandjean, A.; Ledieu, A.; Dussossoy, J.L.; Cau Dit Coumes, C.; Barre, Y.; Tronche, E. [CEA Marcoule, DEN/DTCD/SECM/LDMC, Batiment 208 BP17171, Bagnols sur Ceze, 30207 (France)

2009-06-15

Nuclear industry produces a wide range of low and intermediate level liquid radioactive wastes which can include different radionuclides such as {sup 90}Sr. In La Hague reprocessing plant and in the nuclear research centers of CEA (Commissariat a l'Energie Atomique), the coprecipitation of strontium with barium sulphate is the technique used to treat selectively these contaminated streams with the best efficiency. After the decontamination process, low and intermediate level activity wastes incorporating significant quantities of sulphate are obtained. The challenge is to find a matrix easy to form and with a good chemical durability which is able to confine this kind of nuclear waste. The current process used to contain sulphate-rich nuclear wastes is bituminization. However, in order to improve properties of containment matrices and simplify the process, CEA has chosen to supervise researches on other materials such as cements or glasses. Indeed, cements are widely used for the immobilization of a variety of wastes (low and intermediate level wastes) and they may be an alternative matrix to bitumen. Even if Portland cement, which is extensively used in the nuclear industry, presents some disadvantages for the containment of sulphate-rich nuclear wastes (risk of swelling and cracking due to delayed ettringite formation), other cement systems, such as calcium sulfo-aluminate binders, may be valuable candidates. Another matrix to confine sulphate-rich waste could be the glass. One of the advantages of this material is that it could also immobilize sulphate containing high level nuclear waste which is present in some countries. This waste comes from the use of ferrous sulfamate as a reducing agent for the conversion of Pu{sup 4+} to Pu{sup 3+} in the partitioning stage of the actinides during reprocessing. Sulphate solubility in borosilicate glasses has already been studied in CEA at laboratory and pilot scales. At a pilot scale, low level liquid waste has been

Chapter 2. Theoretical aspects of aluminium production

International Nuclear Information System (INIS)

Yanko, E.A.; Kabirov, Sh.O.; Safiev, Kh.; Azizov, B.S.; Mirpochaev, Kh.A.

2011-01-01

This article is devoted to theoretical aspects of aluminium production. Thus, the electrochemistry of electrolysis process, calculation of base industrial indicators of aluminium electrolytic cell, and processes occurring on anode and cathode were considered. Factors, which increase the current output and electrolytic cell productivity were studied. The side effects, including anode effect, sodium extraction on cathode, aluminium dissolution in the electrolyte, aluminium carbide formation, and influence of admixtures in the electrolyte were studied as well.

Post traumatic tetanus and role magnesium sulphate

International Nuclear Information System (INIS)

Sikendr, R.I.; Samad, B.U.; Memon, M.I.

2009-01-01

Tetanus is a life threatening disease. Reported mortality for tetanus is 15-39%. Conventional treatment includes heavy sedation and artificial ventilation. Complications resulting from long term heavy sedation and artificial ventilation contribute to 60% of the total mortality caused by tetanus. In this study magnesium sulphate was used to reduce the need for sedation and artificial ventilation. Objectives of this prospective study were to determine the role of magnesium sulphate in post traumatic tetanus. The study was carried out in surgical Intensive Care at Pakistan Institute of Medical Sciences (PIMS), Islamabad from Jan 2004 to Dec 2007. Forty-four patients presented during this period and 33 patients were included in the study. All patients had tracheostomy done within 48 hours. Every patient was started Magnesium Sulphate therapy for control of spasms after sending baseline investigations. Patients were given ventilatory support when needed. All data was entered in well structured proforma. SPSS-10 was used to analyse data. Thirty-three patients were included in the study and all patients were given magnesium sulphate. Out of these, 45.5% cases were grade 4 tetanus, 73.6% and 63.3% cases did not require artificial ventilation and additional sedation respectively, 51.1% patients remained free of complications of tetanus. Overall mortality was 30.3%. Use of Magnesium Sulphate is safe and reduces the need for sedation and artificial ventilation in high grade tetanus thus contributing to survival benefit in adult post-traumatic tetanus cases. (author)

Aluminium in brain tissue in familial Alzheimer's disease.

Science.gov (United States)

Mirza, Ambreen; King, Andrew; Troakes, Claire; Exley, Christopher

2017-03-01

The genetic predispositions which describe a diagnosis of familial Alzheimer's disease can be considered as cornerstones of the amyloid cascade hypothesis. Essentially they place the expression and metabolism of the amyloid precursor protein as the main tenet of disease aetiology. However, we do not know the cause of Alzheimer's disease and environmental factors may yet be shown to contribute towards its onset and progression. One such environmental factor is human exposure to aluminium and aluminium has been shown to be present in brain tissue in sporadic Alzheimer's disease. We have made the first ever measurements of aluminium in brain tissue from 12 donors diagnosed with familial Alzheimer's disease. The concentrations of aluminium were extremely high, for example, there were values in excess of 10μg/g tissue dry wt. in 5 of the 12 individuals. Overall, the concentrations were higher than all previous measurements of brain aluminium except cases of known aluminium-induced encephalopathy. We have supported our quantitative analyses using a novel method of aluminium-selective fluorescence microscopy to visualise aluminium in all lobes of every brain investigated. The unique quantitative data and the stunning images of aluminium in familial Alzheimer's disease brain tissue raise the spectre of aluminium's role in this devastating disease. Copyright © 2016 The Authors. Published by Elsevier GmbH.. All rights reserved.

Recent developments in advanced aircraft aluminium alloys

International Nuclear Information System (INIS)

Dursun, Tolga; Soutis, Costas

2014-01-01

Highlights: • To compete with composites, performance of aluminium alloys should be increased. • Al–Li alloys have higher strength, fracture and fatigue/corrosion resistance. • Improvements of aerospace Al alloys are due to optimised solute content and ratios. • In selecting new materials, there should be no reduction in the level of safety. • The use of hybrid materials could provide additional opportunities for Al alloys. - Abstract: Aluminium alloys have been the primary material for the structural parts of aircraft for more than 80 years because of their well known performance, well established design methods, manufacturing and reliable inspection techniques. Nearly for a decade composites have started to be used more widely in large commercial jet airliners for the fuselage, wing as well as other structural components in place of aluminium alloys due their high specific properties, reduced weight, fatigue performance and corrosion resistance. Although the increased use of composite materials reduced the role of aluminium up to some extent, high strength aluminium alloys remain important in airframe construction. Aluminium is a relatively low cost, light weight metal that can be heat treated and loaded to relatively high level of stresses, and it is one of the most easily produced of the high performance materials, which results in lower manufacturing and maintenance costs. There have been important recent advances in aluminium aircraft alloys that can effectively compete with modern composite materials. This study covers latest developments in enhanced mechanical properties of aluminium alloys, and high performance joining techniques. The mechanical properties on newly developed 2000, 7000 series aluminium alloys and new generation Al–Li alloys are compared with the traditional aluminium alloys. The advantages and disadvantages of the joining methods, laser beam welding and friction stir welding, are also discussed

Toxicity of dissolved and precipitated aluminium to marine diatoms.

Science.gov (United States)

Gillmore, Megan L; Golding, Lisa A; Angel, Brad M; Adams, Merrin S; Jolley, Dianne F

2016-05-01

Localised aluminium contamination can lead to high concentrations in coastal waters, which have the potential for adverse effects on aquatic organisms. This research investigated the toxicity of 72-h exposures of aluminium to three marine diatoms (Ceratoneis closterium (formerly Nitzschia closterium), Minutocellus polymorphus and Phaeodactylum tricornutum) by measuring population growth rate inhibition and cell membrane damage (SYTOX Green) as endpoints. Toxicity was correlated to the time-averaged concentrations of different aluminium size-fractions, operationally defined as aluminium exposure varied between diatom species. C. closterium was the most sensitive species (10% inhibition of growth rate (72-h IC10) of 80 (55-100)μg Al/L (95% confidence limits)) while M. polymorphus (540 (460-600)μg Al/L) and P. tricornutum (2100 (2000-2200)μg Al/L) were less sensitive (based on measured total aluminium). Dissolved aluminium was the primary contributor to toxicity in C. closterium, while a combination of dissolved and precipitated aluminium forms contributed to toxicity in M. polymorphus. In contrast, aluminium toxicity to the most tolerant diatom P. tricornutum was due predominantly to precipitated aluminium. Preliminary investigations revealed the sensitivity of C. closterium and M. polymorphus to aluminium was influenced by initial cell density with aluminium toxicity significantly (paluminium toxicity to diatoms do not involve compromising the plasma membrane. These results indicate that marine diatoms have a broad range in sensitivity to aluminium with toxic mechanisms related to both dissolved and precipitated aluminium. Copyright © 2016 Elsevier B.V. All rights reserved.

Interdependent action of nickel sulphate and X-rays on human lymphoblastoid leukeamic cells

International Nuclear Information System (INIS)

Bensimon, Jacques

1977-01-01

In a first experiment, cells were cultured in media supplemented by nickel sulphate, irradiated in same media and cultured in same media after irradiation. In a second experiment, cells were cultured during 18hrs. in media supplemented by nickel sulphate, and then cells were washed and cultured in normal media where they were irradiated. The nickel sulphate toxicity appears as a creasing function of the nickel sulphate concentration and the nickel sulphate action endurance. The nickel sulphate toxic effect is amplified by X-rays. This amplification is a time function that depends on the X-ray dose, nickel sulphate concentration and period of time from the outset of culture to the irradiation. The nickel sulphate toxic effect appears faster when nickel works after X-rays [fr

Lactobacillus plantarum CCFM639 alleviates aluminium toxicity.

Science.gov (United States)

Yu, Leilei; Zhai, Qixiao; Liu, Xiaoming; Wang, Gang; Zhang, Qiuxiang; Zhao, Jianxin; Narbad, Arjan; Zhang, Hao; Tian, Fengwei; Chen, Wei

2016-02-01

Aluminium (Al) is the most abundant metal in the earth's crust. Al exposure can cause a variety of adverse physiological effects in humans and animals. Our aim was to demonstrate that specific probiotic bacteria can play a special physiologically functional role in protection against Al toxicity in mice. Thirty strains of lactic acid bacteria (LAB) were tested for their aluminium-binding ability, aluminium tolerance, their antioxidative capacity, and their ability to survive the exposure to artificial gastrointestinal (GI) juices. Lactobacillus plantarum CCFM639 was selected for animal experiments because of its excellent performance in vitro. Forty mice were divided into four groups: control, Al only, Al plus CCFM639, and Al plus deferiprone (DFP). CCFM639 was administered at 10(9) CFU once daily for 10 days, followed by a single oral dose of aluminium chloride hexahydrate at 5.14 mg aluminium (LD50) for each mouse. The results showed that CCFM639 treatment led to a significant reduction in the mortality rates with corresponding decrease in intestinal aluminium absorption and in accumulation of aluminium in the tissues and amelioration of hepatic histopathological damage. This probiotic treatment also resulted in alleviation of hepatic, renal, and cerebral oxidative stress. The treatment of L. plantarum CCFM639 has potential as a therapeutic dietary strategy against acute aluminium toxicity.

Aluminium, gallium, indium and thallium

International Nuclear Information System (INIS)

Brown, Paul L.; Ekberg, Christian

2016-01-01

Aluminium can exist in a number of oxyhydroxide mineral phases including corundum, diaspore, boehmite and gibbsite. The stability constants at zero ionic strength reported for Al(OH) 3 (aq) vary linearly with respect to the inverse of absolute temperature. A full suite of thermodynamic parameters is available for all aluminium phases and hydrolysis species. Gallium hydrolyses to a greater extent than aluminium, with the onset of hydrolysis reactions occurring just above a pHof 1. In fact, even though aluminium has the smallest ionic radius of this series of metals, it has the weakest hydrolysis species and oxide/hydroxide phases.This is due to the presence of stabilising d-orbitals in the heavier metals, gallium, indium and thallium(III). There are few available data for the stability constants of indium(III) hydrolysis species. Of those that are available, the range in the proposed stability constants covers many orders of magnitude.

Process development for elemental recovery from PGM tailings by thermochemical treatment: Preliminary major element extraction studies using ammonium sulphate as extracting agent.

Science.gov (United States)

Mohamed, Sameera; van der Merwe, Elizabet M; Altermann, Wladyslaw; Doucet, Frédéric J

2016-04-01

Mine tailings can represent untapped secondary resources of non-ferrous, ferrous, precious, rare and trace metals. Continuous research is conducted to identify opportunities for the utilisation of these materials. This preliminary study investigated the possibility of extracting major elements from South African tailings associated with the mining of Platinum Group Metals (PGM) at the Two Rivers mine operations. These PGM tailings typically contain four major elements (11% Al2O3; 12% MgO; 22% Fe2O3; 34% Cr2O3), with lesser amounts of SiO2 (18%) and CaO (2%). Extraction was achieved via thermochemical treatment followed by aqueous dissolution, as an alternative to conventional hydrometallurgical processes. The thermochemical treatment step used ammonium sulphate, a widely available, low-cost, recyclable chemical agent. Quantification of the efficiency of the thermochemical process required the development and optimisation of the dissolution technique. Dissolution in water promoted the formation of secondary iron precipitates, which could be prevented by leaching thermochemically-treated tailings in 0.6M HNO3 solution. The best extraction efficiencies were achieved for aluminium (ca. 60%) and calcium (ca. 80%). 35% iron and 32% silicon were also extracted, alongside chromium (27%) and magnesium (25%). Thermochemical treatment using ammonium sulphate may therefore represent a promising technology for extracting valuable elements from PGM tailings, which could be subsequently converted to value-added products. However, it is not element-selective, and major elements were found to compete with the reagent to form water-soluble sulphate-metal species. Further development of this integrated process, which aims at achieving the full potential of utilisation of PGM tailings, is currently underway. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mesophilic and thermophilic anaerobic digestion of sulphate-containing wastewaters.

Science.gov (United States)

Colleran, E; Pender, S

2002-01-01

The effect of sulphate at an influent chemical oxygen demand (COD):sulphate ratio of 4 on the operational performance of anaerobic hybrid reactors treating molasses wastewater was investigated under mesophilic and thermophilic conditions in a long-term laboratory-scale study over a 1,081 day period. The presence of sulphate reduced the COD removal efficiency under both mesophilic and thermophilic conditions. At 55 degrees C, effluent acetate levels were consistently greater than 4000 mg l(-1) indicating that thermophilic acetate-utilising methane-producing bacteria (MPB) or sulphate-reducing bacteria (SRB) had not developed in the reactor under the conditions applied. At 37 degrees C, acetate was exclusively utilised by acetoclastic methanogens, whereas H2-utilising SRB predominated over H2-utilising MPB in the competition for hydrogen. By contrast, hydrogenotrophic MPB were shown to outcompete H2-utilising SRB during long-term thermophilic operation. 16SrDNA analysis of the seed sludge and reactor biomass on conclusion of the 37 degrees C and 55 degrees C trials illustrated that the dominant methanogen present on conclusion of the thermophilic trial in the absence of influent sulphate was related to Methanocorpusculum parvuum, and was capable of growth on both acetate and hydrogen. By contrast, an organism closely related to Methanobacterium thermoautotrophicum was the dominant methanogen present in the sulphate-fed reactor on completion of the thermophilic trial.

Challenges in LCA modelling of multiple loops for aluminium cans

DEFF Research Database (Denmark)

Niero, Monia; Olsen, Stig Irving

considered the case of closed-loop recycling for aluminium cans, where body and lid are different alloys, and discussed the abovementioned challenge. The Life Cycle Inventory (LCI) modelling of aluminium processes is traditionally based on a pure aluminium flow, therefore neglecting the presence of alloying...... elements. We included the effect of alloying elements on the LCA modelling of aluminium can recycling. First, we performed a mass balance of the main alloying elements (Mn, Fe, Si, Cu) in aluminium can recycling at increasing levels of recycling rate. The analysis distinguished between different aluminium...... packaging scrap sources (i.e. used beverage can and mixed aluminium packaging) to understand the limiting factors for multiple loop aluminium can recycling. Secondly, we performed a comparative LCA of aluminium can production and recycling in multiple loops considering the two aluminium packaging scrap...

Durability of bare and anodised aluminium in atmosphere of very different corrosivities I. Bare aluminium

International Nuclear Information System (INIS)

Gonzalez, J. A.; Escudero, E.; Lopez, V.; Simancas, J.; Morcillo, M.

2004-01-01

The behaviour of bare aluminium is studied in atmospheric exposure at 11 natural testing stations with salinity levels ranging between 2.1 and 684 mg Cl''- m''-2 d''-1. In atmospheres of low or moderate aggressivity aluminium behaves as a passive material, though the insignificant corrosion that is produced is sufficient to spoil its appearance. In contrast, at salinity levels of 50 mg Cl''- m''-2 ''-1 or above, aluminium is susceptible to pitting corrosion even in the first year of atmospheric exposure, or in the second year at salinities of ≤ 10 mg Cl''- m''-2 d''-1. For comparative purposes, results are included for aluminium protected with an anodic film of 28 μm thickness exposed at the same testing stations. A 28 μm anodic film, correctly sealed, prevents the risk of localised corrosion even in the most unfavourable situations. (Author) 23 refs

Are high rates of sulphate reduction associated with anaerobic oxidation of methane

Energy Technology Data Exchange (ETDEWEB)

Devol, A H; Ahmed, S I

1981-01-01

Classical models of sulphur diagenesis in marine sediments are based on the assumption that the rate of sulphate reduction is first order with respect to oxidizable particulate organic carbon (POC). This assumption requires that oxidizable POC, sulphate concentration and the sulphate reduction rate be highest at the top of the sulphate reduction zone and decrease exponentially with increasing sediment depth. However, to explain recent observations of concave upwards methane distributions, the anaerobic consumption of methane has been proposed. Furthermore, it has been proposed that this consumption takes place near the bottom of the sulphate reducing zone where sulphate concentrations are low. Thus, if sulphate reducing bacteria are associated with the anaerobic oxidation of methane, a peak in sulphate reduction rate might be expected in this deep consumption zone. The importance of the process in sedimentary sulphur diagenesis is indicated by calculations estimating that 30 to 75% of the downward sulphate flux at depth may be consumed by methane oxidation within this zone. We present here profiles of sulphate reduction rate in anoxic sediments that show distinct local maxima at the depth where the anaerobic oxidation of methane would be expected. Our measurements were made during July and August 1978 in Saanich Inlet, an anoxic fjord located on the south-east of Vancouver Island, British Columbia. The inlet has a shallow sill (approx 70 m) which restricts circulation of the deeper water (maximum depth 225 m) inside the basin to the extent that for about 8 months of the year the bottom waters contain hydrogen sulphide, the inlet is an ideal location for studying sedimentary sulphate reduction because reactions with oxygen and the effects of burrowing organisms can be neglected.

Fatigue test on aluminium bridges

NARCIS (Netherlands)

Maljaars, J.; Soetens, F.; Straalen, van IJ.J.

2005-01-01

Traffic bridges are subjected to variable loads and should therefore be checked on fatigue. Especially low weight materials, like aluminium, are sensitive to fatigue, because the variable load is a substantial part of the total load. This paper shows the structural design of an aluminium bridge

Fatal aluminium phosphide poisoning

Directory of Open Access Journals (Sweden)

Meena Mahesh Chand

2015-06-01

Full Text Available Aluminium phosphide (AlP is a cheap solid fumigant and a highly toxic pesticide which is commonly used for grain preservation. AlP has currently aroused interest with a rising number of cases in the past four decades due to increased use for agricultural and non-agricultural purposes. Its easy availability in the markets has increased also its misuse for committing suicide. Phosphine inhibits cellular oxygen utilization and can induce lipid peroxidation. Poisoning with AlP has often occurred in attempts to commit suicide, and that more often in adults than in teenagers. This is a case of suicidal consumption of aluminium phosphide by a 32-year-old young medical anesthetist. Toxicological analyses detected aluminium phosphide. We believe that free access of celphos tablets in grain markets should be prohibited by law.

Friction Welding of Aluminium and Aluminium Alloys with Steel

Directory of Open Access Journals (Sweden)

Andrzej Ambroziak

2014-01-01

Full Text Available The paper presents our actual knowledge and experience in joining dissimilar materials with the use of friction welding method. The joints of aluminium and aluminium alloys with the different types of steel were studied. The structural effects occurring during the welding process were described. The mechanical properties using, for example, (i microhardness measurements, (ii tensile tests, (iii bending tests, and (iv shearing tests were determined. In order to obtain high-quality joints the influence of different configurations of the process such as (i changing the geometry of bonding surface, (ii using the interlayer, or (iii heat treatment was analyzed. Finally, the issues related to the selection of optimal parameters of friction welding process were also investigated.

Aluminium cables in automotive applications : Prestudy of aluminium cable uses in Scania products&Failure analysis and evaluation

OpenAIRE

Man, Yu

2016-01-01

The increasing demand of light constructed vehicles as well as soaring price of copper metal owing to limited nature resources have been promoting the use of aluminium metal as an alternative conductor of automotive cables. This thesis work is to lay theoretical foundations for further research and development regarding the introduction of new automotive cables i.e. aluminium cables. Current application of automotive aluminium cables in automotive industry as well as failure analysis and eval...

Application of radioactivation analysis for determination of impurities in aluminium, raw materials and in samples from aluminium production process

International Nuclear Information System (INIS)

Vucina, L.J.

1977-01-01

Trace elements in aluminium, raw materials and in the samples from different stages of aluminium production were determined by nondestructive neutron radioactivation analysis. The samples were taken from the Bayer's process of alumina production (bauxite, red sludge and alumina), from the components of the reduction cell (anode, criolyte and AlF 3 ) and of the final product - aluminium (purity 99.5-99.7%). Under given set of conditions ten trace elements (V,La,Ga,Mn,Co,Cr,Sc,Sb,Zn and Fe) were determined in aluminium and followed through the production process. It was found that the main impurities in aluminium are iron (0.15%) and zinc (0.O6%). It has been concluded that the purity of produced aluminium depends mainly on the purity of used alumina. The second important source of contamination of aluminium is anode. The results obtained by radioactivation analysis for V, Mn, Cr and Fe fall within the ranges of concentrations of these elements determined by use of other methods (volumetry, spectrophotometry, atomic absorption). Higher values for zinc were obtained by radioactivation analysis, probably due to unsatisfactory irradiation and measuring conditions for this element. The possibilities of application of radioactivation analysis to these kinds of samples are also disscused

Aluminium in allergen-specific subcutaneous immunotherapy--a German perspective.

Science.gov (United States)

Kramer, Matthias F; Heath, Matthew D

2014-07-16

We are living in an "aluminium age" with increasing bioavailability of the metal for approximately 125 years, contributing significantly to the aluminium body burden of humans. Over the course of life, aluminium accumulates and is stored predominantly in the lungs, bones, liver, kidneys and brain. The toxicity of aluminium in humans is briefly summarised, highlighting links and possible causal relationships between a high aluminium body burden and a number of neurological disorders and disease states. Aluminium salts have been used as depot-adjuvants successfully in essential prophylactic vaccinations for almost 100 years, with a convincing positive benefit-risk assessment which remains unchanged. However, allergen-specific immunotherapy commonly consists of administering a long-course programme of subcutaneous injections using preparations of relevant allergens. Regulatory authorities currently set aluminium limits for vaccines per dose, rather than per treatment course. Unlike prophylactic vaccinations, numerous injections with higher proportions of aluminium-adjuvant per injection are applied in subcutaneous immunotherapy (SCIT) and will significantly contribute to a higher cumulative life dose of aluminium. While the human body may cope robustly with a daily aluminium overload from the environment, regulatory cumulative threshold values in immunotherapy need further addressing. Based on the current literature, predisposing an individual to an unusually high level of aluminium, such as through subcutaneous immunotherapy, has the potential to form focal accumulations in the body with the propensity to exert forms of toxicity. Particularly in relation to longer-term health effects, the safety of aluminium adjuvants in immunotherapy remains unchallenged by health authorities - evoking the need for more consideration, guidance, and transparency on what is known and not known about its safety in long-course therapy and what measures can be taken to prevent or

Study of the process of multistage leaching of alum shale's sulphate d ashes

International Nuclear Information System (INIS)

Maremae, E.; Ruendal, L.; Ahelik, V.

1991-01-01

The scheme of the process was worked out on the basis of small (the weight of starting ashes 1 kg) and big (76.2 kg) laboratory tests with the result of getting aluminium potassium sulphate (alum) as a commercial product, and a technological solution with increased content of metals (Ti, Mo, V, U, etc.). Ashes received by means of Toolse deposit (Estonia) alum-shale fluidized-bed ashing at 800 o C, were used as basic material. The ashes were sulphate d in combustion tubes provided with electric heater using sulphate roasting process: the ashes were mixed with 75% H 2 SO 4 with the ratio S : L = 4 : 3 to get a homogeneous paste which was calcinated in the tube at 250-300 o C for 30 min. The calcinated paste (clinker) was treated with boiling water. The leaching experiments were carried out with various S : L ratios; in small test - in 2-litre bulbs, equipped with a stirring-rod, reflux condenser and thermometer, in the pulp at boiling temperature (101 o C). The hot leaching pulp was filtered under pressure using forcing filters. The final solutions were cooled and treated in order to receive alum. Under the conditions of a discontinuous process, the yield of raw alum (content of Fe 2 O 3 ∼1%) made up 240-270 kg/t of the starting ashes, both at the expense of the ashes' own potassium and at the expense of the potassium added from outside. The standard alum with regard to the content of iron admixture was obtained after repeated recrystallization of the raw alum. After the separation of alum, the solutions with the specific weight of 1.4-1.5 t/m 3 , and with the following average metal and sulphuric acid content in the solutions of the small and big tests were obtained: Ti 4.8 and 8.3; Mo 0.4 and 0.8; V 1.0 and 1.9; U 0.2 and 0.5; Fe 66 and 90; Al 18 and 20; K 1.9 and 3.4; H 2 SO 4 117 and 123 g/l, respectively. The extraction of metals into the solution in small and big tests was as follows: ti 71 and 64, Mo 73 and 66, V94 and 86, U 91 and 77, Fe 69 and 60, Al 45

Spark counting technique with an aluminium oxide film

International Nuclear Information System (INIS)

Kawai, H.; Koga, T.; Morishima, H.; Niwa, T.; Nishiwaki, Y.

1980-01-01

Automatic spark counting of etch-pits on a polycarbonate film produced by nuclear fission fragments is now used for neutron monitoring in several countries. A method was developed using an aluminium oxide film instead of a polycarbonate as the neutron detector. Aluminium oxide films were prepared as follows: A cleaned aluminium plate as an anode and a nickel plate as a cathode were immersed in dilute sulfuric acid solution and electric current flowed between the electrodes at 12degC for 10-30 minutes. Electric current density was about 10 mA/cm 2 . The aluminium plate was then kept in boiling water for 10-30 minutes for sealing. The thickness of the aluminium oxide layer formed was about 1μm. The aluminium plate attached to a plate of suitable fissionable material, such as uranium or thorium, was irradiated with neutrons and set in a usual spark counter for fission track counting. One electrode was the aluminium plate and the other was an aluminized polyester sheet. Sparked pulses were counted with a usual scaler. The advantage of using spark counting with an aluminium oxide film for neutron monitoring is rapid measurement of neutron exposure, since chemical etching which is indispensable for spark counting with a polycarbonate detector film, is not needed. (H.K.)

Removal of radium from aqueous sulphate solutions

International Nuclear Information System (INIS)

Weir, D.R.; Masters, J.T.; Neven, M.

1983-01-01

Radium is often present in ores and an aqueous solution associated with the ore may consequently contain dissolved radium. It is frequently necessary to remove radium from such solutions to reduce the total radium content to a prescribed low level before the solution can be returned to the environment. The present invention is based on the discovery that the total radium content can be reduced to a satisfactory level within a reasonable time by adding a soluble barium salt to a radium-containing sulphate solution which also contains dissolved magnesium at a pH not greater than about 0 to precipitate radium as barium radium sulphate, raising the pH to at least 11 to precipitate an insoluble magnesium compound which collects the barium radium sulphate precipitate, and separating substantially all of the precipitates from the solution

Computerised analysis of sulphate action on model concrete piles

Digital Repository Service at National Institute of Oceanography (India)

Deshmukh, A.M.; Balasubramanian, S.; Venugopal, C.

Sulphate action severely affects the durability of marine structures. It is imperative to study precisely the effects of magnesium sulphate on pile foundations in the marine environment. In the present paper an attempt is made to assess and analyse...

Steam generated conversion coating on aluminium alloys

DEFF Research Database (Denmark)

Din, Rameez Ud; Jellesen, Morten Stendahl; Ambat, Rajan

Aluminium and its alloys are widely used in aerospace industry owing to their high strength to weight ratio. The surface of aluminium under normal conditions has a thin oxide film (2.5-10 nm) responsible for its inherent corrosion resistance. This oxide film can further be converted or transformed...... into functional conversion coatings in order to enhance corrosion resistance and adhesion to paint systems. Chromium based conversion coatings have been extensively used on aluminium alloys to improve adhesion of subsequent paint layers and corrosion resistance. However, the use of hexavalent chromium is strictly...... regulated due to its toxic nature and suspected carcinogenicity. So, it is highly imperative to develop other alternatives for chrome conversion coatings. Treatment of aluminium with natural water at elevated temperatures results in the formation of different forms of aluminium oxide (γ-AlO(OH) , Al(OH)3...

Persistent Skin Reactions and Aluminium Hypersensitivity Induced by Childhood Vaccines

DEFF Research Database (Denmark)

Salik, Elaha; Løvik, Ida; Andersen, Klaus E

2016-01-01

There is increasing awareness of reactions to vaccination that include persistent skin reactions. We present here a retrospective investigation of long-lasting skin reactions and aluminium hypersensitivity in children, based on medical records and questionnaires sent to the parents. In the 10-year...... period 2003 to 2013 we identified 47 children with persistent skin reactions caused by childhood vaccinations. Most patients had a typical presentation of persisting pruritic subcutaneous nodules. Five children had a complex diagnostic process involving paediatricians, orthopaedics and plastic surgeons...... treated with potent topical corticosteroids and disappeared slowly. Although we advised families to continue vaccination of their children, one-third of parents omitted or postponed further vaccinations....

Advances in development and application of aluminium batteries

DEFF Research Database (Denmark)

Qingfeng, Li; Zhuxian, Qiu

2001-01-01

Aluminium has long attracted attention as a potential battery anode because of its high theoretical voltage and specific energy. The protective oxide layer at aluminium surface is however detrimental to its performance to achieve its reversible potential, and also causing the delayed activation o...... aluminium batteres, especially aluminium-air batteries, and a wide range of their applications from emergency power supplies, reserve batteries field portable batteries, to batteries for electric vehicles and underwater propulsion....

Alveolar proteinosis associated with aluminium dust inhalation.

Science.gov (United States)

Chew, R; Nigam, S; Sivakumaran, P

2016-08-01

Secondary alveolar proteinosis is a rare lung disease which may be triggered by a variety of inhaled particles. The diagnosis is made by detection of anti-granulocyte-macrophage colony-stimulating factor antibodies in bronchoalveolar lavage fluid, which appears milky white and contains lamellar bodies. Aluminium has been suggested as a possible cause, but there is little evidence in the literature to support this assertion. We report the case of a 46-year-old former boilermaker and boat builder who developed secondary alveolar proteinosis following sustained heavy aluminium exposure. The presence of aluminium was confirmed both by histological examination and metallurgical analysis of a mediastinal lymph node. Despite cessation of exposure to aluminium and treatment with whole-lung lavage which normally results in improvements in both symptoms and lung function, the outcome was poor and novel therapies are now being used for this patient. It may be that the natural history in aluminium-related alveolar proteinosis is different, with the metal playing a mediating role in the disease process. Our case further supports the link between aluminium and secondary alveolar proteinosis and highlights the need for measures to prevent excessive aluminium inhalation in relevant industries. © The Author 2016. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Bacterial sulphate reduction and the development of alkalinity. II. Laboratory experiments with soils

Energy Technology Data Exchange (ETDEWEB)

Abd-El-Malek, Y; Rizk, S G

1963-01-01

In waterlogged soils sulphate reduction was characterized by increases in counts of sulphate reducers, and increase in titratable alkalinity, insoluble carbonate, and soluble sulphides, and a decrease in soluble Ca/sup 2 +/ + Mg/sup 2 +/. Presence of organic matter greatly enhanced sulphate reduction. A linear relationship between the amount of sulphate reduced and increases in titratable alkalinity and insoluble carbonate were apparent. The potential effects of sulphate reduction on soil fertility through the development of alkalinity are discussed.

Safety and efficacy of Bolus administration of magnesium sulphate ...

African Journals Online (AJOL)

Safety and efficacy of Bolus administration of magnesium sulphate for preeclampsia. ... On-going research is addressing its administration in terms of dosage, duration and safety. Objective: We evaluated a ... Keywords: safety, efficacy, bolus magnesium sulphate, preeclampsia, University of Benin Teaching Hospital

Kinetics and mechanism of protection of thymine from sulphate ...

Indian Academy of Sciences (India)

Unknown

The rate constant of sulphate radical anion with caffeic acid has been ... transfer of radical sites from base moiety to sugar moiety. Strand ... titrated with a standard ceric ammonium sulphate solution as reported by Kapoor et al.7. At room ...

Bacterial sulphate reduction and the development of alkalinity. I. Experiments with synthetic media

Energy Technology Data Exchange (ETDEWEB)

Abd-El-Malek, Y; Rizk, S G

1963-01-01

In liquid cultures of desulphovibrio desulphuricans the effects of the following on sulphate reduction were determined: The type of cation (ca++ or na+) attached to the sulphate ion; the presence of calcium carbonate alone and with sodium chloride; the concentration of sodium sulphate, sodium lactate and sodium chloride; and the initial pH. The titratable alkalinity formed as a result of sulphate reduction was found to be quantitatively related to the sulphate reduced, and apparently unaffected by strain variation or energy source.

Ion beam analysis of aluminium in thin layers

International Nuclear Information System (INIS)

Healy, M.J.F.; Pidduck, A.J.; Dollinger, G.; Gorgens, L.; Bergmaier, A.

2002-01-01

This work quantifies aluminium in thin surface and near surface layers. In one example, the layer overlies a thin gallium nitride layer on an aluminium oxide substrate and in a second example the aluminium exists just below the surface of an indium arsenide substrate. The technique of non-Rutherford elastic backscattering of protons was used for the samples where aluminum in the layer of interest needed to be resolved from aluminium in the sapphire substrate and the results were corroborated at the Technische Universitaet Muenchen using heavy ion elastic recoil detection analysis. In the second example, where it was unnecessary to isolate the signal of aluminium in the layer of interest (as the substrate contained no aluminium), then the 27 Al(d,p 01 ) 28 Al nuclear reaction was used. The elastic proton scattering cross section of aluminum was found to vary very rapidly over the energy range of interest

The aluminium content of infant formulas remains too high.

Science.gov (United States)

Chuchu, Nancy; Patel, Bhavini; Sebastian, Blaise; Exley, Christopher

2013-10-08

Recent research published in this journal highlighted the issue of the high content of aluminium in infant formulas. The expectation was that the findings would serve as a catalyst for manufacturers to address a significant problem of these, often necessary, components of infant nutrition. It is critically important that parents and other users have confidence in the safety of infant formulas and that they have reliable information to use in choosing a product with a lower content of aluminium. Herein, we have significantly extended the scope of the previous research and the aluminium content of 30 of the most widely available and often used infant formulas has been measured. Both ready-to-drink milks and milk powders were subjected to microwave digestion in the presence of 15.8 M HNO3 and 30% w/v H2O2 and the aluminium content of the digests was measured by TH GFAAS. Both ready-to-drink milks and milk powders were contaminated with aluminium. The concentration of aluminium across all milk products ranged from ca 100 to 430 μg/L. The concentration of aluminium in two soya-based milk products was 656 and 756 μg/L. The intake of aluminium from non-soya-based infant formulas varied from ca 100 to 300 μg per day. For soya-based milks it could be as high as 700 μg per day. All 30 infant formulas were contaminated with aluminium. There was no clear evidence that subsequent to the problem of aluminium being highlighted in a previous publication in this journal that contamination had been addressed and reduced. It is the opinion of the authors that regulatory and other non-voluntary methods are now required to reduce the aluminium content of infant formulas and thereby protect infants from chronic exposure to dietary aluminium.

Preparation of aluminium lakes by electrocoagulation

OpenAIRE

Prapai Pradabkham

2008-01-01

Aluminium lakes have been prepared by electrocoagulation employing aluminium as electrodes. The electrocoagulation is conducted in an aqueous alcoholic solution and is completed within one hour. The dye content in the lake ranges approximately between 4-32%.

Sulphation reactions of oxidic dust particles in waste heat boiler environment. Literature review

Energy Technology Data Exchange (ETDEWEB)

Ranki, T.

1999-09-01

Sulphation of metal oxides has an important role in many industrial processes. In different applications sulphation reactions have different aims and characteristics. In the flash smelting process sulphation of oxidic flue dust is a spontaneous and inevitable phenomena, which takes place in the waste heat boiler (WHB) when cooling down hot dust laden off-gases from sulphide smelters. Oxidic dust particles (size 0 - 50 {mu}m) react with O{sub 2} and SO{sub 2} or SO{sub 3} in a certain temperature range (500 - 800 deg C). Sulphation reactions are highly exothermic releasing large amount of heat, which affects the gas cooling and thermal performance of the boiler. Thermodynamics and kinetics of the system have to be known to improve the process and WHB operation. The rate of sulphation is affected by the prevailing conditions (temperature, gas composition) and particle size and microstructure (porosity, surface area). Some metal oxides (CuO) can react readily with SO{sub 2} and O{sub 2} and act as self-catalysts, but others (NiO) require the presence of an external catalyst to enhance the SO{sub 3} formation and sulphation to proceed. Some oxides (NiO) sulphate directly, some (CuO) may form first intermediate phases (basic sulphates) depending on the reaction conditions. Thus, the reaction mechanisms are very complex. The aim of this report was to search information about the factors affecting the dust sulphation reactions and suggested reaction mechanisms and kinetics. Many investigators have studied sulphation thermodynamics and reaction kinetics and mechanisms of macroscopical metal oxide pieces, but only few articles have been published about sulphation of microscopical particles, like dust. All the found microscale studies dealt with sulphation reactions of calcium oxide, which is not present in the flash smelting process, but used as an SO{sub 2} absorbent in the combustion processes. However, also these investigations may give some hints about the sulphation

Thermal decomposition of uranyl sulphate hydrate

International Nuclear Information System (INIS)

Sato, T.; Ozawa, F.; Ikoma, S.

1980-01-01

The thermal decomposition of uranyl sulphate hydrate (UO 2 SO 4 .3H 2 O) has been investigated by thermogravimetry, differential thermal analysis, X-ray diffraction and infrared spectrophotometry. As a result, it is concluded that uranyl sulphate hydrate decomposes thermally: UO 2 SO 4 .3H 2 O → UO 2 SO 4 .xH 2 O(2.5 = 2 SO 4 . 2H 2 O → UO 2 SO 4 .H 2 O → UO 2 SO 4 → α-UO 2 SO 4 → β-UO 2 SO 4 → U 3 O 8 . (author)

Thermometric titration of sulphate.

Science.gov (United States)

Williams, M B; Janata, J

1970-06-01

Direct thermometric titration of sulphate with a solution of barium perchlorate is proposed. The stoichiometry of the titration is shown to be critically dependent on the concentration of ethanol in the titration medium. The titration is rapid and suffers from only a few interferences.

Serum aluminium levels of workers in the bauxite mines.

Science.gov (United States)

de Kom, J F; Dissels, H M; van der Voet, G B; de Wolff, F A

1997-01-01

Aluminium is produced from the mineral bauxite. Occupational exposure is reported during the industrial processing of aluminium and is associated with pulmonary and neurotoxicity. However, data on exposure and toxicity of workers in the open bauxite mining industry do not exist. Therefore, a study was performed to explore aluminium exposure in employees involved in this bauxite mining process in a Surinam mine. A group of workers occupationally exposed to aluminium in an open bauxite mine were compared with a group of nonexposed wood processors. Serum aluminium was analyzed using atomic absorption spectrometry Data from the clinical chemistry of the blood and a questionnaire were used to explore determinants for aluminium exposure. No significant difference between serum aluminium in the exposed (4.4 +/- 2.0 micrograms/L, n = 27) and control group (5.1 +/- 1.5 micrograms/L, n = 27) was detected. For the serum concentration of the clinical chemical variables (calcium, citrate, and creatinine), a statistically significant difference was computed (p < or = 0.02) between the exposed and control group. All levels were slightly higher in the exposed group; no statistically significant correlations with serum aluminium were found. In this study, serum aluminium values were in the normal range, no significant difference between the groups could be detected despite long-term occupational exposure.

Magnesium sulphate for fetal neuroprotection

DEFF Research Database (Denmark)

Bickford, Celeste D; Magee, Laura A; Mitton, Craig

2013-01-01

of cerebral palsy (CP) averted and quality-adjusted life years (QALYs). RESULTS: From a health system and a societal perspective, respectively, a savings of $2,242 and $112,602 is obtained for each QALY gained and a savings of $30,942 and $1,554,198 is obtained for each case of CP averted when magnesium......BACKGROUND: The aim of this study was to assess the cost-effectiveness of administering magnesium sulphate to patients in whom preterm birth at ... sensitivity analyses were used to compare the administration of magnesium sulphate with the alternative of no treatment. Two separate cost perspectives were utilized in this series of analyses: a health system and a societal perspective. In addition, two separate measures of effectiveness were utilized: cases...

Argon-arc welding of heat resisting aluminium alloys

International Nuclear Information System (INIS)

Ryazantsev, V.I.; Fedoseev, V.A.

1997-01-01

Welding of aluminium heat resisting alloys of the Al-Cu-Mg system is studied. The hot-shortness of heat-resistant alloys M40, 1150 and 1151 are at the level of aluminium alloys 1201 and by 2-3 times lower as compared to the aluminium alloy AMg6. The M40, 1150 and 1151 alloys have unquestionable advantages against other know aluminium alloys only at temperatures of welded structures operation, beginning with 150-2000 deg C and especially at 250 deg C

Sulphate, more than a nutrient, protects the microalga Chlamydomonas moewusii from cadmium toxicity

Energy Technology Data Exchange (ETDEWEB)

Mera, Roi; Torres, Enrique, E-mail: torres@udc.es; Abalde, Julio

2014-03-01

Highlights: • Sulphate effect on cadmium toxicity in the microalga Chlamydomonas moewusii Gerloff. • Cadmium increases the sulphur requirements in Chlamydomonas moewusii. • Kinetic coefficients for sulphate utilization and cadmium effect on them. • Sulphate and cadmium influence on the biosynthesis of low-molecular mass thiols. • Cadmium toxicity reduction by sulphate due to higher biosynthesis of thiols. - Abstract: Sulphur is an essential macroelement that plays important roles in living organisms. The thiol rich sulphur compounds, such as cysteine, γ-Glu–Cys, glutathione and phytochelatins participate in the tolerance mechanisms against cadmium toxicity. Plants, algae, yeasts and most prokaryotes cover their demand for reduced sulphur by reduction of inorganic sulphate. The aim of this study was to investigate, using a bifactorial experimental design, the effect of different sulphate concentrations in the nutrient solution on cadmium toxicity in the freshwater microalga Chlamydomonas moewusii. Cell growth, kinetic parameters of sulphate utilization and intracellular concentrations of low-molecular mass thiol compounds were determined. A mathematical model to describe the growth of this microalga based on the effects of sulphate and cadmium was obtained. An ANOVA revealed an interaction between them, 16% of the effect sizes was explained by this interaction. A higher amount of sulphate in the culture medium allowed a higher cadmium tolerance due to an increase in the thiol compound biosynthesis. The amount of low-molecular mass thiol compounds, mainly phytochelatins, synthesized by this microalga was significantly dependent on the sulphate and cadmium concentrations; the higher phytochelatin content was obtained in cultures with 4 mg Cd/L and 1 mM sulphate. The maximum EC{sub 50} value (based on nominal cadmium concentration) reached for this microalga was 4.46 ± 0.42 mg Cd/L when the sulphate concentration added to the culture medium was also 1 m

Net shape powder processing of aluminium

International Nuclear Information System (INIS)

Schaffer, G.B.

2000-01-01

The increasing interest in light weight materials coupled to the need for cost-effective processing have combined to create a significant opportunity for aluminium powder metallurgy. Net shape processing of aluminium using the classical press-and-sinter powder metallurgy technique is a unique and important metal-forming method which is cost effective in producing complex parts at, or very close to, final dimensions. This paper provides an overview of the net shape powder processing of aluminium. Current research is critically reviewed and the future potential is briefly considered

Relationship between sulphate and sulphur dioxide in the air

Energy Technology Data Exchange (ETDEWEB)

Fugas, M; Gentilizza, M

1978-01-01

The relationship between the sulphate in suspended particulates and sulphur dioxide in the air was studied in various urban and industrial areas. The relationship is best described by the equation y = ax/sup b/, where y is the percentage of the sulphate S in the total S (sulphate and sulphur dioxide) and x is the concentration of the total S in the air. The regression coefficients a and b seem to be characteristics of the area. In urban areas studied so far a was between 316 and 378 and b between -0.74 and -0.83. In industrial areas polluted by dust which contains elevated concentrations of metals a was between 91 and 107 and b between -0.35 and -0.49. In the area polluted by cement dust there was practically no correlation between the sulphate S (%) and the total S, but a relatively high correlation between absolute amounts of the sulphate S and the total S. The relations indicate that the limitation of SO/sub 2/ conversion is influenced by aerosol composition. Aerosols containing certain metals may promote the conversion by a catalytic effect while alkaline substances by increasing the pH. Whether this can only happen in the plume or in the air as well remains to be clarified.

Acid sulphate soil disturbance and metals in groundwater: Implications for human exposure through home grown produce

International Nuclear Information System (INIS)

Hinwood, Andrea Lee; Horwitz, Pierre; Appleyard, Steve; Barton, Caroline; Wajrak, Magda

2006-01-01

A significant emerging environmental problem is the disturbance and oxidation of soils with high levels of iron sulphide minerals resulting in acidification and causing the mobilization of metals into groundwater. This process is occurring in many parts of the world. In Western Australia, impacted groundwater is extracted by residents for domestic use. We sought to establish domestic use patterns of bore water and the concentration of metals. Sixty-seven domestic bore water samples clearly indicated oxidation of sulphidic materials with heavy metal concentrations ranging for aluminium (< DL-37.0 mg/L), arsenic (< DL-6.6 mg/L), iron (< DL-1200 mg/L), cadmium (< DL-0.021 mg/L), lead (< DL-0.040 mg/L), selenium (< DL-0.006 mg/L). A high proportion of residents used bore water on home grown produce. The study suggests that there is potential for human exposure to heavy metals via the consumption of home grown produce. This warrants further investigation in light of increasing acid sulphate soil disturbance in many locations. - Acidified bore water may introduce metals into produce for home consumption

Preparation of aluminium lakes by electrocoagulation

Directory of Open Access Journals (Sweden)

Prapai Pradabkham

2008-07-01

Full Text Available Aluminium lakes have been prepared by electrocoagulation employing aluminium as electrodes. The electrocoagulation is conducted in an aqueous alcoholic solution and is completed within one hour. The dye content in the lake ranges approximately between 4-32%.

Investigation of aluminium state in some popular food, which are cooked in aluminium vessels, using spectroscopic analysis methods

International Nuclear Information System (INIS)

Al-Shahneh, M.; Saheune, Kh.

2009-01-01

Aluminium and lead elements were determined in drinking water and salt solution from chick-pea and faba-bean cooked in aluminium vessels and others from teflon for comparison using atomic absorption spectroscopy by graphite furnace. The relationship between heating time and aluminium quantities transferred to these food solutions was investigated. The lead element was determined taking into consideration the fact that this element may enter in these vessels somehow during the manufacturing process. Results show that the highest value of aluminium quantities was recorded in salt solution ( 17.022 μg/ml) without heating , followed by chick-pea solution (9.95 μg/ml), then faba-bean solution (2.81 μg/ml) when the heated period was 120 minutes. (author)

Effect of tempering on corrosion resistance of cast aluminium bronzes

International Nuclear Information System (INIS)

Aaltonen, P.; Klemetti, K.; Haenninen, H.

1985-01-01

The subject of this study is corrosion resistance of aluminium bronzes, which are copper base alloys containing aluminium up to 12% with additions of nickel, iron and manganese. The main conclutions that can be drawn are: (1) The dealloying corrosion resistance of nickel-aluminium bronze is much better than that of aluminium bronze with iron and manganese additions, but it is not immune; (2) The dealloying corrosion resistance of aluminium bronzes can be improved by appropiate heat treatments. The best properties were obtained by temperering between 600 and 800 deg C, depending on the initial microstructure; (3) In crevice conditions, where local acidification can occur, dealloying of aluminium bronzes is a consequence of the preferential attack of aluminium-rich phases. By appropriate tempering, a uniform distribution of aluminium-rich phases is obtained and the continous path for selective corrosion is not formed

Feasibility of lead removal from industrial effluents by sulphate reducing bacteria

International Nuclear Information System (INIS)

Nunez, L. A.; Diez, M.; Rodriguez, F. J.

2009-01-01

Battery manufacturing wastewater contains high concentration of sulphate and lead at low pH values. Biogical treatment by anaerobic reduction of sulphate to sulphite, with organic matter as electron donor, increases alkalinity and allow precipitating lead as sulphide. the type of organic matter, COD/SO 4 ratio and lead concentration over sulphate reduction rate are investigated in this work. (Author)

Differential responses of freshwater wetland soils to sulphate pollution

NARCIS (Netherlands)

Lamers, L.P.M.; Dolle, ten G.E.; Berg, van den S.T.G.; Delft, van S.P.J.; Roelofs, J.G.M.

2001-01-01

Sulphate (SO42-) reduction rates are generally low in freshwater wetlands and are regulated by the scarce availability of the ion. Increased concentrations of this electron acceptor due to sulphur (S) pollution of groundwater and surface water may, however, lead to high sulphate reduction rates now

What is the risk of aluminium as a neurotoxin?

Science.gov (United States)

Exley, Christopher

2014-06-01

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

The effect of magnesium on partial sulphate removal from mine water as gypsum.

Science.gov (United States)

Tolonen, Emma-Tuulia; Rämö, Jaakko; Lassi, Ulla

2015-08-15

The aim of this research was to investigate the effect of magnesium on the removal efficiency of sulphate as gypsum from mine water. The precipitation conditions were simulated with MINEQL + software and the simulation results were compared with the results from laboratory jar test experiments. Both the simulation and the laboratory results showed that magnesium in the mine water was maintaining sulphate in a soluble form as magnesium sulphate (MgSO4) at pH 9.6. Thus magnesium was preventing the removal of sulphate as gypsum (CaSO4·2H2O). However, change in the lime precipitation pH from 9.6 to 12.5 resulted in magnesium hydroxide (Mg(OH)2) precipitation and improved sulphate removal. Additionally, magnesium hydroxide could act as seed crystals for gypsum precipitation or co-precipitate sulphate further enhancing the removal of sulphate from mine water. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sulphated glycosaminoglycans and proteoglycans in the developing vertebral column of juvenile Atlantic salmon (Salmo salar)

OpenAIRE

Hannesson, Kirsten O.; Ytteborg, Elisabeth; Takle, Harald; Enersen, Grethe; B?verfjord, Grete; Pedersen, Mona E.

2015-01-01

In the present study, the distribution of sulphated glycosaminoglycans (GAGs) in the developing vertebral column of Atlantic salmon (Salmo salar) at 700, 900, 1100 and 1400?d? was examined by light microscopy. The mineralization pattern was outlined by Alizarin red S and soft structures by Alcian blue. The temporal and spatial distribution patterns of different types of GAGs: chondroitin-4-sulphate/dermatan sulphate, chondroitin-6-sulphate, chondroitin-0-sulphate and keratan sulphate were add...

Detection of aluminium in different culinary media using black ...

African Journals Online (AJOL)

Jacques Blessing

The interactions between food and aluminium local kitchen utensils can be a potential source of aluminium released which can ... need to be adopted to preserve consumers' health. ..... Corrosion behaviour of different ... Aluminium beverage.

Microwave assisted synthesis of nano sized sulphate doped hydroxyapatite

International Nuclear Information System (INIS)

Alshemary, Ammar Z.; Goh, Yi-Fan; Akram, Muhammad; Razali, Ili Rabihah; Abdul Kadir, Mohammed Rafiq; Hussain, Rafaqat

2013-01-01

Highlights: ► Phase pure nano-sized sulphur doped hydroxyapatite has been synthesized. ► TEM analysis confirmed formation of needle shaped structure. ► Lattice parameters and cell volume increased with increase in sulphate doping. ► Crystallite size decreased as sulphate content inside the structure increased. ► Degree of crystallinity decreased with increase in sulphate substitution. - Abstract: Inorganic sulphate is required by all mammalian cells to function properly, it is the fourth most abundant anion in the human plasma. Sulphate ions are the major source of sulphur which is considered an important element for sustenance of life as it is present in the essential amino and is required by cells to function properly. In this study we have successfully substituted sulphate ions (SO 4 2− ) into hydroxyapatite (Ca 10 (PO 4 ) 6−x (SO 4 ) x (OH) 2−x ) lattice via ion exchange process with phosphate group. Concentration of SO 4 2− ions was varied between X = 0.05–0.5, using (Ca (NO 3 ) 2 ·4H 2 O), ((NH 4 ) 2 HPO 4 ) and (Na 2 SO 4 ) as starting materials. X-ray diffraction (XRD), Fourier transform IR spectroscopy (FTIR), showed that the substitution of SO 4 2− ions into the lattice resulted in peak broadening and reduced peak height due to the amorphous nature and reduced crystallinity of the resulting HA powder. Transmission electron microscopy (TEM) and field emission electron microscopy (FESEM) analysis confirmed the formation of needle shaped particles of 41 nm size with homogenous and uniform distribution of element within the HA structure

There is (still too much aluminium in infant formulas

Directory of Open Access Journals (Sweden)

Burrell Shelle-Ann M

2010-08-01

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

Molybdenum solubility in aluminium nitrate solutions

Energy Technology Data Exchange (ETDEWEB)

Heres, X.; Sans, D.; Bertrand, M.; Eysseric, C. [CEA, Centre de Marcoule, Nuclear Energy Division, DRCP, BP 17171, 30207 Bagnols-sur-Ceze Cedex (France); Brackx, E.; Domenger, R.; Excoffier, E. [CEA, Centre de Marcoule, Nuclear Energy Division, DTEC, BP 17171, 30207 Bagnols-sur-Ceze Cedex (France); Valery, J.F. [AREVA-NC, DOR/RDP, Paris - La Defense (France)

2016-07-01

For over 60 years, research reactors (RR or RTR for research testing reactors) have been used as neutron sources for research, radioisotope production ({sup 99}Mo/{sup 99m}Tc), nuclear medicine, materials characterization, etc... Currently, over 240 of these reactors are in operation in 56 countries. They are simpler than power reactors and operate at lower temperature (cooled to below 100 C. degrees). The fuel assemblies are typically plates or cylinders of uranium alloy and aluminium (U-Al) coated with pure aluminium. These fuels can be processed in AREVA La Hague plant after batch dissolution in concentrated nitric acid and mixing with UOX fuel streams. The aim of this study is to accurately measure the solubility of molybdenum in nitric acid solution containing high concentrations of aluminium. The higher the molybdenum solubility is, the more flexible reprocessing operations are, especially when the spent fuels contain high amounts of molybdenum. To be most representative of the dissolution process, uranium-molybdenum alloy and molybdenum metal powder were dissolved in solutions of aluminium nitrate at the nominal dissolution temperature. The experiments showed complete dissolution of metallic elements after 30 minutes long stirring, even if molybdenum metal was added in excess. After an induction period, a slow precipitation of molybdic acid occurs for about 15 hours. The data obtained show the molybdenum solubility decreases with increasing aluminium concentration. The solubility law follows an exponential relation around 40 g/L of aluminium with a high determination coefficient. Molybdenum solubility is not impacted by the presence of gadolinium, or by an increasing concentration of uranium. (authors)

Weight-of-evidence approach in assessment of ecotoxicological risks of acid sulphate soils in the Baltic Sea river estuaries

Energy Technology Data Exchange (ETDEWEB)

Wallin, Jaana, E-mail: jaana.wallin@jyu.fi [Finnish Environment Institute SYKE, Survontie 9 A, FI-40500 Jyväskylä (Finland); Karjalainen, Anna K. [Finnish Environment Institute SYKE, Survontie 9 A, FI-40500 Jyväskylä (Finland); Schultz, Eija [Finnish Environment Institute SYKE, Hakuninmaantie 6, FI-00430 Helsinki (Finland); Järvistö, Johanna; Leppänen, Matti; Vuori, Kari-Matti [Finnish Environment Institute SYKE, Survontie 9 A, FI-40500 Jyväskylä (Finland)

2015-03-01

Acidity and leaching of metals from acid sulphate soils (ASSs) impair the water quality of receiving surface waters. The largest ASS areas in Europe are found in the coasts of the northern Baltic Sea. We used weight-of-evidence (WoE) approach to assess potential risks in 14 estuary sites affected by ASS in the Gulf of Finland, northern Baltic Sea. The assessment was based on exposure and effect profiles utilizing sediment and water metal concentrations and concurrent pH variation, sediment toxicity tests using the luminescent bacterium Vibrio fischeri and the midge Chironomus riparius, and the ecological status of benthic macroinvertebrate communities. Sediment metal concentrations were compared to national sediment quality criteria/guidelines, and water metal concentrations to environmental quality standards (EQSs). Hazard quotients (HQs) were established for maximum aluminium, cadmium and zinc concentrations at low pH based on applicable US EPA toxicity database. Sediment metal concentrations were clearly elevated in most of the studied estuaries. The EQS of cadmium (0.1 μg/l) was exceeded in 3 estuaries out of 14. The pH-minima were below the national threshold value (5.5) between good and satisfactory water quality in 10 estuaries. V. fischeri bioluminescence indicated toxicity of the sediments but toxic response was not observed in the C. riparius emergence test. Benthic invertebrate communities were deteriorated in 6 out of 14 sites based on the benthic invertebrate quality index. The overall ecotoxicological risk was assessed as low in five, moderate in three and high in five of the estuary sites. The risk assessment utilizing the WoE approach indicated that harmful effects of ASSs are likely to occur in the Baltic Sea river estuaries located at the ASS hotspot area. - Highlights: • Acid sulphate soils release high amounts of metals and acidity. • Metals and acidity are transported to estuary sites. • Acid sulphate soils impair the ecological status

Niobium-base grain refiner for aluminium

International Nuclear Information System (INIS)

Silva Pontes, P. da; Robert, M.H.; Cupini, N.L.

1980-01-01

A new chemical grain refiner for aluminium has been developed, using inoculation of a niobium-base compound. When a bath of molten aluminium is inoculated whith this refiner, an intermetallic aluminium-niobium compound is formed which acts as a powerful nucleant, producing extremely fine structure comparable to those obtained by means of the traditional grain refiner based on titanium and boron. It was found that the refinement of the structure depends upon the weight percentage of the new refiner inoculated as well as the time of holding the bath after inoculation and before pouring, but mainly on the inoculating temperature. (Author) [pt

Sulphate removal from uraniferous liquors

International Nuclear Information System (INIS)

Berger, B.

1983-01-01

A process for the recovery of uranium from liquor resulting from the attack of sulphur containing uraniferous ores by an alkaline solution of sodium carbonate and/or sodium bicarbonate is claimed. An ion exchange resin is used to separate the uranium from the solution of sodium carbonate and/or bicarbonate and sodium sulphate. The ion exchange resin is then eluted with a solution of ammonium carbonate and/or bicarbonate to provide an eluate containing ammonium uranyl tricarbonate, ammonium carbonate and/or bicarbonate and ammonium sulphate. The eluate is heated to boiling to convert the ammonium uranyl tricarbonate to ammonium uranate and/or diuranate. Ammonia, carbon dioxide and water vapor are released. The precipitated ammonium uranate and/or diuranate is separated from the remaining liquor and calcined to give uranium trioxide

IEC 61267: Feasibility of type 1100 aluminium and a copper/aluminium combination for RQA beam qualities.

Science.gov (United States)

Leong, David L; Rainford, Louise; Zhao, Wei; Brennan, Patrick C

2016-01-01

In the course of performance acceptance testing, benchmarking or quality control of X-ray imaging systems, it is sometimes necessary to harden the X-ray beam spectrum. IEC 61267 specifies materials and methods to accomplish beam hardening and, unfortunately, requires the use of 99.9% pure aluminium (Alloy 1190) for the RQA beam quality, which is expensive and difficult to obtain. Less expensive and more readily available filters, such as Alloy 1100 (99.0% pure) aluminium and copper/aluminium combinations, have been used clinically to produce RQA series without rigorous scientific investigation to support their use. In this paper, simulation and experimental methods are developed to determine the differences in beam quality using Alloy 1190 and Alloy 1100. Additional simulation investigated copper/aluminium combinations to produce RQA5 and outputs from this simulation are verified with laboratory tests using different filter samples. The results of the study demonstrate that although Alloy 1100 produces a harder beam spectrum compared to Alloy 1190, it is a reasonable substitute. A combination filter of 0.5 mm copper and 2 mm aluminium produced a spectrum closer to that of Alloy 1190 than Alloy 1100 with the added benefits of lower exposures and lower batch variability. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Remediation of phosphate-contaminated water by electrocoagulation with aluminium, aluminium alloy and mild steel anodes.

Science.gov (United States)

Vasudevan, Subramanyan; Lakshmi, Jothinathan; Jayaraj, Jeganathan; Sozhan, Ganapathy

2009-05-30

The present study provides an electrocoagulation process for the remediation of phosphate-contaminated water using aluminium, aluminium alloy and mild steel as the anodes and stainless steel as the cathode. The various parameters like effect of anode materials, effect of pH, concentration of phosphate, current density, temperature and co-existing ions, and so forth, and the adsorption capacity was evaluated using both Freundlich and Langmuir isotherm models. The adsorption of phosphate preferably fitting the Langmuir adsorption isotherm suggests monolayer coverage of adsorbed molecules. The results showed that the maximum removal efficiency of 99% was achieved with aluminium alloy anode at a current density of 0.2 A dm(-2), at a pH of 7.0. The adsorption process follows second-order kinetics.

Serum and urinary oestrone sulphate in pregnancy and delivery measured by a direct radioimmunoassay

International Nuclear Information System (INIS)

Honjo, Hideo; Kitawaki, Jo; Itoh, Masafumi; Yasuda, Jinsuke; Yamamoto, Takara; Yamamoto, Takao; Okada, Hiroji; Ohkubo, Tadashi; Nambara, Toshio

1986-01-01

Serum and urinary levels of oestrone sulphate in pregnancy and delivery were measured by a direct radioimmunoassay without hydrolysis. the serum and urinary oestrone sulphate increased as pregnancy progressed. the mean level of serum oestrone sulphate increased to the highest peak of 494 pmol/ml at the 35th gestational week and then decreased. The mean level of urinary oestrone sulphate increased to the highest peak of 1.28 μmol/l at the 34th gestational week and the decreased. At vaginal deliveries, the mean level of maternal peripheral serum oestrone sulphate increased hourly at as high a level as 979 pmol/ml. The mean serum level of oestrone sulphate was 204 pmol/ml in the umbilical artery and 145 pmol/ml in the umbilical vein. At Caesarean section, on the other hand, the maternal peripheral serum level of oestrone sulphate averaged 362 pmol/ml. The mean serum levels of oestrone sulphate wre 90.7 pmol/ml and 171 pmol/ml in the umbilical artery and umbilical vein, respectively. These results suggest a maternal origin of oestrone sulphate in pregnancy, with fluctuations in the levels being of interest in relation to labour pain. (author)

Human biomonitoring of aluminium after a single, controlled manual metal arc inert gas welding process of an aluminium-containing worksheet in nonwelders.

Science.gov (United States)

Bertram, Jens; Brand, Peter; Hartmann, Laura; Schettgen, Thomas; Kossack, Veronika; Lenz, Klaus; Purrio, Ellwyn; Reisgen, Uwe; Kraus, Thomas

2015-10-01

Several existing field studies evaluate aluminium welding works but no thoroughly controlled exposure scenario for welding fume has been described yet. This study provides information about the uptake and elimination of aluminium from welding fumes under controlled conditions. In the Aachen Workplace Simulation Laboratory, we are able to generate welding fumes of a defined particle mass concentration. We exposed 12, until then occupationally unexposed participants with aluminium-containing welding fumes of a metal inert gas (MIG) welding process of a total dust mass concentration of 2.5 mg/m(3) for 6 h. Room air filter samples were collected, and the aluminium concentration in air derived. Urine and plasma samples were collected directly before and after the 6-h lasting exposure, as well as after 1 and 7 days. Human biomonitoring methods were used to determine the aluminium content of the samples with high-resolution continuum source atomic absorption spectrometry. Urinary aluminium concentrations showed significant changes after exposure compared to preexposure levels (mean t(1) (0 h) 13.5 µg/L; mean t(2) (6 h) 23.5 µg/L). Plasma results showed the same pattern but pre-post comparison did not reach significance. We were able to detect a significant increase of the internal aluminium burden of a single MIG aluminium welding process in urine, while plasma failed significance. Biphasic elimination kinetic can be observed. The German BAT of 60 µg/g creatinine was not exceeded, and urinary aluminium returned nearly to baseline concentrations after 7 days.

Multiply-negatively charged aluminium clusters and fullerenes

Energy Technology Data Exchange (ETDEWEB)

Walsh, Noelle

2008-07-15

Multiply negatively charged aluminium clusters and fullerenes were generated in a Penning trap using the 'electron-bath' technique. Aluminium monoanions were generated using a laser vaporisation source. After this, two-, three- and four-times negatively charged aluminium clusters were generated for the first time. This research marks the first observation of tetra-anionic metal clusters in the gas phase. Additionally, doubly-negatively charged fullerenes were generated. The smallest fullerene dianion observed contained 70 atoms. (orig.)

Irradiation of aluminium alloy materials with electron beam

International Nuclear Information System (INIS)

Konno, Osamu; Masumoto, Kazuyoshi

1982-01-01

It is a theme with a room for discussion to employ the stainless steel composed of longer half-life materials for the vacuum system of accelerators, from the viewpoint of radiation exposure. Therefore, it is desirable to use aluminium of shorter half-life in place of stainless steel. As a result of investigation on the above theme in the 1.2 GeV electron linac project in Tohoku University, it has been concluded that aluminium alloy vacuum chambers can reduce exposure dose by about one or two figures as compared with stainless steel ones. Of course, aluminium alloy contains trace amounts of Mg, Si, Ti, Cr, Mn, Fe, Zn, Cu and others. Therefore, four kinds of aluminium alloy considered to be usable have been examined for induced radioactivity by electron beam irradiation. Stainless steel SUS 304 has been also irradiated for comparison. Radiation energy has been 30 MeV and 200 MeV. When stainless steel and aluminium alloy were compared, aluminium alloy was very effective for reducing surface dose in low energy irradiation. In 200 MeV irradiation, the dose ratio of aluminium alloy to stainless steel became 1/30 to 1/100 after one week, though the dose difference between these two materials became smaller in 100 days or more after irradiation. If practical inspection and repair are implemented during the period from a few days to one week after shutdown, the aluminium alloy is preferable for exposure dose reduction even in high energy irradiation. (Wakatsuki, Y.)

Introduction. Aluminium production on electrolytic cells with calcined anodes

International Nuclear Information System (INIS)

Galushkin, N.V.

1995-01-01

This chapter presents the monograph content, which includes the description of physicochemical processes in aluminium electrolytic cells, and mechanism of electrolytic aluminium obtaining. The short description of aluminium electrolytic cells construction is presented in this book as well.

Aluminium allergy and granulomas induced by vaccinations for children

DEFF Research Database (Denmark)

Andersen, Rosa Marie O; Zachariae, Claus; Johansen, Jeanne Duus

2014-01-01

Vaccination with aluminium-adsorbed vaccines can induce aluminium allergy with persistent itching subcutaneous nodules at the injection site - vaccination granulomas. In this article we give an overview of childhood aluminium-adsorbed vaccines available in Denmark. Through literature studies we...

Synthesis and properties of bimetallic aluminium alkoxides

International Nuclear Information System (INIS)

Vyshinskaya, K.I.; Vasil'ev, G.A.; Vishnyakova, T.A.

1997-01-01

A single stage method of aluminium bimetallic alkoxide synthesis, which consists in activated aluminium reaction with metal salts in the relevant alcohols, has been developed. Properties of the compounds prepared are described

Beryllium electrodeposition on aluminium cathode from chloride melts

International Nuclear Information System (INIS)

Nichkov, I.F.; Novikov, E.A.; Serebryakov, G.A.; Kanashin, Yu.P.; Sardyko, G.N.

1980-01-01

Cathodic processes during beryllium deposition on liquid and solid aluminium cathodes are investigated. Mixture of sodium, potassium and beryllium chloride melts served as an lectrolyte. Beryllium ion discharge at the expense of alloy formation takes place at more positive potentials than on an indifferent cathode at low current densities ( in the case of liquid aluminium cathode). Metallographic analysis and measurements of microhardness have shown, that the cathodic product includes two phases: beryllium solid solution in aluminium and metallic beryllium. It is concluded, that aluminium-beryllium alloys with high cathodic yield by current can be obtained by the electrolytic method

Investigation process of alcoholysis of hydride aluminium-adobe

International Nuclear Information System (INIS)

Numanov, M.I.; Normatov, I.Sh.; Mirsaidov, U.M.

2001-01-01

Considering of that process of acid treatment of aluminium-adobe hydride realizes in the ethyl alcohol media it was necessary study the process of alcoholysis of AlH 3 and aluminium additives. In the end of article authors became to conclusion that deficiency of spontaneous alcoholysis of AlH 3 in adobe caused by protective action of fiber; solvate ability of LiCl and alkoxy aluminium hydride of lithium-LiCl·CO 2 H 5 OH, Li Al(OC 2 H 5 ) 4 ·nC 2 H 5 OH decreasing the expectancy of responding of alcohol with aluminium hydride

KS R41B. A high performance steel-aluminium composite material; KS R41B. Ein Stahl-Aluminium-Verbundwerkstoff fuer hohe Belastungen

Energy Technology Data Exchange (ETDEWEB)

Deicke, K. [KS Gleitlager GmbH (Germany). Bereich Metall; Matucha, H.; Schubert, W. [KS Gleitlager GmbH, St. Leon-Rot (Germany); Steffens, T. [KS Gleitlager GmbH, Neckarsulm (Germany)

2002-08-01

Aluminium-tin alloys have been well-known for a long time and have proved to be suitable bearing materials for crankshaft bearings for many years. The known alloy AlZn4,5SiCuPb is one of the aluminium materials capable of sustaining the highest mechanical loads. In order to achieve optimum sliding properties, it would be necessary to increase the share of the soft lead phase in the alloy. This article by KS Gleitlager GmbH shows a reasonably priced manufacturing technology for high-performance aluminium-zinc-silicon-copper alloys. (orig.) [German] Die Aluminium-Zinn-Lagerlegierungen sind seit langem bekannt und haben sich seit Jahren als Lagerwerkstoff fuer Kurbelwellenlager bewaehrt. Die Legierung AlZn4,5SiCuPb gehoert zu den mechanisch am hoechsten belastbaren Aluminium-Werkstoffen. Um optimale Gleiteigenschaften zu erzielen, muesste in der Legierung der Anteil des weichen Bleis noch weiter erhoeht werden. Dieser Beitrag der KS Gleitlager GmbH zeigt eine kostenguenstige Herstelltechnologie fuer hochbelastbare Aluminium-Zink-Silizium-Kupfer-Legierungen. (orig.)

Energy Absorption of Monolithic and Fibre Reinforced Aluminium Cylinders

NARCIS (Netherlands)

De Kanter, J.L.C.G.

2006-01-01

Summary accompanying the thesis: Energy Absorption of Monolithic and Fibre Reinforced Aluminium Cylinders by Jens de Kanter This thesis presents the investigation of the crush behaviour of both monolithic aluminium cylinders and externally fibre reinforced aluminium cylinders. The research is based

The hypobranchial mucin of the whelk Buccinum undatum L. The polysaccharide sulphate component.

Science.gov (United States)

Hunt, S; Jevons, F R

1966-02-01

1. A polysaccharide sulphate has been isolated from the hypobranchial mucin of the whelk Buccinum undatum. 2. The molecular weight of this polysaccharide, which is a glucan carrying one ester sulphate group per monosaccharide residue, is 1.7x10(5). 3. Some investigations bearing on the location of the ester sulphate groups are reported. 4. The viscosity of the whole mucin has been shown to depend mainly on the glucan sulphate.

Microwave assisted synthesis of nano sized sulphate doped hydroxyapatite

Energy Technology Data Exchange (ETDEWEB)

Alshemary, Ammar Z.; Goh, Yi-Fan; Akram, Muhammad; Razali, Ili Rabihah [Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor Darul Ta’zim (Malaysia); Abdul Kadir, Mohammed Rafiq [Medical Implant Technology Group, Faculty of Biomedical Engineering and Health Science, Universiti Teknologi Malaysia,81310 UTM Skudai, Johor Darul Ta’zim (Malaysia); Hussain, Rafaqat, E-mail: rafaqat@kimia.fs.utm.my [Ibnu Sina Institute for Fundamental Science Studies, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor DarulTa’zim (Malaysia)

2013-06-01

Highlights: ► Phase pure nano-sized sulphur doped hydroxyapatite has been synthesized. ► TEM analysis confirmed formation of needle shaped structure. ► Lattice parameters and cell volume increased with increase in sulphate doping. ► Crystallite size decreased as sulphate content inside the structure increased. ► Degree of crystallinity decreased with increase in sulphate substitution. - Abstract: Inorganic sulphate is required by all mammalian cells to function properly, it is the fourth most abundant anion in the human plasma. Sulphate ions are the major source of sulphur which is considered an important element for sustenance of life as it is present in the essential amino and is required by cells to function properly. In this study we have successfully substituted sulphate ions (SO{sub 4}{sup 2−}) into hydroxyapatite (Ca{sub 10}(PO{sub 4}){sub 6−x}(SO{sub 4}){sub x}(OH){sub 2−x}) lattice via ion exchange process with phosphate group. Concentration of SO{sub 4}{sup 2−} ions was varied between X = 0.05–0.5, using (Ca (NO{sub 3}){sub 2}·4H{sub 2}O), ((NH{sub 4}){sub 2}HPO{sub 4}) and (Na{sub 2}SO{sub 4}) as starting materials. X-ray diffraction (XRD), Fourier transform IR spectroscopy (FTIR), showed that the substitution of SO{sub 4}{sup 2−} ions into the lattice resulted in peak broadening and reduced peak height due to the amorphous nature and reduced crystallinity of the resulting HA powder. Transmission electron microscopy (TEM) and field emission electron microscopy (FESEM) analysis confirmed the formation of needle shaped particles of 41 nm size with homogenous and uniform distribution of element within the HA structure.

Characteristics and antioxidant of Ulva intestinalis sulphated polysaccharides extracted with different solvents.

Science.gov (United States)

Peasura, Napassorn; Laohakunjit, Natta; Kerdchoechuen, Orapin; Wanlapa, Sorada

2015-11-01

Ulva intestinalis, a tubular green seaweed, is a rich source of nutrient, especially sulphated polysaccharides. Sulphated polysaccharides from U. intestinalis were extracted with distilled water, 0.1N HCl, and 0.1N NaOH at 80°C for 1, 3, 6, 12, and 24h to study the effect of the extraction solvent and time on their chemical composition and antioxidant activity. Different types of solvents and extraction time had a significant influence on the chemical characteristics and antioxidant activity (pMonosaccharide composition and FT-IR spectra analyses revealed that sulphated polysaccharides from all solvent extractions have a typical sugar backbone (glucose, rhamnose, and sulphate attached at C-2 or C-3 of rhamnose). Sulphated polysaccharides extracted with acid exhibited greater antioxidant activity than did those extracted with distilled water and alkali. The results indicated that solvent extraction could be an efficacious method for enhancing antioxidant activity by distinct molecular weight and chemical characteristic of sulphated polysaccharides. Copyright © 2015 Elsevier B.V. All rights reserved.

Corrosion of aluminium in copper-aluminium couples under a marine environment: Influence of polyaniline deposited onto copper

International Nuclear Information System (INIS)

Vera, Rosa; Verdugo, Patricia; Orellana, Marco; Munoz, Eduardo

2010-01-01

Research highlights: → The presence of Polyaniline in the Al-Cu system produces a decrease in the oxygen reduction reaction. → In the marine enviroment, aluminium in Al-Cu couples, suffers pitting and exfoliation. → The aluminium deterioration increases with chloride and enviromental sulphur dioxide presence, mainly when it is united to bare copper. - Abstract: In this study, we examined how aluminium corrosion in Al-Cu/PANI galvanic couples in a marine environment is influenced by deposition of polyaniline (PANI) on copper. Polarization curves and immersion assays in 0.1 M NaCl were performed. The morphologies of etched Al and corrosion products were observed by SEM, and the Al ions in solution were quantified by atomic absorption spectroscopy. A reduction in aluminium damage due to galvanic corrosion was observed as a result of decreased effective area for the oxygen reduction reaction on Cu/PANI electrode. Furthermore, an electrochemical reduction of PANI from leucoemeraldine to emeraldine base is proposed.

Aluminium hydroxide-the carrier for catalysts coating

International Nuclear Information System (INIS)

Normatov, I.Sh.; Mirsaidov, U.M.

2003-01-01

At present time several methods of receiving aluminium hydroxide are exist. But all they differ by much staging of process connected with preliminary receiving of intermediate compounds, with application of expensive metallic aluminium

Effects of aluminium surface morphology and chemical modification on wettability

DEFF Research Database (Denmark)

Rahimi, Maral; Fojan, Peter; Gurevich, Leonid

2014-01-01

-life aluminium surfaces of different morphology: unpolished aluminium, polished aluminium, and aluminium foil, were subjected to surface modification procedures which involved the formation of a layer of hydrophilic hyperbranched polyethyleneglycol via in situ polymerization, molecular vapour deposition...... of a monolayer of fluorinated silane, and a combination of those. The effect of these surface modification techniques on roughness and wettability of the aluminium surfaces was elucidated by ellipsometry, contact angle measurements and atomic force microscopy. We demonstrated that by employing different types...

Quantitation and identification of methanogens and sulphate reducers in Olkiluoto groundwater

International Nuclear Information System (INIS)

Bomberg, M.; Nyyssoenen, M.; Itaevaara, M.

2010-08-01

The GEOFUNC Project focuses on the microbiology connected to safety and risk assessment of the final disposal of high radioactive nuclear waste. Methanogenic archaea and sulphate reducing bacteria are significant groups of microorganisms in anaerobic environments, and are of crucial concern for the safe long term storage of nuclear waste in deep bedrock. The sulphate reducing bacteria are able to produce sulphide which may cause corrosion of the copper in the radioactive waste storage capsules. Methanogens, on the other hand, may produce quantities of methane from various organic carbon compounds, CO 2 and H 2 . Methane may both serve as carbon source for methanotrophic microbial groups, and may also cause mobilization of radionuclides, as a result of gas discharge through fractures in the bedrock. The transition zones between the sulphate rich and methane rich waters are locations for microbial processes where the methane may serve as carbon source for sulphate reducing bacteria, which in turn would produce corrosive sulphides. It has been estimated that only 1-10 % of all the microorganisms present in the environment can be isolated and cultivated. Uncultured microorganisms can be identified and their numbers in the environment quantified by identification of specific marker genes that are essential for their functions by use of molecular methods. Methanogens, for example, can be identified by their genes for methyl coenzyme M reductase (mcrA), which is an essential enzyme involved in the production of methane. The mcrA is specifically present only in methanogenic archaea. Sulphate reducers are identified by their dissimilatory sulphite reductase genes (dsrB), which are present in and essential for all microorganisms performing dissimilatory sulphate reducing. In the GEOFUNC project, a quantitative PCR method (qPCR) was developed for the detection of methanogens and sulphate reducers. This method is based on specific quantitative detection of marker genes

Aluminium removal from water after defluoridation with the electrocoagulation process.

Science.gov (United States)

Sinha, Richa; Mathur, Sanjay; Brighu, Urmila

2015-01-01

Fluoride is the most electronegative element and has a strong affinity for aluminium. Owing to this fact, most of the techniques used for fluoride removal utilized aluminium compounds, which results in high concentrations of aluminium in treated water. In the present paper, a new approach is presented to meet the WHO guideline for residual aluminium concentration as 0.2 mg/L. In the present work, the electrocoagulation (EC) process was used for fluoride removal. It was found that aluminium content in water increases with an increase in the energy input. Therefore, experiments were optimized for a minimum energy input to achieve the target value (0.7 mg/L) of fluoride in resultant water. These optimized sets were used for further investigations of aluminium control. The experimental investigations revealed that use of bentonite clay as coagulant in clariflocculation brings down the aluminium concentration of water below the WHO guideline. Bentonite dose of 2 g/L was found to be the best for efficient removal of aluminium.

Irradiation effects in magnesium and aluminium alloys

International Nuclear Information System (INIS)

Sturcken, E.F.

1979-01-01

Effects of neutron irradiation on microstructure, mechanical properties and swelling of several magnesium and aluminium alloys were studied. The neutron fluences of 2-3 X 10 22 n/cm 2 , >0.2 MeV produced displacement doses of 20 to 45 displacements per atom (dpa). Ductility of the magnesium alloys was severely reduced by irradiation induced recrystallization and precipitation of various forms. Precipitation of transmuted silicon occurred in the aluminium alloys. However, the effect on ductility was much less than for the magnesium alloys. The magnesium and aluminium alloys had excellent resistance to swelling: The best magnesium alloy was Mg/3.0 wt% Al/0.19 wt% Ca; its density decreased by only 0.13%. The best aluminium alloy was 6063, with a density decrease of 0.22%. (Auth.)

Steam Initiated Surface Modification of Aluminium Alloys

DEFF Research Database (Denmark)

Din, Rameez Ud

The extensive demand of aluminium alloys in various industries such as in transportationis mainly due to the high strength to weight ratio, which could be translated into fuel economy and efficiency. Corrosion protection of aluminium alloys is an important aspect for all applications which includes...... the use of aluminium alloys in the painted form requiring a conversion coating to improve the adhesion. Chromate based conversion coating processes are extremely good for these purposes, however the carcinogenic and toxic nature of hexavalent chromium led to the search for more benign and eco......, crystalline nano-particles, role of steam-based treatment on adhesion of industrially applied powder coating, and investigations of a failed painted aluminium window profile due to defects in the extruded profile. Chapters 13 and 14 describe the overall discussion, conclusions and future work based...

Deformation features of aluminium in tensile tests

International Nuclear Information System (INIS)

Quadros, N.F. de.

1984-01-01

It is presented a method to analyse stress-strain curves. Plastic and elastic strains were studied. The strains were done by tensile tests in four types of materials: highly pure aluminium, pure aluminium, commercially pure aluminium and aluminium - uranium. The chemical compositions were obtained by spectroscopy analysis and neutron activation analysis. Tensile tests were carried out at three strain rates, at room temperature, 100,200, 300 and 400 0 C, with knives extensometer and strain-gages to studied the elastic strain region. A multiple spring model based on two springs model to analyse elastic strain caused by tests without extensometers, taking in account moduli of elasticity and, an interactive analysis system with graphic capability were developed. It was suggested a qualitative model to explain the quantized multielasticity of Bell. (M.C.K.) [pt

Long-term result of out-patient neodymium-doped yttrium aluminium garnet laser photocoagulation surgery for patients with epistaxis.

Science.gov (United States)

Zhang, J; Qiu, R; Wei, C

2016-01-01

To evaluate the long-term efficacy of out-patient neodymium-doped yttrium aluminium garnet laser photocoagulation surgery for patients with epistaxis. A retrospective clinical study was conducted. A total of 217 consecutive patients who presented with acute or recurrent epistaxis received neodymium-doped yttrium aluminium garnet laser photocoagulation treatment in an out-patient setting. At three years, 94 per cent of acute epistaxis patients versus 88 per cent of recurrent epistaxis patients reported no bleeding. The outcome scores at 12 weeks and 3 years after treatment showed no significant differences between the 2 groups (p = 0.207 and p = 0.186). However, there was a significant difference in outcome scores at four weeks after treatment (p = 0.034). The median (and mean ± standard deviation) pain levels experienced during the laser operation (performed in an office setting) were 4.0 (3.75 ± 2.09) in the acute epistaxis group and 4.0 (3.83 ± 2.01) in the recurrent epistaxis group. Neither group had any complications. Neodymium-doped yttrium aluminium garnet laser photocoagulation is desirable in the treatment of both acute and recurrent epistaxis, and has long-lasting efficacy.

Dielectric aluminium phosphate thin films. Couches minces dielectriques de phosphate d'aluminium

Energy Technology Data Exchange (ETDEWEB)

Daviero, S. (Lab. Physicochimie des Materiaux Solides, 34 - Montpellier (France)); Avinens, C. (Lab. Physicochimie des Materiaux Solides, 34 - Montpellier (France)); Ibanez, A. (Lab. Physicochimie des Materiaux Solides, 34 - Montpellier (France)); Giuntini, J.C. (Lab. Physicochimie des Materiaux Solides, 34 -Montpellier (France)); Philippot, E. (Lab. Physicochimie des Materiaux Solides, 34 - Montpellier (France))

1993-04-01

Aluminium phosphate thin films on silicium substrate have been carried out from tributylphosphate and aluminium acetylacetonate precursors in solution through the ''pyrosol'' process. It can be observed a large range of chemical analysis in terms of experimental conditions. These thin films have been characterized by X-ray diffraction and infrared spectrometry. Their electrical characteristics, defined from direct current and alternative current measurements, are quite different to those of the crystallized phosphate and can be explained by P-O and Al-O ''dangling bond'' existence. (orig.).

Rapidly solidified aluminium for optical applications

NARCIS (Netherlands)

Gubbels, G.P.H.; Venrooy, B.W.H. van; Bosch, A.J.; Senden, R.

2008-01-01

This paper present the results of a diamond turning study of a rapidly solidified aluminium 6061 alloy grade, known as RSA6061. It is shown that this small grain material can be diamond turned to smaller roughness values than standard AA6061 aluminium grades. Also, the results are nearly as good as

[Determination of aluminium in flour foods with photometric method].

Science.gov (United States)

Ma, Lan; Zhao, Xin; Zhou, Shuang; Yang, Dajin

2012-05-01

To establish a determination method for aluminium in flour foods with photometric method. After samples being treated with microwave digestion and wet digestion, aluminium in staple flour foods was determined by photometric method. There was a good linearity of the result in the range of 0.25 - 5.0 microg/ml aluminium, r = 0.9998; limit of detection (LOD) : 2.3 ng/ml; limit of quantitation (LOQ) : 7 ng/ml. This method of determining aluminium in flour foods is simple, rapid and reliable.

Dose-response testing with nickel sulphate using the TRUE test in nickel-sensitive individuals. Multiple nickel sulphate patch-test reactions do not cause an 'angry back'

DEFF Research Database (Denmark)

Andersen, Klaus Ejner; Lidén, C; Hansen, J

1993-01-01

The aim of this study was to employ the TRUE test assay to confirm the presence or absence of the 'angry back' phenomenon, i.e. that a strong positive patch-test reaction heightens adjacent patch-test response. In addition, we wished to establish the dose-response relationship for nickel sulphate...... back' phenomenon was not apparent in this study, as the spill-over effect was not statistically significant. Strong reactions to high concentrations of nickel sulphate did not enhance the response to adjacent lower concentrations of nickel sulphate....

Comparison of reactivity to a metallic disc and 2% aluminium salt in 366 children, and reproducibility over time for 241 young adults with childhood vaccine-related aluminium contact allergy.

Science.gov (United States)

Gente Lidholm, Anette; Inerot, Annica; Gillstedt, Martin; Bergfors, Elisabet; Trollfors, Birger

2018-07-01

An aluminium hydroxide-adsorbed pertussis toxoid vaccine was studied in 76 000 children in the 1990s in Gothenburg, Sweden. Long-lasting itchy subcutaneous nodules at the vaccination site were seen in 745 participants. Of 495 children with itchy nodules who were patch tested for aluminium allergy, 377 were positive. In 2007-2008, 241 of the positive children were retested. Only in one third were earlier positive results reproduced. To further describe patch test reactions to different aluminium compounds in children with vaccine-induced aluminium allergy. Positive patch test results for metallic aluminium (empty Finn Chamber) and aluminium chloride hexahydrate 2% petrolatum (pet.) were analysed in 366 children with vaccine-induced persistent itching nodules tested in 1998-2002. Of those, 241 were tested a second time (2007-2008), and the patch test results of the two aluminium preparations were analysed. Patch testing with aluminium chloride hexahydrate 2% pet. is a more sensitive way to diagnose aluminium contact allergy than patch testing with metallic aluminium. A general decrease in the strength of reactions to both aluminium preparations in 241 children tested twice was observed. Aluminium contact allergy can be diagnosed by patch testing without using metallic aluminium. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Corrosion Performance of Inconel 625 in High Sulphate Content

Science.gov (United States)

Ismail, Azzura

2016-05-01

Inconel 625 (UNS N06625) is a type of nickel-chromium-molybdenum alloy with excellent corrosion resistance in a wide range of corrosive media, being especially resistant to pitting and crevice corrosion. However, in aggressive environment, Inconel 625 will suffer corrosion attack like other metals. This research compared the corrosion performance of Inconel 625 when exposed to higher sulphate content compared to real seawater. The results reveal that Inconel 625 is excellent in resist the corrosion attack in seawater. However, at increasing temperature, the corrosion resistance of this metal decrease. The performance is same in seawater with high sulphate content at increasing temperature. It can be concluded that sulphate promote perforation on Inconel 625 and become aggressive agents that accelerate the corrosion attack.

Effects of acid deposition on Dutch forest ecosystems

NARCIS (Netherlands)

Vries, de W.; Leeters, E.E.J.M.; Hendriks, C.M.A.

1995-01-01

Effects of elevated sulphur and nitrogen deposition on the solution chemistry of Dutch forest soils are mainly manifested by increased aluminium concentrations, associated with increased concentrations of sulphate and nitrate. Critical aluminium/base cation ratios are often exceeded below 20 cm soil

Effect of smelt aluminium on mechanical properties of steels

International Nuclear Information System (INIS)

Ryabov, V.R.; Dykhno, I.S.; Deev, G.F.; Karikh, V.V.

1987-01-01

Effect of smelt aluminium on mechanical properties of armco-iron and 12 Kh18N10T steel is studied. It is stated that in smelt aluminium and aluminium alloy contact with armco-iron the sample ductility is decreased. Corrosion effect of smelt alluminium on (18Kh15N5AM3) steel in the form of reinforced wire in aluminium-steel KAS-1A composite material is investigted. It is stated in experiment that during smelt alluminium-steel contact interaction of heterogeneous phases takes place

Study of corrosion in aluminium using neutron radiography technique

International Nuclear Information System (INIS)

Islam, M.N.; Alam, M.K.; Saklayen, M.A.; Ahsan, M.H.; Islam, S.M.A.; Zaman, M.A.

2000-01-01

Neutron radiography technique has been adopted for detection of corrosion in aluminium by filling artificially made holes on aluminium slab with Al(OH) 3 . The contrast between the optical densities of corrosion products and aluminium slab was assessed from the densitometric measurements. Variation of optical density difference with sample thickness has also been studied. The results confirm that approximately 0.039 mm thick corrosion products having diameter 10 mm can easily be detected in 2 cm thick aluminium slab. The linear attenuation coefficient of Al(OH) 3 has been obtained as 0.9447. From the present investigation it is confirmed that film neutron radiography (NR) technique is helpful for investigation of Al(OH) 3 type corrosion product in aluminium. (author)

Effects of aluminium surface morphology and chemical modification on wettability

Energy Technology Data Exchange (ETDEWEB)

Rahimi, M., E-mail: mar@sbi.aau.dk [Department of Energy and Environment, Danish Building Research Institute, Aalborg University, A.C. Meyers Vænge 15, 2450 København SV (Denmark); Fojan, P.; Gurevich, L. [Department of Physics and Nanotechnology, Aalborg University, Skjernvej 4, DK-9220 Aalborg East (Denmark); Afshari, A. [Department of Energy and Environment, Danish Building Research Institute, Aalborg University, A.C. Meyers Vænge 15, 2450 København SV (Denmark)

2014-03-01

Highlights: • Successful surface modification procedures on aluminium samples were performed involving formation of the layer of hydrophilic hyperbranched polyethyleneglycol (PEG) via in situ polymerization, molecular vapour deposition of a monolayer of fluorinated silane, and a combination of those. • The groups of surfaces with hydrophobic behavior were found to follow the Wenzel model. • A transition from Cassie–Baxter's to Wenzel's regime was observed due to changing of the surface roughness upon mechanical polishing in aluminium samples. - Abstract: Aluminium alloys are some of the predominant metals in industrial applications such as production of heat exchangers, heat pumps. They have high heat conductivity coupled with a low specific weight. In cold working conditions, there is a risk of frost formation on the surface of aluminium in the presence of water vapour, which can lead to the deterioration of equipment performance. This work addresses the methods of surface modification of aluminium and their effect of the underlying surface morphology and wettability, which are the important parameters for frost formation. Three groups of real-life aluminium surfaces of different morphology: unpolished aluminium, polished aluminium, and aluminium foil, were subjected to surface modification procedures which involved the formation of a layer of hydrophilic hyperbranched polyethyleneglycol via in situ polymerization, molecular vapour deposition of a monolayer of fluorinated silane, and a combination of those. The effect of these surface modification techniques on roughness and wettability of the aluminium surfaces was elucidated by ellipsometry, contact angle measurements and atomic force microscopy. We demonstrated that by employing different types of surface modifications the contact angle of water droplets on aluminium samples can be varied from 12° to more than 120°. A crossover from Cassie–Baxter to Wenzel regime upon changing the surface

Spectrophotometric determination of aluminium in steel with xylenol orange

International Nuclear Information System (INIS)

Majeed, A.; Javed, N.; Khan, M.S.

1996-01-01

Spectrophotometric determination of Aluminium in steel based on colour reaction between Aluminium and xylenol orange has been carried out. Red coloured complex formed in weak acidic solution is measured for its absorbance at 550 nm. The various optimum experimental conditions for Aluminium xylenol orange (Al-Xo) complex have been studied. (author)

Study of the sulphate expansion phenomenon in concrete: behaviour of the cemented radioactive wastes containing sulphate

International Nuclear Information System (INIS)

Li, Guanshu

1994-01-01

Sulphate attack is one of the major degradation processes of concrete. It is especially important in storing cemented radioactive wastes containing sulphate. In this thesis, we have thoroughly investigated the degradation mechanisms of cemented radioactive wastes by sulphate. The CaO-Al 2 O 3 -SO 3 -H 2 O systems with and without alkalis are studied. For the system without alkalis, experimental results show that it is the formation of a secondary ettringite under external water supply by steric effect that causes the expansion. For the system with alkalis, the ettringite does not appear while a new mineral called 'U', a sodium-substituted AFm phase is detected. This phase is shown to be responsible for the expansion and destruction of the specimens. The conditions for the formation, the product of solubility and many means of its synthesis are discussed, and a complete list of the inter-reticular distances file is given. The behaviour of the different types of cemented wastes containing sulphate are then studied with a special focus on the U phase on entity which was heretofore very little understood. The following three hypothetical mechanisms of sulphate expansion are proposed: the formation of the secondary U phase, the transformation of the U phase to the ettringite and the topochemical hydration of thenardite into mirabilite. Experiments on a simplified system have demonstrated clearly that the formation of the secondary U phase can induce enormous expansion by steric effect, this justifying the first assumption. Simulation by the mass and volume balances is carried out thereafter and enables us to estimate the expansion induced by the formation of the secondary U phase in the cemented wastes. The second assumption is also well verified by a series of leaching tests in different solutions on mixtures containing the U phase. On the basis of the analysis of the specimens under leaching, it has been assumed that the expansion is associated with the

Wear behavior of carbon fiber/aluminium-composites during abrasive loading; Verschleissverhalten von Kohlenstoffaser/Aluminium-Verbunden unter abrasiver Beanspruchung

Energy Technology Data Exchange (ETDEWEB)

Wielage, B.; Dorner, A. [Technische Univ. Chemnitz (Germany). Lehrstuhl fuer Verbundwerkstoffe

1998-07-01

Abrasive wear resistance of aluminium is significantly improved by the reinforcement with a high volume percentage of carbon fibres. The wear of unreinforced aluminium after scratching by a diamond indenter can be described as pure microgrooving without any micro-chipping. After integration of 70 vol.-% carbon fibers the damage mechanism is considerably altered and a great amount of micro-chipping occurs. The abrasive wear is strongly influenced by the fiber orientation. The best wear resistance is observed when the fibers are orientated perpendicular to the wear surface. (orig.) [Deutsch] Die Verstaerkung von Aluminium mit einem hohen Volumengehalt endloser Kohlenstoffasern verbessert erkennbar dessen Resistenz gegenueber Abrasionsverschleiss. Der Verschleiss von unverstaerktem Aluminium infolge des Ritzens mit einem Diamantindenter erfolgt in Form von reinem Mikrofurchen ohne Spanbildung. Aufgrund der Integration von 70 Vol.-% Kohlenstoffasern wird eine erhebliche Zunahme des Schaedigungsmechanismus Mikrospanen festgestellt. Die Faserorientierung hat merklichen Einfluss auf die Sensibilitaet gegenueber Abrasion. Orientierung der anisotropen Kohlenstoffasern senkrecht zur Verschleissoberflaeche bedingt den geringsten Abrasionsverschleiss. (orig.)

The effect of water on the sulphation of limestone

Energy Technology Data Exchange (ETDEWEB)

Chunbo Wang; Lufei Jia; Yewen Tan; E.J. Anthony [North China Electric Power University, Baoding City (China). School of Energy and Power Engineering

2010-09-15

A series of tests was conducted in a thermogravimetric analyzer (TGA) to study the sulphation behaviour of limestone in the presence of water over the temperature range of 800-850{sup o}C. Four different Canadian limestones, all with a particle size range of 75-425 {mu}m, were sulphated using a synthetic flue gas with a composition of 15% CO{sub 2}, 3% O{sub 2}, 0% or 10% H{sub 2}O, 1750 ppm SO{sub 2} and the balance N{sub 2}. Water was shown to have a significant promotional effect on sulphation, especially in the diffusion-controlled stage. However, the effect of water during the kinetic-controlled stage appeared to be much less pronounced. Based on these results, it is proposed that the presence of water leads to the transient formation of Ca(OH){sub 2} as an intermediate, which in turn reacts with SO{sub 2} at a faster rate than CaO does. Alternatively stated, it appears that H{sub 2}O acts as catalyst for the sulphation reaction of CaO. 30 refs., 8 figs., 3 tabs.

The action of diazoxide and minoxidil sulphate on rat blood vessels: a comparison with cromakalim.

Science.gov (United States)

Newgreen, D. T.; Bray, K. M.; McHarg, A. D.; Weston, A. H.; Duty, S.; Brown, B. S.; Kay, P. B.; Edwards, G.; Longmore, J.; Southerton, J. S.

1990-01-01

1. The actions of diazoxide and minoxidil sulphate have been compared with those of cromakalim in rat aorta and portal vein. 2. Diazoxide and minoxidil sulphate hyperpolarized the rat portal vein in a similar manner to cromakalim. 3. Cromakalim, diazoxide and minoxidil sulphate increased 42K and 86Rb efflux from rat portal vein, although minoxidil sulphate had only a small effect on 86Rb efflux. 4. Cromakalim, diazoxide and minoxidil sulphate increased 42K efflux from rat aorta but only cromakalim and diazoxide increased 86Rb efflux from this tissue. 5. Glibenclamide inhibited the relaxant actions of cromakalim, diazoxide and minoxidil sulphate on rat aorta and the increase in 42K efflux produced by these agents in this tissue. 6. Diazoxide relaxed an 80 mM KCl-induced contraction of rat aorta, whilst cromakalim and minoxidil sulphate were without effect. 7. Cromakalim, diazoxide and minoxidil sulphate had no effect on cyclic AMP or cyclic GMP concentrations in rat aorta. 8. It is concluded that diazoxide and minoxidil sulphate like cromakalim exhibit K+ channel opening properties in vascular smooth muscle. Diazoxide exerts an additional inhibitory action not related to the production of cyclic AMP or cyclic GMP. The action of minoxidil sulphate may be primarily located at a K+ channel which is relatively impermeable to 86Rb. PMID:2167738

Study of ionic movements during anodic oxidation of nitrogen-implanted aluminium

International Nuclear Information System (INIS)

Terwagne, G.; Lucas, S.; Bodart, F.; Sorensen, G.; Jensen, H.

1990-01-01

In recent years there has been a considerable interest in synthesizing aluminium nitrides by ion implantation in order to modify the tribological properties of aluminium. The growth of an oxide layer by anodic process on these synthesized aluminium nitrides gives an interesting oxide-on-semiconductor material with surprising dynamic and decorative properties. During the anodic oxidation, ionic movements are involved in the near-surface region of the aluminium material; these ionic movements have been studied by Rutherford backscattering spectrometry (RBS) and nuclear reaction analysis (NRA) on thin aluminium foils (7000 A) preimplanted with nitrogen and post-oxidized in an ammonium pentaborate solution. The growth of the oxide layer is reduced when the aluminium is preimplanted with nitrogen: the speed of oxidation depends on the implantation conditions (energy and fluence). Moreover, the aluminium nitride can be dissolved when all metallic aluminium staying between the surface and the AlN are consumed by the anodic process. (orig.)

Steam Assisted Accelerated Growth of Oxide Layer on Aluminium Alloys

DEFF Research Database (Denmark)

Din, Rameez Ud; Yuksel, Serkan; Jellesen, Morten Stendahl

2013-01-01

Corrosion resistance of aluminium alloys is related to the composition and morphology of the oxide film on the surface of aluminium. In this paper we investigated the use of steam on the surface modification of aluminium to produce boehmite films. The study reveals a detailed investigation...... of the effect of vapour pressure, structure of intermetallic particles and thickness of boehmite films on the corrosion behaviour of aluminium alloys....

Corrosion behaviour of borated aluminium used as neutron absorber

Energy Technology Data Exchange (ETDEWEB)

Emmerich, R. [EaglePicher Technologies GmbH, Oehringen (Germany); Ensinger, W.; Enders, B. [Philipps-Univ. of Marburg, Dept. of Chemistry, Material Science Centre (Germany)

2004-07-01

The electrochemical behaviour of pure and borated aluminium was examined. Measurements were performed in two different electrolytes at 90 C containing different trace-amounts of chloride. For borated aluminium current transients, i.e. metastable depassivation events were found. It is suggested to attribute these transients to less stable passivation layers in comparison to pure aluminium.

Effects of Aluminium Sulfate on Cadmium Accumulation in Rice

International Nuclear Information System (INIS)

Khamvarn, Vararas; Boontanon, Narin; Prapagdee, Benjaphorn; Kumsopa, Acharaporn; Boonsirichai, Kanokporn

2011-06-01

Full text: Cadmium accumulation in Pathum Thani 1 and Suphan Buri 60 rice cultivars was investigated upon treatment with aluminium sulfate as a precipitant. Rice was grown hydroponically in a medium containing 4 ppm cadmium nitrate with or without 4 ppm aluminium sulfate. Root, stem with leaves and grain samples were collected and analyzed for cadmium content using atomic absorption spectroscopy and inductively coupled plasma atomic emission spectroscopy. Without the addition of aluminium sulfate, Pathum Thani 1 and Suphan Buri 60 accumulated 24.71∫ 3.14 ppm and 34.43 ∫ 4.51 ppm (dry weight of whole plant) of cadmium, respectively. With aluminium sulfate, cadmium accumulation increased to 40.66 ∫ 2.47 ppm and 62.94 ∫ 10.69 ppm, respectively. The addition of aluminium sulfate to the planting medium did not reduce cadmium accumulation but caused the rice to accumulate more cadmium especially in the shoots and grains. This observation might serve as the basis for future research on the management of agricultural areas that are contaminated with cadmium and aluminium

Volatilisation and oxidation of aluminium scraps fed into incineration furnaces

International Nuclear Information System (INIS)

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

2012-01-01

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

Electron Conditioning of Technical Aluminium Surfaces

Energy Technology Data Exchange (ETDEWEB)

Le Pimpec, F

2004-09-02

The effect of electron conditioning on commercially aluminium alloys 1100 and 6063 were investigated. Contrary to the assumption that electron conditioning, if performed long enough, can reduce and stabilize the SEY to low values (= 1.3, value of many pure elements [1]), the SEY of aluminium did not go lower than 1.8. In fact, it reincreases with continued electron exposure dose.

Magnesium sulphate and other anticonvulsants for women with pre-eclampsia.

Science.gov (United States)

Duley, Lelia; Gülmezoglu, A Metin; Henderson-Smart, David J; Chou, Doris

2010-11-10

Eclampsia, the occurrence of a seizure (fit) in association with pre-eclampsia, is rare but potentially life-threatening. Magnesium sulphate is the drug of choice for treating eclampsia. This review assesses its use for preventing eclampsia. To assess the effects of magnesium sulphate, and other anticonvulsants, for prevention of eclampsia. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (4 June 2010), and the Cochrane Central Register of Controlled Trials Register (The Cochrane Library 2010, Issue 3). Randomised trials comparing anticonvulsants with placebo or no anticonvulsant, or comparisons of different drugs, for pre-eclampsia. Two authors assessed trial quality and extracted data independently. We included 15 trials. Six (11,444 women) compared magnesium sulphate with placebo or no anticonvulsant: magnesium sulphate more than a halved the risk of eclampsia (risk ratio (RR) 0.41, 95% confidence interval (CI) 0.29 to 0.58; number needed to treat for an additional beneficial outcome (NNTB) 100, 95% CI 50 to 100), with a non-significant reduction in maternal death (RR 0.54, 95% CI 0.26 to 1.10) but no clear difference in serious maternal morbidity (RR 1.08, 95% CI 0.89 to 1.32). It reduced the risk of placental abruption (RR 0.64, 95% CI 0.50 to 0.83; NNTB 100, 95% CI 50 to 1000), and increased caesarean section (RR 1.05, 95% CI 1.01 to 1.10). There was no clear difference in stillbirth or neonatal death (RR 1.04, 95% CI 0.93 to 1.15). Side effects, primarily flushing, were more common with magnesium sulphate (24% versus 5%; RR 5.26, 95% CI 4.59 to 6.03; number need to treat for an additional harmful outcome (NNTH) 6, 95% CI 5 to 6).Follow-up was reported by one trial comparing magnesium sulphate with placebo: for 3375 women there was no clear difference in death (RR 1.79, 95% CI 0.71 to 4.53) or morbidity potentially related to pre-eclampsia (RR 0.84, 95% CI 0.55 to 1.26) (median follow-up 26 months); for 3283 children exposed in utero

Aluminium leaching from red mud by filamentous fungi.

Science.gov (United States)

Urík, Martin; Bujdoš, Marek; Milová-Žiaková, Barbora; Mikušová, Petra; Slovák, Marek; Matúš, Peter

2015-11-01

This contribution investigates the efficient and environmentally friendly aluminium leaching from red mud (bauxite residue) by 17 species of filamentous fungi. Bioleaching experiments were examined in batch cultures with the red mud in static, 7-day cultivation. The most efficient fungal strains in aluminium bioleaching were Penicillium crustosum G-140 and Aspergillus niger G-10. The A. niger G-10 strain was capable to extract up to approximately 141 mg·L(-1) of aluminium from 0.2 g dry weight red mud. Chemical leaching with organic acids mixture, prepared according to A. niger G-10 strain's respective fungal excretion during cultivation, proved that organic acids significantly contribute to aluminium solubilization from red mud. Copyright © 2015 Elsevier Inc. All rights reserved.

Determination of ultratrace amounts of uranium and thorium in aluminium and aluminium alloys by electrothermal vaporization/ICP-MS

International Nuclear Information System (INIS)

Nakamura, Yasushi; Kobayashi, Yoshio; Kakurai, Yousuke

1993-01-01

A method has been developed for determining the 0.01 ng g -1 level of uranium and thorium in aluminium and aluminium alloys by electrothermal vaporization (ETV)/ICP-MS. This method was found to be significantly interfered with any matrices or other elements contained. An ion-exchange technique was therefore applied to separate uranium and thorium from aluminium and other elements. It was known that uranium are adsorbed on an anion-exchange resin and thorium are adsorbed on cation-exchange resin. However, aluminium and copper were eluted with 6 M hydrochloric acid. Dissolve the sample with hydrochloric acid containing copper which was added for analysis of pure aluminium, and oxidize with hydrogen peroxide. Concentration of hydrochloric acid in the solution was adjusted to 6 M, and then passed the solution through the mixed ion-exchange resin column. After the uranium and thorium were eluted with 1 M hydrofluoric acid-0.1 M hydrochloric acid, the solution was evaporated to dryness. It was then dissolved with 1 M hydrochloric acid. Uranium and thorium were analyzed by ETV/ICP-MS using tungsten and molybdenum boats, respectively, since the tungsten boat contained high-level thorium and the molybdenum boat contained uranium. The determination limit of uranium and thorium were 0.003 and 0.005 ng g -1 , respectively. (author)

Method of Black Liquor Combustion to Remove Silicon from Wheat Straw Pulping

Directory of Open Access Journals (Sweden)

Yongjian Xu

2015-02-01

Full Text Available The effects of aluminium sulphate and sodium aluminate on physical and chemical properties of wheat straw pulp black liquor were studied. Results showed that the expansion rate was enhanced by increasing the aluminum salt content; furthermore, the effect of sodium aluminate was better than that of aluminum sulfate. The maximum desilication rate of 92.31% was reached with the addition of 3% sodium aluminate. A rheometer showed that aluminum salt had little impact on the viscosity of thick black liquor, so even at a high temperature it could be conveyed by pumps in paper mill at 110 °C. The effect of aluminium salt on the silicon removal rate during black liquor combustion was also studied. The experimental results showed that both aluminium sulphate and sodium aluminate helped to remove silicon. The desilication rate of sodium aluminate reached 62.33%, higher than that of aluminum sulphate. SEM-EDX illustrated that the aluminum and silicon ions were formed into insoluble precipitates. It was optimal to use 3% sodium aluminate as desilication agent.

Investigations concerning the effect of aluminium toxicity on the physiology and fine structures of oat plants. Physiologische und feinstrukturelle Untersuchungen zur Aluminium-Toxizitaet an Haferpflanzen

Energy Technology Data Exchange (ETDEWEB)

Marienfeld, S.

1992-06-30

In order to test the toxicity of aluminium to plants, two-week-old oat seedlings were exposed to aluminium concentrations of 0-400 [mu]M in the culture broth. Already after 12-24 hours a decrease in longitudinal root growth is to be noted, resulting from impaired mitosis activity of the root tip. This, and the observed premature cell differentiation are not aluminium-specific but unspecific reactions to unfavourable conditions. Shoot growth is only reduced after 3-4 days, and less so. Magnesium and calcium fertilization did enhance the growth of aluminium-stressed plants, but not to the level of the control plants, although the mineral concentration in the leaves reached normal values. Phosphate concentration in the root increased because of aluminium phosphate precipitation in the cell walls, which has detoxifying effect along with aluminium fixation to negative charges in the cell walls. Aluminium remains almost quantitatively in the cell wall area of the roots and is not accumulated in the cell core. Aluminium stress causes transpiration and CO[sub 2] uptake to be impaired as a reaction to the growth depression in the root area, even before the mineral concentration in the shoots is lowered. Later there follow chlorophyll depletion, chloroplast degradation, and a reduction of the leaf area. (UWA)

Friction stir welding (FSW of aluminium foam sandwich panels

Directory of Open Access Journals (Sweden)

M. Bušić

2016-07-01

Full Text Available The article focuses on the influence of welding speed and tool tilt angle upon the mechanical properties at the friction stir welding of aluminium foam sandwich panels. Double side welding was used for producing butt welds of aluminium sandwich panels applying insertion of extruded aluminium profile. Such insertion provided lower pressure of the tool upon the aluminium panels, providing also sufficient volume of the material required for the weldment formation. Ultimate tensile strength and flexural strength for three-point bending test have been determined for samples taken from the welded joints. Results have confirmed anticipated effects of independent variables.

Performance of cement solidification with barium for high activity liquid waste including sulphate

International Nuclear Information System (INIS)

Waki, Toshikazu; Yamada, Motoyuki; Horikawa, Yoshihiko; Kaneko, Masaaki; Saso, Michitaka; Haruguchi, Yoshiko; Yamashita, Yu; Sakai, Hitoshi

2009-01-01

The target liquid waste to be solidified is generated from PWR primary loop spent resin treatment with sulphate acid, so, its main constituent is sodium sulphate and the activity of this liquid is relatively high. Waste form of this liquid waste is considered to be a candidate for the subsurface disposal. The disposed waste including sulphate is anticipated to rise a concentration of sulphate ion in the ground water around the disposal facility and it may cause degradation of materials such as cement and bentonite layer and comprise the disposal facility. There could be two approaches to avoid this problem, the strong design of the disposal facility and the minimization of sulphaste ion migration from the solidified waste. In this study, the latter approach was examined. In order to keep the low concentration of sulphate ion in the ground water, it is effective to make barium sulphate by adding barium compound into the liquid waste in solidification. However, adding equivalent amount of barium compound with sulphate ion causes difficulty of mixing, because production of barium sulphate causes high viscosity. In this study, mixing condition after and before adding cement into the liquid waste was estimated. The mixing condition was set with consideration to keep anion concentration low in the ground water and of mixing easily enough in practical operation. Long term leaching behavior of the simulated solidified waste was also analyzed by PHREEQC. And the concentration of the constitution affected to the disposal facility was estimated be low enough in the ground water. (author)

Surface treatments for aluminium alloys

Science.gov (United States)

Ardelean, M.; Lascău, S.; Ardelean, E.; Josan, A.

2018-01-01

Typically, in contact with the atmosphere, the aluminium surface is covered with an aluminium oxide layer, with a thickness of less than 1-2μm. Due to its low thickness, high porosity and low mechanical strength, this layer does not protect the metal from corrosion. Anodizing for protective and decorative purposes is the most common method of superficial oxidation processes and is carried out through anodic oxidation. The oxide films, resulted from anodizing, are porous, have a thickness of 20-50μm, and are heat-resistant, stable to water vapour and other corrosion agents. Hard anodizing complies with the same obtains principles as well as decorative and protective anodization. The difference is in that hard anodizing is achieved at low temperatures and high intensity of electric current. In the paper are presented the results of decorative and hard anodization for specimens made from several aluminium alloys in terms of the appearance of the specimens and of the thickness of the anodized.

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

Directory of Open Access Journals (Sweden)

E. D. Wannaz

2012-01-01

Full Text Available 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.

Aluminium/iron reinforced polyfurfuryl alcohol resin as advanced biocomposites

Directory of Open Access Journals (Sweden)

Rakesh Kumar

2016-07-01

Full Text Available Aluminium and iron are widely used in construction sectors for the preparation of advanced composites with epoxy resins as matrices. In recent times, there are several reports on the polymerization of polyfufuryl alcohol (PFA a thermoset bioresins from furfuryl alcohol (FA. FA is obtained from waste of sugarcane bagasse. In this work, first the possibility of curing PFA from FA in the presence of aluminium or iron has been explored. Absorbance results from colorimeter/spectrophotometerindicated that the curing of FA to PFA in presence of aluminium started easily while in presence of iron the curing of FA to PFA could not start. Based on the above results, aluminium wire reinforced composites were successfully prepared with three different weight fractions (0.13, 0.09 and 0.07 of aluminium wire. The mechanical properties of these composites were determined theoretically and reported.

The aqueous solubility of ofloxacin in the presence of metallic cations

African Journals Online (AJOL)

Ferrous sulphate produced the greatest increase in the solubility of ofloxacin. It was followed by ferric ammonium citrate, magnesium sulphate, aluminium hydroxide and calcium carbonate. Potassium chloride and sodium bicarbonate produced very slight increases. In all the cases, the solubility of ofloxacin increased as the ...

Volatilisation and oxidation of aluminium scraps fed into incineration furnaces

Energy Technology Data Exchange (ETDEWEB)

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

2012-12-15

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

Aluminium allergy and granulomas induced by vaccinations for children

DEFF Research Database (Denmark)

Andersen, Rosa Marie O; Zachariae, Claus; Johansen, Jeanne Duus

2014-01-01

Vaccination with aluminium-adsorbed vaccines can induce aluminium allergy with persistent itching subcutaneous nodules at the injection site - vaccination granulomas. In this article we give an overview of childhood aluminium-adsorbed vaccines available in Denmark. Through literature studies we...... examine the incidence, the symptoms and the prognosis for the vaccination granulomas and the allergy. Finally we discuss the status in Denmark....

Hot workability of aluminium alloys

International Nuclear Information System (INIS)

Yoo, Yeon Chul; Oh, Kyung Jin

1986-01-01

Hot Workability of aluminium alloys, 2024, 6061 and 7075, has been studied by hot torsion tests at temperatures from 320 to 515 deg C and at strain rates from 1.26 x 10 -3 to 5.71 x 10 -3 sec -1 . Hot working condition of these aluminium alloys was determined quantitatively from the constitutive equations obtained from flow stress curves in torsion. Experimental data of the logarith of the Zener-Hollomonn parameter showed good linear relationships to the logarith of sinh(ασ-bar)

Aluminium toxicity tolerance in crop plants: Present status of research

African Journals Online (AJOL)

... tolerance of which genes of the Aluminium-activated malate transporter (ALMT) and multidrug and toxic compound extrusion (MATE) families are prominent. In this review, the progress of research in identifying aluminium toxicity tolerant genes is discussed. Keywords: Aluminium toxicity, soil acidity, hydroponic screening, ...

Compressive Behaviour and Energy Absorption of Aluminium Foam Sandwich

Science.gov (United States)

Endut, N. A.; Hazza, M. H. F. Al; Sidek, A. A.; Adesta, E. T. Y.; Ibrahim, N. A.

2018-01-01

Development of materials in automotive industries plays an important role in order to retain the safety, performance and cost. Metal foams are one of the idea to evolve new material in automotive industries since it can absorb energy when it deformed and good for crash management. Recently, new technology had been introduced to replace metallic foam by using aluminium foam sandwich (AFS) due to lightweight and high energy absorption behaviour. Therefore, this paper provides reliable data that can be used to analyze the energy absorption behaviour of aluminium foam sandwich by conducting experimental work which is compression test. Six experiments of the compression test were carried out to analyze the stress-strain relationship in terms of energy absorption behavior. The effects of input variables include varying the thickness of aluminium foam core and aluminium sheets on energy absorption behavior were evaluated comprehensively. Stress-strain relationship curves was used for energy absorption of aluminium foam sandwich calculation. The result highlights that the energy absorption of aluminium foam sandwich increases from 12.74 J to 64.42 J respectively with increasing the foam and skin thickness.

Investigation of different anode materials for aluminium rechargeable batteries

Science.gov (United States)

Muñoz-Torrero, David; Leung, Puiki; García-Quismondo, Enrique; Ventosa, Edgar; Anderson, Marc; Palma, Jesús; Marcilla, Rebeca

2018-01-01

In order to shed some light into the importance of the anodic reaction in reversible aluminium batteries, we investigate here the electrodeposition of aluminium in an ionic liquid electrolyte (BMImCl-AlCl3) using different substrates. We explore the influence of the type of anodic material (aluminium, stainless steel and carbon) and its 3D geometry on the reversibility of the anodic reaction by cyclic voltammetry (CV) and galvanostatic charge-discharge. The shape of the CVs confirms that electrodeposition of aluminium was feasible in the three materials but the highest peak currents and smallest peak separation in the CV of the aluminium anode suggested that this material was the most promising. Interestingly, carbon-based substrates appeared as an interesting alternative due to the high peak currents in CV, moderate overpotentials and dual role as anode and cathode. 3D substrates such as fiber-based carbon paper and aluminium mesh showed significantly smaller overpotentials and higher efficiencies for Al reaction suggesting that the use of 3D substrates in full batteries might result in enhanced power. This is corroborated by polarization testing of full Al-batteries.

Aluminium Electroplating on Steel from a Fused Bromide Electrolyte

Energy Technology Data Exchange (ETDEWEB)

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

2014-08-01

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

Effect of temperature on sulphate reduction, growth rate and growth yield in five psychrophilic sulphate-reducing bacteria from Arctic sediments

DEFF Research Database (Denmark)

Knoblauch, C.; Jørgensen, BB

1999-01-01

Five psychrophilic sulphate-reducing bacteria (strains ASv26, LSv21, PSv29, LSv54 and LSv514) isolated from Arctic sediments were examined for their adaptation to permanently low temperatures, All strains grew at -1.8 degrees C, the freezing point of sea water, but their optimum temperature...... and T(opt). For strains LSv21 and LSv514, however, growth yields were highest at the lowest temperatures, around 0 degrees C. The results indicate that psychrophilic sulphate-reducing bacteria are specially adapted to permanently low temperatures by high relative growth rates and high growth yields...... at in site conditions....

Characterisation and concentration profile of aluminium during ...

African Journals Online (AJOL)

An aluminium(Al) characterisation study was conducted at a surface water treatment plant (Buffalo Pound Water Treatment Plant (BPWTP) in Moose Jaw, Saskatchewan, Canada) to understand better the effect of alum coagulant on various Al fractions. The raw water source for BPWTP is Buffalo Pound Lake water. The Al ...

Complete sulphate removal from neutralised acidic mine drainage with barium carbonate

CSIR Research Space (South Africa)

Swanepoel, H

2012-03-01

Full Text Available -barium-calcium) Desalination process which uses barium salts to further reduce the sulphate concentration to acceptable levels with the added advantage that sulphate removal can be controlled due to the low solubility of BaSO4. This paper reports on the results...

Feet sunk in molten aluminium: The burn and its prevention.

Science.gov (United States)

Alonso-Peña, David; Arnáiz-García, María Elena; Valero-Gasalla, Javier Luis; Arnáiz-García, Ana María; Campillo-Campaña, Ramón; Alonso-Peña, Javier; González-Santos, Jose María; Fernández-Díaz, Alaska Leonor; Arnáiz, Javier

2015-08-01

Nowadays, despite improvements in safety rules and inspections in the metal industry, foundry workers are not free from burn accidents. Injuries caused by molten metals include burns secondary to molten iron, aluminium, zinc, copper, brass, bronze, manganese, lead and steel. Molten aluminium is one of the most common causative agents of burns (60%); however, only a few publications exist concerning injuries from molten aluminium. The main mechanisms of lesion from molten aluminium include direct contact of the molten metal with the skin or through safety apparel, or when the metal splash burns through the pants and rolls downward along the leg. Herein, we report three cases of deep dermal burns after 'soaking' the foot in liquid aluminium and its evolutive features. This paper aims to show our experience in the management of burns due to molten aluminium. We describe the current management principles and the key features of injury prevention. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

Corrosion of Metal-Matrix Composites with Aluminium Alloy Substrate

Directory of Open Access Journals (Sweden)

B. Bobic

2010-03-01

Full Text Available The corrosion behaviour of MMCs with aluminium alloy matrix was presented. The corrosion characteristics of boron-, graphite-, silicon carbide-, alumina- and mica- reinforced aluminium MMCs were reviewed. The reinforcing phase influence on MMCs corrosion rate as well as on various corrosion forms (galvanic, pitting, stress corrosion cracking, corrosion fatique, tribocorrosion was discussed. Some corrosion protection methods of aluminium based MMCs were described

Cold forming of aluminium - State of the art

DEFF Research Database (Denmark)

Bay, Niels

1997-01-01

The ongoing development of cold forging technology has been manifested lately by the increasing application of components in cold forged aluminium alloys. Applying precipitation hardening alloys components with great strength/weight ratio can be produced with a strength comparable...... to that of unalloyed steel. After description of the different types of alloys and their individual properties and applications, the special requirements for tool design by cold forging in aluminium is discussed. Finally, a large number of industrial examples on cold forged aluminium components are presented. (C) 1997...

Effect of pressurized steam on AA1050 aluminium

DEFF Research Database (Denmark)

Jariyaboon, Manthana; Møller, Per; Ambat, Rajan

2012-01-01

Purpose - The purpose of this paper is to understand the effect of pressurized steam on surface changes, structures of intermetallic particles and corrosion behavior of AA1050 aluminium. Design/methodology/approach - Industrially pure aluminium (AA1050, 99.5 per cent) surfaces were exposed...... reactivities was observed due to the formation of the compact oxide layer. Originality/value - This paper reveals a detailed investigation of how pressurized steam can affect the corrosion behaviour of AA1050 aluminium and the structure of Fe-containing intermetallic particles....

Characterization of aluminium alloys rapidly solidified

International Nuclear Information System (INIS)

Monteiro, W.A.

1988-01-01

This paper discussed the investigation of the microstructural and mechanical properties of the aluminium alloys (3003; 7050; Al-9% Mg) rapidly solidified by melt spinning process (cooling rate 10 4 - 10 6 K/s). The rapidly solidification process of the studied aluminium alloys brought a microcrystallinity, a minimum presence of coarse precipitation and, also, better mechanical properties of them comparing to the same alloys using ingot process. (author) [pt

Control strategies for bovine dermatophilosis with particular ...

African Journals Online (AJOL)

The various control strategies for Dermatophilosis are discussed in this paper. Recommendations for control of Dermatophilosis in Nigeria on short term include ecto-parasite control by regular use of insecticide/acaricide in dips with added 0.03% copper sulphate or 1% solution of alum (potassium aluminium sulphate) ...

Sinter aluminium as cladding material for fuel elements; Aluminium fritte comme materiau de gainage pour les elements combustibles

Energy Technology Data Exchange (ETDEWEB)

Mann, K E; Boudouresques, M B [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Otto Fuchs, Meinerzhagen, Westfalen (Germany)

1961-07-01

1. Survey of the production process of sinter aluminium. 2. Description of the forming processes (extrusion, forging and rolling), whereby the production of tubing for atom piles will be explained in detail. 3. Production of ribbed tubes and tubes with close tolerances of sizes. 4. The different SAP-qualities and their properties under special consideration of the properties at elevated temperatures and the creep properties. 5. Diffusion behaviour of SAP with Be, Mg, Al, U and UO{sub 2}. 6. Corrosion behaviour in CO{sub 2} atmosphere at high temperature and in water. 7. Weldability. 8. Effect of irradiation on the mechanical properties. 9. Superiority of SAP compared with normal wrought alloys of the same composition. (author) [French] 1. Apercu des processus de production de l'aluminium fritte. 2. Expose des operations de transformation (filageries, forgeage et laminage), avec explication detaillee de la fabrication de gaine pour reacteurs. 3. Fabrication de tubes canneles et de tubes avec de faibles tolerances. 4. Diverses proprietes de l'aluminium fritte SAP, notamment proprietes aux temperatures elevees et proprietes de fluage. 5. Diffusion de l'aluminium fritte SAP en presence de Be, Mg, Al, U et UO{sub 2}. 6. Resistance a la corrosion dans une atmosphere de CO{sub 2} a temperature elevee et dans l'eau. 7. Possibilites de soudage. 8. Effet de l'irradiation sur les proprietes mecaniques. 9. Superiorite de l'aluminium fritte SAP sur les alliages forges normaux de meme composition. (auteur)

Low temperature oxidation of niobium alloy with silicon-aluminium coating

International Nuclear Information System (INIS)

Lazarev, Eh.M.; Sapozhnikova, L.V.; Shabanova, M.E.; Pod'yachev, V.N.; Kornilova, Z.I.

1987-01-01

Using the gravimetry methods heat resistance of niobium-titanium-aluminium alloy in the air and at 700 deg C in the initial state and when it is protected by silicide-aluminium coatings (with variable content of aluminium) is investigated. Using X-ray diffraction and micro X-ray diffraction analyses, mechanisms of the alloy oxidation and the coating protective effect are studied. The role of aluminium in the formation of coatings is analyzed and according to bend tests the plasticity of the coatings is evaluated

Development of melt compositions for sulphate bearing high level waste

International Nuclear Information System (INIS)

Jahagirdar, P.B.; Wattal, P.K.

1997-09-01

The report deals with the development and characterization of vitreous matrices for sulphate bearing high level waste. Studies were conducted in sodium borosilicate and lead borosilicate systems with the introduction of CaO, BaO, MgO etc. Lead borosilicate system was found to be compatible with sulphate bearing high level wastes. Detailed product evaluation carried on selected formulations is also described. (author)

The structure of high-quality aluminium cast iron

Directory of Open Access Journals (Sweden)

D. Kopyciński

2012-01-01

Full Text Available In this study presents the analyse of aluminium iron cast structure (as-cast condition which are used in high temperature. While producing the casts of aluminium iron major influence has been preserve the structure of technological process parameters. The addition to Fe-C-Al alloy V, Ti, Cr leads to the improvement of functional and mechanical cast qualities. In this study, a method was investigated to eliminate the presence of undesirable Al4C3 phases in a aluminium cast iron structure and thus improve the production process. V and Ti additions in aluminium cast iron allows to development of FeAl - VC or TiC alloys. In particular, V or Ti contents above 5 wt.% were found to totally eliminate the presence of Al4C3. In addition, preliminary work indicates that the alloy with the FeAl - VC or TiC structure reveals high oxidation resistance. The introduction of 5 wt.% chromium to aluminium cast iron strengthened Al4C3 precipitate. Thus, the resultant alloy can be considered an intermetallic FeAl matrix strengthened by VC and TiC or modified Al4C3 reinforcements.

Method of preparing an Al-Ti-B grain refiner for aluminium-comprising products, and a method of casting aluminium products

NARCIS (Netherlands)

Brinkman, H.J.; Duszczyk, J.; Katgerman, L.

1999-01-01

The invention relates to a method of preparing an Al-Ti-B grain refiner for cast aluminium-comprising products. According to the invention the preparation is realized by mixing powders selected from the group comprising aluminium, titanium, boron, and alloys and intermetallic compounds thereof,

Recovery of tritium from lithium-sintered aluminium product (SAP) and lithium-aluminium alloys

International Nuclear Information System (INIS)

Talbot, J.B.; Wiffen, F.W.

1979-01-01

The tritium release rates of irradiated samples of lithium-containing aluminium (Li-Al) and sintered aluminium product (Li-SAP) were investigated to evaluate the potential application of both materials in fusion reactors. The observed release rates followed the pattern expected for bulk diffusion of tritium in a solid. Therefore, diffusion coefficients for tritium in Li-SAP were determined over a temperature range of 383 and 500 0 C and tritium in Li-Al at 450 0 C. At 450 0 C, the diffusion coefficients of tritium in Li-SAP and Li-Al are 2.988 x 10 -10 cm 2 sec -1 and 1.462 x 10 -6 cm 2 sec -1 , respectively. (author)

Thermal formation of corundum from aluminium hydroxides ...

Indian Academy of Sciences (India)

Aluminium hydroxides have been precipitated from various aluminium salts and the differences in their thermal behaviour have been investigated. Pseudoboehmite derived from the nitrate, sulfate and chloride all form -Al2O3 at ∼ 400°C but the formation of -Al2O3 at 1200°C occurs more readily in the material derived ...

Thermal formation of corundum from aluminium hydroxides ...

Indian Academy of Sciences (India)

Abstract. Aluminium hydroxides have been precipitated from various aluminium salts and the differences in their thermal behaviour have been investigated. Pseudoboehmite derived from the nitrate, sulfate and chloride all form γ-Al2O3 at ~ 400°C but the formation of α-Al2O3 at 1200°C occurs more readily in the material ...

Influence of Alkali Treatment on the Surface Area of Aluminium Dross

Directory of Open Access Journals (Sweden)

N. S. Ahmad Zauzi

2016-01-01

Full Text Available Aluminium dross is an industrial waste from aluminium refining industry and classified as toxic substances. However, the disposal of dross as a waste is a burden to aluminium manufacturer industries due to its negative effects to the ecosystem, surface, and ground water. Therefore the purpose of this study is to evaluate the influence of sodium hydroxide (NaOH on the surface area and pore size of aluminium dross. There were 3 stages in the treatment activities, which were leaching, precipitation, and calcination process. The optimum result from this study was the surface area of aluminium dross increases from 10.1 m2/g up to 80.0 m2/g at 40°C, 1% NaOH, and 15-minute reaction time. Thus, aluminium dross has a potential to be converted into other useful material such as catalyst and absorbent. The benefit of this research is that the hazardous industrial waste can be turned into wealth to be used in other applications such as in catalytic activities and absorber in waste water treatment. Further investigation on the physicochemical of aluminium dross with different acid or alkali should be conducted to get deeper understanding on the aluminium dross as a catalyst-type material.

Elastic and plastic properties of iron-aluminium alloys. Special problems raised by the brittleness of alloys of high aluminium content; Proprietes elastiques et plastiques des alliages fer-aluminium. Problemes particuliers poses par la fragilite des alliages a forte teneur en aluminium

Energy Technology Data Exchange (ETDEWEB)

Mouturat, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1966-06-01

The present study embodies the results obtained with iron-aluminium alloys whose composition runs from 0 to nearly 50 atoms per cent aluminium. Conditions of elaboration and transformation have been studied successively, as well as the Young's modulus and the flow stress; the last chapter embodies, a study of the Portevin-le-Chatelier effect in alloys of 40 atoms per cent of aluminium. I) The principal difficulty to clear up consisted in the intergranular brittleness of ordered alloys; this brittleness has been considerably reduced with appropriate conditions of elaboration and transformation. II) The studies upon the Young's modulus are in connection with iron-aluminium alloys; transformation temperatures are well shown up. The formation of covalent bonds on and after 25 atoms per cent show the highest values of the modulus. III) The analysis of variations of the flow stress according to the temperature show some connection with ordered structures, the existence of antiphase domains and the existence of sur-structure dislocations. IV) In the ordered Fe Al domain the kinetics of the Portevin-le-Chatelier effect could be explained by a mechanism of diffusion of vacancies. The role they play has been specified by the influence they exert upon the dislocations; this has led us to the inhomogeneous Rudman order; this inhomogeneous order could explain the shape of the traction curves. (author) [French] Cette etude comporte les resultats obtenus avec des alliages fer-aluminium dont la composition s'etend de 0 a pres de 50 atomes pour cent d'aluminium. Nous avons etudie successivement les conditions d'elaboration et de transformation, le module elastique et la limite elastique; un dernier chapitre est consacre a l'etude du phenomene Portevin-le-Chatelier dans les alliages a 40 atomes pour cent d'aluminium. I) La principale difficulte a resoudre residait dans la fragilite intergranulaire des alliages ordonnes; celle-ci a ete considerablement reduite par des conditions

Polymer composite adsorbents using particles of molecularly imprinted polymers or aluminium oxide nanoparticles for treatment of arsenic contaminated waters.

Science.gov (United States)

Önnby, L; Pakade, V; Mattiasson, B; Kirsebom, H

2012-09-01

Removal of As(V) by adsorption from water solutions was studied using three different synthetic adsorbents. The adsorbents, (a) aluminium nanoparticles (Alu-NPs, polymers (polymer backbones of pure polyacrylamide (MIP-cryo) were of better stability than the amine containing polymer backbone (Alu-cryo). Both composites worked well in the studied pH range of pH 2-8. Adsorption tested in real wastewater spiked with arsenic showed that co-ions (nitrate, sulphate and phosphate) affected arsenic removal for Alu-cryo more than for MIP-cryo. Both composites still adsorbed well in the presence of counter-ions (copper and zinc) present at low concentrations (μg/l). The unchanged and selective adsorption in realistic water observed for MIP-cryo was concluded to be due to a successful imprinting, here controlled using a non-imprinted polymer (NIP). A development of MIP-cryo is needed, considering its low adsorption capacity. Copyright © 2012 Elsevier Ltd. All rights reserved.

Differential inhibition of polymorphonuclear leukocyte recruitment in vivo by dextran sulphate and fucoidan

Directory of Open Access Journals (Sweden)

N. Van Osselaer

1996-01-01

Full Text Available The selectin-mediated rolling of leukocytes along the endothelial cells is a prerequisite step followed by firm adhesion and extravasation into the inflamed tissue. This initial contact can be suppressed by sulphated polysaccharides. We have studied the effect of sulphated polysaccharides on the ultimate polymorphonuclear leukocyte (PMN recruitment and plasma leakage in rabbit skin in response to intradermal injection of various inflammatory mediators. PMN infiltration evoked by various PMN chemoattractants (FMLP, C5a desArg, LTB4 and IL-8 was significantly inhibited after intravenous injection of dextran sulphate (25 mg/kg, heparin (2 × 90 mg/kg or fucoidan (1 mg/kg. PMN-dependent plasma leakage was equally well reduced by the different sulphated polymers. Vascular permeability induced by histamine or thrombin acting via a PMN-independent mechanism was not reduced. Fucoidan was the only polysaccharide able to suppress IL-1-induced PMN infiltration for 60–70%. Local administration of dextran sulphate had no effect on PMN-dependent plasma leakage. Differential inhibition of PMN recruitment was determined after injection of dextran sulphate or fucoidan depending on the type of insult. Therefore, these results suggest that different adhesion pathways are utilized during PMN recruitment in vivo in response to chemoattractants and IL-1.

The reducibility of sulphuric acid and sulphate in aqueous solution (translated from German)

International Nuclear Information System (INIS)

Grauer, R.

1990-07-01

In connection with the Swedish project for the final storage of spent fuel elements it was necessary to assess whether dissolved sulphate can corrode the copper canister without the intervention of sulphate-reducing bacteria. A simple reaction between copper and sulphate is thermodynamically impossible. On the other hand, copper can react to give copper sulphide if an additional electron donor such as iron is available. Because little specific information is available about this subject the problem was extended to the much more general question of the reducibility of sulphur in dilute aqueous solution. It is a part of the general knowledge of chemistry, and there is also unanimity about it in the geochemical literature, that purely chemical reduction of sulphate does not take place in dilute solution at temperatures below 100 degrees C. This fact is, however, poorly documented and it was therefore necessary to substantiate it by drawing on numerous individual findings from different areas of pure and applied chemistry. The investigation confirms that sulphur in dilute solution is completely inert towards chemical reducing agents and also to cathodic reduction. Thus corrosion of copper by sulphate under final-storage conditions and in the absence of sulphate reducing bacteria can be ruled out with a probability verging on certainty. (85 refs.)

The binding, transport and fate of aluminium in biological cells.

Science.gov (United States)

Exley, Christopher; Mold, Matthew J

2015-04-01

Aluminium is the most abundant metal in the Earth's crust and yet, paradoxically, it has no known biological function. Aluminium is biochemically reactive, it is simply that it is not required for any essential process in extant biota. There is evidence neither of element-specific nor evolutionarily conserved aluminium biochemistry. This means that there are no ligands or chaperones which are specific to its transport, there are no transporters or channels to selectively facilitate its passage across membranes, there are no intracellular storage proteins to aid its cellular homeostasis and there are no pathways which evolved to enable the metabolism and excretion of aluminium. Of course, aluminium is found in every compartment of every cell of every organism, from virus through to Man. Herein we have investigated each of the 'silent' pathways and metabolic events which together constitute a form of aluminium homeostasis in biota, identifying and evaluating as far as is possible what is known and, equally importantly, what is unknown about its uptake, transport, storage and excretion. Copyright © 2014 Elsevier GmbH. All rights reserved.

Influence on ammonium-sulphate fertilizer on P-uptake by upland rice

International Nuclear Information System (INIS)

Abdullah, N; Mitrosuhardjo, M.M.

1988-01-01

A greenhouse experiment to study the influence of ammonium -sulphate fertilizer on P-uptake by Atomita I/1 rice variety on latosol soil of Pasar Jumat has been conducted. Factorial experiment consisting of eight treatments was arrange in a fully randomized design. Each treatment was replicated three times. The rate of ammonium sulphate fertilizer was equivalent to 0, 30, 60, and 90 kg N/ha, and TSP at the rate of 90 and 180 kg P/ha. Ammonium sulphate fertilizer with 2% atom 15-N and TSP with specific activity of 0.2 mCi/g P2O5 were used in the experiment. The plant was harvested 70 days after planting, It was turned out that ammonium sulphate fertilizer gave a highly significant difference (p=<0.01) of dry weight of plant. The rate of TSP did not effect significantly on plant dry weight. Ammonium sulphate fertilizer gave highly significant difference on P-uptake. Fertilizer use efficiency was in the range of 3.88 - 6.60% for 90 kg P and 2.51 - 4.46% for 180 kg P. Fertilizer-N uptake was significantly increased (p=<0.05) with the increase of N rate. Rate of fertilizer-N use efficiency was in the range of 47-60% of the applied fertilizer. (authors). 4 refs, 9 tabs

Wear and chemistry of zirconium-silicate, aluminium-silicate and zirconium-aluminium-silicate glasses in alkaline medium

International Nuclear Information System (INIS)

Rouse, C.G.; Lemos Guenaga, C.M. de

1984-01-01

A study of the chemical durability, in alkaline solutions, of zirconium silicate, aluminium silicate, zirconium/aluminium silicate glasses as a function of glass composition is carried out. The glasses were tested using standard DIN-52322 method, where the glass samples are prepared in small polished pieces and attacked for 3 hours in a 800 ml solution of 1N (NaOH + NA 2 CO 3 ) at 97 0 C. The results show that the presence of ZrO 2 in the glass composition increases its chemical durability to alkaline attack. Glasses of the aluminium/zirconium silicate series were melted with and without TiO 2 . It was shown experimentally that for this series of glasses, the presence of both TiO 2 and ZrO 2 gave better chemical durability results. However, the best overall results were obtained from the simpler zirconium silicate glasses, where it was possible to make glasses with higher values of ZrO 2 . (Author) [pt

Tyrosine sulphation is not required for microvillar expression of intestinal aminopeptidase N

DEFF Research Database (Denmark)

Danielsen, E M

1988-01-01

incorporation of [35S]sulphate into aminopeptidase N and other major microvillar hydrolases by 70-85% compared with controls, indicating an inhibition of their post-translational tyrosine sulphation. In labelling experiments with [35S]methionine from 0.5 to 5 h, DCNP was tested for its possible influence...... on synthesis, processing and microvillar expression of aminopeptidase N, but no effect on any of these parameters could be detected. It can therefore be concluded that tyrosine sulphation is not required (for instance as a sorting signal) for the targeting of newly synthesized enzymes to the microvillar...

Aluminium effect on the physical properties of titanium

International Nuclear Information System (INIS)

Nazimov, O.P.; Il'in, A.A.; Zvonova, L.N.

1977-01-01

The effect of aluminium on the physical properties of titanium was investigated. Within the framework of the configuration model of matter it is shown that a change in physical properties with an aluminium content of up to 7.5 wt.% in alloys depends on the phase composition and electron structure. In interacting with titanium, aluminium exhibits acceptor properties, causing d→s electron transitions. The electrons which have shifted to the s-state are partly collectivized and partly localized into quasistable sp 3 configurations, with the resulting increase of the interatomic forces. An intensification of d→s transitions in alloying of titanium with aluminium stabilizes the α-phase. Predominance of d 1 configurations in the intermediate spectrum in the region of the α-solution increases the ratio of the axes of the HCP lattice and determines the electron type of conduction of alloys of the Ti-Al system

Experimental Realisation of Elusive Multiple-bonded Aluminium Compounds: A New Horizon in the Aluminium Chemistry.

Science.gov (United States)

Inoue, Shigeyoshi; Bag, Prasenjit; Weetman, Catherine

2018-05-23

Synthesis and isolation of stable main group compounds featuring multiple bonds has been of keen interest for the last several decades. Multiply bonded complexes were obtained using sterically demanding substituents that provide kinetic and thermodynamic stability. Many of these compounds have unusual structural and electronic properties that challenges the classical concept of covalent multiple bonding. In contrast, analogous aluminium compounds are scarce in spite of its high natural abundance. The parent dialumene (Al2H2) has been calculated to be extremely weak, thus making Al multiple bonds a challenging synthetic target. This review provides an overview of these recent advances in the cutting edge synthetic approaches used to obtain aluminium homo- and heterodiatomic multiply bonded complexes. Additionally, the reactivity of these novel compounds towards various small molecules and reagents will be discussed herein. This review provides an overview on the current progress in aluminium multiple bond chemistry and the careful ligand design required to stabilise these reactive species. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Sintered aluminium powders

International Nuclear Information System (INIS)

Stepanova, M.G.; Matveev, B.I.

1974-01-01

The mechanical and physical properties of aluminium powder alloys and the various methods employed to produce them are considered. Data are given on the hardening of the alloys SAP and SPAK-4, as well as the powder-alloy system Al-Cr-Zr. (L.M.)

Silane based coating of aluminium mold

DEFF Research Database (Denmark)

2013-01-01

having at least one closed cavity is provided, at least one surface of the at least one cavity being an aluminium surface coated with a silane based coating layer. The silane based anti-stiction coating improves the anti-stiction properties of the mold which may allow for molding and demolding...... of structures which would otherwise be difficult to mold. The resistance of the coated aluminium mold is significantly improved by applying a silane-based coating layer....

Aluminium hydroxide-induced granulomas in pigs

DEFF Research Database (Denmark)

Valtulini, S; Macchi, C; Ballanti, P

2005-01-01

The effect of intramuscular injection of 40 mg/2 ml aluminium hydroxide in the neck of pigs was examined in a number of ways. The investigation followed repeated slaughterhouse reports, according to which 64.8% of pigs from one particular farm were found at slaughter to have one or more nodules...... in the muscles of the neck (group slaughtered). The pigs had been injected with a vaccine containing 40 mg/2 ml dose of aluminium hydroxide as adjuvant. Research consisted of two phases: first, an epidemiological study was carried out, aimed at determining the risk factors for the granulomas. The results...... and adjuvant) to pigs inoculated twice with apyrogenic bi-distilled water (group water) and to pigs inoculated once with the adjuvant and once with apyrogenic bi-distilled water (group adjuvant/water). Both studies agreed in their conclusions, which indicate that the high amount of aluminium hydroxide...

Oxygen isotopic composition of sulphates from some mineral waters and mine waters in western Bohemia

International Nuclear Information System (INIS)

Smejkal, V.

1979-01-01

Two main genetic types of sulphate can be distinguished according to the delta 18 O(SO 4 2- ) measurements in sulphate-rich mineral and mine waters of western Bohemia - sulphates in descending mine waters and in weathered outcrops of graphitic pyrite slates from areas outside Tertiary basins, which originated in recent time by the oxidation of sulphides in the presence of atmospheric oxygen, have delta 18 O values from -2.1 to -6.1 per mille SMOW; and sulphates from springs of mineral waters of the renowned spas of Karlovy Vary, Frantiskovy Lazne and Marianske Lazne show distinctly heavier delta 18 O values - from +4.0 to +6.4 per mille, with maximum of values between +5.0 and +6.0 per mille. Similar delta 18 O values have been established in thenardites and in gypsum in Miocene claystones and in sulphates of some mine waters in the nearby Tertiary Cheb and Sokolov Basins. The presented results indicate that sulphates in mineral waters of the Karlovy Vary type originate mainly by leaching of Miocene sulphates and not by present-day oxidation of sulphidic sulphur. (author)

Finite size melting of spherical solid-liquid aluminium interfaces

DEFF Research Database (Denmark)

Chang, J.; Johnson, Erik; Sakai, T.

2009-01-01

We have investigated the melting of nano-sized cone shaped aluminium needles coated with amorphous carbon using transmission electron microscopy. The interface between solid and liquid aluminium was found to have spherical topology. For needles with fixed apex angle, the depressed melting tempera...... to the conclusion that the depressed melting temperature is not controlled solely by the inverse radius 1/R. Instead, we found a direct relation between the depressed melting temperature and the ratio between the solid-liquid interface area and the molten volume.......We have investigated the melting of nano-sized cone shaped aluminium needles coated with amorphous carbon using transmission electron microscopy. The interface between solid and liquid aluminium was found to have spherical topology. For needles with fixed apex angle, the depressed melting...

Possibilities of Sulphate Elimination from Mine Water

Directory of Open Access Journals (Sweden)

Heviánková Silvie

2004-12-01

Full Text Available The issue of „acid water“ (or AMD is well known in the world for some centuries. In the Eastern Slovakia, the most acid surface water occurs in the area of old mine Smolník, which is closed and submerged for 15 years. The submitted contribution deals with the sulphate-elimination from this locality. Recently, several methods of sulphate-elimination from the mine water are applied. The best-known methods are biological, physical-chemical and chemical precipitation. The method described in this contribution consists of chemical precipitation by sodium aluminate and calcium hydrate. Under application of this method very interesting results were obtained. The amount of SO42- anions decreased to almost zero-value, using optimal doses of the chemical reagents.

Structural perturbation of diphtheria toxoid upon adsorption to aluminium hydroxide adjuvant

NARCIS (Netherlands)

Regnier, M.; Metz, B.; Tilstra, W.; Hendriksen, C.; Jiskoot, W.; Norde, W.; Kersten, G.

2012-01-01

Aluminium-containing adjuvants are often used to enhance the potency of vaccines. In the present work we studied whether adsorption of diphtheria toxoid to colloidal aluminium hydroxide induces conformational changes of the antigen. Diphtheria toxoid has a high affinity for the aluminium hydroxide

Long Term Effects of Acid Irrigation at the Hoeglwald on Seepage Water Chemistry and Nutrient Cycling

International Nuclear Information System (INIS)

Weis, Wendelin; Baier, Roland; Huber, Christian; Goettlein, Axel

2007-01-01

In order to test the hypothesis of aluminium toxicity induced by acid deposition, an experimental acid irrigation was carried out in a mature Norway spruce stand in Southern Germany (Hoeglwald). The experiment comprised three plots: no irrigation, irrigation (170 mm a -1 ), and acid irrigation with diluted sulphuric acid (pH of 2.6-2.8). During the seven years of acid irrigation (1984-1990) water containing 0.43 mol c m -2 a -1 of protons and sulphate was added with a mean pH of 3.2 (throughfall + acid irrigation water) compared to 4.9 (throughfall) on both control plots. Most of the additional proton input was consumed in the organic layer and the upper mineral soil. Acid irrigation resulted in a long lasting elevation of sulphate concentrations in the seepage water. Together with sulphate both aluminium and appreciable amounts of base cations were leached from the main rooting zone. The ratio between base cations (Ca + Mg + K) and aluminium was 0.79 during acid irrigation and 0.92 on the control. Neither tree growth and nutrition nor the pool of exchangeable cations were affected significantly. We conclude that at this site protection mechanisms against aluminium toxicity exist and that additional base cation runoff can still be compensated without further reduction of the supply of exchangeable base cations in the upper mineral soil

Disruption of an Alumina Layer During Sintering of Aluminium in Nitrogen

Directory of Open Access Journals (Sweden)

Pieczonka T.

2017-06-01

Full Text Available Aluminium oxide layer on aluminium particles cannot be avoided. However, to make the metal-metal contacts possible, this sintering barrier has to be overcome in some way, necessarily to form sintering necks and their development. It is postulated that the disruption of alumina layer under sintering conditions may originate physically and chemically. Additionally, to sinter successfully non alloyed aluminium powder in nitrogen, the operation of both types mechanism is required. It is to be noted that metallic aluminium surface has to be available to initiate reactions between aluminium and the sintering atmosphere, i.e. mechanical disruption of alumina film precedes the chemical reactions, and only then chemically induced mechanisms may develop. Dilatometry, gravimetric and differential thermal analyses, and microstructure investigations were used to study the sintering response of aluminium at 620°C in nitrogen, which is the only sintering atmosphere producing shrinkage.

Recycled Aluminium Cans/Eggshell Composites: Evaluation of Mechanical and Wear Resistance Properties

Directory of Open Access Journals (Sweden)

J.O. Agunsoye

2015-03-01

Full Text Available Aluminium based metal matrix composites have been produced from recycled aluminium cans and 150µm sized eggshell particles using a stir cast process. The mechanical properties of the control and aluminium can/eggshell composites produced have been investigated. The microstructures of the aluminium can/eggshell composites were examined with the aids of Scanning Electron Microscope (SEM after the sample surfaces have been carefully prepared and etched with aqueous solution of 0.5 cm3 nitric acid. Micrographs revealed that there was a homogenous distribution of eggshell particles within the aluminium can matrix. An indication of effective stirring action during the melting process. The wear resistance was also investigated under different applied loads (6 to 14 N on an abrasive surface emery paper of grade 220. The results revealed an increase in Young’s modulus of elasticity and yield stress from 1,206.45 and 50.23 Mpa respectively of the cast aluminium can with 0 % eggshell particle to the maximum of 3,258.87and 73.2 MPa of aluminium can/12 % eggshell composites. The hardness values increased from 66.23 to 75.13 VN. There was a gradual increase in wear rate of the tested samples as the applied load increased. However, the wear resistance of the aluminium can/6 % eggshell and aluminium can/12 % eggshell composites increased significantly. Hence, recycling of aluminium cans and eggshells can be harnessed into development of useful engineering metal matrix composite materials.

The Metal And Sulphate Removal From Mine Drainage Waters By Biological-Chemical Ways

Directory of Open Access Journals (Sweden)

Jenčárová Jana

2015-06-01

Full Text Available Mine drainage waters are often characterized by high concentrations of sulphates and metals as a consequence of the mining industry of sulphide minerals. The aims of this work are to prove some biological-chemical processes utilization for the mine drainage water treatment. The studied principles of contamination elimination from these waters include sulphate reduction and metal bioprecipitation by the application of sulphate-reducing bacteria (SRB. Other studied process was metal sorption by prepared biogenic sorbent. Mine drainage waters from Slovak localities Banská Štiavnica and Smolník were used to the pollution removal examination. In Banská Štiavnica water, sulphates decreased below the legislative limit. The elimination of zinc by sorption experiments achieved 84 % and 65 %, respectively.

Volcanic lake systems as terrestrial analogue for sulphate-rich terrains on Mars

NARCIS (Netherlands)

Rodríguez, A.

2016-01-01

Remote-sensing observations and rover missions have documented the abundant presence of sulphate-rich mineral associations on the surface of Mars. Together with widespread occurrences of silica and frequent enrichments of chlorine and bromine in soils and rocks, the sulphate associations are

Origin and nature of the aluminium phosphate-sulfate minerals (APS) associated with uranium mineralization in triassic red-beds (Iberian Range, Spain)

Energy Technology Data Exchange (ETDEWEB)

Marfil, R.; Iglesia, A. la; Estupinan, J.

2013-10-01

This study focuses on the mineralogical and chemical study of an Aluminium-phosphate-sulphate (APS) mineralization that occurs in a classic sequence from the Triassic (Buntsandstein) of the Iberian Range. The deposit is constituted by sandstones, mud stones, and conglomerates with arenaceous matrix, which were deposited in fluvial to shallow-marine environments. In addition to APS minerals, the following diagenetic minerals are present in the classic sequence: quartz, K-feldspar, kaolinite group minerals, illite, Fe-oxides-hydroxides, carbonate-sulphate cement-replacements and secondary uraniferous minerals. APS minerals were identified and characterized by optical microscopy, X-ray diffraction, scanning electron microscopy, and electron microprobe. Microcrystalline APS crystals occur replacing uraniferous minerals, associated with kaolinite, mica and filling pores, in distal fluvial-to-tidal arkoses-subarkoses. Given their Ca, Sr, and Ba contents, the APS minerals can be defined as a solid solution of crandallite- goyacite-gorceixite (0.53 Ca, 0.46 Sr and 0.01 Ba). The chemical composition, low LREE concentration and Sr > S suggest that the APS mineral were originated during the supergene alteration of the Buntsandstein sandstones due to the presence of the mineralizing fluids which causes the development of Ubearing sandstones in a distal alteration area precipitating from partially dissolved and altered detrital minerals. Besides, the occurrence of dickite associated with APS minerals indicates they were precipitated at diagenetic temperatures (higher than 80 degree centigrade), related to the uplifting occurred during the late Cretaceous post-rift thermal stage.(Author)

Origin and nature of the aluminium phosphate-sulfate minerals (APS) associated with uranium mineralization in triassic red-beds (Iberian Range, Spain)

International Nuclear Information System (INIS)

Marfil, R.; Iglesia, A. la; Estupinan, J.

2013-01-01

This study focuses on the mineralogical and chemical study of an Aluminium-phosphate-sulphate (APS) mineralization that occurs in a classic sequence from the Triassic (Buntsandstein) of the Iberian Range. The deposit is constituted by sandstones, mud stones, and conglomerates with arenaceous matrix, which were deposited in fluvial to shallow-marine environments. In addition to APS minerals, the following diagenetic minerals are present in the classic sequence: quartz, K-feldspar, kaolinite group minerals, illite, Fe-oxides-hydroxides, carbonate-sulphate cement-replacements and secondary uraniferous minerals. APS minerals were identified and characterized by optical microscopy, X-ray diffraction, scanning electron microscopy, and electron microprobe. Microcrystalline APS crystals occur replacing uraniferous minerals, associated with kaolinite, mica and filling pores, in distal fluvial-to-tidal arkoses-subarkoses. Given their Ca, Sr, and Ba contents, the APS minerals can be defined as a solid solution of crandallite- goyacite-gorceixite (0.53 Ca, 0.46 Sr and 0.01 Ba). The chemical composition, low LREE concentration and Sr > S suggest that the APS mineral were originated during the supergene alteration of the Buntsandstein sandstones due to the presence of the mineralizing fluids which causes the development of Ubearing sandstones in a distal alteration area precipitating from partially dissolved and altered detrital minerals. Besides, the occurrence of dickite associated with APS minerals indicates they were precipitated at diagenetic temperatures (higher than 80 degree centigrade), related to the uplifting occurred during the late Cretaceous post-rift thermal stage.(Author)

Surface roughness when diamond turning RSA 905 optical aluminium

Science.gov (United States)

Otieno, T.; Abou-El-Hossein, K.; Hsu, W. Y.; Cheng, Y. C.; Mkoko, Z.

2015-08-01

Ultra-high precision machining is used intensively in the photonics industry for the production of various optical components. Aluminium alloys have proven to be advantageous and are most commonly used over other materials to make various optical components. Recently, the increasing demand from optical systems for optical aluminium with consistent material properties has led to the development of newly modified grades of aluminium alloys produced by rapid solidification in the foundry process. These new aluminium grades are characterised by their finer microstructures and refined mechanical and physical properties. However the machining database of these new optical aluminium grades is limited and more research is still required to investigate their machinability performance when they are diamond turned in ultrahigh precision manufacturing environment. This work investigates the machinability of rapidly solidified aluminium RSA 905 by varying a number of diamond-turning cutting parameters and measuring the surface roughness over a cutting distance of 4 km. The machining parameters varied in this study were the cutting speed, feed rate and depth of cut. The results showed a common trend of decrease in surface roughness with increasing cutting distance. The lowest surface roughness Ra result obtained after 4 km in this study was 3.2 nm. This roughness values was achieved using a cutting speed of 1750 rpm, feed rate of 5 mm/min and depth of cut equal to 25 μm.

In vivo monitoring of skeletal aluminium burden in patients with renal failure

International Nuclear Information System (INIS)

Ellis, K.J.; Kelleher, S.; Raciti, A.; Savory, J.; Wills, M.

1988-01-01

In vivo neutron activation analysis was used to examine the total body and partial body (hand) aluminium levels in patients with end-stage renal failure. Patients maintained on chronic hemodialysis had higher mean body burdens of aluminium than did those clinically managed without dialysis. Approximately 70% of the patients examined indicated elevated levels of body or skeletal aluminium. A significant correlation was observed between the in vivo aluminium/calcium ratio obtained for the hand measurement and the increase in serum aluminium levels following a disferroxamine infusion test. The direct in vivo monitoring of hand Al/Ca values in patients may provide an alternate choice to bone biopsy for the detection of aluminium intoxication. (author) 15 refs.; 5 figs.; 2 tabs

Silicon Alloying On Aluminium Based Alloy Surface

International Nuclear Information System (INIS)

Suryanto

2002-01-01

Silicon alloying on surface of aluminium based alloy was carried out using electron beam. This is performed in order to enhance tribological properties of the alloy. Silicon is considered most important alloying element in aluminium alloy, particularly for tribological components. Prior to silicon alloying. aluminium substrate were painted with binder and silicon powder and dried in a furnace. Silicon alloying were carried out in a vacuum chamber. The Silicon alloyed materials were assessed using some techniques. The results show that silicon alloying formed a composite metal-non metal system in which silicon particles are dispersed in the alloyed layer. Silicon content in the alloyed layer is about 40% while in other place is only 10.5 %. The hardness of layer changes significantly. The wear properties of the alloying alloys increase. Silicon surface alloying also reduced the coefficient of friction for sliding against a hardened steel counter face, which could otherwise be higher because of the strong adhesion of aluminium to steel. The hardness of the silicon surface alloyed material dropped when it underwent a heating cycle similar to the ion coating process. Hence, silicon alloying is not a suitable choice for use as an intermediate layer for duplex treatment

Dietary exposure to aluminium of urban residents from cities in South China.

Science.gov (United States)

Jiang, Qi; Wang, Jing; Li, Min; Liang, Xuxia; Dai, Guangwei; Hu, Zhikun; Wen, Jian; Huang, Qiong; Zhang, Yonghui

2013-01-01

A dietary survey was conducted over three consecutive days by using 24-hour dietary recall in the Pearl River Delta of South China to investigate the dietary consumption status. A total of 1702 food samples, 22 food groups, were collected, and aluminium concentrations of foods were determined by using ICP-MS. Weekly dietary exposure to aluminium of the average urban residents of South China was estimated to be 1.5 mg kg⁻¹ body weight, which amounted to 76% of the provisional tolerable weekly intake. Wheat-made products (53.5%) contributed most to the dietary exposure, followed by vegetables (12.2%). The high-level consumers' weekly exposure to aluminium was 11.1 mg kg⁻¹ body weight, which amounted to 407% of the provisional tolerable weekly intake. The results indicated that the general urban residents in South China might be safe from aluminium exposure, but the high-level consumers might be at some risk of aluminium exposure. The foods contributing to aluminium exposure were processed food with aluminium-containing food additives. It is necessary to take effective measures to control the overuse of aluminium-containing food additives.

Usage of neural network to predict aluminium oxide layer thickness.

Science.gov (United States)

Michal, Peter; Vagaská, Alena; Gombár, Miroslav; Kmec, Ján; Spišák, Emil; Kučerka, Daniel

2015-01-01

This paper shows an influence of chemical composition of used electrolyte, such as amount of sulphuric acid in electrolyte, amount of aluminium cations in electrolyte and amount of oxalic acid in electrolyte, and operating parameters of process of anodic oxidation of aluminium such as the temperature of electrolyte, anodizing time, and voltage applied during anodizing process. The paper shows the influence of those parameters on the resulting thickness of aluminium oxide layer. The impact of these variables is shown by using central composite design of experiment for six factors (amount of sulphuric acid, amount of oxalic acid, amount of aluminium cations, electrolyte temperature, anodizing time, and applied voltage) and by usage of the cubic neural unit with Levenberg-Marquardt algorithm during the results evaluation. The paper also deals with current densities of 1 A · dm(-2) and 3 A · dm(-2) for creating aluminium oxide layer.

Usage of Neural Network to Predict Aluminium Oxide Layer Thickness

Directory of Open Access Journals (Sweden)

Peter Michal

2015-01-01

Full Text Available This paper shows an influence of chemical composition of used electrolyte, such as amount of sulphuric acid in electrolyte, amount of aluminium cations in electrolyte and amount of oxalic acid in electrolyte, and operating parameters of process of anodic oxidation of aluminium such as the temperature of electrolyte, anodizing time, and voltage applied during anodizing process. The paper shows the influence of those parameters on the resulting thickness of aluminium oxide layer. The impact of these variables is shown by using central composite design of experiment for six factors (amount of sulphuric acid, amount of oxalic acid, amount of aluminium cations, electrolyte temperature, anodizing time, and applied voltage and by usage of the cubic neural unit with Levenberg-Marquardt algorithm during the results evaluation. The paper also deals with current densities of 1 A·dm−2 and 3 A·dm−2 for creating aluminium oxide layer.

Treatment of pit water from uranium mining operation

International Nuclear Information System (INIS)

Mouton, A.; Lafforgue, P.; Lyaudet, G.

1984-01-01

The pit water from uranium mines is normally treated to eliminate the soluble radium and suspended solids. The radium is precipitated together with the barium sulphate. The latter results from the reaction of barium chloride with an excess of sulphate ions. The suspended solids are flocculated by aluminium salts (chloride, polychloride). If necessary, synthetic flocculants are also used. Certain grades of pit water contain, sometimes incidentally, a few milligrams of uranium per litre. These quantities always remain too low for any direct recovery (treatment by ion exchange resins). By applying certain measures, the preceding processes can also be used to eliminate uranium. The latter is carried away by aluminium hydroxide in a very narrow zone of pH (6 to 7,4) which corresponds to the minimum solubility of the hydroxide. Depending on the characteristic of the water (pH, salinity), use is made either of aluminium sulphate or of sodium aluminate, with an addition of a base in extreme cases. This article gives various examples of applications in the Haute-Vienne, Chardon in Vendee, the Commanderie mine in Vendee, at Cerilly in Allier and at Lodeve in Herault [fr

Elastic and plastic properties of iron-aluminium alloys. Special problems raised by the brittleness of alloys of high aluminium content; Proprietes elastiques et plastiques des alliages fer-aluminium. Problemes particuliers poses par la fragilite des alliages a forte teneur en aluminium

Energy Technology Data Exchange (ETDEWEB)

Mouturat, P. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1966-06-01

The present study embodies the results obtained with iron-aluminium alloys whose composition runs from 0 to nearly 50 atoms per cent aluminium. Conditions of elaboration and transformation have been studied successively, as well as the Young's modulus and the flow stress; the last chapter embodies, a study of the Portevin-le-Chatelier effect in alloys of 40 atoms per cent of aluminium. I) The principal difficulty to clear up consisted in the intergranular brittleness of ordered alloys; this brittleness has been considerably reduced with appropriate conditions of elaboration and transformation. II) The studies upon the Young's modulus are in connection with iron-aluminium alloys; transformation temperatures are well shown up. The formation of covalent bonds on and after 25 atoms per cent show the highest values of the modulus. III) The analysis of variations of the flow stress according to the temperature show some connection with ordered structures, the existence of antiphase domains and the existence of sur-structure dislocations. IV) In the ordered Fe Al domain the kinetics of the Portevin-le-Chatelier effect could be explained by a mechanism of diffusion of vacancies. The role they play has been specified by the influence they exert upon the dislocations; this has led us to the inhomogeneous Rudman order; this inhomogeneous order could explain the shape of the traction curves. (author) [French] Cette etude comporte les resultats obtenus avec des alliages fer-aluminium dont la composition s'etend de 0 a pres de 50 atomes pour cent d'aluminium. Nous avons etudie successivement les conditions d'elaboration et de transformation, le module elastique et la limite elastique; un dernier chapitre est consacre a l'etude du phenomene Portevin-le-Chatelier dans les alliages a 40 atomes pour cent d'aluminium. I) La principale difficulte a resoudre residait dans la fragilite intergranulaire des alliages ordonnes; celle-ci a ete

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

Science.gov (United States)

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

2013-10-01

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

Abiotic nitrate and sulphate reduction by hydrogen: a comparative experimental study

International Nuclear Information System (INIS)

Truche, L.; Berger, G.; Albrecht, A.; Giffaut, E.

2010-01-01

Document available in extended abstract form only. The bituminous waste which is part of the intermediate level, long-lived waste (MAVL) is characterised, amongst others, by the coexistence of nitrates, sulphates, organic matter, native metals and hydrogen gas in the waste mixture and package. It can be considered as the most complex example that will be used to discuss redox reactions occurring in such waste mixtures. The evaluation of the redox conditions requires quantification of the amount of electron acceptors and donors and definition of the kinetics of redox reaction. The objectives of an experimental study to unravel some of these reaction complexities are: - to investigate nature and rate of sulphate and nitrate reduction by hydrogen in the presence of different catalysts (stainless steel, hastelloy, magnetite and argillite); - to compare sulphate and nitrate as electron acceptors; - to provide a mechanistic model of these reactions. It is well known that reduction of sulphate and nitrate requires high activation energies, usually supplied either by thermal processes or via bacterial and surface catalysis, of which the latter has been investigated in this study. Preliminary experiments performed at 150 deg. C and under H 2 pressure show that sulphate reduction is enhanced in the presence of magnetite, but essentially under the restricted condition of low sulphate concentration and at a pH below the Point of Zero Charge of magnetite. This suggests that sorption of sulphate contributes to the catalysed reaction (at low pH) but provided that the magnetite surface sites are not saturated with respect to aqueous sulphate (low concentration). On the contrary, nitrate reduction is observed whatever the pH and the nitrate concentration in the presence of both magnetite and hastelloy C276 (Ni, Cr, Mo, W, Fe alloy). The effect of temperature on the rate of nitrate reduction (500 ppm KNO 3 solution) is shown by comparing three different experiments conducted in

Potentiometric titration curves of aluminium salt solutions and its ...

African Journals Online (AJOL)

Potentiometric titration curves of aluminium salt solutions and its species conversion ... of aluminium salt solutions under the moderate slow rate of base injection. ... silicate radical, and organic acid radical on the titration curves and its critical ...

Bioaccumulation of Aluminium in Hydromacrophytes in Polish Coastal Lakes

Directory of Open Access Journals (Sweden)

Senze Magdalena

2015-03-01

Full Text Available The research on aluminium content was conducted in water and on aquatic flora of Polish lakes in the central part of the coast. The study included the lakes Sarbsko, Choczewskie, Bia.e, K.odno, D.brze and Salino investigated in the summer of 2013. The examined lakes belong mainly to the direct basin of the Baltic Sea. Samples of aquatic plants and lake waters were collected. In the water samples pH and electrolytic conductivity were measured. The aluminium content was determined both in water and aquatic plants. Submerged hydromacrophyte studies included Myriophyllum alterniflorum L., Potamogeton perfoliatus L. and Ceratophyllum demersum L. Emergent hydromacrophyte studies included Phragmites australis (Cav. Trin. ex Steud., Juncus bulbosus L., Iris pseudacorus L., Eleocharis palustris (L. Roem. % Schult., Phalaris arundinacea L., Carex riparia Curt., Mentha aquatic L., Stratiotes aloides L., Alisma plantago-aquatica L., Glyceria maxima (Hartman Holmb., Sagittaria sagittifolia L., Scirpus lacustris L. and Typha angustifolia L. The purpose of this investigation was the determination of the aluminium content in submerged and emergent hydromacrophytes and also the definition of their bioaccumulative abilities. The average concentration of aluminium in water was 2.68 fęg Al dm.3. The average content of aluminium in plants was 2.8015 mg Al kg.1. The bioaccumulation factor ranged from BCF=19.74 to BCF=16619. On the basis of the analysis of the aluminium content in water and aquatic plants results show that both water and plants were characterized by a moderate level of aluminium. The recorded concentrations indicate a mid-range value and are much lower than those which are quoted for a variety of surface waters in various parts of the world.

Lake restoration with aluminium, bentonite and Phoslock: the effect on sediment stability and light attenuation

DEFF Research Database (Denmark)

Egemose, Sara; Reitzel, Kasper; Flindt, Mogens

treatments on aluminium mobility, sediment stability or light climate. A laboratory flume experiment including three shallow Danish lakes was conducted. We measured the effects of aluminium, Phoslock (a commercial product), bentonite, and a combination of bentonite/aluminium. Each treatment caused a varying...... consolidation of the sediment. The largest consolidation occurred using Phoslock- and bentonite-addition followed by bentonite/aluminium-addition, whereas aluminium alone had no effect. Sediment stability thresholds were measured before and after addition. Especially Phoslock, but also bentonite and bentonite....../aluminium increased sediment erosion threshold, with respectively 200%, 43% and 57%. Aluminium, bentonite/aluminium, and Phoslock improved the light conditions in the water phase, with respectively 60%, 57% and 50%, whereas bentonite created higher turbidity. Conclusively aluminium improved the light conditions...

Anodization of Aluminium using a fast two-step process

Indian Academy of Sciences (India)

283.6 eV. Keywords. Anodization; phosphoric acid; anodization time; anodized aluminium oxide; aluminium. ... of anodization.5–7 The AAO layer has a large band gap, good ..... transmittance increases as the anodised membrane is heated to ...

Serum aluminium levels in glue-sniffer adolescent and in glue containers.

Science.gov (United States)

Akay, Cemal; Kalman, Süleyman; Dündaröz, Ruşen; Sayal, Ahmet; Aydin, Ahmet; Ozkan, Yalçin; Gül, Hüsamettin

2008-05-01

Glue sniffing is a serious medical problem among teenagers. Various chemical substances such as toluene and benzene containing glues have been reported to be toxic. It has been demonstrated that some toxic metals such as lead are elevated in the blood of solvent-addicted patients. Whereas aluminium is an element that has toxic effects on neurological, hematopoetic system and bone metabolism. We want to determine the serum levels of aluminium in glue-sniffer adolescents in comparison with healthy subjects. In addition, we compared aluminium levels of different commercial glue preparations (i.e. metal and plastic containers), to determine which type of container is better for less aluminium toxicity. We measured serum levels of aluminium in 37 glue-sniffer and 37 healthy subjects using atomic absorption spectrophotometry. The average duration of glue-sniffer was 3.8 +/- 0.8 years. We also measured aluminium levels of 10 commercial glue preparations that seven of them with metal and three with plastic containers. We found that serum levels of aluminium were 63.29 +/- 13.20 ng/ml and 36.7 +/- 8.60 ng/ml in glue-sniffer and in control subjects, respectively (P sniffers, it may be a good step to market of glue preparations in plastic instead of metal containers.

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

Science.gov (United States)

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

2015-01-01

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

Deposition of aluminium nanoparticles using dense plasma focus device

International Nuclear Information System (INIS)

Devi, Naorem Bilasini; Srivastava, M P; Roy, Savita

2010-01-01

Plasma route to nanofabrication has drawn much attention recently. The dense plasma focus (DPF) device is used for depositing aluminium nanoparticles on n-type Si (111) wafer. The plasma chamber is filled with argon gas and evacuated at a pressure of 80 Pa. The substrate is placed at distances 4.0 cm, 5.0 cm and 6.0 cm from the top of the central anode. The aluminium is deposited on Si wafer at room temperature with two focused DPF shots. The deposits on the substrate are examined for their morphological properties using atomic force microscopy (AFM). The AFM images have shown the formation of aluminium nanoparticles. From the AFM images, it is found that the size of aluminium nanoparticles increases with increase in distance between the top of anode and the substrate for same number of DPF shots.

Effect of Ethylenediaminetetraacetic Acid and Ammonium Oxalate ...

African Journals Online (AJOL)

ADOWIE PERE

acid and ammonium oxalate on the prevalence of microorganisms and removal of aluminum in soil by bitter leaf plant (Vernonia ... highest accumulation of aluminium in the root (16.92mg/kg); however concentrations of aluminium in the roots were .... whereas the sulphate was 13.75mg/kg. Table 2: The total colony count of ...

Corrosion issues of powder coated AA6060 aluminium profiles

DEFF Research Database (Denmark)

Din, Rameez Ud; Valgarðsson, Smári; Jellesen, Morten Stendahl

2015-01-01

In this study detailed microstructural investigation of the reason for unexpected corrosion of powder coated aluminium alloy AA6060 windows profiles has been performed. The results from this study reveals that the failure of the window profiles was originated from the surface defects present...... on the extruded AA6060 aluminium profile after metallurgical process prior to powder coating. Surface defects are produced due to intermetallic particles in the alloy, which disturb the flow during the extrusion process. The corrosion mechanism leading to the failure of the powder coated AA6060 aluminium profiles...

Sulphate content of the Muntimpa dam water and its impact on water quality

International Nuclear Information System (INIS)

Tembo, F; Shitumbanuma, V; Simukanga, S; Mudenda, G; Chileshe, P; Mulenga, S; Phiri, Y

2004-01-01

This article presents results of a study of the quality of water from Muntimpa Dam, a reservior of waste mine water released from the processing of copper and cobalt ores by Konkola Copper Mines(KCM) Plc in Chingola. The mine water is discharged into the local Muntimpa stream, a possible source of drinking and domestic water for the local population. The purpose of the study was to determine levels of sulphate in the dam and stream water and recommend possible methods of partial sulphate removal to levels below the recommended statutory limits and secondly, to assess the impact of high sulphate levels on water quality. Study methods included the sampling of water from the Muntimpa dam and catchment area. Stream water samples were collected about 5m from the stream banks while water samples from the dam were randomly collected from the near the centre of the dam at a depth of 50cm. Laboratory methods involved the determination of physical and chemical properties of the water using standard analytical techniques. Results of the study indicate that both total (2470mg/l) and available (1965mg/l) sulphate concentrations are higher than the recommended statutory limit for the discharge of sulphates into natural streams of 1500mg/l. From the study it is concluded that water in Muntimpa dam and stream is not suitable for drinking and other domestic use due to the high sulphate levels. From theorectical considerations, it was established that sulphate reduction could be achieved by addition of lime, which however had the consquence of increasing the pH of the water in excess of the recommended Zambian statutory value of nine, and would thus require an additional process to reduce the pH. (author)

Grass-cellulose as energy source for biological sulphate removal from acid mine effluents

CSIR Research Space (South Africa)

Greben, HA

2008-11-01

Full Text Available The biological sulphate removal technology requires carbon and energy sources to reduce sulphate to sulphide. Plant biomass, e.g. grass, is a sustainable source of energy when cellulose is utilised during anaerobic degradation, producing volatile...

Aluminium tolerance in rice is antagonistic with nitrate preference and synergistic with ammonium preference.

Science.gov (United States)

Zhao, Xue Qiang; Guo, Shi Wei; Shinmachi, Fumie; Sunairi, Michio; Noguchi, Akira; Hasegawa, Isao; Shen, Ren Fang

2013-01-01

Acidic soils are dominated chemically by more ammonium and more available, so more potentially toxic, aluminium compared with neutral to calcareous soils, which are characterized by more nitrate and less available, so less toxic, aluminium. However, it is not known whether aluminium tolerance and nitrogen source preference are linked in plants. This question was investigated by comparing the responses of 30 rice (Oryza sativa) varieties (15 subsp. japonica cultivars and 15 subsp. indica cultivars) to aluminium, various ammonium/nitrate ratios and their combinations under acidic solution conditions. indica rice plants were generally found to be aluminium-sensitive and nitrate-preferring, while japonica cultivars were aluminium-tolerant and relatively ammonium-preferring. Aluminium tolerance of different rice varieties was significantly negatively correlated with their nitrate preference. Furthermore, aluminium enhanced ammonium-fed rice growth but inhibited nitrate-fed rice growth. The results suggest that aluminium tolerance in rice is antagonistic with nitrate preference and synergistic with ammonium preference under acidic solution conditions. A schematic diagram summarizing the interactions of aluminium and nitrogen in soil-plant ecosystems is presented and provides a new basis for the integrated management of acidic soils.

Synthesis, properties, and assimilation methods of aluminium hydride

International Nuclear Information System (INIS)

Mirsaidov, U.M.

2013-01-01

We have discovered a new source of aluminium hydride-conversion of tetrahydrofurane under influence of halogenous alkyls. We have proposed the chlorbenzene method of synthesis of AlH 3 , which excludes adhesion and ensure high quality of the product with respect to its purity, thermal stability, habits of crystals (round shape), and granulometric composition. We determined capability of benzyl chloride to fix AlH 4 -groups by the way of complexes formation. This allows increasing efficient concentration of AlH 3 solutions and their productivity. We have carried out 'direct' crystallization of aluminium hydride in one stage using interaction of binary metal hydride with aluminium chloride in the medium of ether-toluene at 60-100 d ig C a nd using solvent distillation. In the reaction of Li H with AlCl 3 , we achieved output of pure crystal AlH 3 of hexagonal modification, which was close to quantitative. We have discovered the assimilation methods of aluminium hydride in carrying out of solid-phase chemical reactions. (author)

Development of a glass matrix for vitrification of sulphate bearing high level radioactive liquid waste

International Nuclear Information System (INIS)

Kaushik, C.P.; Mishra, R.K.; Thorat, Vidya; Ramchandran, M.; Amar Kumar; Ozarde, P.D.; Raj, Kanwar; Das, D.

2004-07-01

High level radioactive liquid waste (HLW) is generated during reprocessing of spent nuclear fuel. In the earlier reprocessing flow sheet ferrous sulphamate has been used for valancy adjustment of Pu from IV to III for effective separation. This has resulted in generation of HLW containing significance amount of sulphate. Internationally borosilicate glass matrix has been adopted for vitrification of HLW. The first Indian vitrification facility at Waste Immobilislition Plant (WIP), Tarapur a five component borosilicate matrix (SiO 2 :B 2 O 3 :Na 2 O : MnO : TiO 2 ) has been used for vitrification of waste. However at Trombay HLW contain significant amount of sulphate which is not compatible with standard borosilicate formulation. Extensive R and D efforts were made to develop a glass formulation which can accommodate sulphate and other constituents of HLW e.g., U, Al, Ca, etc. This report deals with development work of a glass formulations for immobilization of sulphate bearing waste. Different glass formulations were studied to evaluate the compatibility with respect to sulphate and other constituents as mentioned above. This includes sodium, lead and barium borosilicate glass matrices. Problems encountered in different glass matrices for containment of sulphate have also been addressed. A glass formulation based on barium borosilicate was found to be effective and compatible for sulphate bearing high level waste. (author)

Indentation of aluminium foam at low velocity

Directory of Open Access Journals (Sweden)

Shi Xiaopeng

2015-01-01

Full Text Available The indentation behaviour of aluminium foams at low velocity (10 m/s ∼ 30 m/s was investigated both in experiments and numerical simulation in this paper. A flat-ended indenter was used and the force-displacement history was recorded. The Split Hopkinson Pressure bar was used to obtain the indentation velocity and forces in the dynamic experiments. Because of the low strength of the aluminium foam, PMMA bar was used, and the experimental data were corrected using Bacon's method. The energy absorption characteristics varying with impact velocity were then obtained. It was found that the energy absorption ability of aluminium foam gradually increases in the quasi-static regime and shows a significant increase at ∼10 m/s velocity. Numerical simulation was also conducted to investigate this process. A 3D Voronoi model was used and models with different relative densities were investigated as well as those with different failure strain. The indentation energy increases with both the relative density and failure strain. The analysis of the FE model implies that the significant change in energy absorption ability of aluminium foam in indentation at ∼10 m/s velocity may be caused by plastic wave effect.

Improvement of photodynamic activity of aluminium sulphophthalocyanine due to biotinylation

Science.gov (United States)

Meerovich, Irina G.; Jerdeva, Victoria V.; Derkacheva, Valentina M.; Meerovich, Gennadii A.; Lukyanets, Eugeny A.; Kogan, Eugenia A.; Savitsky, Alexander P.

2003-09-01

The photodynamic activity of dibiotinylated aluminium sulphophthalocyanine in vitro and in vivo were studied. It was obtained that in vitro dibiotinylated aluminium sulphophthalocyanine provides the effective damage of small cell lung carcinoma OAT-75. In vivo dibiotinylated aluminium sulphophthalocyanine causes destruction of tumor (Erlich carcinoma), results in total necrosis of tumor tissue and expresses vascular damage (trombosis and destruction of vascular walls) even in concentration 0.25 mg/kg of a body weight.

Aluminium supplier selection for the automotive parts manufacturer

Directory of Open Access Journals (Sweden)

M. Cieśla

2016-04-01

Full Text Available This paper presents a methodology for selection of the optimal sources of supply, which is also known as the problem of supplier selection. Theoretical considerations are expanded with research related to aluminium supplier selection for a hypothetical manufacturer of aluminium parts for transportation equipment located in Poland. Evaluation of five suppliers of aluminium from Poland, Germany and Slovenia has been conducted using a weighted scoring method, a strengths and weaknesses method and a graphical method. Choosing the best offer and prioritizing suppliers allows not only the most rational decision in the field of supply logistics to be taken but also the quality of service in the metallurgical industry to be improved.

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

Science.gov (United States)

Mudge, David W; Johnson, David W; Hawley, Carmel M; Campbell, Scott B; Isbel, Nicole M; van Eps, Carolyn L; Petrie, James J B

2011-05-13

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

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

Directory of Open Access Journals (Sweden)

van Eps Carolyn L

2011-05-01

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

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

Science.gov (United States)

2011-01-01

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

Decomposition of pre calcined aluminium silicate ores of Afghanistan by hydrochloric acid

International Nuclear Information System (INIS)

Khomidi, A.K.; Mamatov, E.D.

2015-01-01

Present article is devoted to decomposition of pre calcined aluminium silicate ores of Afghanistan by hydrochloric acid. The physicochemical properties of initial aluminium silicate ores were studied by means of X-ray phase, differential thermal and silicate analysis. The chemical composition of aluminium containing ores was determined. The optimal conditions of interaction of initial and pre calcined siallites with hydrochloric acid were defined. The kinetics of acid decomposition of aluminium silicate ores was studied as well.

An interesting and efficient green corrosion inhibitor for aluminium ...

African Journals Online (AJOL)

An interesting and efficient green corrosion inhibitor for aluminium from extracts of ... Journal Home > Vol 13, No 1 (2014) > ... possible applications in metal surface anodizing and surface coating in industries. Keywords: Moringa oleifera, Aluminium, Hydrochloric acid, Langmuir isotherm, Plant extracts, Corrosion inhibition ...

Power distribution: conductors in aluminium

International Nuclear Information System (INIS)

Schmid, R.

2007-01-01

This article takes a look at the use of aluminium conductors in medium and low-voltage cables. The author discusses how the increasing price of copper has led to the increasing use of aluminium as a material for the production of the conductors used in medium and low-voltage power cables. Aid is provided that is to help purchasers make the correct decisions when buying medium and low-voltage cables. The current market situation is examined and the appropriate norms are looked at. Technical data and economic aspects are discussed, both for medium and low-voltage applications. The electrical characteristics of the type of cable to be used are examined and discussed

Spectrographic determination of trace impurities in reactor grade aluminium

International Nuclear Information System (INIS)

Chandola, L.C.; Machado, I.J.

1975-01-01

A spectrographic method enabling the determination of 21 trace impurities in aluminium oxide is described. The technique involves mixing the sample with graphite buffer in the ratio 1:1, loading it in a graphite electrode and arcing it for 30 sec. in a dc arc to 10 A current against a pointed graphite cathode. The spectra are photographed on Ilford N.30 emulsion employing a large quartz spectrograph. The aluminium line at 2669.2 A 0 serves as the internal standard. The impurities determined are Ag, B, Bi, Cd, Co, Cr, Cu, Fe, Ga, In, Mg, Mo, Ni, Pb, Sb, Si, Sn, Ti, V and Zn. The sensitivity varies from 5 to 100 ppm and the precision from +- 5 to +- 22% for different elements. A method for converting aluminium metal to aluminium oxide is described. It is found that boron is not lost during this conversion. (author)

Friction and corrosion resistance of sputter deposited supersaturated metastable aluminium-molybdenum alloys

Energy Technology Data Exchange (ETDEWEB)

Abu-Zeid, O.A. [Univ. of the United Arab Emirates, Al-Ain (United Arab Emirates). Dept. of Mech. Eng.; Bates, R.I. [Design, Mfg. and Marketing Research Inst., Univ. of Salford (United Kingdom)

1996-12-15

Two closed field unbalanced magnetrons with targets of aluminium and molybdenum have been used for the co-deposition of aluminium-molybdenum coatings with different compositions. A pin on disk machine and a computer controlled potentiostat have been used to evaluate respectively, the tribological and corrosion properties of the deposited alloys. Results have shown that introducing molybdenum into aluminium coatings improves their poor tribological properties. Aluminium-molybdenum coatings with different compositions have shown low wear behaviour and for coatings with high molybdenum contents (> 80%) friction coefficients against steel, as low as 0.18 have been obtained. The addition of molybdenum into aluminium coatings has reduced their corrosion tendency and corrosion current density in a marine environment. (orig.)

Towards toxicokinetic modelling of aluminium exposure from adjuvants in medicinal products.

Science.gov (United States)

Weisser, Karin; Stübler, Sabine; Matheis, Walter; Huisinga, Wilhelm

2017-08-01

As a potentially toxic agent on nervous system and bone, the safety of aluminium exposure from adjuvants in vaccines and subcutaneous immune therapy (SCIT) products has to be continuously re-evaluated, especially regarding concomitant administrations. For this purpose, knowledge on absorption and disposition of aluminium in plasma and tissues is essential. Pharmacokinetic data after vaccination in humans, however, are not available, and for methodological and ethical reasons difficult to obtain. To overcome these limitations, we discuss the possibility of an in vitro-in silico approach combining a toxicokinetic model for aluminium disposition with biorelevant kinetic absorption parameters from adjuvants. We critically review available kinetic aluminium-26 data for model building and, on the basis of a reparameterized toxicokinetic model (Nolte et al., 2001), we identify main modelling gaps. The potential of in vitro dissolution experiments for the prediction of intramuscular absorption kinetics of aluminium after vaccination is explored. It becomes apparent that there is need for detailed in vitro dissolution and in vivo absorption data to establish an in vitro-in vivo correlation (IVIVC) for aluminium adjuvants. We conclude that a combination of new experimental data and further refinement of the Nolte model has the potential to fill a gap in aluminium risk assessment. Copyright © 2017 Elsevier Inc. All rights reserved.

RESPONSE OF PHENOLIC METABOLISM INDUCED BY ALUMINIUM TOXICITY IN FAGOPYRUM ESCULENTUM MOENCH. PLANTS.

Science.gov (United States)

Smirnov, O E; Kosyan, A M; Kosyk, O I; Taran, N Yu

2015-01-01

Buckwheat genus (Fagopyrum Mill.) is one of the aluminium tolerant taxonomic units of plants. The aim of the study was an evaluation of the aluminium (50 μM effect on phenolic accumulation in various parts of buckwheat plants (Fagopyrum esculentum Moench). Detection of increasing of total phenolic content, changes in flavonoid and anthocyanin content and phenylalanine ammonia-lyase activity (PAL) were revealed over a period of 10 days of exposure to aluminium. The most significant effects of aluminium treatment on phenolic compounds accumulation were total phenolic content increasing (by 27.2%) and PAL activity rising by 2.5 times observed in leaves tissues. Received data could be helpful to understand the aluminium tolerance principles and relationships of phenolic compounds to aluminium phytotoxicity.

Treatment of acid and sulphate-rich effluents in an integrated biological/chemical process

CSIR Research Space (South Africa)

Maree, JP

2004-04-01

Full Text Available .4 g SO4/(l.d). The rate of biological sulphate removal was found to be directly related to the square root of sulphate, COD and VSS concentrations respectively, and inversely proportional to sulphide concentration. The practical value of simultaneous...

Comparison of the effects of the K(+)-channel openers cromakalim and minoxidil sulphate on vascular smooth muscle.

Science.gov (United States)

Wickenden, A. D.; Grimwood, S.; Grant, T. L.; Todd, M. H.

1991-01-01

1 The actions of the potassium channel openers, cromakalim and minoxidil sulphate, were compared in a range of isolated blood vessel preparations. 2 Cromakalim and minoxidil sulphate inhibited spontaneous mechanical activity of the guinea-pig portal vein and relaxed the noradrenaline precontracted rat aorta with similar potency. In contrast, minoxidil sulphate was less potent than cromakalim in inhibiting spontaneous activity in the rat portal vein and was essentially inactive in the noradrenaline precontracted rat mesenteric artery and rabbit aorta. 3 Minoxidil sulphate did not antagonize the effects of cromakalim in the rabbit aorta indicating it was not acting as a partial 'agonist'. 4 Charybdotoxin, noxiustoxin and rubidium failed to discriminate between cromakalim and minoxidil sulphate indicating that the apparently selective effects of minoxidil sulphate were not mediated by either Ca(2+)-activated potassium channels, delayed rectifiers or rubidium impermeable potassium channels. 5 Glibenclamide antagonized the effects of cromakalim in an apparently competitive manner whereas the effects of minoxidil sulphate were antagonized in a non-competitive manner. The involvement of subtypes of ATP-sensitive potassium channels is discussed. PMID:1878752

Modelling of heterogeneous clustering in aluminium

International Nuclear Information System (INIS)

Smith, A.E.; Bourgeois, L.; Nie, J.-F.; Muddle, B.C.

2003-01-01

Full text: Ab initio modelling of heterogeneous clustering in aluminium has been carried out in order to study the precipitation hardening of alloys. This process is based on the addition of small amounts of solute element to the pure metal. With increasing computational power, atomic scale effects can now be better simulated to determine the nature of the hardening mechanism. Comparisons are made between results obtained from two computational packages. These are the Linear Augmented Plane Wave WEEN2K and the plane wave pseudopotential density functional theory package fhi98md. The study of the optimal geometry of very small size clusters inside aluminium has begun with the testing of initial convergence conditions by determination of binding energies for a variety of super cell sizes of the aluminium host crystal. These are compared with total energy calculations for small size precipitates of copper and transition metals of fixed geometry. Such local optimal determinations are seen as precursors to full Monte Carlo calculations of the notional best local geometry for larger precipitates

Sodium Sulphate Effect on Cement Produced with Building Stone Waste

Directory of Open Access Journals (Sweden)

Emre Sancak

2015-01-01

Full Text Available In this study, the blended cements produced by using the building stone waste were exposed to sulphate solution and the cement properties were examined. Prepared mortar specimens were cured under water for 28 days and then they were exposed to three different proportions of sodium sulphate solution for 125 days. Performances of cements were determined by means of compressive strength and tensile strength tests. The broken parts of some mortar bars were examined with scanning electron microscope (SEM. Besides, they were left under moist atmosphere and their length change was measured and continuously monitored for period of 125 days. In blended cements, solely cements obtained by replacing 10–20% of diatomites gave similar strength values with ordinary Portland cement (CEM I 42.5R at the ages of 7, 28, and 56 days. In all mortar specimens that included either waste andesite (AP or marble powder (MP showed best performance against very severe effective sodium sulphate solutions (13500 mg/L.

Synthesis of aluminium nanoparticles by arc evaporation of an ...

Indian Academy of Sciences (India)

Administrator

Abstract. Aluminium nanoparticles (Al Nps) are synthesized using arc discharge method by applying direct current between aluminium electrodes in liquid environment without any use of vacuum equipment, heat exchangers, high temperatures furnaces and inert gases. After synthesis of Al Nps, in situ coating process on.

The varied functions of aluminium-activated malate transporters–much more than aluminium resistance

Science.gov (United States)

Palmer, Antony J.; Baker, Alison; Muench, Stephen P.

2016-01-01

The ALMT (aluminium-activated malate transporter) family comprises a functionally diverse but structurally similar group of ion channels. They are found ubiquitously in plant species, expressed throughout different tissues, and located in either the plasma membrane or tonoplast. The first family member identified was TaALMT1, discovered in wheat root tips, which was found to be involved in aluminium resistance by means of malate exudation into the soil. However, since this discovery other family members have been shown to have many other functions such as roles in stomatal opening, general anionic homoeostasis, and in economically valuable traits such as fruit flavour. Recent evidence has also shown that ALMT proteins can act as key molecular actors in GABA (γ-aminobutyric acid) signalling, the first evidence that GABA can act as a signal transducer in plants. PMID:27284052

Should Magnesium Sulphate Prophylaxis be Used in all Cases of Severe Preeclampsia?

Directory of Open Access Journals (Sweden)

Sohini Bhattacharya,

2011-01-01

Full Text Available A case control study, undertaken in the department of Obstetrics and Gynecology in a tertiary referral centre, was designed to administer standard dose of magnesium sulphate to 50 randomly selected severely preeclamptic women in labor (Group 1. 48 women who formed the control group did not receive the drug (Group 2. The admission – delivery interval, rate of Cesarean section showed no statistically significant difference. Four patients developed convulsions in Group 1 in contrast to twelve patients in Group 2. Efficacy of magnesium sulphate at preventing eclampsia was calculated as 68%. Mild respiratory depression occurred in two cases and oliguria in eight cases in Group 1. Both the conditions improved on suspending further doses of magnesium sulphate. No patient had post partum haemorrhage in Group 1 although 4% patients had it in Group 2. Neonatal outcome was comparable in both the groups. Hence magnesium sulphate may be regarded as a fairly safe and effective prophylactic agent for eclampsia when used in severe preeclampsia in labor.

Thermal decomposition of hydrotalcite with chromate, molybdate or sulphate in the interlayer

Energy Technology Data Exchange (ETDEWEB)

Frost, Ray L. [Inorganic Materials Research Program, School of Physical and Chemical Sciences, Queensland University of Technology, GPO Box 2434, Brisbane Queensland 4001 (Australia)]. E-mail: r.frost@qut.edu.au; Musumeci, Anthony W. [Inorganic Materials Research Program, School of Physical and Chemical Sciences, Queensland University of Technology, GPO Box 2434, Brisbane Queensland 4001 (Australia); Bostrom, Thor [Inorganic Materials Research Program, School of Physical and Chemical Sciences, Queensland University of Technology, GPO Box 2434, Brisbane Queensland 4001 (Australia); Adebajo, Moses O. [Inorganic Materials Research Program, School of Physical and Chemical Sciences, Queensland University of Technology, GPO Box 2434, Brisbane Queensland 4001 (Australia); Weier, Matt L. [Inorganic Materials Research Program, School of Physical and Chemical Sciences, Queensland University of Technology, GPO Box 2434, Brisbane Queensland 4001 (Australia); Martens, Wayde [Inorganic Materials Research Program, School of Physical and Chemical Sciences, Queensland University of Technology, GPO Box 2434, Brisbane Queensland 4001 (Australia)

2005-05-15

The thermal decomposition of hydrotalcites with chromate, molybdate and sulphate in the interlayer has been studied using thermogravimetric analysis coupled to a mass spectrometer measuring the gas evolution. X-ray diffraction shows the hydrotalcites have a d(0 0 3) spacing of 7.98 A with very small differences in the d-spacing between the three hydrotalcites. XRD was also used to determine the products of the thermal decomposition. For the sulphate-hydrotalcite decomposition the products were MgO and a spinel MgAl{sub 2}O{sub 4}, for the chromate interlayered hydrotalcite MgO, Cr{sub 2}O{sub 3} and spinel. For the molybdate interlayered hydrotalcite the products were MgO, spinel and MgMoO{sub 4}. EDX analyses enabled the formula of the hydrotalcites to be determined. Two processes are observed in the thermal decomposition namely dehydration and dehydroxylation and for the case of the sulphate interlayered hydrotalcite, a third process is the loss of sulphate. Both the dehydration and dehydroxylation take place in three steps each for each of the hydrotalcites.

Computer modelling of age hardening for cast aluminium alloys

International Nuclear Information System (INIS)

Wu, Linda; Ferguson, W George

2009-01-01

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

Light-weight aluminium bridges and bridge decks. An overview of recent applications

NARCIS (Netherlands)

Maljaars, J.; Soetens, F.; Kluyver, D. de

2008-01-01

The last decades have shown a large increase in the application of aluminium alloys for light-weight bridges. For bridge construction, aluminium alloys have some specific advantages, but also some points of attention. This paper deals with some recent projects of aluminium bridges, and for these

Improving the wettability of 2024 aluminium alloy by means of cold plasma treatment

Science.gov (United States)

Polini, W.; Sorrentino, L.

2003-05-01

Aluminium alloys are heavily used to manufacture structural parts in the aeronautic industry because of its lightness and its corrosion resistance. These alloys are successfully used in other industrial fields too, such as railway, automotive and naval industries. The need to contrast the severe use conditions and the heavy stresses developing in aeronautic field implies to protect the surfaces of the structures in aluminium alloy by any deterioration. To preserve by deterioration, it is necessary to make aluminium more suitable to be coated by protective paint. In the aeronautic industry, a complex and critical process is used in order to enhance both wettability and adhesive properties of aluminium alloy surfaces. Cold plasma treatment represents an efficient, clean and economic alternative to activate aluminium surfaces. The present work deals with air cold plasma treatment of 2024 aluminium alloy surfaces. The influence of dc electrical discharge cold plasma parameters on wettability of 2024 aluminium alloy surfaces has been studied. A set of process variables (voltage, time and air flow rate) has been identified and used to conduct some experimental tests on the basis of design of experiment (DOE) techniques. The experimental results show that the proposed plasma process may considerably increase aluminium alloy wettability. These results represent the first step in trying to optimise the aluminium adhesion by means of this non-conventional manufacturing process.

Effect of iron and silicon in aluminium and its alloys

International Nuclear Information System (INIS)

Kovacs, I.

1990-01-01

The iron and silicon are the main impurities in aluminium, they are always present in alloys made from commercially pure base material. The solid solubility of iron in aluminium is very low, therefore its largest amount forms intermetallic compounds the kind of which depends strongly on the other impurities of alloying elements. Although the solid solubility of silicon is much larger than that of the iron, it is the constituent of both the primary and the secondary particles, the structure of which depends in general on the iron-silicon concentration ratio. These Fe and Si containing particles can cause various and basic changes in the macroscopic properties of the alloy. Since commercially pure aluminium has extensive consumer and industrial use, it is very important to know, not only from scientific but also from practical point of view, the effect of iron and silicon on the physical and mechanical properties of aluminium and its alloys. The aim of the ''International Workshop on the Effect of Iron and Silicon in Aluminium and its Alloys'' was to clarify the present knowledge on this subject. The thirty papers presented at the Workshop and collected in this Proceedings cover many important fields of the subject. I hope that they will contribute to both the deeper understanding of the related phenomena and the improvement of technologies for producing better aluminium alloys

Microstructure and properties of aluminium-aluminium oxide graded composite materials

Science.gov (United States)

Kamaruzaman, F. F.; Nuruzzaman, D. M.; Ismail, N. M.; Hamedon, Z.; Iqbal, A. K. M. A.; Azhari, A.

2018-03-01

In this research works, four-layered aluminium-aluminium oxide (Al-Al2O3) graded composite materials were fabricated using powder metallurgy (PM) method. In processing, metal-ceramic graded composite materials of 0%, 10%, 20% and 30% weight percentage of ceramic concentration were prepared under 30 ton compaction load using a cylindrical die-punch set made of steel. After that, two-step pressureless sintering was carried out at sintering temperature and time 600°C and 3 hours respectively. It was observed that the sintered cylindrical specimens of 30 mm diameter were prepared successfully. The graded composite specimens were analysed and the properties such as density, microstructure and hardness were measured. It was found that after sintering process, the diameter of the graded cylindrical structure was decreased. Using both Archimedes method and rule of mixture (ROM), he density of structure was measured. The obtained results revealed that the microvickers hardness was increased as the ceramic component increases in the graded layer. Moreover, it was observed that the interface of the graded structure is clearly distinguished within the multilayer stack and the ceramic particles are almost uniformly distributed in the Al matrix.

Development of an on-line electrochemical analyser for trace level aluminium

International Nuclear Information System (INIS)

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

2003-01-01

An in-house designed computerised flow injection (FI) system for low-level aluminium analysis is examined. A simple, low cost electrochemical detection system has been implemented with computerised control and data acquisition system. The system consists of a commercial electrochemical analyser, FI components (manifold, pumps and valves) and an in-house designed control system to perform automated analysis. This system was developed to study aluminium speciation in water, particularly for drinking water. The analytical technique was based upon the complexation reaction between aluminium and a ligand--DASA (1,2-dihydroxy-anthraquinone-3-sulphonic acid). 'Labile' and total aluminium concentrations, Al labile and Al total , respectively, were determined by measuring the sample before and after UV irradiation by amperometry at +0.6 V. The limit of detection for this technique was 10 μg/l (0.37 μM) and the linear calibration range was up to 1.6 mg/l (60 μM) with r 2 value of 0.999. The Al labile /Al total ratios of the water treated by 40, 80 and 100 mg/l of alum using a laboratory scale pilot plant to simulate conventional drinking water treatment processes were found to be 0.4, 0.5 and 0.8, respectively. These results indicated that when higher alum dose was employed, the residual aluminium was present mostly as the 'labile' species. Whereas, if the treatment process was not running at its optimum condition (underdosing), a large portion of aluminium was present as natural organic matter (NOM) - aluminium complexes in the treated water. The system offers a practical and effective means of providing extended knowledge of residual aluminium in drinking water

Aluminium Matrix Composites Reinforced with Co-continuous Interlaced Phases Aluminium-alumina Needles

Directory of Open Access Journals (Sweden)

Elvio de Napole Gregolin

2002-09-01

Full Text Available An Al-5SiO2 (5 wt% of SiO2 aluminium matrix fiber composite was produced where the reinforcement consists of fossil silica fibers needles. After being heat-treated at 600 °C, the original fiber morphology was retained but its microstructure changed from solid silica to an interconnected (Al-Si/Al2O3 interlaced structure named co-continuous composite. A technique of powder metallurgy, using commercial aluminium powder and the silica fibers as starting materials, followed by hot extrusion, was used to produce the composite. The co-continuous microstructure was obtained partially or totally on the fibers as a result of the reaction, which occurs during the heat treatment, first by solid diffusion and finally by the liquid Al-Si in local equilibrium, formed with the silicon released by reaction. The internal structure of the fibers was characterized using field emission electron microscope (FEG-SEM and optical microscopy on polished and fractured samples.

Aluminium alloys in municipal solid waste incineration bottom ash.

Science.gov (United States)

Hu, Yanjun; Rem, Peter

2009-05-01

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

Trace aluminium determination and sampling problems of archeological bone employing destructive neutron activation analysis

International Nuclear Information System (INIS)

Blotcky, A.J.; Rack, E.P.; Recker, R.R.; Leffler, J.A.; Teitelbaum, S.

1978-01-01

A destructive neutron activation analysis procedure was developed for determining trace aluminium content in bone. The method is based on a carefully planned sample preparation, irradiation at a neutron flux for 3.1x10 11 nxcm -2 xs -1 for 5 minutes, and chemical separation based on ion exchange. It was found that bone samples soaked in aluminium containing soil gave highly elevated aluminium values as a result of the aluminium adsorption into the bone matrix. The maximum aluminium content values for prehistoric bones are larger than those of modern bones and comparable to aluminium levels present in bone from renal patients. (T.G.)

Fire exposed aluminium structures

NARCIS (Netherlands)

Maljaars, J.; Fellinger, J.E.J.; Soetens, F.

2005-01-01

Material properties and mechanical response models for fire design of steel structures are based on extensive research and experience. Contrarily, the behaviour of aluminium load bearing structures exposed to fire is relatively unexplored. This article gives an overview of physical and mechanical

Guide lines for control and supervision of dump leaching. Application to the inframarginal uranium ore of the Cellier mine

International Nuclear Information System (INIS)

Pineau, J.L.; Yvon, J.; Blazy, P.

1984-01-01

The Cellier mine processes inframarginal uranium ores by a slow dump leaching. Fragmentary information concerning the evolution of the chemical properties of the solutions (inflow-outflow) as a function of the time has been the object of an analysis of data. The latter, which was both descriptive and predictive, made it possible on the one hand to identify facts which have intervened at the time of leaching and on the other hand to pinpoint the influence of the time factor and of the associations of chemical elements (aluminium, phosphorus, etc.) on the passing into solution of the uranium. As this treatment gives only a global view of the problem, it was completed by a mineralogical analysis. The fine mineralogical analysis of the fractions, made soluble by sulphuric attack in a heap, shows that sulphated concretions isolate the uranium from the leaching liquor. A screen of sulphate is composed of a macroscopic web of gypsum (calcium sulphate) in which a microscopic web of hydrated magnesium sulphate is inserted. In the gypsum web are trapped phosphorus minerals and in the magnesium sulphate web manganese and aluminium minerals. As regards the uranium, it is either distributed in the form of fine inclusions of uranyl hydroxide, or associated to chlorinated forms, derived from the treatment aids [fr

Manufacturing and Machining Challenges of Hybrid Aluminium Metal Matix Composites

Science.gov (United States)

Baburaja, Kammuluri; Sainadh Teja, S.; Karthik Sri, D.; Kuldeep, J.; Gowtham, V.

2017-08-01

Manufacturing which involves material removal processes or material addition processes or material transformation processes. One or all the processes to obtain the final desired properties for a material with desired shape which meets the required precision and accuracy values for the expected service life of a material in working conditions. Researchers found the utility of aluminium to be the second largest after steel. Aluminium and its metal matrix composite possess wide applications in various applications in aerospace industry, automobile industry, Constructions and even in kitchen utensils. Hybrid Al-MMCconsist of two different materials, and one will be from organic origin along with the base material. In this paper an attempt is made to bring out the importance of utilization of aluminium and the challenges concerned in manufacturing and machining of hybrid aluminium MMC.

Chemical mimicking of bio-assisted aluminium extraction by Aspergillus niger's exometabolites.

Science.gov (United States)

Boriová, Katarína; Urík, Martin; Bujdoš, Marek; Pifková, Ivana; Matúš, Peter

2016-11-01

Presence of microorganisms in soils strongly affects mobility of metals. This fact is often excluded when mobile metal fraction in soil is studied using extraction procedures. Thus, the first objective of this paper was to evaluate strain Aspergillus niger's exometabolites contribution on aluminium mobilization. Fungal exudates collected in various time intervals during cultivation were analyzed and used for two-step bio-assisted extraction of alumina and gibbsite. Oxalic, citric and gluconic acids were identified in collected culture media with concentrations up to 68.4, 2.0 and 16.5 mmol L -1 , respectively. These exometabolites proved to be the most efficient agents in mobile aluminium fraction extraction with aluminium extraction efficiency reaching almost 2.2%. However, fungal cultivation is time demanding process. Therefore, the second objective was to simplify acquisition of equally efficient extracting agent by chemically mimicking composition of main organic acid components of fungal exudates. This was successfully achieved with organic acids mixture prepared according to medium composition collected on the 12th day of Aspergillus niger cultivation. This mixture extracted similar amounts of aluminium from alumina compared to culture medium. The aluminium extraction efficiency from gibbsite by organic acids mixture was lesser than 0.09% which is most likely because of more rigid mineral structure of gibbsite compared to alumina. The prepared organic acid mixture was then successfully applied for aluminium extraction from soil samples and compared to standard single step extraction techniques. This showed there is at least 2.9 times higher content of mobile aluminium fraction in soils than it was previously considered, if contribution of microbial metabolites is considered in extraction procedures. Thus, our contribution highlights the significance of fungal metabolites in aluminium extraction from environmental samples, but it also simplifies the

Electrical connection for aluminium conductors in automotive applications : Prestudy of available solutions for electrical connection methods of aluminium cables

OpenAIRE

Hamedi, Emilia

2017-01-01

Due to increasing weight of electrical component and wiring harnesses in a vehicle contrary to the demand of light constructed vehicles as well as the constantly increasing and fluctuating price of copper compared to aluminium’s stable and far lower price, the use of aluminium conductors as an alternative have been promoted.  This thesis work lay theoretical research of the available methods used for electrical connection of aluminium conductors in order to increase the knowledge about the av...

Molecular structure of dextran sulphate sodium in aqueous environment

Science.gov (United States)

Yu, Miao; Every, Hayley A.; Jiskoot, Wim; Witkamp, Geert-Jan; Buijs, Wim

2018-03-01

Here we propose a 3D-molecular structural model for dextran sulphate sodium (DSS) in a neutral aqueous environment based on the results of a molecular modelling study. The DSS structure is dominated by the stereochemistry of the 1,6-linked α-glucose units and the presence of two sulphate groups on each α-glucose unit. The structure of DSS can be best described as a helix with various patterns of di-sulphate substitution on the glucose rings. The presence of a side chain does not alter the 3D-structure of the linear main chain much, but affects the overall spatial dimension of the polymer. The simulated polymers have a diameter similar to or in some cases even larger than model α-hemolysin nano-pores for macromolecule transport in many biological processes, indicating a size-limited translocation through such pores. All results of the molecular modelling study are in line with previously reported experimental data. This study establishes the three-dimensional structure of DSS and summarizes the spatial dimension of the polymer, serving as the basis for a better understanding on the molecular level of DSS-involved electrostatic interaction processes with biological components like proteins and cell pores.

Magnesium sulphate as an anticonvulsant in the management of eclampsia

International Nuclear Information System (INIS)

Ahmed, R.

2004-01-01

Objective: To evaluate the use of magnesium sulphate (MgSO/sub 4/) as an anticonvulsant in the management of eclamptic patients. Patients and Methods: Out of a total of 6050 pregnant women, 31 patients had eclampsia and were managed according to the set protocol. MgSO/sub 4/ 'Nas given to eclamptic patients according to protocol who had no contraindication to this agent. Recurrence of convulsion, side effects of magnesium sulphate, maternal and fetal outcome was noted. Results: Over two years' study period, out of 6050 patients, 31 were admitted with eclampsia (0.51 %). There was no maternal death. Out of 31 eclamptic patients only 5 patients were booked. Twenty-two patients (70.9%) were primigravida and 9 (29%) were multigravida. Seventeen (54%) were less than 20 years of age, 22 (79.9%) patients were admitted with antepartum and 6 (19.35%) had postpartum eclampsia. Magnesium sulphate was effective in 29 (93.54%) patients. Fifteen patients delivered by caesarean (C) section and 16 delivered vaginally. Twenty-nine (93.5%) babies were born alive. Two patients had recurrent convulsion i.e. 6.4%. Only one patient had respiratory depression after the use of magnesium sulphate. Conclusion: Eclampsia was well controlled by the use of MgSO/sub 4/. There were only 2 patients who had recurrence of convulsion. Convulsions were controlled in 29 (93.54%) patients despite lack of monitoring facilities of serum magnesium level. (author)

Measurement of oxide-layer thickness of internal granules in high-purity aluminium

International Nuclear Information System (INIS)

Takacs, S.; Ditroi, F.; Mahunka, I.

1989-01-01

Charged-particle activation analysis was used for the determination of bulk oxygen concentration in aluminium. High-purity aluminium samples and mixtures containing different amounts of alumina were irradiated by 13 MeV 3 He particles. The aim of the investigation was to determine the oxide-layer thickness on the surface of internal aluminium granules. The measurement was carried out by determining the bulk oxygen concentration in the samples, and calculating the oxide-layer thickness, by using model conditions about the microstructure of the aluminium samples. (author) 5 refs

Correlation analysis between sulphate content and leaching of sulphates in recycled aggregates from construction and demolition wastes.

Science.gov (United States)

Barbudo, Auxi; Galvín, Adela P; Agrela, Francisco; Ayuso, Jesús; Jiménez, Jose Ramón

2012-06-01

In some recycled aggregates applications, such as component of new concrete or roads, the total content of soluble sulphates should be measured and controlled. Restrictions are usually motivated by the resistance or stability of the new structure, and in most cases, structural concerns can be remedied by the use of techniques such as sulphur-resistant cements. However, environmental risk assessment from recycling and reuse construction products is often forgotten. The purpose of this study is to analyse the content of soluble sulphate on eleven recycled aggregates and six samples prepared in laboratory by the addition of different gypsum percentages. As points of reference, two natural aggregates were tested. An analysis of the content of the leachable amount of heavy metals regulated by European regulation was included. As a result, the correlation between solubility and leachability data allow suggest a limiting gypsum amount of 4.4% on recycled aggregates. This limit satisfies EU Landfill Directive criteria, which is currently used as reference by public Spanish Government for recycled aggregates in construction works. Copyright © 2012 Elsevier Ltd. All rights reserved.

Sulphated glycosaminoglycans and proteoglycans in the developing vertebral column of juvenile Atlantic salmon (Salmo salar).

Science.gov (United States)

Hannesson, Kirsten O; Ytteborg, Elisabeth; Takle, Harald; Enersen, Grethe; Bæverfjord, Grete; Pedersen, Mona E

2015-08-01

In the present study, the distribution of sulphated glycosaminoglycans (GAGs) in the developing vertebral column of Atlantic salmon (Salmo salar) at 700, 900, 1100 and 1400 d° was examined by light microscopy. The mineralization pattern was outlined by Alizarin red S and soft structures by Alcian blue. The temporal and spatial distribution patterns of different types of GAGs: chondroitin-4-sulphate/dermatan sulphate, chondroitin-6-sulphate, chondroitin-0-sulphate and keratan sulphate were addressed by immunohistochemistry using monoclonal antibodies against the different GAGs. The specific pattern obtained with the different antibodies suggests a unique role of the different GAG types in pattern formation and mineralization. In addition, the distribution of the different GAG types in normal and malformed vertebral columns from 15 g salmon was compared. A changed expression pattern of GAGs was found in the malformed vertebrae, indicating the involvement of these molecules during the pathogenesis. The molecular size of proteoglycans (PGs) in the vertebrae carrying GAGs was analysed with western blotting, and mRNA transcription of the PGs aggrecan, decorin, biglycan, fibromodulin and lumican by real-time qPCR. Our study reveals the importance of GAGs in development of vertebral column also in Atlantic salmon and indicates that a more comprehensive approach is necessary to completely understand the processes involved.

The varied functions of aluminium-activated malate transporters-much more than aluminium resistance.

Science.gov (United States)

Palmer, Antony J; Baker, Alison; Muench, Stephen P

2016-06-15

The ALMT (aluminium-activated malate transporter) family comprises a functionally diverse but structurally similar group of ion channels. They are found ubiquitously in plant species, expressed throughout different tissues, and located in either the plasma membrane or tonoplast. The first family member identified was TaALMT1, discovered in wheat root tips, which was found to be involved in aluminium resistance by means of malate exudation into the soil. However, since this discovery other family members have been shown to have many other functions such as roles in stomatal opening, general anionic homoeostasis, and in economically valuable traits such as fruit flavour. Recent evidence has also shown that ALMT proteins can act as key molecular actors in GABA (γ-aminobutyric acid) signalling, the first evidence that GABA can act as a signal transducer in plants. © 2016 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

Sulphation of calcium-based sorbents in circulating fluidised beds under oxy-fuel combustion conditions

Energy Technology Data Exchange (ETDEWEB)

Francisco Garcia-Labiano; Luis F. de Diego; Alberto Abad; Pilar Gayan; Margarita de las Obras-Loscertales; Aranzazu Rufas; Juan Adanez [Instituto de Carboquimica (CSIC), Zaragoza (Spain). Dept. Energy and Environment

2009-07-01

Sulphur Retention (SR) by calcium-based sorbents is a process highly dependent on the temperature and CO{sub 2} concentration. In circulating fluidised beds combustors (CFBC's) operating under oxy-fuel conditions, the sulphation process takes place in atmospheres enriched in CO{sub 2} with bed concentrations that can vary from 40 to 95%. Under so high CO{sub 2} concentrations, very different from that in conventional coal combustion atmosphere with air, the calcination and sulphation behaviour of the sorbent must be defined to optimise the SR process in the combustor. The objective of this work was to determine the SO{sub 2} retention capacity of a Spanish limestone at typical oxy-fuel conditions in CFBC's. Long term duration tests of sulphation (up to 24 h), to simulate the residence time of sorbents in CFBC's, were carried out by thermogravimetric analysis (TGA). Clear behaviour differences were found under calcining and non-calcining conditions. Especially relevant was the result obtained at calcining conditions but close to the thermodynamic temperature given for sorbent calcination. This situation must be avoided in CFBC's because the CO{sub 2} produced inside the particle during calcination can destroy the particles if a non-porous sulphate product layer has been formed around the particle. The effect of the main variables on the sorbent sulphation such as SO{sub 2} concentration, temperature, and particle size were analysed in the long term TGA tests. These data were also used to determine the kinetic parameters for the sulphation under oxy-fuel combustion conditions, which were able to adequately predict the sulphation conversion values in a wide range of operating conditions. 20 refs., 5 figs., 2 tabs.

Spore-forming, Desulfosporosinus-like sulphate-reducing bacteria from a shallow aquifer contaminated with gasoline.

Science.gov (United States)

Robertson, W J; Franzmann, P D; Mee, B J

2000-02-01

Previous studies on the geochemistry of a shallow unconfined aquifer contaminated with hydrocarbons suggested that the degradation of some hydrocarbons was linked to bacterial sulphate reduction. There was attenuation of naphthalene, 1,3,5-trimethylbenzene (TMB), toluene, p-xylene and ethylbenzene in the groundwater with concomitant loss of sulphate. Here, the recovery of eight strains of sulphate-reducing bacteria (SRB) from the contaminated site is reported. All were straight or curved rod-shaped cells which formed endospores. Amplification and sequencing of the 16S rDNA indicated that the strains were all sulphate reducers of the Gram-positive line of descent, and were most closely related to Desulfosporosinus (previously Desulfotomaculum) orientis DSM 8344 (97-98.9% sequence similarity). The strains clustered in three phylogenetic groups based on 16S rRNA sequences. Whole cell fatty acid compositions were similar to those of D. orientis DSM 8344, and were consistent with previous studies of fatty acids in soil and groundwater from the site. Microcosms containing groundwater from this aquifer indicated a role for sulphate reduction in the degradation of [ring-UL-14C]toluene, but not for the degradation of [UL-14C]benzene which could also be degraded by the microcosms. Adding one of the strains that was isolated from the groundwater (strain T2) to sulphate-enriched microcosms increased the rate of toluene degradation four- to 10-fold but had no effect on the rate of benzene degradation. The addition of molybdate, an inhibitor of sulphate reduction, to the groundwater samples decreased the rate of toluene mineralization. There was no evidence to support the mineralization of [UL-14C]benzene, [ring-UL-14C]toluene or unlabelled m-xylene, p-xylene, ethylbenzene, TMB or naphthalene by any of the strains in pure culture. Growth of all the strains was completely inhibited by 100 micromol l-1 TMB.

Corrosion of research reactor aluminium clad spent fuel in water

International Nuclear Information System (INIS)

2003-01-01

This report describes research performed in ten laboratories within the framework of the IAEA Co-ordinated Research Project on Corrosion of Research Reactor Aluminium Clad Spent Fuel in Water. The project consisted of exposure of standard racks of corrosion coupons in the spent fuel pools of the participating research reactor laboratories and the evaluation of the coupons after predetermined exposure times, along with periodic monitoring of the storage water. A group of experts in the field contributed a state of the art review and provided technical supervision of the project. Localized corrosion mechanisms are notoriously difficult to understand, and it was clear from the outset that obtaining consistency in the results and their interpretation from laboratory to laboratory would depend on the development of an excellent set of experimental protocols. These experimental protocols are described in the report together with guidelines for the maintenance of optimum water chemistry to minimize the corrosion of aluminium clad research reactor fuel in wet storage. A large database on corrosion of aluminium clad materials has been generated from the CRP and the SRS corrosion surveillance programme. An evaluation of these data indicates that the most important factors contributing to the corrosion of the aluminium are: (1) High water conductivity (100-200 μS/cm); (2) Aggressive impurity ion concentrations (Cl - ); (3) Deposition of cathodic particles on aluminium (Fe, etc.); (4) Sludge (containing Fe, Cl - and other ions in concentrations greater than ten times the concentrations in the water); (5) Galvanic couples between dissimilar metals (stainless steel-aluminium, aluminium-uranium, etc); (6) Scratches and imperfections (in protective oxide coating on cladding); (7) Poor water circulation. These factors operating both independently and synergistically may cause corrosion of the aluminium. The single most important key to preventing corrosion is maintaining good

Electrotransport of hydrogen in aluminium at 20 and 800 deg C

International Nuclear Information System (INIS)

Byalik, O.M.; Volkotrub, N.P.; Pinchuk, V.M.; Golub, L.V.; Degtyarenko, G.E.; Ivanchuk, D.F.

1982-01-01

Electrotransport of hydrogen in the field of crystal lattice of aluminium is investigated at the special installation using the method of measurement of electric resistivity. Quantum-mechanical calculation of H + and H - ions interaction with aluminium atoms is made to clarify the mechanizm of electrotransport. It is shown, that probability of the H + and H - ions permeation in the field of aluminium crystal lattice can be judged by the ratio of δE 1 (the lattice potential barrier) and δ 2 (the local energy minium in the case of atom arrangement in the lattice plane). The value of potentials of hydrogen ions interaction with aluminium lattice is obtained in the result os solution of the Schroedinger equation

AE Monitoring of Diamond Turned Rapidly Soldified Aluminium 443

International Nuclear Information System (INIS)

Onwuka, G; Abou-El-Hossein, K; Mkoko, Z

2017-01-01

The fast replacement of conventional aluminium with rapidly solidified aluminium alloys has become a noticeable trend in the current manufacturing industries involved in the production of optics and optical molding inserts. This is as a result of the improved performance and durability of rapidly solidified aluminium alloys when compared to conventional aluminium. Melt spinning process is vital for manufacturing rapidly solidified aluminium alloys like RSA 905, RSA 6061 and RSA 443 which are common in the industries today. RSA 443 is a newly developed alloy with few research findings and huge research potential. There is no available literature focused on monitoring the machining of RSA 443 alloys. In this research, Acoustic Emission sensing technique was applied to monitor the single point diamond turning of RSA 443 on an ultrahigh precision lathe machine. The machining process was carried out after careful selection of feed, speed and depths of cut. The monitoring process was achieved with a high sampling data acquisition system using different tools while concurrent measurement of the surface roughness and tool wear were initiated after covering a total feed distance of 13km. An increasing trend of raw AE spikes and peak to peak signal were observed with an increase in the surface roughness and tool wear values. Hence, acoustic emission sensing technique proves to be an effective monitoring method for the machining of RSA 443 alloy. (paper)

Determination of Oversulphated Chondroitin Sulphate and Dermatan Sulphate in unfractionated heparin by (1)H-NMR - Collaborative study for quantification and analytical determination of LoD.

Science.gov (United States)

McEwen, I; Mulloy, B; Hellwig, E; Kozerski, L; Beyer, T; Holzgrabe, U; Wanko, R; Spieser, J-M; Rodomonte, A

2008-12-01

Oversulphated Chondroitin Sulphate (OSCS) and Dermatan Sulphate (DS) in unfractionated heparins can be identified by nuclear magnetic resonance spectrometry (NMR). The limit of detection (LoD) of OSCS is 0.1% relative to the heparin content. This LoD is obtained at a signal-to-noise ratio (S/N) of 2000:1 of the heparin methyl signal. Quantification is best obtained by comparing peak heights of the OSCS and heparin methyl signals. Reproducibility of less than 10% relative standard deviation (RSD) has been obtained. The accuracy of quantification was good.

Sol gel synthesis for preparation of yttrium aluminium garnet

NARCIS (Netherlands)

Vrolijk, J.W.G.A.; Willems, J.W.M.M.; Metselaar, R.; With, de G.; Terpstra, R.A.; Metselaar, R.

1989-01-01

Sol-gel—synthesis for preparation of pure yttrium aluminium garnet powder with small grain size is subject of this ongoing study. Starting materials were sulfates and chlorides of yttrium and aluminium. To obtain pure YAG (Y3A1SO1Z) pH during hydrolysis as well as temperature during calcination and

Studies on calcium, magnesium and sulphate in the Mandovi and Zuari river system (Goa)

Digital Repository Service at National Institute of Oceanography (India)

SenGupta, R.; Naik, S.

-conservative parameters. Sulphate, however behaves in a purely conservative manner and remains in a steady state in the rivers. A'Simple mixture'relationship is applied to calculate the dilution and mixing processes in the rivers using calcium, magnesium and sulphate...

Biotreatment of Cr(VI) contaminated waters by sulphate reducing bacteria fed with ethanol

International Nuclear Information System (INIS)

Pagnanelli, F.; Cruz Viggi, C.; Cibati, A.; Uccelletti, D.; Toro, L.; Palleschi, C.

2012-01-01

Highlights: ► Use of ethanol as electron donor for sulphate-reducing bacteria for the treatment of Cr(VI). ► Isolation of contribution in Cr removal (adsorption vs. bioprecipitation). ► Bioassessment of the process effectiveness by ecotoxicological in vivo tests using C. elegans. - Abstract: Biological treatment of Cr(VI) contaminated waters was performed in fixed bed reactors inoculated with SRB (sulphate-reducing bacteria) growing on ethanol. Treatment efficiency was evaluated by checking chemical abatement of Cr(VI) and by ecotoxicological tests using the nematode Caenorhabditis elegans. A preliminary comparison between ethanol and lactate was performed, denoting that using ethanol, the same values of final sulphate abatement were obtained. In addition ethanol showed to be a substrate more competitive than lactate in kinetic terms. Fixed bed column reactors were continuously fed with a solution containing sulphates (3 g L −1 ), ethanol (1.5 g L −1 ) and Cr(VI) (50 mg L −1 ). At steady state the column inoculated with SRB removed 65 ± 5% of sulphate and 95 ± 5% of chromium. Bioactive removal mechanisms predominated over biosorption. Diminution of Cr(VI) toxicity was assessed by using the nematode C. elegans as a test organism showing that the survival of nematodes was 20% in the presence of the untreated influent and raised up to 53% when the nematodes were exposed to the treated effluent.

Defect generation during solidification of aluminium foams

International Nuclear Information System (INIS)

Mukherjee, M.; Garcia-Moreno, F.; Banhart, J.

2010-01-01

The reason for the frequent occurrence of cell wall defects in metal foams was investigated. Aluminium foams often expand during solidification, a process which is referred as solidification expansion (SE). The effect of SE on the structure of aluminium foams was studied in situ by X-ray radioscopy and ex situ by X-ray tomography. A direct correlation between the magnitude of SE and the number of cell wall ruptures during SE and finally the number of defects in the solidified foams was found.

Aluminium, extractable from soil samples by the acid ammonium acetate soil-testing method

Directory of Open Access Journals (Sweden)

Osmo Mäkitie

1968-05-01

Full Text Available The extractant, 0.5 M acetic acid –0.5 M ammonium acetate at pH 4.65, which is used in soil-testing, extracts relatively high amounts of aluminium from acid soils. The mean values of acetate-extractable aluminium at pH 4.65, 1.75 meq Al/100 g of soil, and of exchangeable aluminium (M KCI extraction, 0.41 meq Al were obtained from a material of 30 samples of acid soils (Table 2. Several other acetic acid ammonium acetate extractants, from M acetic acid to M ammonium acetate solution were also used for studying the extractability of soil aluminium. The soil-testing extractant can be used for the estimation of the soluble amounts of aluminium in acid soils, however, further studies are needed for a better interpretation of the ammonium acetate extractable (at pH 4.65 aluminium in our soils.

Formulation and evaluation and terbutaline sulphate and ...

African Journals Online (AJOL)

We report the use of low rugosity lactose, product of controlled crystallization of this carrier, in the formulation of terbutaline sulphate and beclomethasone dipropionate dry powder inhalers. The deposition patterns obtained with inhalation mixtures consisting of the modified lactose and each of the micronised drugs ...

Factors affecting the aluminium content of human femoral head and neck.

Science.gov (United States)

Zioła-Frankowska, Anetta; Dąbrowski, Mikołaj; Kubaszewski, Łukasz; Rogala, Piotr; Frankowski, Marcin

2015-11-01

Tissues for the study were obtained intraoperatively during hip replacement procedures from 96 patients. In all the cases, the indication for this treatment was primary or secondary degenerative changes in the hip joint. The subject of the study was the head and neck of the femur, resected in situ. Aluminium concentrations measured in femoral head and neck samples from patients aged between 25 and 91 were varied. Statistical methods were applied to determine the variations in relation to the parameters from the background survey. Significant differences in the aluminium content of femoral head samples were observed between patients under and over 60 years of age. Based on the results, it was confirmed that the aluminium accumulates in bones over a lifetime. The study showed that the content of aluminium in the head and neck of the femur depends on the factors such as: type of medicines taken, contact with chemicals at work, differences in body anatomy and sex. The study on the levels of aluminium in bones and the factors affecting its concentration is a valuable source of information for further research on the role of aluminium in bone diseases. Based on the investigations, it was found that the GF-AAS technique is the best analytical tool for routine analysis of aluminium in complex matrix samples. The use of femoral heads in the investigations was approved by the Bioethics Committee of the University of Medical Sciences in Poznań (Poland). Copyright © 2015 Elsevier Inc. All rights reserved.

Crystal structure and phase composition of aluminium thin films with holmium additions

International Nuclear Information System (INIS)

Koleshko, V.M.; Belitskij, V.F.; Obukhov, V.E.; Rumak, N.V.; Urban, T.P.

1984-01-01

The effect of holmium additions on the crystal structure and phase composition of thin aluminium films has been studied. A regularity in grain size changes in aluminium thin films versus the holmium content in them is established. The holmium introduction is shown to result in the appearance of axial texture in the aluminium films, the texture axis being determined by the quantity of the addition. During heat treatment of the aluminium films, containing holmium additions, in the range of low ( approximately 100-200 deg C) annealing temperatures holmium monohydroxide is formed, and at annealing temperatures 300 deg C 0 3 is formed

The effects of aluminium and selenium supplementation on brain ...

African Journals Online (AJOL)

This in vivo study was designed to investigate the potential of aluminium (Al), in the absence of added iron, to participate in either antioxidant or pro-oxidant events. Some markers of oxidative stress were determined in liver and brain of rats exposed to aluminium lactate, either alone or in the presence of dietary supplements ...

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

International Nuclear Information System (INIS)

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

2008-01-01

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 to calculate the initial formal hydrolysis ratio of hydrolysed aluminium-ion solutions. Several solutions of pure hydrolytic species including aluminium monomers (AlCl 3 ), Al 13 polynuclear cluster ([Al 13 O 4 (OH) 24 (H 2 O) 12 ] 7+ ), Al 30 polynuclear cluster ([Al 30 O 8 (OH) 56 (H 2 O) 26 ] 18+ ) and a suspension of nanoparticulate aluminium hydroxide have been used as 'reference standards' to validate the proposed potentiometric method. Other important variables in the potentiometric determination of the hydrolysis ratio have also been optimised including the concentration of aluminium and the type and strength of alkali (Trizma-base, NH 3 , NaHCO 3 , Na 2 CO 3 and KOH). The results of the potentiometric analysis have been cross-verified by quantitative 27 Al solution nuclear magnetic resonance ( 27 Al NMR) measurements. The 'formal' hydrolysis ratio of a commercial basic aluminium chloride has been measured as an example of a practical application of the developed technique

Aluminium concentration versus the base cation to aluminium ratio as predictors for aluminium toxicity in Pinus sylvestris and Picea abies seedlings

NARCIS (Netherlands)

Schöll, van L.; Keltjens, W.G.; Hoffland, E.; Breemen, van N.

2004-01-01

Aluminium (Al) toxicity is considered an important factor in forest deterioration caused by soil acidification. A ratio of base cations (BC) to Al in the soil solution lower than 1 is widely used as an indicator for potentially adverse effects on tree health. In our view, the validity of the

Magnesium sulphate for women at risk of preterm birth for neuroprotection of the fetus

NARCIS (Netherlands)

Doyle, Lex W.; Crowther, Caroline A.; Middleton, Philippa; Marret, Stephane; Rouse, Dwight

2009-01-01

Background Epidemiological and basic science evidence suggests that magnesium sulphate before birth may be neuroprotective for the fetus. Objectives To assess the effects of magnesium sulphate as a neuroprotective agent when given to women considered at risk of preterm birth. Search strategy We

Effect of microcrystallization on pitting corrosion of pure aluminium

International Nuclear Information System (INIS)

Meng Guozhe; Wei Liyan; Zhang Tao; Shao Yawei; Wang Fuhui; Dong Chaofang; Li Xiaogang

2009-01-01

A microcrystalline aluminium film with grain size of about 400 nm was prepared by magnetron sputtering technique. Its corrosion behaviour was investigated in NaCl containing acidic solution by means of potentiodynamic polarization curves and electrochemical noise (EN). The polarization results indicated that the corrosion potential of the sample shifted towards more positive direction, while its corrosion current density decreased compared with that of pure coarse-grain Al. The EN analysis based on stochastic model demonstrated that there existed two kinds of effect of microcrystallization on the pitting behaviour of pure aluminium: (1) the rate of pit initiation is accelerated, (2) the pit growth process was impeded. This leads to the enhancement of pitting resistance for the microcrystallized aluminium.

Three body abrasion of laser surface alloyed aluminium AA1200

CSIR Research Space (South Africa)

Mabhali, Luyolo AB

2012-06-01

Full Text Available Laser surface alloying of aluminium AA1200 was performed with a 4 kW Nd:YAG laser to improve the abrasion wear resistance. Aluminium surfaces reinforced with metal matrix composites and intermetallic phases were achieved. The phases present depended...

Neutron activation analysis of baths forming conversion layer on aluminium

International Nuclear Information System (INIS)

Szilagyi, Istvan; Maleczki, Emil; Bodizs, Denes

1988-01-01

Chromate layers were formed on the surface of aluminium using yellow and green chromating solutions. For the determination of the aluminium content neutron activation method was used. Nuclear effects disturbing the determination were eliminated by double irradiation technique. (author) 8 refs.; 4 figs

Dietary exposure to aluminium and health risk assessment in the residents of Shenzhen, China.

Science.gov (United States)

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

2014-01-01

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.

Decomposition of oxidezed lead and aluminium thin films on molybdenum substrates

International Nuclear Information System (INIS)

Makarovskij, N.A.

1981-01-01

The decomposition of oxidized solid phase lead and aluminium thin films on molybdenum substrates in the process of diffusion annealing in the 5x10 -5 mm Hg vacuum at temperatures from 280 to 320 deg C and from 500 to 560 deg C, respectively, is investigated. The conclusion is made that failure of oxidized lead and aluminium thin film coatings is carried out by the mechanism of volumetric self-diffusion. Experimentally established values of activation energies of the process of lead (Qsub(Mo)sup(Pb)=29 kcal/mol) and aluminium (Qsub(Mo)sup(Al)=35 kcal/mol) film failure are close to corresponding activation energies of lead and aluminium volumetric self-diffusion, which agrees with the conclusions made [ru

Corrosion Inhibition of Aluminium in Acid Media By Citrullus Colocynthis Extract

Directory of Open Access Journals (Sweden)

Rajkiran Chauhan

2011-01-01

Full Text Available Inhibition of corrosion of aluminium in acid solution by methanol extract of Citrullus colocynthis plant has been studied using mass loss and thermometric measurements. It has been found that the plant extract act as a good corrosion inhibitor for aluminium in all concentrations of sulphuric and hydrochloric acid solution. The inhibition action depends on the concentration of acid and inhibitor. Results for mass loss and thermometric measurement indicate that inhibition efficiency increase with increasing inhibitor concentration. The inhibition action of the plant extract is discussed in view of Langmuir adsorption isotherm. It has been observed that the adsorption of the extract on aluminium surface is a spontaneous process. The plant extract provides a good protection to aluminium against corrosion.

Method of preparing an Al-Ti-B grain refiner for aluminium-comprising products, and a method of casting aluminium products

OpenAIRE

Brinkman, H.J.; Duszczyk, J.; Katgerman, L.

1999-01-01

The invention relates to a method of preparing an Al-Ti-B grain refiner for cast aluminium-comprising products. According to the invention the preparation is realized by mixing powders selected from the group comprising aluminium, titanium, boron, and alloys and intermetallic compounds thereof, compressing, heating in an inert environment until an exothermic reaction is initiated and cooling. It has been shown that when the grain refiner thus prepared is applied, the quality of cast products ...

An aluminium evaporation source for ion plating

International Nuclear Information System (INIS)

Walley, P.A.; Cross, K.B.

1977-01-01

Ion plating with aluminium is becoming increasingly accepted as a method of anti-corrosion surface passivation, the usual requirements being for a layer between 12 and 50 microns in thickness, (0.0005 to 0.002). The evaporation system described here offers a number of advantages over high power electron beam sources when used for aluminium ion plating. The source consists of a resistively heated, specially shaped, boron nitride-titanium diboride boat and a metering feed system. Its main features are small physical size, soft vacuum compatibility, low power consumption and metered evaporation output. (author)

Bioactive type glass-ceramics within incorporated aluminium

International Nuclear Information System (INIS)

Volzone, C.; Stabile, F.M.; Ortiga, J.

2012-01-01

Bioactive glass-ceramics are used as biomaterials for the reparation of bone tissue. They are prepared, generally, by bioglass of specific composition for each particular use. The aluminium addition in the formulation at very small quantities influences on the structural properties. Two glass-ceramics obtained by P 2 O 5 -Na 2 O-CaO-SiO 2 formulation within aluminium (0.5 % in Al 2 O 3 base) added through a reactive alumina and purified feldspar were analyzed. The results showed structural differences between both glass-ceramics. (author)

Automatic colorimetric determination of low concentrations of sulphate for measuring sulphur dioxide in ambient air

Energy Technology Data Exchange (ETDEWEB)

Persson, G A

1966-01-01

An automatic colorimetric method for the determination of low concentrations of sulphate (0-10 microgram/ml) using the thoron indicator is described. Total amounts of sulphate as small as 0.3 micrograms can be determined. The sulphate is precipitated with barium perchlorate and the excess of barium is indicated with 1-(o-arsenophenylazo)-2-naphthol-3-6-disulfonic acid(thoron). The procedure is worked out primarily for the determination of sulphur dioxide in air after absorption in diluted hydrogen peroxide.

Modelling the competition between sulphate reducers and methanogens in a thermophilic methanol-fed bioreactor

NARCIS (Netherlands)

Spanjers, H.; Weijma, J.; Abusam, A.

2002-01-01

Sulphate can be removed from wastewater by means of biological anaerobic reduction to sulphide. The reduction requires the presence of a substrate that can serve as an electron donor. Methanol a suitable electron donor for sulphate reduction under thermophilic conditions. In an anaerobic system

Aluminium-rich corner in Al-Cu-La system

International Nuclear Information System (INIS)

Yunusov, I.; Ganiev, I.N.

1990-01-01

Aluminium corner of Al-Cu-La system are investigated by means of microstructural and differential thermal analysis. Existence of LaCu 2 Al 10 and LaCu 0.5 Al 3.5 ternary compounds in the system is confirmed and it is shown, as well, both compounds are in two-phase equilibrium with aluminium solid solution and form with it and between each other eutectic type state diagrams. State diagrams for quasibinary sections are plotted

Elastic and plastic properties of iron-aluminium alloys. Special problems raised by the brittleness of alloys of high aluminium content

International Nuclear Information System (INIS)

Mouturat, P.

1966-06-01

The present study embodies the results obtained with iron-aluminium alloys whose composition runs from 0 to nearly 50 atoms per cent aluminium. Conditions of elaboration and transformation have been studied successively, as well as the Young's modulus and the flow stress; the last chapter embodies, a study of the Portevin-le-Chatelier effect in alloys of 40 atoms per cent of aluminium. I) The principal difficulty to clear up consisted in the intergranular brittleness of ordered alloys; this brittleness has been considerably reduced with appropriate conditions of elaboration and transformation. II) The studies upon the Young's modulus are in connection with iron-aluminium alloys; transformation temperatures are well shown up. The formation of covalent bonds on and after 25 atoms per cent show the highest values of the modulus. III) The analysis of variations of the flow stress according to the temperature show some connection with ordered structures, the existence of antiphase domains and the existence of sur-structure dislocations. IV) In the ordered Fe Al domain the kinetics of the Portevin-le-Chatelier effect could be explained by a mechanism of diffusion of vacancies. The role they play has been specified by the influence they exert upon the dislocations; this has led us to the inhomogeneous Rudman order; this inhomogeneous order could explain the shape of the traction curves. (author) [fr

Performance of Electrocoagulation Process for Removal of Sulphate Ion from Aqueous Environments Using Plate Aluminum Electrodes

Directory of Open Access Journals (Sweden)

a.h Mahvi

2012-05-01

Full Text Available

Background and Objectives: Sulphate ion is one of the main ions available in natural and waste water. The high rate of sulphate in drinking water causes health problems such as irritation and digestive problems and makes water taste bitter. The purpose of this study was to assess the efficiency of sulphate ion removal from drinking water through Electrocogualation process (EC using plate aluminum electrodes. Methods: This study was conducted as a pilot plant using one glass tank in the volume of 1.3liter containing 6 plate aluminum electrodes. These electrodes were attached to a power supply in a mono-polar and parallel arrangement in order to switch the alternating current to the direct one. That is, each electrode was attached to positive and negative poles directly and alternately. The tank was filled with synthetic water containing sulphate ion with the concentration of 350 & 700mg/L. Percentage of sulphate ion removal in potential range of 10, 20 and 30 V, reaction times of 40, 20 and 60min and pH 7.0, 3.0 & 11.0 were measured. Results: In this study the maximum efficiency of sulphate ion removal was in the electrical potential of 30 V, reaction time of 60min and pH 11.0. With increase of ion concentration, the time needed to achieve a suitable efficiency of removal increased, that is, it indicated the direct effect of pH and difference of electrical potential on removal of sulphate ion through EC process. Conclusion: The results of this research show that Electrocogualation technology can be introduced as a suitable and promising technique to remove sulphate ion from aqueous environments using plate aluminum electrodes.

Performance of Electrocoagulation Process for Removal of Sulphate Ion from Aqueous Environments Using Plate Aluminum Electrodes

Directory of Open Access Journals (Sweden)

Rajabizadeh A.

2010-09-01

Full Text Available Background and Objectives: Sulphate ion is one of the main ions available in natural and waste water. The high rate of sulphate in drinking water causes health problems such as irritation and digestive problems and makes water taste bitter. The purpose of this study was to assess the efficiency of sulphate ion removal from drinking water through Electrocogualation process (EC using plate aluminum electrodes.Methods: This study was conducted as a pilot plant using one glass tank in the volume of 1.3liter containing 6 plate aluminum electrodes. These electrodes were attached to a power supply in a mono-polar and parallel arrangement in order to switch the alternating current to the direct one. That is, each electrode was attached to positive and negative poles directly and alternately. The tank was filled with synthetic water containing sulphate ion with the concentration of 350 & 700mg/L. Percentage of sulphate ion removal in potential range of 10, 20 and 30 V, reaction times of 40, 20 and 60min and pH 7.0, 3.0 & 11.0 were measured.Results: In this study the maximum efficiency of sulphate ion removal was in the electrical potential of 30 V, reaction time of 60min and pH 11.0. With increase of ion concentration, the time needed to achieve a suitable efficiency of removal increased, that is, it indicated the direct effect of pH and difference of electrical potential on removal of sulphate ion through EC process.Conclusion: The results of this research show that Electrocogualation technology can be introduced as a suitable and promising technique to remove sulphate ion from aqueous environments using plate aluminum electrodes.

Sulphate Potasium Extraction From Banana Stem Ash with Bleaching Earth Waste Liquid

OpenAIRE

Edahwati, Luluk

2010-01-01

Sulphate potassium is one of the important chemistry compound for industrial at our country, usually for fertilizerindustry. Therefore, necessary done sulphate potassium maker watchfulness from various ingredient that containsulphate potassium compound. Among others with extract banana stem ash. Watchfulness methodology that is withmix banana stem ash with aquadest (20 gram ash/1 water litre) in temperature 100oc during 30 minutes and stirringrotation 300 rpm. Ash extract that got reaction wi...

Impact properties of aluminium - glass fiber reinforced plastics sandwich panels

Directory of Open Access Journals (Sweden)

Mathivanan Periasamy

2012-06-01

Full Text Available Aluminium - glass fiber reinforced plastics (GFRP sandwich panels are hybrid laminates consisting of GFRP bonded with thin aluminum sheets on either side. Such sandwich materials are increasingly used in airplane and automobile structures. Laminates with varying aluminium thickness fractions, fiber volume fractions and orientation in the layers of GFRP were fabricated by hand lay up method and evaluated for their impact performance by conducting drop weight tests under low velocity impacts. The impact energy required for initiating a crack in the outer aluminium layer as well as the energy required for perforation was recorded. The impact load-time history was also recorded to understand the failure behavior. The damage depth and the damage area were measured to evaluate the impact resistance. Optical photography and scanning electron micrographs were taken to visualize the crack and the damage zone. The bidirectional cross-ply hybrid laminate (CPHL has been found to exhibit better impact performance and damage resistance than the unidirectional hybrid laminate (UDHL. Increase in aluminium thickness fraction (Al tf and fiber volume fraction (Vf resulted in an increase in the impact energy required for cracking and perforation. On an overall basis, the sandwich panels exhibited better impact performance than the monolithic aluminium.

Toxicology studies of primycin-sulphate using a three-dimensional (3D) in vitro human liver aggregate model.

Science.gov (United States)

Pénzes, Ágota; Mahmud Abdelwahab, Elhusseiny Mohamed; Rapp, Judit; Péteri, Zsanett A; Bovári-Biri, Judit; Fekete, Csaba; Miskei, György; Kvell, Krisztián; Pongrácz, Judit E

2017-11-05

Primycin-sulphate is a highly effective compound against Gram (G) positive bacteria. It has a potentially synergistic effect with vancomycin and statins which makes primycin-sulphate a potentially very effective preparation. Primycin-sulphate is currently used exclusively in topical preparations. In vitro animal hepatocyte and neuromuscular junction studies (in mice, rats, snakes, frogs) as well as in in vitro human red blood cell experiments were used to test toxicity. During these studies, the use of primycin-sulphate resulted in reduced cellular membrane integrity and modified ion channel activity. Additionally, parenteral administration of primycin-sulphate to mice, dogs, cats, rabbits and guinea pigs indicated high level of acute toxicity. The objective of this study was to reveal the cytotoxic and gene expression modifying effects of primycin-sulphate in a human system using an in vitro, three dimensional (3D) human hepatic model system. Within the 3D model, primycin-sulphate presented no acute cytotoxicity at concentrations 1μg/ml and below. However, even at low concentrations, primycin-sulphate affected gene expressions by up-regulating inflammatory cytokines (e.g., IL6), chemokines (e.g., CXCL5) and by down-regulating molecules of the lipid metabolism (e.g., peroxisome proliferator receptor (PPAR) alpha, gamma, etc). Down-regulation of PPAR alpha cannot just disrupt lipid production but can also affect cytochrome P450 metabolic enzyme (CYP) 3A4 expression, highlighting the need for extensive drug-drug interaction (DDI) studies before human oral or parenteral preparations can be developed. Copyright © 2017 Elsevier B.V. All rights reserved.

Photodynamic effect of aluminium and zinc tetrasulfophthalocyanines on melanoma cancer cells

CSIR Research Space (South Africa)

Maduray, K

2010-06-01

Full Text Available Aluminium and zinc tetrasulfophthalocyanines were activated with a 672nm wavelength laser to investigate the photodynamic effects on melanoma cancer, dermal fibroblast and epidermal keratinocyte cells. Aluminium tetrasulfophthalocyanine was more...

Effects of Manganese (Ii Sulphate on Structural, Spectral, Optical, Thermal and Mechanical Properties of L-Alanine Sodium Sulphate Single Crystals

Directory of Open Access Journals (Sweden)

F. Praveena

2017-04-01

Full Text Available New Non-linear Optical materials have been attracting in the research world for their potential applications in emerging opto-electronic technology. The dipolar nature of amino acid leads to peculiar physical and chemical properties, thus making a good candidate for NLO applications. Single crystals of manganese(II sulphate doped L-Alanine sodium sulphate(LASS has been synthesized by slow evaporation technique. Structural property of the grown crystals are characterized by X-ray powder diffraction,FT-IR spectral analysis conforms all the functional groups. Thermogravity (TG and differential themogravimetric (DTA analysis have been performed to study the thermal stability of the crystals. The second harmonic generation efficiency was measured by Kurtz-Perry powder technique. The transmission and absorption of electromagnetic radiation is analysed through UV-VIS spectrum. Microhardness was measured at different applied load to understand the mechanical stability of the crystal.

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

Science.gov (United States)

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

2013-11-01

Aluminium oxyhydroxide, Al(OH)3 is one of few compounds approved as an adjuvant in human vaccines. However, the mechanism behind its immune stimulating properties is still poorly understood. In vitro co-culture of an aluminium adjuvant and the human monocytic cell line THP-1 resulted in reduced cell proliferation. Inhibition occurred at concentrations of adjuvant several times lower than would be found at the injection site using a vaccine formulation containing an aluminium adjuvant. Based on evaluation of the mitochondrial membrane potential, THP-1 cells showed no mitochondrial rupture after co-culture with the aluminium adjuvant, instead an increase in mitochondrial activity was seen. The THP-1 cells are phagocytosing cells and after co-culture with the aluminium adjuvant the phagosomal pathway was obstructed. Primary or early phagosomes mature into phagolysosomes with an internal pH of 4.5 - 5 and carry a wide variety of hydrolysing enzymes. Co-culture with the aluminium adjuvant yielded a reduced level of acidic vesicles and cathepsin L activity, a proteolytic enzyme of the phagolysosomes, was almost completely inhibited. THP-1 cells are an appropriate in vitro model in order to investigate the mechanism behind the induction of a phagocytosing antigen presenting cell into an inflammatory cell by aluminium adjuvants. Much information will be gained by investigating the phagosomal pathway and what occurs inside the phagosomes and to elucidate the ultimate fate of phagocytosed aluminium particles. © 2013.

Evaluating portland cement concrete degradation by sulphate exposure through artificial neural networks modeling

International Nuclear Information System (INIS)

Oliveira, Douglas Nunes de; Bourguignon, Lucas Gabriel Garcia; Tolentino, Evandro; Costa, Rodrigo Moyses; Tello, Cledola Cassia Oliveira de

2015-01-01

A concrete is durable if it has accomplished the desired service life in the environment in which it is exposed. The durability of concrete materials can be limited as a result of adverse performance of its cement-paste matrix or aggregate constituents under either chemical or physical attack. Among other aggressive chemical exposures, the sulphate attack is an important concern. Water, soils and gases, which contain sulphate, represent a potential threat to the durability of concrete structures. Sulphate attack in concrete leads to the conversion of the hydration products of cement to ettringite, gypsum, and other phases, and also it leads to the destabilization of the primary strength generating calcium silicate hydrate (C-S-H) gel. The formation of ettringite and gypsum is common in cementitious systems exposed to most types of sulphate solutions. The present work presents the application of the neural networks for estimating deterioration of various concrete mixtures due to exposure to sulphate solutions. A neural networks model was constructed, trained and tested using the available database. In general, artificial neural networks could be successfully used in function approximation problems in order to approach the data generation function. Once data generation function is known, artificial neural network structure is tested using data not presented to the network during training. This paper is intent to provide the technical requirements related to the production of a durable concrete to be used in the structures of the Brazilian near-surface repository of radioactive wastes. (author)

Biotreatment of Cr(VI) contaminated waters by sulphate reducing bacteria fed with ethanol

Energy Technology Data Exchange (ETDEWEB)

Pagnanelli, F., E-mail: francesca.pagnanelli@uniroma1.it [Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome (Italy); Cruz Viggi, C., E-mail: carolina.cruzviggi@uniroma1.it [Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome (Italy); Cibati, A., E-mail: alessio.cibati@uniroma1.it [Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome (Italy); Uccelletti, D., E-mail: daniela.uccelletti@uniroma1.it [Department of Biology and Biotechnology, Sapienza University of Rome, P.le A. Moro 5, 00185 Rome (Italy); Toro, L., E-mail: luigi.toro@uniroma1.it [Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome (Italy); Palleschi, C., E-mail: claudio.palleschi@uniroma1.it [Department of Biology and Biotechnology, Sapienza University of Rome, P.le A. Moro 5, 00185 Rome (Italy)

2012-01-15

Highlights: Black-Right-Pointing-Pointer Use of ethanol as electron donor for sulphate-reducing bacteria for the treatment of Cr(VI). Black-Right-Pointing-Pointer Isolation of contribution in Cr removal (adsorption vs. bioprecipitation). Black-Right-Pointing-Pointer Bioassessment of the process effectiveness by ecotoxicological in vivo tests using C. elegans. - Abstract: Biological treatment of Cr(VI) contaminated waters was performed in fixed bed reactors inoculated with SRB (sulphate-reducing bacteria) growing on ethanol. Treatment efficiency was evaluated by checking chemical abatement of Cr(VI) and by ecotoxicological tests using the nematode Caenorhabditis elegans. A preliminary comparison between ethanol and lactate was performed, denoting that using ethanol, the same values of final sulphate abatement were obtained. In addition ethanol showed to be a substrate more competitive than lactate in kinetic terms. Fixed bed column reactors were continuously fed with a solution containing sulphates (3 g L{sup -1}), ethanol (1.5 g L{sup -1}) and Cr(VI) (50 mg L{sup -1}). At steady state the column inoculated with SRB removed 65 {+-} 5% of sulphate and 95 {+-} 5% of chromium. Bioactive removal mechanisms predominated over biosorption. Diminution of Cr(VI) toxicity was assessed by using the nematode C. elegans as a test organism showing that the survival of nematodes was 20% in the presence of the untreated influent and raised up to 53% when the nematodes were exposed to the treated effluent.

Evaluating portland cement concrete degradation by sulphate exposure through artificial neural networks modeling

Energy Technology Data Exchange (ETDEWEB)

Oliveira, Douglas Nunes de; Bourguignon, Lucas Gabriel Garcia; Tolentino, Evandro, E-mail: tolentino@timoteo.cefetmg.br [Centro Federal de Educacao Tecnologica de Minas Gerais (CEFET-MG), Timoteo, MG (Brazil); Costa, Rodrigo Moyses, E-mail: rodrigo@moyses.com.br [Universidade de Itauna, Itauna, MG (Brazil); Tello, Cledola Cassia Oliveira de, E-mail: tellocc@cdtn.br [Centro de Desenvolvimento da Tecnologia Nucelar (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2015-07-01

A concrete is durable if it has accomplished the desired service life in the environment in which it is exposed. The durability of concrete materials can be limited as a result of adverse performance of its cement-paste matrix or aggregate constituents under either chemical or physical attack. Among other aggressive chemical exposures, the sulphate attack is an important concern. Water, soils and gases, which contain sulphate, represent a potential threat to the durability of concrete structures. Sulphate attack in concrete leads to the conversion of the hydration products of cement to ettringite, gypsum, and other phases, and also it leads to the destabilization of the primary strength generating calcium silicate hydrate (C-S-H) gel. The formation of ettringite and gypsum is common in cementitious systems exposed to most types of sulphate solutions. The present work presents the application of the neural networks for estimating deterioration of various concrete mixtures due to exposure to sulphate solutions. A neural networks model was constructed, trained and tested using the available database. In general, artificial neural networks could be successfully used in function approximation problems in order to approach the data generation function. Once data generation function is known, artificial neural network structure is tested using data not presented to the network during training. This paper is intent to provide the technical requirements related to the production of a durable concrete to be used in the structures of the Brazilian near-surface repository of radioactive wastes. (author)

Numerical/experimental research on welded joints in aluminium truss girders

NARCIS (Netherlands)

van Hove, B.W.E.M.; Soetens, F.; Mazzolani, F.M.; Bellucci, F.; Faggiano, B.; Squillace, A.

2016-01-01

Welded joints in a 30 meter span aluminium truss girder were investigated numerically and experimentally. Since aluminium design rules for welded K-and N-joints in CHS truss girders were lacking the joints were checked using steel design rules. Calculations showed that the N-joints were governing

Hexagonal ZnO porous plates prepared from microwave synthesized layered zinc hydroxide sulphate via thermal decomposition

Energy Technology Data Exchange (ETDEWEB)

Machovsky, Michal, E-mail: machovsky@ft.utb.cz [Centre of Polymer Systems, University Institute, Tomas Bata University in Zlin, Nad Ovcirnou 3685, 760 01 Zlin (Czech Republic); Polymer Centre, Faculty of Technology, Tomas Bata University in Zlin, Nam. T.G. Masaryka 275, 762 72 Zlin (Czech Republic); Kuritka, Ivo, E-mail: ivo@kuritka.net [Centre of Polymer Systems, University Institute, Tomas Bata University in Zlin, Nad Ovcirnou 3685, 760 01 Zlin (Czech Republic); Polymer Centre, Faculty of Technology, Tomas Bata University in Zlin, Nam. T.G. Masaryka 275, 762 72 Zlin (Czech Republic); Sedlak, Jakub, E-mail: j1sedlak@ft.utb.cz [Centre of Polymer Systems, University Institute, Tomas Bata University in Zlin, Nad Ovcirnou 3685, 760 01 Zlin (Czech Republic); Polymer Centre, Faculty of Technology, Tomas Bata University in Zlin, Nam. T.G. Masaryka 275, 762 72 Zlin (Czech Republic); Pastorek, Miroslav, E-mail: pastorek@ft.utb.cz [Centre of Polymer Systems, University Institute, Tomas Bata University in Zlin, Nad Ovcirnou 3685, 760 01 Zlin (Czech Republic); Department of Polymer Engineering, Faculty of Technology, Tomas Bata University in Zlin, Nam. T.G. Masaryka 275, 762 72 Zlin (Czech Republic)

2013-10-15

Graphical abstract: - Highlights: • Zinc hydroxy sulphate was synthesized in 3 min via microwave hydrothermal route. • Zinc hydroxy sulphate was converted into mesh like porous ZnO by calcining at 900°. • The process of transformation is topotactic. - Abstract: Layered zinc hydroxide sulphate (ZHS) was prepared by microwave-assisted hydrothermal precipitation of zinc sulphate monohydrate with hexamethylenetetramine. Under ambient conditions, the structure of ZHS determined by X-ray diffraction (XRD) was found to be a mixture of zinc hydroxide sulphate pentahydrate Zn{sub 4}SO{sub 4}(OH){sub 6}·5H{sub 2}O and tetrahydrate Zn{sub 4}SO{sub 4}(OH){sub 6}·4H{sub 2}O. Fourier transform infrared (FTIR) spectroscopy was used for characterization of the prepared materials. Based on the interpretation of ZHS's thermal decomposition profile obtained by thermogravimetric analysis, ZnO of high purity was prepared by calcination at 900 °C for 2 h. The structure of the resulting ZnO was confirmed by the XRD. The morphology examination by scanning electron microscopy revealed a porous mesh-like ZnO structure developed from the ZHS precursor at the expense of mass removal due to the release of water and sulphate during the calcination.

Intoxication experiments with beryllium sulphate

International Nuclear Information System (INIS)

Bucurescu, I.; Stan, T.

1990-01-01

The changes in the particular number of animals in two groups of 40 rats each subjected to intoxication experiments with beryllium sulphate was investigated. The two investigations had very different characteristics. In the case of chronic intoxication there was a marked lethality over given time intervals. In the case of subacute intoxication the number of animals decreased with time. It was found empirically that this change can be described by an exponential relationship which lends itself to statistical interpretation. (author)

Numerical modelling of closed-cell aluminium foam under dynamic loading

Science.gov (United States)

Hazell, Paul; Kader, M. A.; Islam, M. A.; Escobedo, J. P.; Saadatfar, M.

2015-06-01

Closed-cell aluminium foams are extensively used in aerospace and automobile industries. The understanding of their behaviour under impact loading conditions is extremely important since impact problems are directly related to design of these engineering structures. This research investigates the response of a closed-cell aluminium foam (CYMAT) subjected to dynamic loading using the finite element software ABAQUS/explicit. The aim of this research is to numerically investigate the material and structural properties of closed-cell aluminium foam under impact loading conditions with interest in shock propagation and its effects on cell wall deformation. A μ-CT based 3D foam geometry is developed to simulate the local cell collapse behaviours. A number of numerical techniques are applied for modelling the crush behaviour of aluminium foam to obtain the more accurate results. The simulation results are compared with experimental data. Comparison of the results shows a good correlation between the experimental results and numerical predictions.

Comparison of methods for the determination of reduced inorganic sulphur in acid sulphate soils

International Nuclear Information System (INIS)

Santomartino, S.L.

1999-01-01

Full text: The management of acid sulphate soils requires analytical methods that provide accurate data on the quantity of reduced inorganic sulphur within a soil, as it is this fraction that produces acid upon oxidation. This study uses sulphidic Coode Island Silt samples to compare common analytical methods including POCAS (Peroxide Oxidation-Combined Acidity and Sulphate) which consists of TSA (Total Sulphidic Acidity), S pos (Peroxide Oxidisable Sulphur), TOS (Total Oxidisable Sulphur) and chromium-reducible sulphur. The determination of total sulphur by Leco sulphur is strongly correlated with, but slightly less than, that analysed by XRF. Comparison of soil sulphide content by chromium-reducible sulphur, TSA and TOS methods indicates that TOS values are substantially higher than both other methods. The problem with the TOS method lies in the sulphate extraction procedure. Hot distilled water and HCI are commonly used as extractants, however hot distilled water fails to remove organic sulphur, thereby overestimating the sulphide content of the soil. Leco carbon analyses verify that a substantial proportion of organic matter exists within the samples. The HCI extraction process, which uses Ion Chromatography to analyse for sulphate, produces highly inaccurate results due to the interference of the sulphate peak by the chloride peak during analysis. An alternative method involving HCI extraction and XRF analysis of the soil residue is currently being undertaken. The use of KCI to extract sulphate generally produces values similar to the hot distilled water method. The sulphidic content measured by TSA is strongly correlated with, but slightly higher than that determined by the chromium-reducible sulphur method. This is attributed to the use of hydrogen peroxide in the TSA method, which oxidises organic matter to organic acids in addition to oxidising sulphides. These preliminary findings indicate that the chromium-reducible sulphur method is the most suitable

"INHIBITORY EFFECT OF ALUMINIUM ON KCL AND PHENYLEPHRINE INDUCED CONTRACTION IN ISOLATED RAT AORTA"

Directory of Open Access Journals (Sweden)

T. Mashhoodi

2004-10-01

Full Text Available It has been shown in some investigations that cardiovascular events are the main causes of death in hemodialysis patients. The exact etiology is unknown but some of the articles have reported a relation between aluminium ions in the dialysis solution and cardiovascular disorders. To determine the probable effect of aluminium on vasculature function, in vitro effects of aluminium ion on vasoconstriction induced by KCl (30 mM or phenylephrine (10 µM were investigated using isolated rat aorta. AlCl3 (1-4 mM decreased both KCl and phenylephrine induced contractions in a dose dependent manner (P<0.01. Complete inhibition of the contractions occurred using the higher doses of aluminium. Results of this study suggest that because of inhibitory effects of aluminium on vascular contractions, the probable cardiovascular dysfunction must be considered in aluminium intoxication.

Thermodynamic properties of uranium in gallium–aluminium based alloys

International Nuclear Information System (INIS)

Volkovich, V.A.; Maltsev, D.S.; Yamshchikov, L.F.; Chukin, A.V.; Smolenski, V.V.; Novoselova, A.V.; Osipenko, A.G.

2015-01-01

Activity, activity coefficients and solubility of uranium was determined in gallium-aluminium alloys containing 1.6 (eutectic), 5 and 20 wt.% aluminium. Additionally, activity of uranium was determined in aluminium and Ga–Al alloys containing 0.014–20 wt.% Al. Experiments were performed up to 1073 K. Intermetallic compounds formed in the alloys were characterized by X-ray diffraction. Partial and excess thermodynamic functions of U in the studied alloys were calculated. - Highlights: • Thermodynamics of uranium is determined in Ga–Al alloys of various compositions. • Uranium in the mixed alloys interacts with both components, Ga and Al. • Interaction of U with Al increases with decreasing temperature. • Activity and solubility of uranium depend on Al content in Ga–Al alloys.

Thermodynamic properties of uranium in gallium–aluminium based alloys

Energy Technology Data Exchange (ETDEWEB)

Volkovich, V.A., E-mail: v.a.volkovich@urfu.ru [Department of Rare Metals and Nanomaterials, Institute of Physics and Technology, Ural Federal University, Ekaterinburg, 620002 (Russian Federation); Maltsev, D.S.; Yamshchikov, L.F. [Department of Rare Metals and Nanomaterials, Institute of Physics and Technology, Ural Federal University, Ekaterinburg, 620002 (Russian Federation); Chukin, A.V. [Department of Theoretical Physics and Applied Mathematics, Institute of Physics and Technology, Ural Federal University, Ekaterinburg, 620002 (Russian Federation); Smolenski, V.V.; Novoselova, A.V. [Institute of High-Temperature Electrochemistry UD RAS, Ekaterinburg, 620137 (Russian Federation); Osipenko, A.G. [JSC “State Scientific Centre - Research Institute of Atomic Reactors”, Dimitrovgrad, 433510 (Russian Federation)

2015-10-15

Activity, activity coefficients and solubility of uranium was determined in gallium-aluminium alloys containing 1.6 (eutectic), 5 and 20 wt.% aluminium. Additionally, activity of uranium was determined in aluminium and Ga–Al alloys containing 0.014–20 wt.% Al. Experiments were performed up to 1073 K. Intermetallic compounds formed in the alloys were characterized by X-ray diffraction. Partial and excess thermodynamic functions of U in the studied alloys were calculated. - Highlights: • Thermodynamics of uranium is determined in Ga–Al alloys of various compositions. • Uranium in the mixed alloys interacts with both components, Ga and Al. • Interaction of U with Al increases with decreasing temperature. • Activity and solubility of uranium depend on Al content in Ga–Al alloys.

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

Science.gov (United States)

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

2013-04-07

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.

Different Approach to the Aluminium Oxide Topography Characterisation

International Nuclear Information System (INIS)

Poljacek, Sanja Mahovic; Gojo, Miroslav; Raos, Pero; Stoic, Antun

2007-01-01

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

Quantitative electron probe microanalysis of borides in aluminium

International Nuclear Information System (INIS)

Karduck, P.; Schuerhoff, H.J.; Burchard, W.G.

1983-01-01

A procedure for the quantitative analysis of borides in aluminium was introduced. For this purpose the optimal apparative boundary conditions for the EPMA of boron were worked out. With these conditions a satisfactory peak to background ratio of 57 could be achieved for B-Kα-radiation. By application of this method the following conclusion should be drawn concerning the kind of nuclei during grain refinement of aluminium with titanium and boron: For grain refinement of aluminium with titanium and boron in the hypoperitectic region of the binary system Al-Ti TiB 2 -particles in clusters provide the high efficiency of refinement. This entails that the TiB 2 -particles already present in the master alloy remain inert in the melt. Hence, the good efficiency of refinement in this region cannot be attributed to the presence of particles like Al 3 Ti, AlB 2 or (Al, Ti) B 2 . (Author)

Determinants of magnesium sulphate use in women hospitalized at <29 weeks with severe or non-severe pre-eclampsia.

Directory of Open Access Journals (Sweden)

Dane A De Silva

Full Text Available Magnesium sulphate is recommended by international guidelines to prevent eclampsia among women with pre-eclampsia, especially when it is severe, but fewer than 70% of such women receive magnesium sulphate. We aimed to identify variables that prompt Canadian physicians to administer magnesium sulphate to women with pre-eclampsia.Data were used from the Canadian Perinatal Network (2005-11 of women hospitalized at <29 weeks' who were thought to be at high risk of delivery due to pre-eclampsia (using broad Canadian definition. Unadjusted analyses of relative risks were estimated directly and population attributable risk percent (PAR% calculated to identify variables associated with magnesium sulphate use. A multivariable model was created and a generalized estimating equation was used to estimate the adjusted RR that explained magnesium sulphate use in pre-eclampsia. The adjusted PAR% was estimated by bootstrapping.Of 631 women with pre-eclampsia, 174 (30.1% had severe pre-eclampsia, of whom 131 (75.3% received magnesium sulphate. 457 (69.9% women had non-severe pre-eclamspia, of whom 291 (63.7% received magnesium sulphate. Use of magnesium sulphate among women with pre-eclampsia could be attributed to the following clinical factors (PAR%: delivery for 'adverse conditions' (48.7%, severe hypertension (21.9%, receipt of antenatal corticosteroids (20.0%, maternal transport prior to delivery (9.9%, heavy proteinuria (7.8%, and interventionist care (3.4%.Clinicians are more likely to administer magnesium sulphate for eclampsia prophylaxis in the presence of more severe maternal clinical features, in addition to concomitant antenatal corticosteroid administration, and shorter admission to delivery periods related to transport from another institution or plans for interventionist care.

Green chemical incorporation of sulphate into polyoxoanions of ...

Indian Academy of Sciences (India)

Green chemical incorporation of sulphate into polyoxoanions of molybdenum to nano level ... Keywords. Polyoxometalate; green synthesis; nanostructures; surfactant. ... The effects of reaction parameters such as concentration of surfactant, temperature and pH of solution on the synthesis of nanospheres were investigated.

Aluminium - Cobalt-Pillared Clay for Dye Filtration Membrane

Science.gov (United States)

Darmawan, A.; Widiarsih

2018-04-01

The manufacture of membrane support from cobalt aluminium pillared clay has been conducted. This research was conducted by mixing a clay suspension with pillared solution prepared from the mixture of Co(NO3)2.6H2O and AlCl3.6H2O. The molar ratio between Al and Co was 75:25 and the ratio of [OH-]/[metal] was 2. The clay suspension was stirred for 24 hours at room temperature, filtered and dried. The dried clay was then calcined at 200°C, 300°C and 400°C with a ramp rate of 2°C/min. Aluminium-cobalt-pillared clay was then characterized by XRD and GSA and moulded become a membrane support for subsequent tests on dye filtration. The XRD analysis showed that basal spacing (d 001) value of aluminium cobalt was 19.49 Å, which was higher than the natural clay of 15.08Å however, the basal spacing decreased with increasing calcination temperature. The result of the GSA analysis showed that the pore diameter of the aluminium cobalt pillared clay membrane was almost the same as that of natural clay that were 34.5Å and 34.2Å, respectively. Nevertheless, the pillared clay has a more uniform pore size distribution. The results of methylene blue filtration measurements demonstrated that the membrane filter support could well which shown by a clear filtrate at all concentrations tested. The value of rejection and flux decreased with the increasing concentration of methylene blue. The values of dye rejection and water flux reached 99.89% and 5. 80 x 10-6 kg min-1, respectively but they decreased with increasing concentration of methylene blue. The results of this study indicates that the aluminium-pillared clay cobalt could be used as membrane materials especially for ultrafiltration.

Combined Corrosion and Wear of Aluminium Alloy 7075-T6

NARCIS (Netherlands)

Liu, Y.; Mol, J.M.C.; Janssen, G.C.A.M.

2016-01-01

The aluminium alloy 7075-T6 is widely used in engineering. In some applications, like slurry transport, corrosion and abrasion occur simultaneously, resulting in early material failure. In the present work, we investigated the combined effect of corrosion and wear on the aluminium alloy 7075-T6. We

Grain Refinement of Commercial EC Grade 1070 Aluminium Alloy for Electrical Application

OpenAIRE

Hassanabadi, Massoud

2015-01-01

The aluminium alloys for electrical conductivity applications are generally not grain refinedsince the addition of grain refiners drops the electrical conductivity by introducing impuritiesinto the melt. Non-grain refined aluminium may lead to bar fracture and cracks during themetalworking process. The present study focuses to find an optimum balance between the grain refiner addition andthe electrical conductivity of commercial EC grade 1070 aluminium alloy for electricalapplication. In orde...

Development of microstructure during sintering and aluminium exposure of titanium diboride ceramics

Energy Technology Data Exchange (ETDEWEB)

Pettersen, Gunnar

1997-12-31

In the production of aluminium, much less energy need be consumed if an inert, wetted cathode is present in the electrolysis cell. Titanium diboride, TiB{sub 2}, is easily wetted and does not readily dissolve in liquid aluminium, but it degrades, probably because aluminium penetrates into it during electrolysis. This degradation is linked to impurities present in the TiB{sub 2} after sintering. This thesis studies the sintering process and how aluminium penetrates into the material. High-purity, high-density TiB{sub 2} compacts were made by hot pressing at 50 MPa in an argon atmosphere at 1790-1960 {sup o}C. Samples were made with different impurity additions. These samples were exposed to liquid aluminium at 980 {sup o}C for 24 hours. All samples were penetrated, but the amount and appearance depended on the sintering aid used. Unlike the other samples, pure TiB{sub 2} was easily penetrated by metallic aluminium because of the open porosity and microcracks of this material. Grain boundary penetration was common among the samples. Differences in penetration behaviour between grain boundaries are probably due to differences in grain boundary energy. But no relation to segregants or boundary misorientation was found. The orientation of grain boundary planes and de-wetting of thin films upon cooling may explain the observed microstructure development. The samples sintered with Ti addition suffered extensive penetration despite their high densities. The grain boundaries of these samples became faceted and contained thicker films of metallic aluminium, presumably because of increased solubility due to iron segregations. All secondary phases present in the grain junctions after sintering, except from the B{sub 4}C phase, reacted with the penetrated aluminium. This did not cause swelling and cracking, as has been suggested by other authors. 101 refs., 48 figs., 7 tabs.

Analgesic effect of intra-articular magnesium sulphate compared with bupivacaine after knee arthroscopic menisectomy

Directory of Open Access Journals (Sweden)

Yasser A. Radwan

2013-07-01

Full Text Available This work aimed to evaluate the analgesic efficacy of intra-articular injection of magnesium sulphate (4% compared with equivalent volume of bupivacaine (0.5% after outpatient knee arthroscopic meniscectomy. Forty patients were randomly assigned to two groups. Group M (n = 20 received intra-articular magnesium sulphate 4%, group B (n = 20 received bupivacaine (0.5%. Analgesic effect was evaluated by analgesic duration, and by measuring pain intensity at 1, 2, 4, 6, 12, 24 h both at rest and on knee movement to 90°. The primary outcome variable was pain intensity on the VAS at 1, 2, 4, 6, 12, 24 h post arthroscopy at rest and on movement (flexion of knee to 90°, although the magnesium group had lower time weighted averages (TWAs at rest and on movement, these TWAs were not statistically significant. The median duration of postoperative analgesia was significantly longer in the patients treated with magnesium sulphate (528 min than in the bupivacaine group (317 min (p < 0.0001, with less number of patients needing supplementary analgesia in magnesium group (8/20 than those of the bupivacaine group (16/20 (p < 0.022. Also analgesic consumption was significantly lower in the magnesium sulphate group (p < 0.002. We concluded that the use of magnesium sulphate is rational and effective in reducing pain, and is more physiological and shortens convalescence after outpatient arthroscopic meniscectomy, however our hypotheses that analgesic efficacy of intra-articular isotonic magnesium sulphate would be superior to intra-articular local anaesthetic cannot be supported with this study.

Effect of Microbial inoculation in combating the aluminium toxicity effect on growth of Zea mays.

Science.gov (United States)

Arora, P; Singh, G; Tiwari, A

2017-07-31

The present study is aimed at improving the aluminium tolerance in maize crop employing the potential of microbial inoculants in conferring resistance to these toxicities via production of certain chelating compounds like siderophores, exopolysachharides and organic acids. Acid soils have now-a-days become one of the key factors for limiting growth of many agriculturally important crops. Aluminium  is one of the major elements present in acid soils and is mainly responsible for toxicity in the soil. This aluminium is rapidly soluble in soil water and hence absorbed by plant roots under conditions where soil pH is below 5. This toxicity leads to severe root growth inhibition, thereby limiting the production of maize crops. It was observed that use of microbial inoculums can be helpful in elimination of these toxic compounds and prevent the inhibition of root growth . It was found that the soils contaminated with aluminium toxicity decreased the root length of maize plant significantly by 65% but Bacillus and Burkholderia inoculation increased this root length significantly by 1.4- folds and 2- folds respectively thereby combating the effect of aluminium toxicity. Aluminium concentration was found maximum in roots of plants which were grown under aluminium stress condition. But this aluminium accumulation decreased ̴ 2-folds when Burkholderia was used as seed inoculants under aluminium stress conditions. Also, at 60mM aluminium accumulation, phosphorus solubilisation in roots was found to be increased upto 30% on Burkholderia inoculation. However, Bacillus inoculation didn't show any significant difference in either of the case. Thus, the inoculation of seeds with Burkholderia isolates could prove to be a boon in sequestering aluminium toxicity in Zea mays.

The impact of acid sulphate soils on water bodies and fish deaths in Finland; Happamien sulfaattimaiden aiheuttamat vesistoevaikutukset ja kalakuolemat Suomessa

Energy Technology Data Exchange (ETDEWEB)

Sutela, T.; Vuori, K.-M.; Louhi, P. [and others

2012-05-15

We have compiled in this review a comprehensive presentation of the impacts of acid sulphate soils (ASS) on water quality, biota, and fish kills in Finnish water bodies. This review is a result of extensive collaboration among research scientists in connection with the CATERMASS project co-ordinated by the Finnish Environment Institute (SYKE). Acid sulphate soils were formed in the eutrophic coastal waters of the Baltic Sea 4,000-8,000 years ago as microbes reduced the sulphate contained in saline seawater into sulphide. Sulphide clay soils emerging through land uplift have since been reclaimed and drained for cultivation use. Sulphur released in the resultant oxidation process reacted with soil water to form sulphuric acid, which draws toxic metals such as aluminium, cadmium, and copper from the soil. Heavy rains and the waters of springtime thawing transported acids and metals to the water bodies. In recent decades, the drainage depth of fields has increased because of the growing popularity of subterranean drainage methods, thus exacerbating the adverse ASS impacts on water bodies. Acidity and the attendant proliferation of toxic forms of metals induce changes in all organism groups of water biota, among them fish, macroinvertebrates, macrophytes, and bottom algae. On the specimen level, malformations have been discovered, such as structural pupae impairment in aquatic insects. The defence mechanism employed by fish against harmful substances in the surrounding water is to increase mucus exudation in the gills, which results in reduced respiration function. Exposure to acidity and metals harms the reproduction cycle of fish by delaying the development of follicles into mature eggs and by hindering eggs' fertilisation and embryo development. On the biota level, the manifestation of ASS impact is often the absence of the species or species groups most vulnerable to acidity. The species of river fish that are vulnerable to acidity include, for example

Sulphate partitioning into calcite: Experimental verification of pH control and application to seasonality in speleothems

Science.gov (United States)

Wynn, Peter M.; Fairchild, Ian J.; Borsato, Andrea; Spötl, Christoph; Hartland, Adam; Baker, Andy; Frisia, Silvia; Baldini, James U. L.

2018-04-01

Carbonate-associated sulphate (CAS) is a useful carrier of palaeoenvironmental information throughout the geologic record, particularly through its stable isotope composition. However, a paucity of experimental data restricts quantitative understanding of sulphate incorporation into carbonates, and consequently CAS concentrations and their diagenetic modifications are rarely interpreted. However, in the case of calcite speleothems, the remarkably high-resolution CAS records which are obtainable via modern microanalytical techniques represent a potentially invaluable source of palaeoenvironmental information. Here, we describe the results of controlled experiments of sulphate co-precipitation with calcite in freshwater solutions where pH, saturation state, and sulphate concentration were varied independently of each other. Solution pH is confirmed as the principal control on sulphate incorporation into calcite. The relative efficiency of incorporation was calculated as a partition coefficient DSO4 = (mSO4/mCO3)solid/(mSO4/mCO3)solution. High crystal growth rates (driven by either pH or saturation state) encouraged higher values of DSO4 because of an increasing concentration of defect sites on crystal surfaces. At low growth rates, DSO4 was reduced due to an inferred competition between sulphate and bicarbonate at the calcite surface. These experimental results are applied to understand the incorporation of sulphate into speleothem calcite. The experimentally determined pH-dependence suggests that strong seasonal variations in cave air PCO2 could account for annual cycles in sulphate concentration observed in stalagmites. Our new experimentally determined values of DSO4 were compared with DSO4 values calculated from speleothem-drip water monitoring from two caves within the Austrian and Italian Alps. At Obir cave, Austria, DSO4 (×105) varies between 11.1 (winter) and 9.0 (summer) and the corresponding figures for Ernesto cave, Italy, are 15.4 (winter) and 14

Micrometeorological measurement of the dry deposition flux of sulphate and nitrate aerosols to coniferous forest

NARCIS (Netherlands)

Wyers, G.P.; Duyzer, J.H.

1997-01-01

Dry deposition fluxes of sulphate and nitrate have been determined over a coniferous canopy using the aerodynamic gradient technique. Vertical concentration gradients of sulphate and nitrate were measured with filters; the gradient of ammonium bisulphate was measured with thermodenuders. Filter

Aluminium Foam and Magnesium Compound Casting Produced by High-Pressure Die Casting

Directory of Open Access Journals (Sweden)

Iban Vicario

2016-01-01

Full Text Available Nowadays, fuel consumption and carbon dioxide emissions are two of the main focal points in vehicle design, promoting the reduction in the weight of vehicles by using lighter materials. The aim of the work is to evaluate the influence of different aluminium foams and injection parameters in order to obtain compound castings with a compromise between the obtained properties and weight by high-pressure die cast (HPDC using aluminium foams as cores into a magnesium cast part. To evaluate the influence of the different aluminium foams and injection parameters on the final casting products quality, the type and density of the aluminium foam, metal temperature, plunger speed, and multiplication pressure have been varied within a range of suitable values. The obtained compound HPDC castings have been studied by performing visual and RX inspections, obtaining sound composite castings with aluminium foam cores. The presence of an external continuous layer on the foam surface and the correct placement of the foam to support injection conditions permit obtaining good quality parts. A HPDC processed magnesium-aluminium foam composite has been developed for a bicycle application obtaining a suitable combination of mechanical properties and, especially, a reduced weight in the demonstration part.

Adsorption of lithium ion to amorphous hydrous aluminium oxide

International Nuclear Information System (INIS)

Wada, Hideo; Kitamura, Takao; Fujii, Ayako; Katoh, Shunsaku

1982-01-01

Adsorption process of lithium ion to amorphous hydrous aluminium oxide (a-HAO) was investigated by pH titration method with lithium chloride-lithium hydroxide mixed solution and X-ray diffraction analysis of a-HAO after pH titration. In the pH titration, the addition of hydroxide ion in amount from 0 to 4.0 mmol.g -1 gave no change to the pH of the solution and caused adsorption of lithium ion equivalent in amount to added hydroxide ion. X-ray diffraction analysis showed the formation of lithium hydrogenaluminate LiH (AlO 2 ) 2 .5H 2 O (LHA) in the a-HAO after pH titration. These results showed that adsorption of lithium ion by a-HAO was related to a reaction which consumed hydroxide ion and formed LHA. In order to elucidate detail process of the reaction, changes of pH, aluminium concentration and lithium concentration of the solution, respectively with time, were determined. The pH of the solution decreased in two stages. At the first stage of the pH decrease, the aluminium concentration increased whereas the lithium concentration did not change. At the second stage, the lithium concentration decreased together with the decrease of the aluminium concentration. It was inferred that adsorption of lithium ion proceeded through dissolution of a-HAO and precipitation of LHA. Theoretical adsorption capacity calculated from the above formula for LHA and aluminium content in a-HAO was 4.7 mmol.g -1 and agreed fairly well with observed value 4.0 mmol.g -1 . (author)

The soil sulphate effect and maize plant (Zea mays L.) growth of sulphate reducing bacteria (SRB) inoculation in acid sulfate soils with the different soil water condition

Science.gov (United States)

Asmarlaili, S.; Rauf, A.; Hanafiah, D. S.; Sudarno, Y.; Abdi, P.

2018-02-01

The objective of the study was to determine the potential application of sulphate reducing bacteria on acid sulfate soil with different water content in the green house. The research was carried out in the Laboratory and Green House, Faculty of Agriculture, Universitas Sumatera Utara. This research used Randomized Block Design with two treatments factors, ie sulphate reducing bacteria (SRB) isolate (control, LK4, LK6, TSM4, TSM3, AP4, AP3, LK4 + TSM3, LK4 + AP4, LK4 + AP3, LK6 + TSM3, LK6 + AP4, LK6 + AP3, TSM4 + TSM3, TSM4 + AP4, TSM4 + AP3) and water condition (100% field capacity and 110% field capacity). The results showed that application of isolate LK4 + AP4 with water condition 110% field capacity decreased the soil sulphate content (27.38 ppm) significantly after 6 weeks. Application of isolate LK4 + AP3 with water condition 110% field capacity increased soil pH (5.58) after-week efficacy 6. Application of isolate LK4 with water condition 110% field capacity increased plant growth (140 cm; 25.74 g) significantly after week 6. The best treatment was application isolate LK4 with water condition 110% field Capacity (SRB population 2.5x108; soil sulphate content 29.10ppm; soil acidity 4.78; plant height 140cm; plant weight 25.74g).

Coprecipitation of aluminium with hydroxides of tetra-, penta- and hexavalent actinides

International Nuclear Information System (INIS)

Yusov, A.B.; Budantseva, N.A.; Anan'ev, A.V.; Fedoseev, A.M.

2000-01-01

By the methods of IR spectroscopy and powder x-ray diffractometry precipitates formed in alkaline medium by actinide (4, 5, 6) in the presence of aluminium are studied. It is shown that in studied conditions formation of actinide aluminates not occurs. In the same time in the process of precipitation interaction of aluminium hydroxocomplexes with U(6) and Th(4) ions probably takes place. Hypothesis is expressed that possibility of aluminium hydroxocomplexes interaction with actinides in different oxidation state is depended on peculiarities of hydrolytic behaviour of the lasts [ru

Effect of temperature on sulphate reduction, growth rate and growth yield in five psychrophilic sulphate-reducing bacteria from Arctic sediments

DEFF Research Database (Denmark)

Knoblauch, C.; Jørgensen, BB

1999-01-01

and T(opt). For strains LSv21 and LSv514, however, growth yields were highest at the lowest temperatures, around 0 degrees C. The results indicate that psychrophilic sulphate-reducing bacteria are specially adapted to permanently low temperatures by high relative growth rates and high growth yields......Five psychrophilic sulphate-reducing bacteria (strains ASv26, LSv21, PSv29, LSv54 and LSv514) isolated from Arctic sediments were examined for their adaptation to permanently low temperatures, All strains grew at -1.8 degrees C, the freezing point of sea water, but their optimum temperature...... for growth (T(opt)) were 7 degrees C (PSv29), 10 degrees C (ASv26, LSv54) and 18 degrees C (LSv21, LSv514), Although T(opt) was considerably above the in situ temperatures of their habitats (-1.7 degrees C and 2.6 degrees C), relative growth rates were still high at 0 degrees C, accounting for 25...

Removal of Pb (II from Aqueous Solutions Using Mixtures of Bamboo Biochar and Calcium Sulphate, and Hydroxyapatite and Calcium Sulphate

Directory of Open Access Journals (Sweden)

Ahmed Hassan

2016-01-01

Full Text Available Sorption characteristics of Pb(II from aqueous solutions through a low-cost adsorbent mixture comprising of Bamboo biochar (BB and Calcium Sulphate (CS, and a more expensive mixture of Hydroxyapatite (HAP and Calcium Sulphate (CS, were investigated. The effects of equilibrium contact time, and adsorbate concentration conducted in batch experiments were studied. Adsorption equilibrium was established in 40 (min. The adsorption mechanism of Pb(II from these two adsorbent mixtures was carried out through a kinetic rate order. A pseudo second-order kinetic model was applied for the adsorption processes. The model yielded good correlation (R2 >0.999 of the experimental data. Adsorption of Pb(II using (BB&CS and (HAP&CS correlated well (R2 >0.99 with both the Langmuir and Freundlich isotherm equations under the concentration range studied. Hence, the effectiveness of an inexpensive natural material (BB&CS mixture in Pb(II removal is established, and is promising for use in other heavy metal adsorptions.

A study on the role of diboride in the heterogeneous nucleation of aluminium

International Nuclear Information System (INIS)

Suarez, O. M.

2004-01-01

The intangible role of titanium and aluminium diboride in the nucleation of aluminium was re-examined. Two different techniques, complemented with scanning electron microscopy, allowed determining the stability of the diboride in the presence of titanium tri aluminides and liquid aluminium phases. Through rapid scintillated quenching the high temperature diboride were retained and studied. Then, in a diffusion couple, the reactivity of such diboride was tested in contact with pure titanium tri aluminide. It is proposed that a ternary diboride acts as the main catalytic particle in the crystallization of aluminium alloys with refined grains. (Author) 27 refs

Mechanism of protection of adenosine from sulphate radical anion ...

Indian Academy of Sciences (India)

Unknown

Keywords. Repair by caffeic acid; repair of adenosine radicals; oxidation by sulphate radical anions. ... known that hydroxycinnamic acids are natural anti- oxidants ... acid. 2. Experimental ..... ously and independently under kinetic conditions at.

Study of the electronic structure of pure aluminium, aluminium oxide and nitride by spectroscopy of electrons excited under electronic and photonic bombardment (X and UV)

International Nuclear Information System (INIS)

Gautier-Soyer, Martine

1985-01-01

This research thesis reports the use of electron spectroscopy with electrons excited under electronic or photonic (X or UV) bombardment for the study of electronic state density of aluminium, aluminium oxide (Al 2 O 3 ) and aluminium nitride (AlN). The objective is to get an insight into phenomena related to technological problems of adherence, wear, lubrication, corrosion or breakdown met in metals, insulators and semiconductors. The author highlighted the presence of occupied surface states on Al(111) and Al(100), and electronic levels localised in the forbidden band of Al 2 O 3 and AlN, induced by structural defects which promote surface reactivity [fr

Effect of aluminium particles on mechanical and morphological properties of epoxy nanocomposites

Directory of Open Access Journals (Sweden)

Bello Sefiu A.

2017-01-01

Full Text Available Bumper is a front or rear part of automobiles. It is designed and shaped to be impact absorbing and protecting automobiles from damage in low impact collisions. Initially, they were made from heavy steels, increasing the weight of automobiles and fuel consumption. Also, high impacts of steel bumpers on pedestrians during accidental collision cause fatalities and or disabilities. An effort to enhance fuel efficiency, safety, freedom of design and shape detailing, heavy alloys for automobile applications are now being replaced with polymeric composites. Aluminium micro particles and nanoparticles were prepared from aluminium cans through sand casting, lathe machine spinning, and ball milling techniques. Both types of aluminium particles were incorporated into a mixture of diglycidyl ether of bisphenol A (DGEBA, epoxy resin cured with amine base hardener (ABH. Phases of the epoxy polymer and composites were identified using Xray Diffraction (XRD. Spatial arrangement of the phases within the matrix and their elemental composition were examined using Scanning Electron Microscope with attached energy dispersive X-ray spectroscopy (SEM/EDX. Tensile, impact and micro hardness tests were conducted on the prepared epoxy/aluminium composites. Results of the XRD showed the presence of aluminium compounds/phases due to chemical reactions between aluminium particles and DGEBA/ABH system. SEM confirmed a homogeneous distribution of the phases within the epoxy matrix, and that there is a strong adhesion between the epoxy matrix and aluminium particles. Correlation between the mechanical properties of the prepared nanocomposite and the procured bumper materials exhibited a fair suitability of the prepared nanocomposites for automobile applications.

Susceptibility of salmonid fish to poisons under estuarine conditions. I. Zinc sulphate

Energy Technology Data Exchange (ETDEWEB)

Herbert, D W.M.; Wakeford, A C

1964-01-01

The resistance of yearling rainbow trout and Atlantic salmon smolts to zinc sulphate increases with salinity up to 30-40 percent sea water, in which these species can withstand for 2 days respectively 15 and 13 times as much zinc sulphate as on fresh water. Further increase in salinity to 72 percent sea water reduces tolerance for the zinc salt. Salmon smolts were more susceptible to zinc poisoning than trout in fresh water and at all salinities tested.

Comparative performance of aluminium copper and iron solar stills

International Nuclear Information System (INIS)

Dioha, I.J.; Nwagbo, E.E.; Gulma, N.A.

1990-12-01

Three different metal sheets have been used in the fabrication of three different single sloping solar stills of the same surface geometry. The metals were galvanized iron, aluminium and copper. This paper presents the performance of the different stills operating under the same environmental conditions. The observed distillate yields was greatest for copper, then aluminium and lastly, iron still. The differences in the yields is attributed to the differences in the thermal conductivities of the metals. The equivalent local costs for the fabrication of the copper, aluminium and iron stills are respectively $160, $95 and $60. Taking the long run costs into consideration, the copper still is preferred because of its availability, durability, weldability and relatively higher conductivity of 380Wm -1 K -1 value. (author). 9 refs, 2 figs, 2 tabs

Aluminium and Alzheimer's disease: the science that describes the link

National Research Council Canada - National Science Library

Exley, Christopher

2001-01-01

... that has been encircled is the gene for the amyloid precursor protein. (Thanks to Walter Lukiw for supplying this information.) Aluminium and Alzheimer's Disease: The Science that Describes the LinkAluminium and Alzheimer's Disease The Science that Describes the Link Edited by Christopher Exley Birchall Centre for Inorganic Chemistry and Materials Scienc...

Activation Analysis of Aluminium

Energy Technology Data Exchange (ETDEWEB)

Brune, Dag

1961-01-15

An analysis of pure aluminium alloyed with magnesium was per- formed by means of gamma spectrometry , Chemical separations were not employed. The isotopes to be determined were obtained in conditions of optimum activity by suitably choosing the time of irradiation and decay. The following elements were detected and measured quantitatively: Iron, zinc, copper, gallium, manganese, chromium, scandium and hafnium.

Decolourisation and degradation of textile dyes using a sulphate ...

African Journals Online (AJOL)

SERVER

2008-01-18

Jan 18, 2008 ... Full Length Research Paper ... and microflora that augmented a sulphate reducing bacteria (SRB) consortium. ... and degradation of aromatic compounds from the deco- ... ed that aromatic amines are toxic, carcinogenic and.

Diagnostics of ytterbium/aluminium laser plasmas

International Nuclear Information System (INIS)

Bailey, J.; Lee, R.W.; Landen, O.L.; Kilkenny, J.D.; Lewis, C.L.; Busquet, M.

1986-11-01

Microdot spectroscopy was used to study the x-ray emission from laser-produced plasmas consisting of 10% ytterbium, 90% aluminium. Spectra were recorded with a space-resolving flat crystal (PET) mini-spectrometer in the 4.0-8.0 A range. The Janus research laser at LLNL irradiated the targets with green (0.53 μm) light in a 1 nsec pulse. The power density was varied between 4x10 13 and 3x10 14 W/cm 2 . The plasma electron density and temperature were determined from the aluminium XI, XII and XIII line emission. By examining correlations between changes in the plasma conditions with changes in the ytterbium spectra, we will determine the potential for using ytterbium line emission as a plasma diagnostic

Prevention of Bed Agglomeration Problems in a Fluidized Bed Boiler by Finding the Trigging Value of Sewage Sludge Dosage Added to Combustion of Biofuels

Energy Technology Data Exchange (ETDEWEB)

Andersson, Kajsa; Gervind, Pernilla

2009-07-01

Agglomeration of bed sand is a common problem during combustion of biofuels with high ash content in fluidized bed boilers. Former studies have shown that co-combustion of biofuels with sewage sludge increases the agglomeration temperature. Sewage sludge has a low heating value and high ash content. It would therefore be better to use sludge as an additive to the combustion than as a co-combusted biofuel. In this study the trigging value of sludge addition to the combustion of some biofuel was investigated. The effect of adding sludge with different precipitation chemicals, iron sulphate and aluminium sulphate, was investigated. The biofuels used for the experiments were bark, refused derived fuel (RDF) and a mixture of wood and straw, 75/25 % on energy basis. All experiments were carried out in a laboratory scale fluidized bed reactor. Analyses of chemical composition of bed sand and SEM/EDX analyses were performed after the combustion. Eventually agglomeration tests were performed in order to find the agglomeration temperature of the samples. Some of the samples sintered during the combustion and were not tested for the agglomeration temperature. SEM/EDX showed that all samples of bed sand contained sand particles with more or less coatings. In some cases the coatings seemed to consist of one dense inner layer and one more porous outer layer. From SEM/EDX and chemical composition analyses it was found that the total amount of phosphorous in the bed sand samples was increased with an increased addition of sludge in all experiments. The concentration of phosphorous was especially higher in the outer layers/coatings. It was also found that elements from the sludge seem to get caught by a sticky layer at the bed sand surface and form a non-sticky or less sticky layer that prevents agglomeration. The total amount of aluminium was increased with an increased addition of sludge for the wood/straw samples, while it increased with an increased amount of combusted fuel for

Corrosion of research reactor aluminium clad spent fuel in water

International Nuclear Information System (INIS)

2009-12-01

A large variety of research reactor spent fuel with different fuel meats, different geometries and different enrichments in 235 U are presently stored underwater in basins located around the world. More than 90% of these fuels are clad in aluminium or aluminium based alloys that are notoriously susceptible to corrosion in water of less than optimum quality. Some fuel is stored in the reactor pools themselves, some in auxiliary pools (or basins) close to the reactor and some stored at away-from-reactor pools. Since the early 1990s, when corrosion induced degradation of the fuel cladding was observed in many of the pools, corrosion of research reactor aluminium clad spent nuclear fuel stored in light water filled basins has become a major concern, and programmes were implemented at the sites to improve fuel storage conditions. The IAEA has since then established a number of programmatic activities to address corrosion of research reactor aluminium clad spent nuclear fuel in water. Of special relevance was the Coordinated Research Project (CRP) on Corrosion of Research Reactor Aluminium Clad Spent Fuel in Water (Phase I) initiated in 1996, whose results were published in IAEA Technical Reports Series No. 418. At the end of this CRP it was considered necessary that a continuation of the CRP should concentrate on fuel storage basins that had demonstrated significant corrosion problems and would therefore provide additional insight into the fundamentals of localized corrosion of aluminium. As a consequence, the IAEA started a new CRP entitled Corrosion of Research Reactor Aluminium Clad Spent Fuel in Water (Phase II), to carry out more comprehensive research in some specific areas of corrosion of aluminium clad spent nuclear fuel in water. In addition to this CRP, one of the activities under IAEA's Technical Cooperation Regional Project for Latin America Management of Spent Fuel from Research Reactors (2001-2006) was corrosion monitoring and surveillance of research

Growth morphology of zinc tris(thiourea) sulphate crystals

Indian Academy of Sciences (India)

The growth morphology of crystals of zinc tris(thiourea) sulphate (ZTS) is investigated experimentally, and computed using the Hartman–Perdok approach. Attachment energies of the observed habit faces are calculated for determining their relative morphological importance. A computer code is developed for carrying out ...

A note on the behind armour effects from perforated alumina/aluminium targets

OpenAIRE

Hazell, P. J.; Fellows, N. A.; Hetherington, J. G.

1998-01-01

A thin, ceramic-faced armour, separated from a thick metal block, has been subjected to high-velocity impact by a 6.35 mm diameter steel sphere. Experimental work was carried out which compared firings into ceramic-faced aluminium armour, separated from thick aluminium witness blocks, with firings into the thick aluminium blocks alone. The depth of penetration and the area of damage were measured and an estimated percentage weight saving due to the inclusion of the ceramic-f...

Corrosion behaviour of nanometre sized cerium oxide and titanium oxide incorporated aluminium in NaCl solution

International Nuclear Information System (INIS)

Ashraf, P. Muhamed; Edwin, Leela

2013-01-01

Highlights: ► Corrosion resistant aluminium incorporated with nano oxides of cerium and titanium. ► 0.2% nano CeO 2 and 0.05% nano TiO 2 showed increased corrosion resistance. ► Nano TiO 2 concentration influenced the optimum performance of the material. ► Comparison of Micro and nano CeO 2 and TiO 2 aluminium showed the latter is best. - Abstract: The study highlights the development of an aluminium matrix composite by incorporating mixture of nanometre sized cerium oxide and titanium oxide in pure aluminium and its corrosion resistance in marine environment. The mixed nanometre sized oxides incorporated aluminium exhibited improved microstructure and excellent corrosion resistance. Corrosion resistance depends on the concentration of nanometre sized titanium oxide. Electrochemical characteristics improved several folds in nanometre sized mixed oxides incorporated aluminium than micrometre sized oxides incorporated aluminium.

Purity and surface roughness of vacuum deposited aluminium films

Energy Technology Data Exchange (ETDEWEB)

Dhere, N G; Arsenio, T P [Instituto Militar de Engenharia, Rio de Janeiro (Brazil); Patnaik, B K [Pontificia Universidade Catolica do Rio de Janeiro (Brazil). Instituto de Fisica; Assuncao, F C.R.; de Souza, A M [Pontificia Universidade Catolica do Rio de Janeiro (Brazil). Departamento de Ciencia dos Materiais e Metalurgia

1975-04-01

The authors studied the purity, surface roughness and grain size of vacuum-deposited aluminium films, using an intermetallic crucible and a continuous feed of pure aluminium wire. The grain size and roughness were studied by electron difraction, X-ray diffraction and the scanning electron microscope. Purity was determined by X-ray fluorescence produced by proton bombardment in the Van de Graaff accelerator and by X-ray and optical emission spectrometry.

Anodically generated manganese(III) sulphate for the oxidation of ...

Indian Academy of Sciences (India)

Unknown

oxidation of dipeptides in aqueous sulphuric acid medium: A kinetic study ... acetic acid (TFA) and N-methylmorpholine (NMM) were purchased ... and chloroform–methanol– acetic acid .... tion), manganese(II) sulphate and water (to keep the.

On the anodic aluminium oxide refractive index of nanoporous templates

International Nuclear Information System (INIS)

Hierro-Rodriguez, A; Rocha-Rodrigues, P; Araujo, J P; Valdés-Bango, F; Alameda, J M; Teixeira, J M; Jorge, P A S; Santos, J L; Guerreiro, A

2015-01-01

In the present study, we have determined the intrinsic refractive index of anodic aluminium oxide, which is originated by the formation of nanoporous alumina templates. Different templates have been fabricated by the conventional two-step anodization procedure in oxalic acid. Their porosities were modified by chemical wet etching allowing the tuning of their effective refractive indexes (air-filled nanopores  +  anodic aluminium oxide). By standard spectroscopic light transmission measurements, the effective refractive index for each different template was extracted in the VIS–NIR region. The determination of the intrinsic anodic aluminium oxide refractive index was performed by using the Maxwell–Garnett homogenization theory. The results are coincident for all the fabricated samples. The obtained refractive index (∼1.55) is quite lower (∼22%) than the commonly used Al 2 O 3 handbook value (∼1.75), showing that the amorphous nature of the anodic oxide structure strongly conditions its optical properties. This difference is critical for the correct design and modeling of optical plasmonic metamaterials based on anodic aluminium oxide nanoporous templates. (paper)

ADC3 YANG DIBUAT DENGAN PELEBURAN ULANG ALUMINIUM BEKAS SEBAGAI BAHAN PROPELER KAPAL KAYU

Directory of Open Access Journals (Sweden)

Suyanto Suyanto

2016-11-01

Full Text Available Saat ini pembuatan propeler aluminium pada industri kecil banyak memanfaatkan bahan dasar aluminium bekas. Namun produk yang dihasilkan belum memenuhi spesifikasi standar material. Penelitian dilakukan dengan menggunakan bahan dasar aluminium siku bekas dan aluminium kampas bekas. Variasi penambahan TiB sebagai grain refiner dilakukan pada saat peleburan. Perhitungan dengan simulasi Excel dilakukan untuk memperkirakan komposisi hasil pengecoran yang sesuai. Pengecoran ulang menghasilkan produk dengan tingkat porositas 3,3 % sampai 5,9 %. Penggunaan cetakan pasir ikut berperan dalam timbulnya porositas. Penambahan TiB sebanyak 0,5% ke ADC3 berpengaruh pada penurunan ukuran butir hingga 50%, peningkatan kekerasan hingga 23%, peningkatan kekuatan tarik hingga 11%, serta penurunan keuletan hingga 20%. Kata kunci: ADC3, pengecoran ulang aluminium, propeler.

A reliability based stress-life evaluation of aluminium-graphite particulate composites

International Nuclear Information System (INIS)

Achutha, M.V.; Sridhara, B.K.; Abdul Budan, D.

2008-01-01

Fatigue tests were conducted on sand cast aluminium-graphite composite specimens on Rotating Beam Fatigue Testing Machine with three different stress levels. Aluminium-graphite (LM 25-5% graphite) composite was processed by closed mould sand casting method. Three-stress level fatigue test program was planned for carrying out fatigue experiments. Three different stress levels selected for fatigue experiments were a fraction of ultimate tensile strength. Statistical design of fatigue experiments was carried out to determine the sample size at each stress level. Experimental results are presented in the form of stress-life (S-N) curves and reliability-stress-life (R-S-N) curves, which are helpful for designers. The S-N curve of the aluminium-graphite composite was compared with its matrix alloy LM 25. Comparison revealed that the fatigue behaviour of the aluminium-graphite composite is superior to that of the matrix alloy

A kinetic approach of sulphur behaviour in borosilicate glasses and melts: implications for sulphate incorporation in nuclear waste glasses

Energy Technology Data Exchange (ETDEWEB)

Lenoir, Marion [Service de Confinement des Dechets et Vitrification - Laboratoire d' Etudes de Base sur les Verres, CEA Valrho, Centre de Marcoule, 30207 Bagnols sur Ceze (France); Physique des Mineraux et des Magmas, UMR 7047 - CNRS, Institut de Physique du Globe de Paris, 7 place Jussieu, 75252 Paris Cedex 05 (France); Grandjean, Agnes [Service de Confinement des Dechets et Vitrification - Laboratoire d' Etudes de Base sur les Verres, CEA Valrho, Centre de Marcoule, 30207 Bagnols sur Ceze (France); Neuville, Daniel R. [Physique des Mineraux et des Magmas, UMR 7047 - CNRS, Institut de Physique du Globe de Paris, 7 place Jussieu, 75252 Paris Cedex 05 (France)

2008-07-01

The kinetics of sulphate decomposition in a borosilicate melt were studied using in situ Raman spectroscopy. This technique permits the quantification of the amount of sulphate dissolved in a borosilicate glass as a function of heating time by comparison with measurements obtained by microprobe WDS (Wavelength Dispersive Spectrometry). In order to quantify the content of sulphate obtained by Raman spectroscopy, the integrated intensity of the sulphate band at 985 cm{sup -1} was scaled to the sum of the integrated bands between 800 and 1200 cm{sup -1}, bands that are assigned to Q{sup n} silica units on the basis of previous literature. Viscosities of some borosilicate glasses are also presented here in order to study the kinetics of sulphate decomposition as a function of the viscosity of the melt. This underlines the importance of variations in viscosity depending on the composition of the melt and thus shows that viscosity is an important parameter governing the kinetics of decomposition of sulphate in borosilicate glasses. (authors)

TiO2 effect on break-down of low-grade tantalum-niobium concentrates in the process of sulphatization

International Nuclear Information System (INIS)

Petrova, N.V.; Popov, A.D.; Mulenko, V.N.

1982-01-01

The effect of TiO 2 additive or materials containing it on tantalum-niobate decomposition in the process of sulphatization is investigated. It is shown that favourable effect of titanium dioxide in the process of sulphatization is especially noticeable in reprocessing of hard-brokening down tantalum-niobium concentrates with low Nb:Ta ratio etc. Chemical composition and type of tantalum-niobium mineralization of enrichment products used in the given investigation is presented. It is stated that the degree of concentrate break-down under similar sulphatization conditions (t=230 deg C; tau=2 h) essentially depends on the quantity of the introduced titanium dioxide. It is shown that sulphatization in the presence of titanium dioxide additive or materials containing it permits to exercise practically complete break-down of lean tantalum-niobium raw material, to avoid application of complexers in leaching of sulphatization products

Corrosion behaviour of zinc and aluminium in simulated nuclear accident environments

International Nuclear Information System (INIS)

Piippo, J.; Laitinen, T.; Sirkiae, P.

1997-02-01

The corrosion rates of zinc and aluminium were determined in simulated large pipe break and in severe accident cases. An in situ on fine measurement technique, which is based on the resistance measurement of sample wires, was used. In the large pipe break case the corrosion rates of zinc and aluminium were determined at pH 8 and pH 10 in deaerated and in aerated solutions. Tests were also performed in aerated 0.1 M borate buffer solution at pH 9.2. Temperature range was 130 deg C - 50 deg C. The corrosion of zinc appears to be relatively fast in neutral or mildly alkaline aerated water, while both high pH and deaeration tend to reduce the corrosion rates of zinc. The aeration and pH elevation decrease the corrosion rate of aluminium. The simulation of the severe accident case took place in the pH range 3-11 in chloride containing solutions at 50 deg C temperature. The corrosion rate of aluminium was lower than that of zinc, except for the solution with pH 11, in which the corrosion rate of aluminium was practically identical to that of zinc. Both metals corroded more rapidly in the presence of chlorides in acidic and alkalic conditions than in the absence of chlorides at neutral environment. The solubility of zinc and aluminium and the stability of the corrosion products were estimated using thermodynamical calculations. The experimental results and the thermodynamical calculations were in fair agreement. (8 refs.)

Pengaruh Kuat Arus Listrik Dan Waktu Proses Anodizing Dekoratif Pada Aluminium Terhadap Kecerahan Dan Ketebalan Lapisan

Directory of Open Access Journals (Sweden)

I Gst. Ngr. Nitya Santhiarsa

2012-11-01

Full Text Available To increase assess aluminium of decorative aspect hence finishing processes must be used, like coloringprocess. Hence layer anodizing developed now where you can make aluminum metal look more interesting so thefinish can increase the economic value. Anodizing is the process formation of oxide layer on the metal with themetal, especially aluminum reacting with oxygen (O2 from the electrolyte sulphate acid (H2SO4.This research uses2024-T3 aluminum metal as a parent to be coated, with the electric current treatment 1 Ampere, 2 Ampere, Ampere,and 3, and changes in immersion variations time 10 minutes, 20 minutes, and 30 minutes. Tests performed includetesting the brightness (light illumination and layer thickness measurement.The result of research show that bestvalue for the examination of brightness obtained at electrics current 1 ampere and time anodizing 10 minute equal to11519.53 lumens/m2 and thickness obtained at electrics current 3 ampere and anodizing time 30 minute equal to 5?m, value lowest for the examination of brightness obtained at electrics current 1 ampere and time anodizing 10minute equal to 10180.05 lumens/m2 and thickness obtained at electrics current 3 ampere and anodizing time 30minute equal to 2?m

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

Energy Technology Data Exchange (ETDEWEB)

Hoenicke, D.; Moeller, T.; Schwarz, T.

1998-01-31

A new electrolytic process was developed to form solar selective layers on aluminium. In the developed process, both the formation of the alumina layer and the deposition of metals into the layer takes place in only one treatment step using a single electrolysis bath. The main step of the so called ISOC-method (impulse structured oxide ceramic) is the anodic oxidation of aluminium which was carried out by using a pulse technique at different voltages. During the anodic polarisation a thin alumina ceramic layer was formed, while the cathodic led to the metal deposition as copper and nickel. The conditions of the electrolysis were varied in order to estimate optimal parameters achieving solar selective layers with high selectivity. Furthermore, a scale-up of the lab scale apparatus to a mini plant was carried out. Finally, the corrosion resistance of the absorber layers was improved by the formation of a thin hydrophobic overlayer using a sol-gel treatment. (orig.) [Deutsch] Ein neuartiges Behandlungsverfahren zur Erzeugung von solarselektiven Absorberschichten auf Aluminium wurde entwickelt. Bei dieser elektrochemischen Behandlung wird in einem Einstufenprozess mit einem Elektrolyten durch eine Kombination von anodischer Oxidation und bipolarer Pulsbehandlung auf der Oberflaeche des Aluminiums eine impulsstrukturierte Oxidkeramik (ISOK) erzeugt. Dabei entsteht durch eine anodische Oxidation eine strukturierte Aluminiumoxidschicht. Bei der bipolaren Pulsbehandlung erfolgt dann eine Abscheidung der im ISOK-Elektrolyten befindlichen Metalle Cu und Ni auf oder in die Aluminiumoxidoberflaeche. Die ISOK-Behandlung wurde vom Labormassstab zu einem ISOK-Verfahren im Miniplant-Massstab entwickelt. Der Einfluss der elektrischen Parameter und der chemischen Zusammensetzung der ISOK-Elektrolyte wurde untersucht. Durch eine auf das ISOK-Verfahren abgestimmte Nachbehandlung, ein Tauchverfahren in einer Sol-Gel-Loesung, entsteht ein Schichtsystem mit hoher Solarselektivitaet

The microbial communities and potential greenhouse gas production in boreal acid sulphate, non-acid sulphate, and reedy sulphidic soils

Czech Academy of Sciences Publication Activity Database

Šimek, Miloslav; Virtanen, S.; Simojoki, A.; Chroňáková, Alica; Elhottová, Dana; Krištůfek, Václav; Yli-Halla, M.

2014-01-01

Roč. 466, January (2014), s. 663-672 ISSN 0048-9697 R&D Projects: GA ČR GA526/09/1570; GA MŠk LC06066 Grant - others:GAJU(CZ) GAJU 138/2010/P Institutional support: RVO:60077344 Keywords : acid sulphate soil * carbon * CARD-FISH * microorganisms * nitrogen * PLFA Subject RIV: EE - Microbiology, Virology Impact factor: 4.099, year: 2014

Friction conditions in the bearing area of an aluminium extrusion process

NARCIS (Netherlands)

Ma, X.; de Rooij, Matthias B.; Schipper, Dirk J.

2012-01-01

In aluminium extrusion processes, friction inside the bearing channel is important for controlling the surface quality of the extrusion products. The contact materials show a large hardness difference, one being hot aluminium, and the other being hardened tool steel. Further, the contact pressure is

Anisotropy in elastic properties of lithium sodium sulphate ...

Indian Academy of Sciences (India)

Anisotropy in elastic properties of lithium sodium sulphate hexahydrate single crystal—An ultrasonic study. GEORGE VARUGHESE. ,∗. , A S KUMAR†, J PHILIP†† and GODFREY LOUIS#. Department of Physics, Catholicate College, Pathanamthitta 689 648, India. †SPAP, M.G. University, Kottayam 686 560, India. ††STIC ...

calcium sulphate hemihydrate and bioactive glass composites for ...

Indian Academy of Sciences (India)

Home; Journals; Bulletin of Materials Science; Volume 41; Issue 2. In vitro bioactivity evaluation of α -calcium sulphate hemihydrate and bioactive glass composites for their potential use in bone regeneration. YANYAN ZHENG CHENGDONG XIONG DUJUAN ZHANG LIFANG ZHANG. Volume 41 Issue 2 April 2018 Article ID ...

Conductance and bulk vertical detachment energy of hydrated sulphate and oxalate dianions: a theoretical study

Science.gov (United States)

Pathak, Arup Kumar

2014-06-01

Analytical expressions have been derived for the vertical detachment energy (VDE) for hydrated sulphate (SO2 -4) and oxalate (C2O2 -4) dianions that can be used to calculate the same over a wide range of cluster sizes including the bulk from the knowledge of VDE for a finite number of stable clusters. The calculated bulk detachment energies are found to be very good in agreement (within 5%) with the available experimental results for both the systems. It is observed that two or more water molecules will be essential for the stability of sulphate and oxalate dianions against spontaneous electron loss and this is consistent with the experiment. We have, for the first time, provided a scheme to calculate the radius of the solvent berg for sulphate and oxalate dianions. The calculated conductivity values for the sulphate and oxalate dianions using Stokes-Einstein relation and the radius of solvent berg are found to be very good in agreement (within 4%) with the available experimental results.

Propolis Protection from Toxicity Caused by Aluminium Chloride in Male Rats

International Nuclear Information System (INIS)

Mangood, S.A.; Kamal, A.M.; Haggag, A.M.

2012-01-01

Propolis is a resinous natural hive product derived from plant exudate collected by honey bees and has been extensively used in folk medicine. The present study was undertaken to determine the effectiveness of propolis in alleviating the toxicity of aluminium chloride (AlCl 3 )on some hematological and biochemical parameters of male albino rats. Twenty four male albino rats were arranged into 4 equal groups; control group, aluminium group (34 mg AlCl 3 /kg/day), propolis group (100μg propolis/rat)and aluminium plus propolis group. Rats were orally administered their respective doses daily for 30 days. AlCl 3 caused significant decrease in hemoglobin (Hb), red blood cell count (RBC), hematocrit (Ht), total and differential leucocyte count (TLC) when compared to control. On the other hand, aluminium administration caused a significant increase in urea, uric acid, creatinin, bilirubin, the content of phosphorous, alanine aminotransferase (ALT) and asparate aminotransferase (AST) and significant decrease in total protein, albumin, globulin and calcium when compared to control. The administration of propolis alleviated the toxic effect of AlCl 3 in experimental rats. It could be concluded thal propolis my afford protection from toxicity caused by aluminium chloride in male albino rats

Toxic effects of chromic sulphate on the common carp, Cyprinus carpio

Energy Technology Data Exchange (ETDEWEB)

Wong, M.H.; Lau, W.M.; Tong, T.Y.; Liu, W.K.; Luk, K.C.

1982-02-01

The effects of chromic sulphate, which is commonly used in the tanning of leather, on the common carp, Cyprinus carpio and the bighead, Aristichthys nobilis, were studied. C. carpio was found to be more susceptible than A. nobilis to chromic sulphate at the lowest concentration tested (100 mg/l) whereas results obtained at other concentration were similar for both species. Damage to the gills, liver and intestine was observed by histopathological examination. A wide range of chemicals is used in the different stages of treating leather and a possible treatment of the effluent from the tanneries is suggested.

Biological sulphate removal from acid mine effluent using ethanol as carbon and energy source

CSIR Research Space (South Africa)

Greben, HA

2000-01-01

Full Text Available nutrients (P and N) added to the feed were completely uti- lized. Iron and copper were removed completely and aluminium, manganese and zinc decreased to less than 4 mg/l. Aluminium precipitated as Al(OH)3 and the other metals as metal sulphides. Conclusions...

Performance of Periwinkle Shell Ash Blended Cement Concrete Exposed to Magnesium Sulphate

Directory of Open Access Journals (Sweden)

Umoh A.A.

2013-01-01

Full Text Available The study examined the compressive strength of periwinkle shell ash (PSA blended cement concrete in magnesium sulphate medium. Specimens were prepared from designed characteristics strength of 25 MPa. The cement replacement with PSA ranged between 0 and 40% by volume. A total of 180 cube specimens were cast and cured in water. At 28 days curing, 45 specimens each were transferred into magnesium sulphate of 1%, 3%, and 5% solution, while others were continuously cured in water and tested at 62, 92, and 152 days. The results revealed a higher loss in compressive strength with the control mix, and that it increases with increased in MgSO4 concentration and exposure period, whereas, the attack on the PSA blended cement concrete was less and the least value recorded by 10% PSA content. Therefore, the study concluded that the optimum percentage replacement of cement with 10% PSA could mitigate magnesium sulphate attack.

Gasification of sulphate soap for the lime kiln

Energy Technology Data Exchange (ETDEWEB)

Saviharju, Kari (Valtion Teknillinen Tutkimuskeskus, Espoo (Finland). Lab. of Fuel and Process Technology); Timonen, Tuomas (Finnish Energy Economy Association, Espoo (Finland). Finnish Recovery Boiler Committee)

1993-01-01

Sulphate soap is a by-product of pulp mills utilized as a raw material for the chemical industry. However, this results in an increase in sulphur input of several kilograms SO[sub 2] per ADt pulp into the mill. Another increasingly interesting alternative is to utilize soap in the lime kiln of the mill. This has a positive effect, in addition to sulphur problems, on the energy balance of the mill. The crucial problem is the high Na + K content of soap, from 4 to 8%, which can result in plugging of the lime kiln. The operational problems can be avoided by gasifying the soap and by separating the inorganic materials from the product gas before the kiln. This paper describes research work on the gasification of crude sulphate soap carried out at the Technical Research Centre of Finland (VTT) over the years 1991 and 1992. This work will be continued in 1993 by focusing on specified problems, after which commercial applications should be available. (author)

Coastal acid sulphate soils in Poland: a review

Directory of Open Access Journals (Sweden)

Hulisz Piotr

2017-03-01

Full Text Available This paper presents the state of knowledge on coastal acid sulphate soils in Poland. The properties of these soils are closely related to the influence of brackish water from the Baltic Sea, high accumulation of organic matter and human activity. The obtained results demonstrate that the sulphide accumulation in soils refers to a relatively small areas of the Polish coastal zone with the unique and very valuable habitats. They require an adequate regulation of the water relations to avoid the risk of strong soil acidification and environmental pollution by heavy metals. Currently, there are no relevant criteria for classification of acid sulphate soil materials in the Polish Soil Classification (2011. Therefore, based on the presented data, the authors proposed to identify these features at the lower classification level (for different soil types. The criteria for the Thionic and Sulfidic qualifiers used in the WRB classification (IUSS Working Group WRB 2015 could be accepted for this purpose.

Uptake and metabolism of sulphated steroids by the blood-brain barrier in the adult male rat.

Science.gov (United States)

Qaiser, M Zeeshan; Dolman, Diana E M; Begley, David J; Abbott, N Joan; Cazacu-Davidescu, Mihaela; Corol, Delia I; Fry, Jonathan P

2017-09-01

Little is known about the origin of the neuroactive steroids dehydroepiandrosterone sulphate (DHEAS) and pregnenolone sulphate (PregS) in the brain or of their subsequent metabolism. Using rat brain perfusion in situ, we have found 3 H-PregS to enter more rapidly than 3 H-DHEAS and both to undergo extensive (> 50%) desulphation within 0.5 min of uptake. Enzyme activity for the steroid sulphatase catalysing this deconjugation was enriched in the capillary fraction of the blood-brain barrier and its mRNA expressed in cultures of rat brain endothelial cells and astrocytes. Although permeability measurements suggested a net efflux, addition of the efflux inhibitors GF120918 and/or MK571 to the perfusate reduced rather than enhanced the uptake of 3 H-DHEAS and 3 H-PregS; a further reduction was seen upon the addition of unlabelled steroid sulphate, suggesting a saturable uptake transporter. Analysis of brain fractions after 0.5 min perfusion with the 3 H-steroid sulphates showed no further metabolism of PregS beyond the liberation of free steroid pregnenolone. By contrast, DHEAS underwent 17-hydroxylation to form androstenediol in both the steroid sulphate and the free steroid fractions, with some additional formation of androstenedione in the latter. Our results indicate a gain of free steroid from circulating steroid sulphates as hormone precursors at the blood-brain barrier, with implications for ageing, neurogenesis, neuronal survival, learning and memory. © 2017 International Society for Neurochemistry.

High-purity aluminium creep under high hydrostatic pressure

International Nuclear Information System (INIS)

Zajtsev, V.I.; Lyafer, E.I.; Tokij, V.V.

1977-01-01

The effect of the hydrostatic pressure on the rate of steady-state creep of high-purity aluminium was investigated. It is shown that the hydrostatic pressure inhibits the creep. The activation volume of the creep is independent of the direction in the range of (4.7-6.2) kg/mm 2 and of the pressure in the range of (1-7.8000) atm. It is concluded that self-diffusion does not control the creep of high-purity aluminium at room temperature in the investigated stress and pressure range

Two case studies on the origin of aqueous sulphate in deep crystalline rocks

International Nuclear Information System (INIS)

Michelot, J.L.; Fontes, J.C.

1987-01-01

The paper reports preliminary results obtained from studies in Central Sweden (Stripa) and in Northern Switzerland (Boettstein). The isotopic compositions ( 34 S, 18 O) of dissolved sulphates in shallow and deep groundwaters from the Stripa test site show that (1) the origins of the salinity in the shallow and in the deep groundwaters are probably different, (2) the low sulphate content of the waters collected from the upper part of the deep aquifer system could be derived from the shallow aqueous sulphate through bacterial reduction, (3) a deeper bulk of sulphate can be identified. After examining several hypotheses, a Permian or Triassic origin is attributed to this deep sulphate. Boettstein is the first drilled borehole of the NAGRA (Swiss National Co-operative for the Storage of Radioactive Wastes programme). In the 34 S versus 18 O diagram, most of the representative points of samples collected at different depths (from apparently different water bodies), lie along a straight line. It seems that this line cannot be a reduction line, nor a precipitation line (gypsum or anhydrite). It is thus interpreted as a mixing line. The end members of this mixing line are still unknown. However, a deep brine is present at the bottom of the system, probably related to brines circulating in the Permian channel found at the same depth, a few kilometres away. A working hypothesis involving this deep brine as a source for both end members of the mixing, through two different processes, is presented, with the problem of possible connections between the different water bodies. (author). 16 refs, 5 figs, 2 tabs

Measurement of dynamic wedge angles and beam profiles by means of MRI ferrous sulphate gel dosimetry

Science.gov (United States)

Bengtsson, Magnus; Furre, Torbjørn; Rødal, Jan; Skretting, Arne; Olsen, Dag R.

1996-02-01

The purpose of this study is to examine the possible value of measuring the dose distribution in dynamic wedge photon beams using ferrous sulphate gel phantoms analysed by MRI. The wedge angles and dose profiles were measured for a field size of and for dynamic wedge angles of , , and using a 15 MV photon beam generated from a Clinac 2100 CD (Varian). The dose profiles obtained from MRI ferrous sulphate gel were in good agreement with the dose measurements performed with a diode detector array. Also, the wedge angles determined from the MRI ferrous sulphate gel agreed well with the values obtained by using film dosimetry and with calculations by use of TMS (treatment planning system) (Helax, Uppsala, Sweden). The study demonstrated that MRI ferrous sulphate gel dosimetry is an adequate tool for measurements of some beam characteristics of dynamic radiation fields.

Selection of Suitable Carbon, Nitrogen and Sulphate Source for the Production of Alkaline Protease by Bacillus licheniformis NCIM-2042

Directory of Open Access Journals (Sweden)

Biswanath BHUNIA

2010-06-01

Full Text Available In this study, selection of suitable carbon, nitrogen and sulphate sources were carried out by one-variable-at-time approach for the production of alkaline protease enzyme by Bacillus licheniformis NCIM-2042. Maximum levels of alkaline protease were found in culture media supplemented with magnesium sulphate, starch and soybean meal as a good sulphate, carbon and nitrogen sources which influenced the maximum yield of this enzyme (137.694.57, 135.231.73 and 134.741.77, respectively in comparison with the other sulphate, carbon and nitrogen sources.

Behaviour of Type 316 steel in acidic sulphate solutions at 300-3500C

International Nuclear Information System (INIS)

Newman, J.F.

1987-11-01

Most cation resin beds in service in CEGB power stations, and particularly those in AGR stations, are regenerated with sulphuric acid. Slippage results in trace levels of sulphate passing into the boilers. Previous work has shown that in once-through boilers, feedwater containing 2 μg kg -1 of sulphate could concentrate at localized dry-out sites to form solutions having from 0.1 to 7 wt% of solute. It has been shown also that if the sulphate was present in an acidic solution and it were to be in contact with Type 316 austentitic superheater steel, then intergranular corrosion and intergranular cracking could occur. Previous data, including some unreported results, are tabulated and discussed. The current work had two main objectives. The first was to extend the previous investigations to examine a wider range of acidic sulphate concentrations (as indicated by calculations on the concentration of solute in feedwater), the influence of environment pH, and the effect of sensitization of specimens. The second objective was primarily concerned with elucidating the causes of scatter in the results. This involved examining the influence of electrode potential, the ageing characteristics of the environment, and the method of applying stress to the specimens. (author)

Optimisation of the zinc sulphate turbidity test for the determination of immune status.

Science.gov (United States)

Hogan, I; Doherty, M; Fagan, J; Kennedy, E; Conneely, M; Crowe, B; Lorenz, I

2016-02-13

Failure of passive transfer of maternal immunity occurs in calves that fail to absorb sufficient immunoglobulins from ingested colostrum. The zinc sulphate turbidity test has been developed to test bovine neonates for this failure. The specificity of this test has been shown to be less than ideal. The objective was to examine how parameters of the zinc sulphate turbidity test may be manipulated in order to improve its diagnostic accuracy. One hundred and five blood samples were taken from calves of dairy cows receiving various rates of colostrum feeding. The zinc sulphate turbidity test was carried out multiple times on each sample, varying the solution strength, time of reaction and wavelength of light used and the results compared with those of a radial immunodiffusion test, which is the reference method for measuring immunoglobulin concentration in serum. Reducing the time over which the reaction occurs, or increasing the wavelength of light used to read the turbidity, resulted in decreased specificity without improving sensitivity. Increasing the concentration of the zinc sulphate solution used in the test was shown to improve the specificity without decreasing sensitivity. Examination of the cut-off points suggested that a lower cut-off point would improve the performance. British Veterinary Association.

Contradictory effect of chromate inhibitor on corrosive wear of aluminium alloy

International Nuclear Information System (INIS)

Pokhmurskii, V.I.; Zin, I.M.; Vynar, V.A.; Bily, L.M.

2011-01-01

Research highlights: → Corrosive wear of aluminium alloy in inhibited artificial acid rain was studied. → Tribometer with linear reciprocating ball-on-flat geometry was used.→ Corrosion potential, polarization current and friction coefficient were measured. → Chromate decreases corrosion of aluminium alloy under wear conditions. → Chromate in general accelerates corrosive wear of the alloy in acid rain. - Abstract: The corrosive wear of D16T aluminium alloy in artificial acid rain was studied. A special tribometer with the linear reciprocating ball-on-flat geometry was used. The setup allows to measure simultaneously an open circuit potential, to carry out potentiostatic and potentiodynamic polarization studies of the alloy corrosion and to record the friction coefficient. It was established that the addition of strontium chromate inhibitor to the working environment decreases an electrochemical corrosion of the aluminium alloy under wear conditions, but in general accelerates its destruction due to insufficient wear resistance of a formed surface film.

A study of aluminium-exposed fish using a scanning proton microprobe

Energy Technology Data Exchange (ETDEWEB)

Cholewa, M; Legge, G L.F. [Melbourne Univ., Parkville, VIC (Australia). School of Physics; Eeckhaoudt, S; Van Grieken, R [Universitaire Instelling Antwerpen, Antwerp (Belgium)

1994-12-31

A major problem has arisen in Europe with the depopulation of fresh water fish in lakes and streams collecting acid rain. The sensitivity to acidification is species specific and appears to be associated with metal levels. The Scanning Proton Microprobe (SPMP) at the Micro Analytical Research Centre of the University of Melbourne was used to study the subcellular distribution of aluminium and other elements in the gills of fish exposed to acidified water with elevated Al-levels. Experiments were performed on thin sections taken from fish exposed to media with different pH and aluminium concentration. Aluminium was found on the surface of the gill lamellae, but also inside the tissue. Bulk analysis of the gills showed much higher concentrations in the aluminium-exposed fish, compared to the control ones, but no information regarding the actual accumulation sites can be inferred. Extensive study of damage done to the sample by intense proton beams during elemental analysis was performed with scanning transmission ion microscopy. 3 refs., 3 figs.

A study of aluminium-exposed fish using a scanning proton microprobe

Energy Technology Data Exchange (ETDEWEB)

Cholewa, M.; Legge, G.L.F. [Melbourne Univ., Parkville, VIC (Australia). School of Physics; Eeckhaoudt, S.; Van Grieken, R. [Universitaire Instelling Antwerpen, Antwerp (Belgium)

1993-12-31

A major problem has arisen in Europe with the depopulation of fresh water fish in lakes and streams collecting acid rain. The sensitivity to acidification is species specific and appears to be associated with metal levels. The Scanning Proton Microprobe (SPMP) at the Micro Analytical Research Centre of the University of Melbourne was used to study the subcellular distribution of aluminium and other elements in the gills of fish exposed to acidified water with elevated Al-levels. Experiments were performed on thin sections taken from fish exposed to media with different pH and aluminium concentration. Aluminium was found on the surface of the gill lamellae, but also inside the tissue. Bulk analysis of the gills showed much higher concentrations in the aluminium-exposed fish, compared to the control ones, but no information regarding the actual accumulation sites can be inferred. Extensive study of damage done to the sample by intense proton beams during elemental analysis was performed with scanning transmission ion microscopy. 3 refs., 3 figs.

Process Simulation of Aluminium Sheet Metal Deep Drawing at Elevated Temperatures

International Nuclear Information System (INIS)

Winklhofer, Johannes; Trattnig, Gernot; Lind, Christoph; Sommitsch, Christof; Feuerhuber, Hannes

2010-01-01

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.

A study of aluminium-exposed fish using a scanning proton microprobe

International Nuclear Information System (INIS)

Cholewa, M.; Legge, G.L.F.

1993-01-01

A major problem has arisen in Europe with the depopulation of fresh water fish in lakes and streams collecting acid rain. The sensitivity to acidification is species specific and appears to be associated with metal levels. The Scanning Proton Microprobe (SPMP) at the Micro Analytical Research Centre of the University of Melbourne was used to study the subcellular distribution of aluminium and other elements in the gills of fish exposed to acidified water with elevated Al-levels. Experiments were performed on thin sections taken from fish exposed to media with different pH and aluminium concentration. Aluminium was found on the surface of the gill lamellae, but also inside the tissue. Bulk analysis of the gills showed much higher concentrations in the aluminium-exposed fish, compared to the control ones, but no information regarding the actual accumulation sites can be inferred. Extensive study of damage done to the sample by intense proton beams during elemental analysis was performed with scanning transmission ion microscopy. 3 refs., 3 figs

Study of Surface Roughness and Cutting force in machining for 6068 Aluminium alloy

Science.gov (United States)

Purushothaman, D.; Kaushik Yanamundra, Krishna; Krishnan, Gokul; Perisamy, C.

2018-04-01

Metal matrix composites, in particular, Aluminium Hybrid Composites are gaining increasing attention for applications in air and land because of their superior strength to weight ratio, density and high temperature resistance. Aluminium alloys are being used for a wide range of applications in Aerospace and Automobile industries, to name a few. The Aluminium Alloy 6068 has been used as the specimen. It is mainly composed of Aluminium (93.22 - 97.6 %), Magnesium (0.60 - 1.2 %), Silicon (0.60 - 1.4 %) and Bismuth (0.60 - 1.1 %). Aluminium 6068 is widely used for manufacturing aircraft structures, fuselages and wings. It is also extensively used in fabricating automobile parts such as wheel spacers. In this study, tests for the measurement of surface roughness and cutting force has been carried out on the specimen, the results evaluated and conclusions are drawn. Also the simulation of the same is carried out in a commercial FE software – ABAQUS.

The quality of our drinking water: aluminium determination with an acoustic wave sensor.

Science.gov (United States)

Veríssimo, Marta I S; Gomes, M Teresa S R

2008-06-09

A new methodology based on an inexpensive aluminium acoustic wave sensor is presented. Although the aluminium sensor has already been reported, and the composition of the selective membrane is known, the low detection limits required for the analysis of drinking water, demanded the inclusion of a preconcentration stage, as well as an optimization of the sensor. The necessary coating amount was established, as well as the best preconcentration protocol, in terms of oxidation of organic matter and aluminium elution from the Chelex-100. The methodology developed with the acoustic wave sensor allowed aluminium quantitation above 0.07 mg L(-1). Several water samples from Portugal were analysed using the acoustic wave sensor, as well as by UV-vis spectrophotometry. Results obtained with both methodologies were not statistically different (alpha=0.05), both in terms of accuracy and precision. This new methodology proved to be adequate for aluminium quantitation in drinking water and showed to be faster and less reagent consuming than the UV spectrophotometric methodology.

Ultraviolet Plasmonic Aluminium Nanoparticles for Highly Efficient Light Incoupling on Silicon Solar Cells

Directory of Open Access Journals (Sweden)

Yinan Zhang

2016-05-01

Full Text Available Plasmonic metal nanoparticles supporting localized surface plasmon resonances have attracted a great deal of interest in boosting the light absorption in solar cells. Among the various plasmonic materials, the aluminium nanoparticles recently have become a rising star due to their unique ultraviolet plasmonic resonances, low cost, earth-abundance and high compatibility with the complementary metal-oxide semiconductor (CMOS manufacturing process. Here, we report some key factors that determine the light incoupling of aluminium nanoparticles located on the front side of silicon solar cells. We first numerically study the scattering and absorption properties of the aluminium nanoparticles and the influence of the nanoparticle shape, size, surface coverage and the spacing layer on the light incoupling using the finite difference time domain method. Then, we experimentally integrate 100-nm aluminium nanoparticles on the front side of silicon solar cells with varying silicon nitride thicknesses. This study provides the fundamental insights for designing aluminium nanoparticle-based light trapping on solar cells.

Investigating the Changes of Sulphate in Potabale Water of Yasuj City and preparing it's Qualitative Plan by Means of GIS Tools

International Nuclear Information System (INIS)

Pasereh, F.; Hasani, A.; Hoseini, N.; Javid, A.

2016-01-01

Water has always some soluble salts, such as sulphate. Sulphate enters the water through different resources such as, dissolved gypsum, waste water of industrial factories and automobiles smoke, dissolved in rain. Presence of sulphate in potable water has an enormous role in creating constant hardness.On the other hand Presence of sulphate with high density in drinking water, causes changes in taste and it's combination with Calcium and Magnesium anions has laxative effect. The goal of this study is to assess the amount of existing sulphate in Yasuj city potable ground water, and determining the procedure of changes in chemical parameters of sulphate and recognizing effective factors on these parameters and preparing qualitative plan for water resources for sulphate parameter by means of GIS tools. Method: In the study described above, 42 specimens in the 7 early months of the year 1387 were acquired and tested. Sulphate tests were done based on the measuring method of the instrument of Filter photometer (Model: 7000). For analysing the results, Excel software and for preparing qualitative plan, GIS software was used. Findings: This study showed that sulfate levels in water resources by reducing water level in summer and autumn and with a water level of under ground water resources increases. Discussion and Conclusion: Decrease of ground water resources of Yasuj city, causes the sulphate density to increase.

Aluminium and energy. An interview

Energy Technology Data Exchange (ETDEWEB)