AlCl3 Concentration Research Articles

Effects of aluminium on ATP pools and utilization in the cyanobacterium Anabaena cylindrica: a model for the in vivo toxicity

ATP pools extracted from the cyanobacterium Anabaena cylindrica, grown in the absence or presence of AlCl3, were measured using the luciferin‐luciferase assay. Addition of low concentrations of AlCl3 (3.6–36 μM) increased the ATP pool 20–40% within 24 h, the effect being more marked with time. When using the Tris‐EDTA boiling technique for extraction of cellular ATP, the ATP from aluminium‐exposed cells appeared more stable during the extraction than the ATP from untreated cells. The higher ATP pools in aluminium‐exposed cells were also evident after dark treatment and addition of the phosphorylating inhibitors carbonylcyanide m‐chloro‐phenylhydrazone (CCCP) and N,N‐dicyclohexylcarbodiimide (DCCD). The formation of elevated ATP pools in cells exposed to aluminium was curtailed by high concentrations of cellular phosphate and postincubation at high pH (>8). These results favour the hypothesis that intracellular aluminium binds to ATP by competing with Mg2+ and, as a consequence, the stable Al3+‐ATP complex formed is no longer available for cellular metabolism. The cyanobacterium is assumed to compensate by increasing the total pool of ATP. At high AlCl3‐concentrations, and in particular at low phosphate: aluminium molar ratios (<1), aluminium apparently also interferes with the membranes in A. cylindrica as indicated by inhibited O2 production, reduced ATP production and cell lysis.

Studies on catalytic dealkylation of lignite: effect on structure and solubility

Kutch lignite has been dealkylated by treatment with various concentrations of AlCl 3 at different temperatures. Dealkylation was confirmed by comparison of infrared spectra and measurement of specific optical densities. Characteristics of the lignite and the treated samples, including H C ratios and solubilities in solvents, were determined and compared.

Aluminum Increases Agonist‐Stimulated Cyclic AMP Production in Rat Cerebral Cortical Slices

The effects of AlCl3 on basal and stimulated cyclic AMP production in rat cerebral cortical slices were studied. AlCl3 (10-250 microM) had no effect on the cyclic AMP concentration in the absence of drugs that stimulate the synthesis of cyclic AMP. 2-Chloroadenosine (25-200 microM) significantly stimulated the synthesis of cyclic AMP in a concentration-dependent manner, and AlCl3 significantly potentiated this response at 50 and 100 microM 2-chloroadenosine. This effect of AlCl3 was dependent on preexposure of the slices to AlCl3 before addition of the agonist. The potentiation by AlCl3 of the 2-chloroadenosine-induced increase in cyclic AMP level was concentration dependent, with significant enhancement by 100 (142% of the control) and 250 (150% of the control) microM AlCl3. Lower concentrations of AlCl3 had no significant effect on the production of cyclic AMP stimulated by 2-chloroadenosine. AlCl3 also potentiated the isoproterenol-induced increase in cyclic AMP production. Forskolin-induced production of cyclic AMP was unaltered by the presence of AlCl3. These results demonstrate that AlCl3 can potentiate agonist-stimulated cyclic AMP production in a whole-cell brain preparation without the addition of fluoride. This may account for the previously reported aluminum-induced increase in cyclic AMP concentrations in rat brain in vivo.

Raman and infrared spectroscopy of the AlCl3–SOCl2 system

The structural aspects of the AlCl3–SOCl2 system have been examined by vibrational spectroscopy. The SOCl2 molecule exhibits amphoteric character, i.e. it can act simultaneously as a donor through the oxygen atom and as an acceptor through the sulphur atom. The liquid state contains loosely bound, open-chain dimers/oligomers, (Cl2SO)n with n 2. The dissolution of Al2Cl6 in SOCl2 occurs dissociatively with the formation of Cl2SO → AlCl3 adducts. At higher AlCl3 concentrations, an increase in solution electrical conductivity is attributed to the reaction: 2Cl2SO → AlCl3⇌[Cl2Al(â†� OSCl2)2]++ AlCl–4

AlF4- reversibly inhibits 'P'-type cation-transport ATPases, possibly by interacting with the phosphate-binding site of the ATPase.

The only known cellular action of AlF4- is to stimulate the G-proteins. The aim of the present work is to demonstrate that AlF4- also inhibits 'P'-type cation-transport ATPases. NaF plus AlCl3 completely and reversibly inhibits the activity of the purified (Na+ + K+)-ATPase (Na+- and K+-activated ATPase) and of the purified plasmalemmal (Ca2+ + Mg2+)-ATPase (Ca2+-stimulated and Mg2+-dependent ATPase). It partially inhibits the activity of the sarcoplasmic-reticulum (Ca2+ + Mg2+)-ATPase, whereas it does not affect the mitochondrial H+-transporting ATPase. The inhibitory substances are neither F- nor Al3+ but rather fluoroaluminate complexes. Because AlF4- still inhibits the ATPase in the presence of guanosine 5'-[beta-thio]diphosphate, and because guanosine 5'-[beta gamma-imido]triphosphate does not inhibit the ATPase, it is unlikely that the inhibition could be due to the activation of an unknown G-protein. The time course of inhibition and the concentrations of NaF and AlCl3 required for this inhibition differ for the different ATPases. AlF4- inhibits the (Na+ + K+)-ATPase and the plasmalemmal (Ca2+ + Mg2+)-ATPase noncompetitively with respect to ATP and to their respective cationic substrates, Na+ and Ca2+. AlF4- probably binds to the phosphate-binding site of the ATPase, as the Ki for inhibition of the (Na+ + K+)-ATPase and of the plasmalemmal (Ca2+ + Mg2+)-ATPase is shifted in the presence of respectively 5 and 50 mM-Pi to higher concentrations of NaF. Moreover, AlF4- inhibits the K+-activated p-nitrophenylphosphatase of the (Na+ + K+)-ATPase competitively with respect to p-nitrophenyl phosphate. This AlF4- -induced inhibition of 'P'-type cation-transport ATPases warns us against explaining all the effects of AlF4- on intact cells by an activation of G-proteins.

A new bath for the electrodeposition of aluminium. III. The electrochemical behaviour of the rotating aluminium disc electrode in pure AlCl3/THF-toluene solutions

The electrochemical behaviour of the rotating aluminium disc electrode in AlCl3/tetrahydrofurantoluene solution was studied. The kinetic parameters controlling the electrode processes were investigated. The effect of the concentration of AlCl3, the speed of rotation of the rotating disc electrode and the temperature on the cathodic and anodic current density was analysed. The results were compared with those for AlCl3−LiAlH4/THF-toluene solutions.

Theoretical and experimental study of subsurface burnout and ESD in GaAs FETs and HEMTs : F. A. Buot, W. T. Anderson, A. Christou and K. J. Sleger. Annual Proceedings of the Reliability Physics Symposium, San Diego, U.S.A., p. 181 (1987)

The effect of aluminium (Al) on phosphoinositide-specific phospholipase C (PLC) and lipid kinase activities was examined in a cellular suspension of coffee. Two main effects were seen when cells were treated with AlCl3. In periods as short as 1 minute, Al-exposed cells increased the activity of PLC and IP3 formation up to two fold. Over longer periods PLC activity was inhibited by more than 50 percnt;. The activity of phosphatidylinositol 4-kinase (PI 4-K), phosphatidylinositol phosphate 5-kinase (PIP 5-K) and diacylglycerol kinase increased when cells were incubated in the presence of different concentrations of AlCl3. The present study reports for the first time that Al may have different effects on the PI-signaling pathway depending on the time of exposure. Our results strongly support the hypothesis that Al disrupts the metabolism of membrane phospholipids regulating not only PLC but also other enzymes that have key roles in signal-transduction pathways.

Aluminum impairs glucose utilization and cholinergic activity in rat brain in vitro

The effects of AlCl 3 on the production of 14CO 2 from [U- 14C] glucose and high affinity choline transport in rat brain synaptosomes, and on carbachol-stimulated hydrolysis of phosphoinositides in cortical slices were studied. In buffer containing either high K + (50 mM) or low K + (4.9 mM), 1 mM AlCl 3 significantly depressed the synaptosomal production of 14CO 2 from [U- 14C]-glucose to 54% and 44% of control rates, respectively. At a concentration of 0.1 mM, AlCl 3 depressed the evolution of 14CO 2 from [U- 14C]glucose from synaptosomes incubated in the high K + buffer, but did not significantly change 14CO 2 production from synaptosomes in the low K + buffer. Aluminum chloride also inhibited high affinity choline transport in synaptosomes prepared from rat cortex and from hippocampus with an IC 50 of approximately 0.5 mM. In brain slices the carbachol-stimulated hydrolysis of phosphoinositides was inhibited by AlCl 3 in a dose-dependent manner. One millimolar, 0.5 mM and 0.1 mM AlCl 3 inhibited the carbachol-stimulated release of inositol phosphates by 75%, 44% and 33%, respectively. These same concentrations of AlCl 3 inhibited the incorporation of [ 3H] inositol into phospholipids. This inhibitory effect was not dose-dependent as all 3 concentrations of AlCl 3 inhibited phospholipid labelling to the same extent (27–37%). These results are discussed in relation to the in vivo neurotoxicity of aluminum.

The in vivo cross-linking of proteins and DNA by heavy metals.

Cross-linking of proteins to DNA in live, intact Novikoff ascites hepatoma cells exposed in vitro to different concentrations of CuSO4, Pb(NO3)2, HgCl2, and AlCl3 was studied. Protein-DNA complexes were separated by high-speed centrifugation of cells solubilized in buffered 4% sodium dodecyl sulfate and assayed by electrophoretic separation of proteins associated with the DNA-containing pellets. Concentration dependence experiments showed that the optimal cross-linking occurred at metal concentration of 0.5 mM for CuSO4, HgCl2, and AlCl3 while the optimal cross-linking for Pb(NO3)2 was at 5 mM. For some metals at concentrations higher than optimal, the amounts of cross-linked proteins decreased significantly. Immunochemical analysis of the cross-linked proteins using antibodies to matrix, chromatin, lamins, and cytokeratin fractions demonstrated that some, but not all, members of these protein families became cross-linked to the DNA. Each metal exhibited a cross-linking pattern of its own, different from those of the other metals. Radioactive labeling experiments showed that all the metals tested became associated with the DNA-protein pellets within 1 h after their addition to the incubation medium. However, hexavalent chromium required more than 2 h before appearing in the DNA-protein pellets in significant amounts.

X-ray diffraction analysis of molten AlCl3–NaCl system

The way in which structure of molten AlCl3–NaCl mixtures changes with AlCl3 concentration and temperature has been investigated by x-ray diffraction analysis. It was confirmed that AlCl4 tetrahedra are the fundamental structural units in the mixture of 50–70 mol % AlCl3. The nearest-neighbor distance of the Al–Cl, Na–Cl, and Cl–Cl pairs were 2.13, 2.80, and 3.48 Å, respectively. It was considered that the variation of the Q ⋅ i(Q) curves with AlCl3 concentration is due to the change of the mole ratio of AlCl−4 to Al2Cl−7 and the effect of the Na–Cl pair. It was supposed that AlCl−4 is tetrahedral and Al2Cl−7 is constructed from two corner-sharing AlCl4 tetrahedra. Both the concentration of Al2Cl−7 and the coordination number of Cl around an Na increased with increasing AlCl3 concentration at constant temperature, but decreased with increased temperature. The structure of the melt changed with variation of temperature at constant AlCl3 concentration.

A study of the voltage and current efficiencies of fused salt AlCl3 electrolysis using bench scale cells

AbstractThe fused salt electrolysis of AlCl3 dissolved in LiCl‐NaCl melts at 700°C was studied using bench scale cells employing graphite electrodes. The effects of AlCl3 concentration, forced convection, interelectrode spacing, and current density on the voltage, current, and energy efficiencies of the process were investigated. At a practical cell voltage of 3.05 V and current density of 15 kA·m−2 the electrical energy consumption per kg of aluminum produced by the AlCl3 process was about 32 MJ, compared with a typical value of 52 MJ·kg−1 for the Hall‐Héroult electrolysis.

Gel properties of a protein fraction of Vicia faba in dependence on some influencing factors

AbstractThe shear modulus of Vicia faba protein gels formed by thermal denaturation can be lowered by increasing the pH value and the sunflower oil concentration, it can be increased by increasing concentrations of NaCl, CaCl2, AlCl3, glucose, sucrose, and starch. These changes of the shear modulus are connected with a shift of the ratio of the plastic component of the gels to an elastic one.

Analysis on formation process of ultrafine alumina particle from NH3 gas-AlCl3 solution.

It was reported that the ultrafine particles of alumina was prepared by the neaction of NH3 gas and AlCl3 solution. A particle size decreased with decreasing NH3 gas composition or AlCl3 concentration. The particles of less than 50Å in size were prepared.The formation mechanism was discussed as follows. While a mass of AlCl3 solution falls from the top to the bottom of a stream in a flask, NH3 gas is absorbed from the surface of a mass. The generation zone on the surface of solution defined in preceding paper shifts toward the innerpart of mother liquid during the very short exposure time for NH3 gas, so that the ultrafine particles and excess OH- ions remain in the stocking zone behind the generation zone. The particles and OH- ions are carried into the mother liquid by the stream in the flask and the excess OH- ions make the relatively large particles by inhomogeneous reaction with Al3+ ions there. The partcles exist in the mother liquid as a stable colloid for the very near equilibrium state of the mother liquid.

溶融LiCl-NaCl-AlCl<SUB>3</SUB>3成分系の電気伝導度

Electrical conductivity of LiCl-NaCl-AlCl3 ternary melts has been measured over the composition range of less than 50 mol% AlCl3 and the temperature range of 800∼1200 K by using the conductivity cell made of quartz.\ oindentThe results obtained are summarized as follows:The conductivity of the ternary melt decreases with an increase in AlCl3 content, and in the composition range of less than about 40 mol% AlCl3, the conductivity increases with increasing ratio of the LiCl to NaCl content. The conductivity was expressed as a function of temperature and composition.By regarding the ternary melt as a reciprocal melt of (Li+, Na+||Cl−, AlCl4−), the equivalent conductivity and the activation energy for conductance were calculated. The equivalent conductivity shows a minimum value at the cationic fraction of Na+ from 0.6 to 0.9 and the anionic fraction of AlCl4− from 0.1 to 0.3. Also the equivalent conductivity showsa slight negative deviation from additivity for the cationic fraction, and a large deviation for the anionic fraction. The activation energy for conductance remains nearly constant for the cationic fraction, but exhibits a remarkable variation for the anionic fraction and shows a maximum value at about 0.2 of the anionic fraction of AlCl4−.For industrial purposes, the LiCl-NaCl-AlCl3 ternary melt may be used for the electrolytic bath of aluminum due to its high conductivity. However, it is necessary to keep the concentration of AlCl3 in the melt constant because the conductivity varies greatly with AlCl3 content, particularly in the region of low AlCl3 content.

Effect of 2,4-D and Various Salts on Eurasian Watermilfoil

The management of Eurasian watermilfoil, an inimical aquatic weed in the Tennessee Valley, involves the use of water level management and herbicidal treatment with 2,4-D [(2,4-dichlorophenoxy)acetic acid]. The possible use of other chemicals to make 2,4-D more effective was tested by measuring growth of Eurasian watermilfoil under laboratory conditions with combinations of sublethal levels of 2,4-D and partially inhibitory concentrations of AlCl3, NH4Cl, Na2AsO2, BaCl2, Na2B4O7, CuSO4, HgCl2, Pb(NO3)2, NaCl, and ZnSO4. At the levels tested, BaCl2, Pb(NO3)2, and ZnSO4were only additive in effect with 2,4-D. Other compounds produced synergism at some concentrations and mutual antagonism at other levels. The greatest synergism was obtained by using HgCl2, AlCl3, and NaCl at 0.2 μM, 10.0 μM, and 200.00 mM respectively.

Exchange Adsorption of Trace Quantities of Cadmium in Soils Treated with Chlorides of Aluminum, Calcium and Sodium

AbstractThe exchange adsorption of Cd has been studied in Cecil sandy loam (clay fraction 45% kaolinite and 25% vermiculite), Winsum clay loam (clay fraction 80% illite), and Yolo silt loam (clay fraction 47% montmorillonite and 22% mica). Experimental variables were the major cations Al3+, Ca2+, and Na+, salt (chloride) levels (from 5 to 50 meq/liter), and the initial concentration of CdCl2 (from 22 to 170 µeq/liter). The exchange of Cd2+ in Al3+‐ and Ca2+‐treated soils was normal in that the adsorption was greater in the presence of Ca2+ than of Al3+, and decreased with increasing concentration of AlCl3 or CaCl2. In the Na+‐treated, alkalized soils, Cd2+ did not precipitate. The exchange was unusual because the adsorption of Cd2+ decreased as NaCl concentrations decreased. The same behavior was shown by 109Cd2+. At NaCl concentrations decreasing below 30 meq/liter, the adsorption of Ca2+ by Na+‐treated soils also decreased, as did the adsorption of Na+. The result was attributed to decreasing soil exchange capacity with decreasing NaCl concentration due to increased adsorption of products derived from alkaline corrosion of the soil matrix.

Studies on pit formation on aluminum immersed in artificial waters(2nd report)

Aluminum sheet (Fe = 0.072%, Si = 0.037%, and Al = balance) was immersed in artificial water, LSW 1 (water for forming macro-pits) and macro-pits were formed on the aluminum surface.The composition of LSW 1 was composed of Na2SiO3 (5ppm of SiO32-) + NaCl (5ppm of Cl-) + pure water, and its pH value was 9.39.5.The formation of macro-pits consisted of 5 stages as follows.First stage: Microstructure of α (FeSi) contained in aluminum could not be observed by microscopy.Second stage:Microstructure of α (FeSi) was observed by microscopy, because of the dissolution of passive film on α (FeSi). It was proved by the weight decreases of the specimen after immersion and after the removal of the film.Third stage: Formation of macro-pits was observed around α (FeSi).Fourth stage: Etch pits, crystallographic or cubic corrosions was observed near α (FeSi).Fifth stage: Macro-pits were observed in the centre of the aggregate of etch pits. The formation of etch pits on the surface was proved by etching of aluminum by the etching solution (the composition was LSW 1 + any concentration of AlCl3) at pH 1.82.7(corresponding to 15.34.6% of AlCl3 concentration).As the results of these experiments, the formation of macro-pits on the aluminum sheet was presumed as follows:The thiner passive film covering α (FeSi) was dissolved by LSW 1, while, remainder parts of specimen surface being coverd with the passive film.Aluminium around naked α (FeSi) particles becomes anode and micro-pits, are generated. At selected points (somewhere among micro-pits) etch pits are generated as a result of etching the aluminum surface by the solution with spontaneous high concentration of AlCl3 resulted from dissolving aluminum. Therefore, necessary conditions generating macro-pit are presumed: existence of Cl-, and trace of inhibitor (SiO32-), thiner passive film covering on α (FeSi), and high pH of the artificial water(LSW 1).

Gel Strength of Kappa‐Carrageenan as Affected by Cations

SUMMARY– Kappa carrageenan was ion‐exchanged with Al+3, NH4, +2, Ca+2, Fe+3, Fe+3, Mg+2, Na+2 and Sn+2. The gelling temperature and gel strength were determined for 1% exchanged kappa carrageenan gels prepared with 0.0375,0.075 and 0.15 N solutions of each of the exchanging cations; 1% exchanged kappa carrageenans with 0.0375, 0.075 and 0.15 N KCI, and non‐exchanged kappa carrageenan with the same concentrations of AlCl3, NH4Cl, CaCl2, FeCl2, FeCl3 MgCl2 KCl, NaCl and SnCl2.Ion‐exchange with Al, Fe+2, Fe+3 and Sn prevented gel formation. The other ion‐exchanged carrageenans had signicantly lower gel strength than the non‐exchanged carrageenan in a corresponding cation solution. Furthermore, the Mg‐ and Ca‐exchanged carrageenans had greater gel strengths than the NH4 and Na‐carrageenans. Use of KCI with the NH,‐, Ca‐, Mg‐ and Na‐exchanged carrageenan resulted in increased gel strength, but the Al, Fe+2, Fe+3 and Sn‐exchanged carrageenans still did not form a gel. The rank order of the gel strength of the NH4, Ca‐, Mg‐ and Na‐exchanged carrageenan dispersed in KCI was similar for the exchanged carrageenan in solutions of the exchanging cation, but the gelling temperatures and gel strength of the former approached that of the non‐exchanged carrageenan in similar concentrations of KCl.For the non‐exchanged carrageenan at the 0.075 N level of salt concentration, the effect of cation was K > Ca, Mg > Fe+2, NH4 < Na, Sn < Fe+3, Al (P < 0.001). Use of increasing concentrations of NH,Cl, NaCl, KCl and SnCl2 resulted in increased gel strength, whereas increasing concentrations of CaCl2, FeCl3 and MgCl2 decreased gel strength. These differences were reflected in a slightly different rank order for the 0.15 N level of salt.

THE INFLUENCE OF ELECTROLYTES UPON THE ELECTROPHORETIC MIGRATION OF BACTERIA AND OF YEAST CELLS

1. It seems first of all clear from our results that the effect of electrolytes upon electrophoretic charge is essentially the same, whether one is dealing with silica dust, bacteria, or yeast cells, although certain quantitative differences appear which will later be discussed. 2. The normal negative charge on the suspended particles appears to be slightly increased by very low concentrations of electrolytes, markedly so in the case of yeast cells. Increase in charge due to minimal concentrations of electrolytes has been recorded by Loeb (1922) for collodion particles. 3. Higher concentrations of electrolytes cause a marked and progressive decrease in negative charge, sometimes leading to an isopotential condition and sometimes to a complete reversal of charge with active migration toward the cathode. This effect is apparently due to the cation alone and increases with the valency of the cation, except that the H ion shows specially marked activity, between that of bivalent and trivalent ions. Since NaOH behaves like an ordinary univalent salt, increased alkalinity of a solution does not further depress the charge already depressed by salts; but, since the H ion is much more active than other univalent or bivalent ions, increased acidity does cause a further progressive depression of charge, even in salt solutions. Certain electrolytes appear to show individual peculiarities due to something else than their valency. Thus KCl for example is distinctly more effective than NaCl. Sodium chloride in general appears to exert less influence upon electrophoretic charge, either in low or high dilution, than do other compounds of univalent ions studied. This depressing effect of moderately high concentrations of electrolytes is much less marked with yeast cells than with Bacterium coli. Silica dust is still less affected by monovalent and bivalent ions than are the yeast cells but appears to be more affected than either yeast or Bacterium coli by AlCl(3). 4. Very high concentrations of AlCl(3) (above 10(-2)M) show a third effect, a decrease of the positive charge produced by concentrations of moderate molar strength. This is analogous to phenomena observed for trivalent salts by Northrop and De Kruif (1921-22) and for acid by Winslow, Falk, and Caulfield (1923-24). 5. Organic substances, such as glucose, glycerol, and saponin produce no effect on electrophoretic velocity until they reach a concentration at which viscosity changes are involved. 6. The first two results observed,-(a) the increase in charge as a result of slight additions of electrolytes, and (b) the marked decrease in charge with further concentration of electrolytes, depending on the valency of the cation, so far as vegetable cells are concerned, are entirely in accord with the theory of the Donnan equilibrium as worked out by Loeb (1922). We might assume in explaining such phenomena that the plant cell contains a certain proportion of unbound protein material and that the first modicum of cation which enters the cell is bound by the protein, leading to an increase in the relative negative charge of the cell as compared with its menstruum, while subsequent increments of cation remain unbound in the cell and thus lower its charge. When we find, however, that the same phenomena are apparent with collodion particles, as shown by Loeb, and with silica dust, it seems difficult to apply such a theory, involving the conceptions of a permeable membrane and unbound organic compounds. Loeb (1923-24) suggests that the primary increase may be due to an aggregation of anions in the part of the electrical double layer adjacent to the suspended particles; but why there should be first an aggregation of anions and later (with increasing concentration) an aggregation of cations, is not easy to conceive. The third result,-the reversion to a more negative charge in the presence of a marked excess of trivalent ions,-is again difficult to explain. Loeb, in this connection, postulates the existence of complex ion-protein compounds, which can scarcely be assumed in the case of the silica particles.