AlCl3 Solution Research Articles

ALUMINA MATRIX WITH CONTROLLED MORPHOLOGY FOR COLORED SPECTRALLY SELECTIVE COATINGS

This study presents the results obtained in tailoring thin films of alumina, deposited onto aluminium substrates by spray pyrolysis, at 250.C, using AlCl3 solutions (0.15M) in a water:ethanol (1:1) solvent mixture. As morphology controlling agents, acetylacetone and maleic acid based copolymers are added in the precursors solutions. The precursors systems are analyzed by FTIR spectroscopy and the surface morphology of alumina thin films is investigated by atomic force microscopy. The addition of hydrophilic copolymer in precursors solution favors the development of regular open structures, while fractured large open structures are obtained when hydrophobic copolymer is used. The addition of acetylacetone in spraying solution leads to irregular large open structures. Combined additive systems (acetylacetone and hydrophylic/hydrophobic copolymers) have a complex influence and can be a tool in tailoring the morphology of the alumina thin films, as suitable matrix for further infiltration of red (Fe2O3) and gray-green (CuxS) pigments and development of colored solar selective absorber coatings with promising optical performances. Thus, spectral selectivities (S) of 3.4 - 4.07 are obtained for red absorber coatings, while for gray-green absorber coatings spectral selectivities are slightly lower (S = 2.35 - 2.7).

MiR319, miR390, and miR393 Are Involved in Aluminum Response in Flax (Linum usitatissimum L.).

Acid soils limit agricultural production worldwide. Major reason of crop losses in acid soils is the toxicity of aluminum (Al). In the present work, we investigated expression alterations of microRNAs in flax (Linum usitatissimum L.) plants under Al stress. Flax seedlings of resistant (TMP1919 and G1071/4_k) and sensitive (Lira and G1071/4_o) to Al cultivars and lines were exposed to AlCl3 solution for 4 and 24 hours. Twelve small RNA libraries were constructed and sequenced using Illumina platform. In total, 97 microRNAs from 18 conserved families were identified. miR319, miR390, and miR393 revealed expression alterations associated with Al treatment of flax plants. Moreover, for miR390 and miR393, the alterations were distinct in sensitive and resistant to Al genotypes. Expression level changes of miR319 and miR390 were confirmed using qPCR analysis. In flax, potential targets of miR319 are TCPs, miR390–TAS3 and GRF5, and miR393–AFB2-coding transcripts. TCPs, TAS3, GRF5, and AFB2 participate in regulation of plant growth and development. The involvement of miR319, miR390, and miR393 in response to Al stress in flax was shown here for the first time. We speculate that these microRNAs play an important role in Al response via regulation of growth processes in flax plants.

Enhanced defluoridation using reusable strong acid cation exchangers in Al3+ form (SAC-Al) containing hydrated Al(III) oxide nanoparticles

Currently used metal oxide based fluoride selective sorbents exhibit low sorption capacity, especially at near neutral to mildly alkaline pH (6.5–8.5) of typical fluoride-contaminated groundwater. The present study demonstrates a novel reusable strong acid cation preloaded in Al3+ form containing hydrated Al(III) oxide (HAlO) nanoparticles (SAC-Al) that can treat the fluoride across the pH range of groundwater with a simple regeneration capability. Once the cation exchange takes place (i.e., hardness cations namely Ca2+ displaces the Al3+ ions from the SAC-Al, the aluminum ions undergo hydrolysis reaction and simultaneously form HAlO nanoparticles onto the matrix of SAC-Al. Fluoride is then specifically removed from aqueous phase through Lewis acid-base interactions with freshly precipitated HAlO nanoparticles. Moreover, protons (H+) produced during the aluminum hydrolysis can promote acidic condition in the resin phase resulting in higher sorption affinity between HAlO and fluoride ions. From the experimental column runs, the hybrid material can remove fluoride below WHO recommended levels (1.5mg/L) for more than 400 bed volumes (BV) of mildly alkaline influent (5mg F/L, pH 8.0) and was stable for more than five exhaustion-regeneration cycles, over 2x greater performance than activated alumina (200 BV). The exhausted material can be efficiently regenerated by passing only stoichiometric amounts of diluted 2% AlCl3 solution. The results from SEM-EDX, TEM, and XRD techniques confirm that the aluminum was dispersed throughout the SAC resin as an amorphous hydrated Al(III) oxide nanoparticles.

Tolerance to heavy metal stress in seedlings of three pine species from contrasting environmental conditions in Chile

Tolerance to metal stress was studied in seedlings of three pine species (Pinus radiata, P. pinaster and P. canariensis) under controlled ex vitro conditions. Mature female cones were randomly collected at two sites in Chile (Llico and Huilquilemu) characterized by contrasting environmental conditions. One-year-old pine seedlings were immersed in trays with solutions of CuSO4 (300 mM) or AlCl3 (100 mM), and their survival, growth rate and decay symptoms were recorded for 60 days. Results showed large differences among provenances in seedling tolerance to CuSO4 and AlCl3 in terms of survival and growth. Multivariate analysis revealed a significant association (p <0.0001) between the first canonical function and the following variables: provenance, species, metal stress and growing rate, as well as between the second canonical function and provenance, species, metal stress and symptomatology, indicating a high degree of genotype-environment interaction. Moreover, the activity of POX, SOD and CAT enzymes was determined 60 days after the beginning of the experiment in the Llico provenance seedlings. P. pinaster showed the highest activity level for all the enzymes considered, while P. canariensis and P. radiata had intermediate and lowest values, respectively. Differential gene expression among pine seedlings under metal stress with CuSO4 for two genes (Cu-Zn-superoxide dismutase and RuBisCo) confirmed P. pinaster as the most tolerant species to CuSO4 treatment. Our results are consistent with the hypothesis that abiotic stress in the maternal environment can induce a “transgenerational plasticity” which could affect progeny performances. The influence of different genetic backgrounds on the tolerance to heavy metals in pine seedlings is also discussed.

Preparation of Aqueous Dispersions of TEMPO-Oxidized Cellulose Nanofibrils with Various Metal Counterions and Their Super Deodorant Performances.

2,2,6,6-Tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofibrils (TOCNs) with sodium carboxylate groups (TOCN-Na) were nanodispersed in water. The Na+ ions of TOCN-Na were exchanged with other monovalent, divalent, and trivalent metal (M) ions. When an aqueous metal acetate or AlCl3 solution was added to a 0.1% TOCN-Na/water dispersion or TOCN-COOH gel/water mixture under suitable conditions followed by sonication in water, individually nanodispersed TOCNs-M with divalent and trivalent metal counterions were obtained in yields of 24-87%. The amount of metal introduced into TOCN-M was approximately 20-50% of the TOCN carboxylate content when divalent and trivalent metal ions were used. These results indicate that intrafibrillar ionic linkages are selectively formed and these TOCN-M species nanodisperse at the individual nanofiber level without agglomeration in water. Filter papers with adsorbed TOCN-Cu/water and TOCN-Ag/water dispersions efficiently decomposed or adsorbed H2S and CH3SH gases, but filter papers containing fibrous TEMPO-oxidized celluloses with Ag+ or Cu2+ counterions had much lower gas-decomposition efficiencies.

Treatment of fluoride in well-water in Khanhhoa, Vietnam by aluminum hydroxide coated rice husk ash

Abstract In this study, aluminum hydroxide coated rice husk ash [RHA/Al(OH)3] was synthesized and used for adsorption of fluoride from aqueous solution. The amorphous material containing 20% (w/w) of Al2O3 was obtained by stirring the mixture of RHA burned at 700°C for 60 min and 0.1 m AlCl3 solution for 30 min. This material possessed porous ordered structure with uniform particle size in the range of 50–100 nm and Brunauer-Emmett-Teller (BET)-specific surface area of 81 m2 g−1. The isotherm data were fitted well to Langmuir model, and the maximum monolayer adsorption capacity was found to be 8.2 mg g−1 at 25°C. The kinetic results revealed that the pseudo-second-order rate model fitted the experiments data better than the pseudo-first-order one and demonstrated the chemical nature of the adsorption of fluoride. Thermodynamic parameters in the temperature range 30–70°C showed that the adsorption was a spontaneous and an endothermic process. RHA/Al(OH)3 can be used for well treatment of fluoride in contaminated well-water in the Ninhhoa district (Khanhhoa province). With the initial fluoride concentration (10.1 mg l−1) and the 2 h of treatment process with the dose of 4.0–7.0 g l−1, the content of fluoride decreased to 0.5–1.5 mg l−1, which met the acceptable limit of WHO.

Cephradine Intercalated Mg-Al Layered Double Hydroxide

Engineered advanced functional materials are promising candidates for biotechnology and biomedical science. Mg-Al layered double hydroxide (LDH), anionic or hydrotalcite-like clays consist of positively charged layers and exchangeable anions along with water molecules in the interlayer space were synthesized from homogeneous solution of MgCl2 and AlCl3 by urea induced co-precipitation method. A pharmaceutically important drug, cephradine was intercalated with synthesized LDH in alkali media (pH 10) by in-situ technique. Characterizations of the products were carried out using Attenuated Total Reflectance Infra-red (ATR-IR), Energy Dispersive X-ray (EDX) and X-ray Diffraction (XRD) spectroscopy. Scanning electron morphological images envisaged a distinct crystalline and amorphous phases of Mg-Al LDH before and after modification with cephradine. Intercalation of bioactive molecules with LDH would enhance their stability providing sustained release behavior in physiological environment.

Mechanisms of Phosphorus Removal by Modified Zeolites Substrates Coated with Zn-LDHs in Laboratory-scale Vertical-flow Constructed Wetlands

Zn-Layered double hydroxides (LDHs) were selected to carry out the experiment in present work based on the previous research results. According to the co-precipitation method, three kinds of different Zn-LDHs (FeZn-LDHs, CoZn-LDHs and AlZn-LDHs) were synthesized by ZnCl2, FeCl3, AlCl3, and CoCl3 solution in alkaline conditions and Zn-LDHs were in-situ coated on the surface of natural zeolites. With the filling of the natural and three kinds of Zn-LDHs modified zeolites in the columns, test experiments were conducted to study the removal performance of phosphorus in vertical-flow constructed wetlands. The results showed that: compared with the natural zeolites, the removal rates of phosphorus by the three kinds of Zn-modified zeolites were greatly improved, especially for FeZn-LDHs. Moreover, the maximum adsorption capacity and the desorbed performance of phosphate were enhanced by the Zn-LDHs coated modification. The adsorption type of phosphate was converted from physical adsorption to chemical adsorption. Through reasonable selection of the type of zeolite and the method of modification, Zn-LDHs modified zeolites could be used to enhance the removal of nitrogen and phosphorus for the eutrophic water.

Solution doped preform with improved uniformity and concentration using dual-layer soot deposition

Abstract A new method of soot deposition to improve the characteristics of a solution-doped optical fibre preform is reported. The soot was generated using a modified chemical vapour deposition (MCVD) technique. A better longitudinal uniformity of the core refractive index profile and a higher degree of dopant incorporation were obtained when two layers of soot were deposited in the core. These improvements were further extended by depositing each layer at different temperatures. A variation of 0.15 × 10−2 (%RSD 3.5%) in the refractive index difference along 23 cm of the preform and a core-to-cladding refractive index difference of approximately 0.012 were achieved using a 1.2 M AlCl3 solution.

Determination of aluminum induced programmed cell death characterized by DNA fragmentation in Gramineae species

Aluminum (Al) toxicity is one of the major abiotic stress factors that decreases crop yield in acidic soils. Al inhibits the root growth and development due to cellular toxicity including nucleus, chromosome and DNA alterations. Although some Al-induced programmed cell death (PCD) features were identified, there are limited comparative and time-dependent studies. The aim of this study is to compare the Al-induced time-dependent DNA fragmentation, the most widely evaluated criterion for PCD in six agronomic plant (maize, wheat, triticale, rye, barley and oat) roots concerning their Al tolerance. Roots were exposed to 100 μM AlCl3 solution (pH 4.5) for different times (½, 1, 2, 3, 4, 5, 6, 7, 8 h). All genomic DNA was isolated from control and AlCl3 treated roots. Isolated DNA samples were analyzed by electrophoretically and DNA fragmentation was observed in triticale, rye, barley and oat roots, but not in maize and wheat. The obtained DNA fragmentation shows that wheat and maize are more tolerant than triticale, rye, barley and oat in which the PCD is active as early as ½ h after Al induction. The results obtained can provide a better understanding into the Al induced PCD and Al tolerance in plants.

Effect of Al doping on the structural and optical properties of electrodeposited SnS thin films

Al‐doped SnS thin films with different Al concentrations were deposited on fluorine doped tin oxide (FTO) substrate from aqueous solution containing 2 mM SnCl2 and 20 mM Na2S2O3 and various amounts of 5 mM AlCl3 solution. The pH, temperature, time, and deposition potential (E) of the solution were kept at 2.1, 60 °C, 30 min and −1 V, respectively. The deposited films were characterized by X‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM), photoluminescence (PL), and UV‐Vis. XRD patterns obviously indicated that the synthesized Al‐doped SnS were polycrystalline with orthorhombic structure and by increasing the amount of Al concentration, the crystallinity was increased. The FESEM images showed that the morphology of the nanostructures was changed with increasing Al content. PL and UV‐Vis analysis were used to investigate the optical properties of materials. The PL spectra showed a red shift with increasing of Al concentration.

Structural Characterization of Aluminum (Oxy)hydroxide Films at the Muscovite (001)–Water Interface

The formation of Al (oxy)hydroxide on the basal surface of muscovite mica was investigated to understand how the structure of the substrate controls the nucleation and growth of secondary phases. Atomic force microscopy images showed that solid phases nucleated on the surface initially as two-dimensional islands that were ≤10 Å in height and ≤200 Å in diameter after 16-50 h of reaction in a 100 μM AlCl3 solution at pH 4.2 at room temperature. High-resolution X-ray reflectivity data indicated that these islands were gibbsite layers whose basic unit is composed of a plane of Al ions octahedrally coordinated to oxygen or hydroxyl groups. The formation of gibbsite layers is likely favored because of the structural similarity between its basal plane and the underlying mica surface. After 700-2000 h of reaction, a thicker and continuous film had formed on top of the initial gibbsite layers. X-ray diffraction data showed that this film was composed of diaspore that grew predominantly with its [040] and [140] crystallographic directions oriented along the muscovite [001] direction. These results show the structural characteristics of the muscovite (001) and Al (oxy)hydroxide film interface where presumed epitaxy had facilitated nucleation of metastable gibbsite layers which acted as a structural anchor for the subsequent growth of thermodynamically stable diaspore grown from a mildly acidic and Al-rich solution.

レーザ誘起湿式改質における溶液成分がSUS316L鋼の改質層形成に及ぼす影響

In order to discuss the influence of component of solution on generation of the treated layer by laser-induced wet treatment, the test pieces of SUS316L were soaked in several solutions, which had acidity or alkalinity, were irradiated by laser. The active solution; Al(NO3)3 and AlCl3 solution generated the treated layer of Fe2+Al2O4. The treated layer generated in Al(NO3)3 solution was thinker than that in AlCl3 solution. On the other hand, the treated layer generated in NaAlO2 solution, which was alkali, was composed of Fe2+Fe2O4. This implies that pH of the solution influenced on the generation of the treated layer.

THE EFFECT OF THE ALUMINUM CHLORIDE--QUERCETIN COMPLEX ON Ca2+, Mg(2+)-ATPase ACTIVITY AND CONTRACTION DYNAMIC PROPERTIES OF MUSCLE TIBIALIS ANTERIOR FROM RANA TEMPORARIA.

Combined effect of aluminum chloride and quercetin solutions on the enzymatic activity and contraction dynamics of muscle fiber bundles of the Rana temporaria m. tibialis anterior was investigated. It was shown that these complexes inhibit muscle contraction. Linear reduction of Ca2+, Mg(2+)-ATPase activity induced by all of the used concentrations of AlCl3 - quercetin was demonstrated. It was found that complex of quercetin with AlCl3 has a greater inhibitory effect on muscle contraction dynamic and causes greater reduction during all periods of stimulation in comparison to the separate effect of the investigated compounds. All the studied concentrations of AlCl3 and quercetin solutions (AlCl3: 10(-4)-10(-2) M; quercetin: 10(-6)-10(-5) M) caused concentration depended contraction strengths and lengths reduction. The decrease in strength and length of muscle contractions was of constant and mostly linear nature within observed timeframe as well as within each periods of contraction. The changes were least pronounced within pretetanic period, but were profound within terminal period of muscle activity. The changes in dynamic contraction properties and Ca2+, Mg(2+)-ATPase activity of sarcoplasmic reticulum under effect of the investigated compounds was minimal in the beginning of the muscle's response to stimulus, prior to muscle strength reaching stable contraction level.

Water-resistant and high oxygen-barrier nanocellulose films with interfibrillar cross-linkages formed through multivalent metal ions

Once-dried 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofibril (TOCN) films with sodium carboxylate groups (TOCN–COONa) were soaked in aqueous MgCl2, CaCl2, AlCl3 and FeCl3 solutions to change the counterion to TOCNs–COOM films (M: metal ion). Dry TOCN–COOM films had high Young's moduli (11–20GPa) and tensile strength (170–280MPa). In particular, the wet TOCN films with aluminum and iron (III) carboxylates had high Young's moduli and tensile strengths of ~3GPa and 30–40MPa, respectively, even at water contents of ~470%. Moreover, the dry TOCN films with calcium and aluminum carboxylates had extremely low oxygen permeabilities of 0.08 and 0.15mLµmm−2day−1kPa−1, respectively, even at 80% relative humidity, which are outstanding values compared to those of other films reported previously. These results are explained in terms of the high water resistance of the films, which is caused by the formation of interfibrillar cross-linkages through multivalent metal ions.

ALUMINUM CHLORIDE EFFECT ON Ca2+,Mg(2+)-ATPase ACTIVITY AND DYNAMIC PARAMETERS OF SKELETAL MUSCLE CONTRACTION.

We studied enzymatic activity and measured strain-gauge contraction properties of the frog Rana temporaria m. tibialis anterior muscle fascicles during the action of aluminum chloride solution. It was shown that AlCl3 solutions did not affect the dynamic properties of skeletal muscle preparation in concentrations less than 10(-4) M Increasing the concentration of AlCl3 to 10(-2) M induce complete inhibition of muscle contraction. A linear correlation between decrease in Ca2+,Mg(2+)-ATPase activity of sarcoplasmic reticulum and the investigated concentrations range of aluminum chloride was observed. The reduction in the dynamic contraction performance and the decrease Ca2+,Mg(2+)-ATPase activity of the sarcoplasmic reticulum under the effect of the investigated AlCl3 solution were minimal in pre-tetanus period of contraction.

Effect of aluminum hydrolyte species on human enterovirus removal from water during the coagulation process

We prepared different types of aluminum-based coagulants, consisting of mainly monomeric aluminum species, polymeric aluminum species, or colloidal aluminum species, to investigate the effect of aluminum hydrolyte species on the removal of two types of human enteroviruses, poliovirus (PV) type 1 and the free-chlorine-resistant virus coxsackievirus (CV) B5, from lake and river water samples during the coagulation process. We found that differences in the distribution of the aluminum hydrolyte species in the coagulant affected the removal of these enteroviruses during coagulation: the removal ratios of PV and CV observed with polyaluminum chloride (PACl) with a high colloidal aluminum content and a basicity of 2.1 (i.e., PACl-2.1c) were larger than those observed with high monomeric aluminum content coagulant (i.e., AlCl3 solution) and with high polymeric aluminum content coagulant PACl (PACl-2.1b). Unlike AlCl3 or PACl-2.1b, PACl-2.1c contains Al30 species, indicating that Al30 species probably play a major role in the removal of enteroviruses. The PV and CV removal ratios were almost identical, regardless of the coagulant type or viral quantification method used (plaque-forming unit method or real-time polymerase chain reaction method), suggesting that PV and CV behaved similarly during the coagulation process. We also experimentally confirmed that the main mechanism for virus removal was coprecipitation into growing aluminum hydroxide during charge neutralization; virus adsorption onto formed aluminum hydroxide flocs also contributed to virus removal, but played a limited role.

ChemInform Abstract: Isolation and Characterization of the [Ga2Al18O8(OH)36 (H2O)12]8+ Cluster: Cationic Variations on the Wells—Dawson Topology.

AbstractA new heterometallic cluster, [Ga2Al18O8(OH)36 (H2O)12](nds)4·31H2O (nds: 2,7‐naphthalene disulfonate) is synthesized by heating a partially hydrolized aqueous solution of AlCl3 and GaCl3 with a Ga/Al ratio of 1:2 at 80 °C for 24 h in an autoclave followed by addition of Na2(nds) as a co‐crystallization agent (room temperature, 21 d, 30% yield).

Preparation and characterization of aluminum oxide coated extracted silica from rice husk ash for monoglyceride removal in crude biodiesel production

In this study, aluminum oxide was coated on extracted silica from rice husks (AO_RHA). First, the silica was produced by heating the rice husk at 700 °C for 6 h following precipitation using NaOH and H2SO4 (RHA). The coating process was carried out using AlCl3 solution. The effect of stirring times, pH, and calcination conditions were investigated. The characterization of AO_RHA was performed using BET, XRD, FTIR, and ICP techniques. This study demonstrated the influence of the AO_RHA structure on monoglyceride removal. Langmuir and Freundlich adsorption isotherms were used to model the equilibrium isotherms and determine the isotherm constants. The adsorption capacity increased after the excess methanol was removed. In addition, the spent AO_RHA was regenerated and can be efficiently reused up to four times.

Effects of Na, Ca, Mg, and Al Chloride Salts on Dissolution and Phase Stability of Calcium Sulfate Dihydrate in Aqueous Solutions at 278.15 K to 308.15 K

Dissolution trend and solubility data of calcium sulfate dihydrate (CaSO4·2H2O gypsum) in aqueous Na, Ca, Mg, and Al chloride salt solutions have been studied at 278.15 K to 308.15 K. The concentration ranges were up to 4.5 mol·L–1 for NaCl, 3.0 mol·L–1 for MgCl2, 2.0 mol·L–1 for CaCl2, and 1.6 mol·L–1 for AlCl3, respectively. Measurement results show that except for CaCl2, the other three salts allow the solubility of gypsum to rise a lot first and then descend smoothly after attaining the maximum. Because of common ions effect, the solubility of CaSO4·2H2O drops sharply in CaCl2 solution at low concentration and continues to fall almost linearly as concentration exceeds 0.2 mol•kg–1. Impacts of Na, Mg, Al chloride salts on solubility of CaSO4·2H2O are explained on the basis of dissolution and thermodynamic equilibrium. The solubility of CaSO4·2H2O in AlCl3 solution is highest compared with that in NaCl and MgCl2 solution because two sulfur-bearing chemical complex Al(SO4)2–(aq) and AlSO4+(aq) are expect...