Colloidal Aluminum Hydroxide Research Articles

Synthesis of alumina ceramic encapsulation for self-healing materials on thermal barrier coating

Durability of Thermal Barrier Coating or TBC can be optimized by inducing Self-Healing capabilities with intermetallic materials MoSi2. Nevertheless, high temperature operation causes the self-healing materials to become oxidized and lose its healing capabilities. Therefore, a method to introduce ceramic encapsulation for MoSi2 is needed to protect it from early oxidation. The encapsulation process is synthesized through a simple precipitation method with colloidal aluminum hydroxide as precursor and variations on calcination process. Semi-quantitative analysis on the synthesized sample is done by using X-ray diffraction (XRD) method. Meanwhile, qualitative analysis on the morphology of the encapsulation was carried out by using Scanning Electron Microscope (SEM) and Field Emission Scanning Electron Microscope (FESEM) equipped with dual Focus Ion Beam (FIB). The result of the experiment shows that calcination process significantly affects the final characteristic of encapsulation. The optimum encapsulation process was synthesized by colloidal aluminum hydroxide as a precursor, with a double step calcination process in low pressure until 900 °C.

Recycled Alumina Production from the Anodizing Industry to Tubulation Coating of Petroleum Craking

The anodizing of aluminum is a common technique used to produce decorative and protective high quality film. This process results in significant volume of industrial sludge containing considerable amounts of colloidal aluminum hydroxide, which is a problem in the disposal of these industrial wastes due to the environmental impact. This paper aims at the treatment of theses residues, which were heat-treated at the temperatures of 200°C, 1000°C and 1400°C. After each treatment, the residues were put to the X-Ray Difraction and the X-ray Fluorescence analysis. In evaluating these results, it was found a gradual increase of the percentage of alumina at 1400°C to achieve 93%. With the acquisition of ceramic mass with a high content of alumina, the objective being to make a refractory to coat the petroleum refining pipes, thereby solving an environmental problem from the aluminum industry, presenting an alternative to the petroleum industry. These residues were compacted and immersed in land and sea petroleum for 30 days, after this period its mechanical properties were analyzed to study its response to the contact with the petroleum, where it was found that these remained kept.

Effect of fresh aluminum hydroxide gels on algae removal from micro-polluted water by polyaluminum chloride coagulant

Polyaluminum chloride (PAC) coagulant, a most commonly used inorganic coagulant, was prepared using fresh aluminum hydroxide gels under the low energy consumption. The aim of this study was to investigate the influence of fresh aluminum hydroxide gels on the characteristics of PAC and the algae removal from micro-polluted water. The results suggested that PAC with the basicity values (OH/Al) of 2.5 and 2.0 synthesized by this method possessed the high content of middle polymeric aluminum (Alb2). And fresh aluminum hydroxide gels contributed to the formation of Alb2. Adding fresh aluminum hydroxide gels in the aging period temporarily increased the small/middle polymeric aluminum (Alb) content that rapidly reduced with the time extending since fresh aluminum hydroxide gels accelerated the aluminum hydrolysis. The excessive fresh aluminum hydroxide gels would aggravate the decrease of Alb content. The presence of fresh aluminum hydroxide gels in PAC slightly reduced the coagulation efficiency, but the performance deterioration resulted from overdosing was weakened in the cases. Besides, the residual aluminum concentrations in the treated water were always low as fresh aluminum hydroxide gels induced the generation of colloidal aluminum hydroxide particles. Charge neutralization was not the only coagulation mechanism in this treatment.

Stabilization of a recombinant ricin toxin A subunit vaccine through lyophilization

Lyophilization was used to prepare dry, glassy solid vaccine formulations of recombinant ricin toxin A-chain containing suspensions of colloidal aluminum hydroxide adjuvant. Four lyophilized formulations were prepared by using combinations of rapid or slow cooling during lyophilization and one of two buffers, histidine or ammonium acetate. Trehalose was used as the stabilizing excipient. Aggregation of the colloidal aluminum hydroxide suspension was reduced in formulations processed with a rapid cooling rate. Aluminum hydroxide particle size distributions, glass transition temperatures, water contents, and immunogenicities of lyophilized vaccines were independent of incubation time at 40°C for up to 15weeks. Mice immunized with reconstituted ricin toxin subunit A (RTA) vaccines produced RTA-specific antibodies and toxin-neutralizing antibodies (TNAs) regardless of the length of high temperature vaccine storage or the degree of aluminum adjuvant aggregation that occurred during lyophilization. In murine studies, lyophilized formulations of vaccines conferred protection against exposure to lethal doses of ricin, even after the lyophilized formulations had been stored at 40°C for 4weeks. A corresponding liquid formulation of vaccine stored at 40°C elicited RTA-specific antibody titers but failed to confer immunity during a ricin challenge.

Structural perturbation of diphtheria toxoid upon adsorption to aluminium hydroxide adjuvant

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 particles based on a high adsorption degree, adsorption rate and adsorptive capacity. The conformation and stability of diphtheria toxoid in solution and adsorbed to aluminium hydroxide adjuvant were characterized using five physicochemical techniques: intrinsic and extrinsic fluorescence spectroscopy, circular dichroism, infrared spectroscopy and differential scanning calorimetry. Diphtheria toxoid adsorbed to aluminium hydroxide resulted in a minimal shift of the tryptophan fluorescence spectrum, whereas a large increase in the emission of the Bis-ANS probe was observed, indicating that hydrophobic sites of the protein became accessible due to adsorption. In addition, circular dichroism and infrared spectroscopy revealed that adsorption to aluminium hydroxide caused an increase of β-sheet content and a decrease of α-helix content in diphtheria toxoid. Differential scanning calorimetry demonstrated a major decrease in the enthalpy of denaturation upon adsorption. In conclusion, the adsorption of diphtheria toxoid to aluminium hydroxide adjuvant leads to substantial conformational changes in the antigen. Since physicochemical methods can be used to monitor these conformational changes, these analytical methods might offer a tool in regulatory required vaccine quality control by demonstrating consistency in production.

Adsorption properties of alumina-aluminum cermets prepared in the aluminum powder reaction with water in the presence of surfactants

By a method of low-temperature nitrogen adsorption-desorption at the gas/solid interface, the trends in the adsorption and capillary-condensation properties of Al2O3/Al composites are studied as a function of the way of conjugate stages, namely, the metal hydrothermal oxidation and the replication of colloidal aluminum hydroxide by surfactants of the anionic, cationic, and non-ionogenic types.

Interactions of aluminium hydrolytic species with biomolecules

In this contribution the formation of bioinorganic assemblies between the basic globular protein lysozyme and aqueous aluminium species including Al13-mer, Al30-mer and colloidal aluminium hydroxide have been explored and comparison made to previous interaction studies performed with bovine serum albumin (BSA). Specific charge-stabilised bioinorganic assemblies involving aluminium species and lysozyme were observed to form in contrast to the gel like structures formed on interaction of BSA with aluminium species. As demonstrated by infrared spectroscopy (structural assignment, 2D correlation spectroscopy), interactions mostly involve acidic surface groups of the proteins (Asp, Glu), with strong complexation and deprotonation in the case of BSA interacting with Al13 and Al30 and through hydrogen bonding for lysozyme interacting with the same species and aluminium hydroxide particles interacting with both biomolecules.

Oligonucleotide containing CpG motifs enhances immune response to mucosally or systemically administered tetanus toxoid

Oligodeoxynucleotides (ODN) containing unmethylated CpG dinucleotides induce proliferation of B cells and activation of macrophages and thus stimulation of the immune system. We tested an oligonucleotide containing an unmethylated CpG dinucleotide flanked by two 5′ purines and two 3′ pyrimidines (GAGAA CG CTCGACCTTCGAT) for the ability to affect antibody levels to tetanus toxoid (Tt). Groups of male Rowett rats ( n=5–6/group) received colloidal aluminium hydroxide (Al(OH) 3) either alone, or with Tt bound to the Al(OH) 3, or with Tt bound to Al(OH) 3 with the addition of the CpG oligonucleotide. Antigens were administered subcutaneously in the salivary gland vicinity once, or by gastric intubation on 3 consecutive days. On day 124 all animals were given a boost with the same material by the same route. Serum IgG and saliva IgA antibody to Tt was determined by ELISA. Serum antibody levels were significantly higher in ODN+Tt treated rats than in Tt-alone rats immunized by either route after primary or booster immunizations. Thus, administration of an ODN containing unmethylated CpG motifs along with an immunogen bound to Al(OH) 3 can result in enhanced specific antibody when administered by intragastric as well as subcutaneous routes.

Particle speciation analysis of inorganic polymer flocculants: an examination by photon correlation spectroscopy

The particle size distribution for two typical kinds of inorganic polymer flocculants is characterized comparatively by using photon correlation spectroscopy (PCS). The experimental results indicate that there exists large difference in particle speciation distribution between PFCl and PACl prepared under similar conditions. The particle size of PFCl samples range in a narrow distribution. Their mean effective hydrodynamic diameters calculated by translational diffusion coefficient are between 5 and 11 nm. For PACl samples at certain basicity, no visible particle species can be determined. At high basicity, both laboratory prepared and commercial products, show a bimodal distribution: one in 2–5 nm and the other ranges in several decades of nm with wide distribution. The latter may be colloidal aluminum hydroxide and also some aggregates of polymers.

Preparation and optical properties of spherical colloidal aluminum hydroxide particles containing a dye

Colored colloidal spherical particles of aluminum hydroxide were prepared by aging aluminum sulfate solutions containing a chelating dye (3 Mordent Blue). The dye was incorporated in the particles and could not be removed by washing. The surface charge and the optical properties of this system were investigated.

The Adsorbing Colloid Flotation of Fluoride Ion by Aluminum Hydroxide in Aqueous Media

Abstract Up to 15.7 ppm fluoride can be removed from solution, pH 7.3 to 7.8, by adsorption onto colloidal aluminum hydroxide at a concentration of 40 ppm Al. This adsorbing colloid-adsorbed ion combination is then removed by foaming with 40 ppm sodium lauryl sulfate. After 30 min the concentration of fluoride is 0.0 ppm. The concentration of aluminum is also 0 ppm. Efficiency of removal slowly decreases with increasing ionic strength. Chloride ion interference is minimal.

Electrokinetic Behavior of Aluminum Species in Dilute Dispersed Kaolinite Systems

The objective of this study was to examine the specific behavior of the different aluminum ion species including hydrated trivalent aluminum ion, hydrolyzed polymeric multivalent aluminum ions, and colloidal aluminum hydroxide in aluminum‐kaolinite interactions with the subsequent destabilization of a dispersed system of negatively charged clay particles. The major experimental work investigated the various destabilization phenomena at three arbitrarily chosen final pH values: pH 3, pH 5, and pH 8. Microelectrophoretic techniques were used throughout this study in order to reveal any significant differences in the electrokinetic properties of the flocs which might be attributed to specific hydrolysis products, and also to elucidate the charge reversal phenomena due to the specific adsorption of the polymeric multivalent aluminum ions.

Field trials with Bordeaux mixture and various formulations of copper oxychloride for control of late blight of potatoes and black pod of cacao

Results of field trials for the control of potato blight ( Phytophthora infestans ) in the United Kingdom, and of black pod disease of cacao ( Phytophthora palmivora ) in West Africa, have yielded information on the mode of action of Bordeaux mixture. The experiments were designed to compare the disease-controlling properties of Bordeaux mixture with those of a copper oxychloride wettable powder (WP) and of a copper oxychloride suspension supplemented by colloidal aluminium hydroxide. The latter adjuvant was chosen as a result of earlier laboratory studies. The following conclusions are drawn from the data, (1) Bordeaux mixture does not always give better disease control than a copper oxychloride WP suspension of equal copper content. (2) Copper oxychloride suspensions supplemented by the appropriate concentrations of aluminium hydroxide gave results almost identical with those of Bordeaux mixture both against P. infestans and P. palmivora . (3) The superiority of Bordeaux mixture and the supplemented oxychloride over oxychloride WP is attributed primarily to the physical characters of these spray liquids; more particularly to the fact that both Bordeaux and the aluminium hydroxide supplement are irreversible, deformable hydrogels. (4) The particle size of all copper oxychloride samples used in these experiments was considerably greater than that of the active ingredient of Bordeaux mixture. It has been shown in the field, however, that the reduced toxicity often associated with greater particle size can be offset by a suitable alteration in the physical characteristics of the fungicide suspension.

Mechanism of differential staining of nucleic acids.

WORK in this Department, to be published elsewhere, has shown that several histological methods for the demonstration of mucin depend for their selectivity on the use of cations of large size. Thus alcian blue, with a molecular weight of about 1,341 (ref. 1), is almost specific for acid mucins, being apparently unable to enter other, more dense, basophilic structures. The dialysed iron method2 similarly depends on the use of large particles (colloidal ferric hydroxide), while in Southgate's mucicarmine the small carmine molecule is probably adsorbed on to colloidal aluminium hydroxide.

The capacity of aluminum to prevent prothrombin depression by quartz: An experimental study on guinea pigs

Summary When 40-mg doses of 1–3 μ quartz particles in a 4-ml normal saline were injected intracardially in each of fifteen guinea pigs, normal blood clotting was prevented for several hours. Eleven animals died from “silica shock.” Colloidal aluminum hydroxide, particulate oxidized metallic aluminum, and precipitated aluminum hydrate similarly administered have no significant effect on blood globulins. On injection of the aluminum agents in various doses simultaneously with the quartz, prothrombin depression is inhibited by the colloidal aluminum hydroxide and by aluminum hydrate, but not by particulate metallic aluminum. Dissolved silica Si(OH) 4 has no effect on blood clotting, and the supernatant fluid from a suspended mixture of quartz and aluminum hydrate proved to be equally inert. All the guinea pigs which had received the quartz plus aluminum hydrate or quartz plus metallic particulate aluminum died; thus colloidal aluminum hydroxide remains as the only safe intravascularly administered antidote against silica. The prothrombin depression is due to the protein-denaturing action of forces at the surface of quartz particles. These forces are nullified by adsorbed colloidal aluminum hydroxide.

Electron microscope studies on the aging of amorphous colloidal aluminium hydroxide

This paper describes the electron microscope morphology of gels of aluminium hydroxide and of aluminium oxide monohydrate Bohmite and the transformations which occur at room temperature during the aging of C-alpha gel prepared from ammonium alum. A mechanism for the morphological transformations during the aging of C-alpha gel and for the formation of somatoids is suggested.

Some factors influencing the roentgen visualization of the mucosal pattern of the gastromestinal tract.

Historical Review (1, 2a) Within the years immediately following the discovery of x-rays, the possibility of visualizing the stomach and intestines by the use of radiopaque media had been realized and explored. Since the introduction of barium sulfate, it has remained the single important intestinal contrast material. The earliest observations concerned the movements and motility of the gastrointestinal tract, mostly in animals, with little attention to morphological detail. In man, because of inability to obtain satisfactory radiographs, the study of disease became one of “symptom-complexes,” wherein the mobility, shape, and peristaltic activity of the stomach and intestines, observed fluoroscopically, determined the diagnosis. Toward the end of the first decade of the present century, with improvement in design of transformers and the introduction of fluorescent screens, the radiopaque filled viscus could be filmed, with demonstration of its outline and of the larger defects. Shortly after this, the importance of visualizing the mucosal folds was realized, and the sedimentation method was introduced. Following ingestion of a thin bismuth solution, the patient remained in a supine or prone position for twenty minutes, after which a film was exposed. Soon afterward it was found that, with the use of a small amount of medium carefully distributed over the gastric wall by positioning, the entire mucosal pattern could be outlined. In 1921, Akerlund (3) introduced his thin-layer compression technic for the demonstration of duodenal cap lesions. Pressure correctly applied displaced all excess medium and left only the mucosal outline and any associated defects. This method was adapted for the visualization of the mucous membrane of the stomach during fluoroscopy. Repeated attempts have been made to improve the quality of the pattern by using different media or adjuvants to the standard media. Among these are buttermilk, tragacanth, acacia, honey, and more recently mucin (4), oil (5), gelatine (6), saline (7), and colloidal aluminum hydroxide (8). During the past decade, attention has been directed to the particle size of the medium itself, and several investigators (2b, 8–11) have claimed to have obtained improved mucosal studies with the use of barium sulfate of small particle size. To our knowledge, there have been no detailed investigations relating the state of individual resting gastric function, such as pH, mucin production, and motility, to the mucosal pattern as obtained on films or at fluoroscopy, nor has there been any correlation between the type of stomach (asthenic, hypersthenic, etc.) and the excellence of mucosal detail obtained. Experimental Procedures and Results The materials used in the present studies were as follows:2 1. Barium sulfate, U.S.P. 2. Barium sulfate micropowder, 3. linckrodt 4. Barium sulfate, 1.05 μ.

Electron microscope studies on the aging of amorphous colloidal aluminium hydroxide

Electron microscope studies on the aging of amorphous colloidal aluminium hydroxide

Peptic ulcer: medical cure by efficient gastric acid neutralization.

Article1 January 1952PEPTIC ULCER: MEDICAL CURE BY EFFICIENT GASTRIC ACID NEUTRALIZATIONN. E. ROSSETT, M.D., F.A.C.P., F. H. KNOX JR., M.D., S. L. STEPHENSON JR., M.D.N. E. ROSSETT, M.D., F.A.C.P.Search for more papers by this author, F. H. KNOX JR., M.D.Search for more papers by this author, S. L. STEPHENSON JR., M.D.Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-36-1-98 SectionsAboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail ExcerptINTRODUCTIONIn two communicationsl1, 2evaluating a number of commonly used antacids utilizing a continuous pH recorder in vivo and in vitro, Rossett and Flexner concluded that magnesium oxide, peroxide, hydroxide and carbonate, as well as calcium carbonate, when combined with an amphoteric substance such as milk or aluminum hydroxide gel, were efficiently buffered in their alkaline range preventing rebound and produced long-acting antacids. A promise of clinical evaluation of such antacids made at that time could not be effectively fulfilled because of World War II service and until the senior author had the opportunity of supervising a large gastrointestinal...Bibliography1. RossettFlexner NEJ: A method for the continuous recording of gastric pH in situ. IV. Further evaluation of the efficacy of antacids in vitro and in the human being, Ann. Int. Med. 18: 193, 1943. LinkGoogle Scholar2. RossettFlexner NEJ: The effect of certain antacids in man as measured by a simplified method for the continuous recording of gastric pH, Ann. Int. Med. 21: 119, 1944. LinkGoogle Scholar3. Sippy BW: Gastric and duodenal ulcer: medical cure by an efficient removal of gastric juice corrosion, J. A. M. A. 64: 1625, 1915. CrossrefGoogle Scholar4. RubinBowmanMoses SKML: Electroencephalographs and personality correlates in peptic ulcer, Psychosom. Med. 4: 309, 1942. CrossrefGoogle Scholar5. Moses L: Psychodynamic and electroencephalographic factors in duodenal ulcer, Psychosom. Med. 8: 405, 1946. CrossrefMedlineGoogle Scholar6. Alexander F: A case of peptic ulcer and personality disorder, Psychosom. Med. 9: 320, 1947. CrossrefMedlineGoogle Scholar7. Zane MD: Psychosomatic considerations in peptic ulcer, Psychosom. Med. 9: 372, 1947. CrossrefMedlineGoogle Scholar8. Saul LJ: Psychiatric treatment of peptic ulcer patients, Psychosom. Med. 8: 204, 1946. CrossrefMedlineGoogle Scholar9. Dragstedt LR: Section of the vagus nerves to the stomach in the treatment of gastroduodenal ulcer, Minnesota Med. 29: 597, 1946. MedlineGoogle Scholar10. Dragstedt LR: Section of the vagus nerves to the stomach in the treatment of peptic ulcer, Surg., Gynec. and Obst. 83: 547, 1946. MedlineGoogle Scholar11. Alvarez WC: Sixty years of vagotomy; a review of some 200 articles, Gastroenterology 10: 413, 1948. MedlineGoogle Scholar12. KirsnerPalmer JBWL: Alkalosis complicating the Sippy treatment of peptic ulcer, Arch. Int. Med. 69: 791, 1942. CrossrefGoogle Scholar13. KretschmerBrown HLRC: Do alkalies used in the treatment of peptic ulcer cause kidney stones? J. A. M. A. 113: 1471, 1939. CrossrefGoogle Scholar14. BowersRossett RFNE: Bleeding peptic ulcer: favorable results of conservative therapy, Ann. Surg. 132: 690, 1950. CrossrefMedlineGoogle Scholar15. CumminsGrossmanIvy GMMLAC: A study of the time of "healing" of peptic ulcer in a series of sixty-nine cases of duodenal and gastric craters, Gastroenterology 7: 20, 1946. MedlineGoogle Scholar16. Havens WP: Intestinal obstruction caused by colloidal aluminum hydroxide, J. A. M. A. 113: 1564, 1939. Google Scholar17. Meulengracht E: Fifteen years of experience with the free feeding of patients with bleeding peptic ulcer, Arch. Int. Med. 80: 697, 1947. CrossrefGoogle Scholar18. LevinKirsnerPalmerButler EJBWLC: The fasting nocturnal gastric secretion in normal individuals and in patients with duodenal ulcer, gastric ulcer and gastric carcinoma, Arch. Surg. 56: 345, 1948. CrossrefMedlineGoogle Scholar This content is PDF only. To continue reading please click on the PDF icon. Author, Article, and Disclosure InformationAffiliations: *Received for publication November 6, 1950.From the Gastroenterology Section of the Medical Service, Veterans Administration Medical Teaching Group, Kennedy Hospital, Memphis, Tennessee.Reviewed in the Veterans Administration and published with the approval of the Chief Medical Director. The statements and conclusions published by the authors are the result of their own study and do not necessarily reflect the opinion or policy of the Veterans Administration. PreviousarticleNextarticle Advertisement FiguresReferencesRelatedDetails Metrics Cited byHYPERCHLORHYDRIA, DUODENITIS AND DUODENAL ULCER: A CLINICAL STUDY OF THEIR INTERRELATIONSHIPS*J. DONALD OSTROW, M.D., ROBERT H. RESNICK, M.D.USE AND ABUSE OF ANTICHOLINERGIC DRUGS IN THE MANAGEMENT OF GASTROINTESTINAL DISEASE*ALVIN J. CUMMINS, M.D.The Adverse Effects of Belladonna Alkaloids in Benign Pyloric ObstructionTreatment of Peptic Ulcer 1 January 1952Volume 36, Issue 1Page: 98-109KeywordsCalciumCarbonatesGastric ulcersMagnesiumMedical servicesMilkMouthPeptic ulcersVision Issue Published: 1 January 1952 PDF downloadLoading ...

Rapporti tra costituzione della protrombina e ipoprotrombinemie

After referring to the constitution of prothrombin as it is generally accepted to-day (A-factor, B-factor, labile factor) the author describes procedures according to which it is possible to distinguish the forms of hypoprothrombinaemia resulting from the lack of A- and B-factor respectively:- in the former are included the cases of dicumarol intoxication and those with plasma treated with colloidal aluminium hydroxide, in the latter those of K-avitaminosis (icterus with or without hepatic insufficience). In this last condition it can be shown that the sera act differently from the normal, which probably is to be referred to a lack of A-factor.