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Publication Metadata only Delayed sequelae of hydrochloric acid ingestion(1999-06-01) Chumpon Wilasrusmee; Vorachai Sirikulchayanonta; Wiwat Tirapanitch; Mahidol UniversityHydrochloric acid is the active ingredient in common toilet bowl cleaner agents used in Thailand but it is occasionally abused for suicidal attempts by ingestion. Clinicopathological description caused by this agent has rarely been mentioned... and no postoperative complication was found. This presentation is aimed to stimulate physicians to be aware of delayed complications of hydrochloric acid ingestion and long term follow-up is required even though the initial symptoms of the patients were minimal.Publication Metadata only Tryptamine as a corrosion inhibitor of mild steel in hydrochloric acid solution(2010-01-01) Pongsak Lowmunkhong; Dusit Ungthararak; Pakawadee Sutthivaiyakit; Mahidol UniversityThe inhibitor effect of tryptamine on the corrosion of mild steel in 0.5 M hydrochloric acid at 30 °C was investigated using linear polarization, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniquesPublication Metadata only Titanium and iron dissolutions from ilmenite by acid leaching and microbiological oxidation techniques(2013-05-01) Woranart Jonglertjunya; Theeraporn Rubcumintara; Mahidol UniversityThis research was concerned with the solubility of ilmenite (Tin Tailing) in acids (sulfuric, hydrochloric, oxalic and citric) and bioleaching by Aspergillus niger, Penicillium citrinum and Bacillus megaterium. Ilmenite concentrate was soluble in 1....5 M sulfuric acid and 1.5 M hydrochloric acid solutions at 90 °C. However, improved leaching was obtained with 8 and 12 M sulfuric acid solutions. The chemical leaching results for different stirring speeds showed that a speed of 750 rpm was favourablePublication Metadata only Effect of acid during synthesis on the agglomerated strength of TiO 2 nanoparticles(2009-10-26) Sarayut Termnak; Wannapong Triampo; Darapond Triampo; Mahidol Universityhydrochloric acid was added during the synthesis. With no acid, both anatase and brookite structures were formed. Transmission electron microscopy (TEM) showed that the primary particles from both the acid and no-acid routes were of approximately the same size.... A particle-size analyzer equipped with an ultrasonic generator showed, however, that the aggregates of acid NPs were more difficult to break apart than those of the no-acid NPs. Gel formation was used to explain the difference in strength by whichPublication Metadata only Morphological Properties of Acid-modified Tapioca Starch(2000-09-01) Napaporn Atichokudomchai; Sujin Shobsngob; Saiyavit Varavinit; Mahidol UniversityHighly crystalline tapioca starch was prepared by partial hydrolysis of tapioca starch in hydrochloric acid at room temperature for various lengths of time. The crystallinity of the starch increased while its amylose content decreased... with increasing reaction time. Scanning electron micrographs of these natural and highly crystalline starches were taken in order to study the morphological changes and mode of acid attack during hydrolysis. Exocorrosion all over the surface was observed after 96Publication Metadata only Reactive surface treatment for calcium carbonate filler in polypropylene(1999-01-01) Arunee Tabtiang; Richard Venables; Mahidol Universityacrylate. Direct evidence for transfer grafting between the calcium acrylate and the polypropylene in the reactive coating was obtained through selective dissolution of the matrix phase and filler with hot xylene and dilute hydrochloric acid, respectively...Calcium carbonate has been modified with three surface modifying systems based upon stearic acid, acrylic acid and a reactive coating comprising acrylic acid with dicumyl peroxide through dry blending. Polypropylene homopolymer was compoundedPublication Metadata only Gelatinization transitions of acid-modified tapioca starches by Differential Scanning Calorimetry (DSC)(2002-07-01) Napaporn Atichokudomchai; Saiyavit Varavinit; Pavinee Chinachoti; Mahidol University; University of MassachusettsTapioca starch was partially hydrolyzed by 6% and 12% hydrochloric acid (w/v) at room temperature for various length of time. The gelatinization transitions of the acid-modified tapioca starches were studied using Differential Scanning CalorimetryPublication Metadata only A study of some physicochemical properties of high-crystalline tapioca starch(2001-11-01) Napaporn Atichokudomchai; Sujin Shobsngob; Pavinee Chinachoti; Saiyavit Varavinit; Mahidol University; University of MassachusettsTapioca starch was partially hydrolyzed in hydrochloric acid solution at room temperature for various lengths of time to obtain high-crystalline starches. RVA viscoamylograms of acid-modified starches demonstrated a very low viscosity as compared... to that of native tapioca starch. The relative crystallinity of native and acid-modified tapioca starches were measured by X-ray diffraction ranging from 39.53% to 57.75%. The native and acid-modified tapioca starches were compressed into tablets using variousPublication Metadata only Chemical force mapping of phosphate and carbon on acid-modified tapioca starch surface(2009-01-01) Karntarat Wuttisela; Wannapong Triampo; Darapond Triampo; Mahidol University; Center of Excellence for Vectors and Vector-Borne Diseases; Center of Excellence for Innovation in ChemistrySurface chemical microstructure of hydrochloric acid hydrolyzed tapioca starch producing different amylose:amylopectin (Am:Ap) ratios were studied with scanning chemical force microscopy (CFM). The chemical force probes were functionalized of two... types with -OH (phosphate specific) and -CH3(carbon specific). Lateral force trace-minus-retrace (TMR) images from -OH and -CH3probes revealed changes in the phosphate domains and the carbon backbone for the varying acid hydrolyzed tapioca starchPublication Metadata only A study of annealing and freeze-thaw stability of acid-modified tapioca starches by differential scanning calorimetry (DSC)(2002-08-01) Napaporn Atichokudomchai; Saiyavit Varavinit; Pavinee Chinachoti; Mahidol University; University of MassachusettsTapioca starch was partially hydrolyzed by 6% (w/v) hydrochloric acid at room temperature for various lengths of time. Annealing and freeze-thaw stability of the acid-modified starches were studied using Differential Scanning Calorimetry (DSC...). In the annealing study, as the hydrolysis time increased, the effect of annealing on narrowing and shifting the endothermic peak to a higher temperature was decreased. The endothermic transition of annealed 48-h acid-modified tapioca starch showed a narrow peak