Alfred Antony Christy

• Das, Arnab; Rudra, Souman; Hossain, Md Iftekher; Islam, Anfaj; Das, Opy & Christy, Alfred Antony [Show all 7 contributors for this article] (2025). Feasibility assessment of bioethanol-castor oil blends (CASAHOL) as sustainable marine engine fuel: balancing performance and emissions. Discover Applied Sciences. 7. doi: 10.1007/s42452-025-07757-w. Full text in Research Archive Show summary

  This research investigates the viability of bioethanol (BE)-castor oil (CO) mixtures (CASAHOL) as an alternative fuel for marine engines, specifically targeting a dual-cylinder, four-stroke, naturally aspired (carburetor) engine. The study seeks to reduce the ecological consequences of fossil fuels by exploring renewable fuel alternatives. Four fuel blends with differing bioethanol and castor oil ratios were evaluated to determine their impact on engine performance, emissions, and fuel characteristics. Experimental results indicate that the 96%BE-4%CO blend attains the best thermal efficiency (24.27%) and produces a power output of 10.7 kW at max speed, establishing it as a formidable alternative to conventional fuels. Nonetheless, it generates comparatively elevated CO 2 (10.5% vol) and NOx emissions (1164 ppm at 2000 RPM), signifying a compromise between performance and pollution. Conversely, the 99%BE-1%CO mixture exhibits the lowest NOx emissions (165 ppm at 1000 RPM), although demonstrates inferior thermal efficiency and power production. The research underscores the necessity to refine fuel mixtures to achieve a balance among efficiency, performance, and ecological consequences. The 96% BE-4% CO blend presents a feasible solution, enhancing engine performance while maintaining acceptable emission standards. Additional research is advised to enhance these blends and investigate additions that may diminish the recorded emission levels.

• Prathumsuwan, Thitarat; Kladsomboon, Sumana; Christy, Alfred Antony; In, Insik; Liang, Xiao & Song, Shufeng [Show all 10 contributors for this article] (2024). Integration of jackfruit seed-derived carbon dots and electronic nose for a sensitive detection of formaldehyde vapor. Journal of Metals, Materials and Minerals. 34(1), p. 1–11. doi: 10.55713/jmmm.v34i1.1846. Full text in Research Archive
• Christy, Alfred Antony; Sukumar, Raveena & Munige, Shakya Sankalpani Gunasena Wije (2023). Preparation and Infrared Spectroscopic Studies of Fully Deuterium Oxide Replaced Analogue of Calcium Oxalate Monohydrate. Asian Journal of Chemistry. ISSN 0970-7077. 35(4), p. 1014–1018. doi: 10.14233/ajchem.2023.27271. Full text in Research Archive Show summary

  The present research work reports the preparation of 100% deuterium oxide replaced the analogue of calcium oxalate monohydrate (COM) for the first time. The replacement of crystalline water in COM was carried out in a water-free environment by shaking a portion of the sample of COM with a calculated amount of deuterium oxide. Several experiments were conducted to study both partially deuterium oxide replaced samples and the composition of water/deuterium oxide in the liquid phase. Reflectance spectroscopy was used in analyzing the solid and liquid samples using special sample accessories. Furthermore, a full deuterium oxide replaced sample was exposed to atmospheric water to study the exchange of deuterium oxide molecules from the solid samples with water molecules. The results show that the full deuterium oxide replaced COM can be prepared using a suitable water-free environment. The infrared spectra of these samples clearly show that the water molecules in the crystal structure were replaced by deuterium oxide molecules assuming identical positions in the crystal structure. However, the bands arising from the deuterium oxide molecules were narrower than the bands due to water molecules. The analysis of the liquid samples during the partial deuterium oxide replacement shows that the replacement of the water of crystallization by deuterium oxide is 60% after 6 h of shaking. The full deuterium oxide replaced sample exposed to atmospheric water shows that the replacement of deuterium oxide by water molecules from the vapour phase is a slow process.

• Christy, Alfred Antony; Rathnaweera, Thilini Nisansala & Halanayake, Kalana Dasunpriya (2021). Desiccant Properties Comparison of Natural Bio-polymers. Journal of Applied Sciences. ISSN 1812-5654. 21(1), p. 1–9. doi: 10.3923/jas.2021.1.9. Full text in Research Archive Show summary

  Background and Objective: Desiccants are substances used in the dehumidification process which is vital in order to avoid the degradation of materials. Silica gel is the most prominent type of desiccant used and today the world has developed an interest in bio-polymers due to certain demerits of silica. Hence this study was conducted to investigate the desiccant properties of the four commercial flours wheat, corn, potato and gram and to compare them with the common silica gel desiccant. Materials and Methods: The bio-polymers were dried under vacuum at 120°C and were studied over time using Near-Infrared spectroscopy for their-OH combination peak which appears at around 5200 cm–1 and the derivative spectra were analyzed to recognize the specific-OH groups involved in the hydrogen bonding process. Further, the gravimetric analysis was used to study the rate of adsorption and their long term efficacies were detected using data loggers. Results: The results clearly indicated that adsorption of water occurs at C1, C2+C3, C4 and C6-OH groups for wheat and corn flour while potato and gram flour showed only three peaks attributing to C1, C2+C3 and C6-OH. Further, it was observed that C1 and C2+C3-OH groups have a similar and the highest rate. Conclusion: The rates of adsorption of all flours were greater than both analytical grade and commercial silica while corn flour was found to be an outstanding desiccant compared to conventional silica desiccant.

• Christy, Alfred Antony & Sivarukshy, Pathmanathan (2021). Comparison of adsorption properties of commercial silica and rice husk ash (RHA) silica: A study by NIR spectroscopy. Open Chemistry. 19(1), p. 426–431. doi: 10.1515/chem-2021-0044. Full text in Research Archive
• Jayathilake, Madhawa; Rudra, Souman & Christy, Alfred Antony (2021). Effect of co-liquefaction of lignin and laminaria saccharina on optimization of bio-oil yield. Energy Conversion and Management: X. doi: 10.1016/j.ecmx.2021.100151. Full text in Research Archive
• Jayathilake, Madhawa; Rudra, Souman; Akhtar, Naureen & Christy, Alfred Antony (2021). Characterization and Evaluation of Hydrothermal Liquefaction Char from Alkali Lignin in Subcritical Temperatures. Materials. 14(11). doi: 10.3390/ma14113024. Full text in Research Archive
• Christy, Alfred Antony; Phetcharee, Kulpriya & Hadsarung, Rungsima (2020). Characterization of Silica Extracted from Rice Husk by NIR Spectroscopy and its Application in Separation Science. Key Engineering Materials. ISSN 1013-9826. 853, p. 243–247. doi: 10.4028/www.scientific.net/KEM.853.243. Full text in Research Archive
• Shanmugaratnam, Sivagowri; Velauthapillai, Dhayalan; Christy, Alfred Antony; Ravirajan, Punniyamoorthy & Shivatharsiny, Yohi (2019). CoS2/TiO2 Nanocomposites for Hydrogen Production under UV Irradiation. Materials. 12(23), p. 1–9. doi: 10.3390/ma12233882. Full text in Research Archive Show summary

  Transition metal chalcogenides have intensively focused on photocatalytic hydrogen production for a decade due to their stronger edge and the quantum confinement effect. This work mainly focuses on synthesis and hydrogen production efficiencies of cobalt disulfide (CoS2)-embedded TiO2 nanocomposites. Materials are synthesized by using a hydrothermal approach and the hydrogen production efficiencies of pristine CoS2, TiO2 nanoparticles and CoS2/TiO2 nanocomposites are compared under UV irradiation. A higher amount of hydrogen production (2.55 mmol g−1) is obtained with 10 wt.% CoS2/TiO2 nanocomposite than pristineTiO2 nanoparticles, whereas no hydrogen production was observed with pristine CoS2 nanoparticles. This result unveils that the metal dichalcogenide–CoS2 acts as an effective co-catalyst and nanocrystalline TiO2 serves as an active site by effectively separating the photogenerated electron–hole pair. This study lays down a new approach for developing transition metal dichalcogenide materials with significant bandgaps that can effectively harness solar energy for hydrogen production.

• Fernando, H.A.; Raveendran, Praveena; Christy, Alfred Antony & Velauthapillai, Dhayalan (2019). Water Adsorption Properties of Titanium(IV) Oxide Embedded in Multiwalled Carbon Nanotubes (CNT). Key Engineering Materials. ISSN 1013-9826. 803, p. 182–186. doi: 10.4028/www.scientific.net/KEM.803.182. Full text in Research Archive
• Hiranmartsuwan, Peraya; Siangdee, Natthaya & Christy, Alfred Antony (2019). Surface Functionality and Water adsorption studies of alpha aluminium (111) oxide nanoparticles by Near Infrared Spectroscopy. Key Engineering Materials. ISSN 1013-9826. 803(104), p. 104–108. doi: 10.4028/www.scientific.net/KEM.803.104. Full text in Research Archive
• Christy, Alfred Antony (2018). Effect of UV Irradiation on Conjugated Linoleic Acid (9c 11t and 10t 12c). Journal of Chemical and Pharmaceutical Research. 10(8), p. 17–24. Full text in Research Archive Show summary

  This study was carried out to examine the effects of UVA irradiation on the Conjugated Linoleic Acid (CLA) isomers; 9c11t CLA and 10t12c CLA. CLA 9c11t free fatty acid (90%) and 10t12c-Octadecadienoic acid methyl ester (90%) samples in UV transparent cuvettes sealed under nitrogen gas were subjected to UVA irradiation at 365 nm. About four drops of each sample were taken out at regular intervals. These irradiated samples were analyzed using IR spectroscopy and Gas Chromatography (GC). The second derivative profiles of the IR spectra of UVA irradiated 9c11t CLA and 10t12c CLA show the decrease in intensity of the peaks at wavenumbers at 944 and 986. Furthermore, a slight increase in the intensity of the peak at around 967/cm and a slight blue shift of the peak at 984 to 988/cm are also observed. The GC peaks corresponding to tt CLA isomers increase in intensity showing the isomerization of methylene interrupted 18:2 linoleic acid to tt isomers of Conjugated Linoleic Acids. Furthermore, formation of oleic acid (!8:1 9c) in the irradiated sample of 9c11t free fatty acid and formation of oleic and elaidic acid (18:1 9t) in the irradiated sample of 10t12c methyl ester also observed. The results clearly indicate the depletion of conjugated linoleic acids during UV irradiation.

• Prathumsuwan, Thitarat; Christy, Alfred Antony & Thorstensen, Rein Terje (2018). Hydration Chemistry of Cement Studied by Near Infrared Spectroscopy. Key Engineering Materials. ISSN 1013-9826. 765 KEM, p. 309–313. doi: 10.4028/www.scientific.net/KEM.765.309. Full text in Research Archive
• Sangpongpitthaya, Tanyapa; Christy, Alfred Antony & Thorstensen, Rein Terje (2018). Quantitative Determination of Calcium Hydroxide by using Near Infrared Spectroscopy. Key Engineering Materials. ISSN 1013-9826. 765, p. 300–304. doi: 10.4028/www.scientific.net/KEM.765.300. Full text in Research Archive
• Christy, Alfred Antony & Rifla, Raziq (2017). Determination Of Kinetic Parameters For The Thermally Induced Isomerization Of Methyl Linolenate. Advances in Natural and Applied Sciences. ISSN 1995-0772. 11(8), p. 604–612. Full text in Research Archive
• Christy, Alfred Antony & Soonthenhut, Siraporn (2017). Water Structure in Proteins in Solid State Studied by Near Infrared Spectroscopy. Key Engineering Materials. ISSN 1013-9826. 735 KEM, p. 168–172. doi: 10.4028/www.scientific.net/KEM.735.168. Full text in Research Archive
• Angkuratipakorn, Thamonwan; Singkhonrat, Jirada & Christy, Alfred Antony (2017). Comparison of Water Adsorption Properties of Cellulose and Cellulose Nanocrystals Studied by Near-Infrared Spectroscopy and Gravimetry. Key Engineering Materials. ISSN 1013-9826. 735 KEM, p. 235–239. doi: 10.4028/www.scientific.net/KEM.735.235. Full text in Research Archive
• Christy, Alfred Antony (2017). An Insight into the Isomerization Chemistry of Methyl Linolenate. Journal of Chemical and Pharmaceutical Research. 9(9), p. 140–145. Full text in Research Archive
• Christy, Alfred Antony (2017). Changes in Unsaturated Fatty Acid Profiles of Some Vegetable Oils during Frying at Medium Frying Temperature. Journal of Chemical and Pharmaceutical Research. 9(10), p. 223–226. Full text in Research Archive
• Christy, Alfred Antony (2016). Water adsorption properties of free and dehydrated β-cyclodextrin studied by near infrared spectroscopy and gravimetry. Key Engineering Materials. ISSN 1013-9826. 689, p. 143–147. doi: 10.4028/www.scientific.net/KEM.689.143. Full text in Research Archive
• Christy, Alfred Antony & Fernando, N.R. (2016). Thermally induced chemical reactions in castor oil studied by infrared spectroscopy and gas chromatography: Determination of activation energy for the dehydration of ricinoleic acid. Advances in Natural and Applied Sciences. ISSN 1995-0772. 10(13), p. 146–156. Full text in Research Archive
• Christy, Alfred Antony & Arachchi, Subashini L. (2016). Thermally Induced Cis-Trans Isomerisation in Trilinolein Studied by Infrared Spectroscopy and Gas Chromatography. Advances in Natural and Applied Sciences. ISSN 1995-0772. 10(4), p. 168–176. Full text in Research Archive
• Christy, Alfred Antony (2016). Heat induced synthesis of linolenic acid isomers-A reference standard. Advances in Natural and Applied Sciences. ISSN 1995-0772. 10(17), p. 19–22. Full text in Research Archive
• Christy, Alfred Antony (2015). The Adsorption of Water Molecules on Titanium (iv) Oxide Surface as Studied by Near Infrared Spectroscopy. Advances in Natural and Applied Sciences. ISSN 1995-0772. 9(14), p. 14–19. Full text in Research Archive
• Christy, Alfred Antony (2015). Insights into the Chemistry of Adsorption of Water Molecules by Cyclodextrins as Studied by Near Infrared Spectroscopy. Advances in Natural and Applied Sciences. ISSN 1995-0772. 9(14), p. 7–13. Full text in Research Archive
• Christy, Alfred Antony (2015). Adsorption and Dehydration of Water Molecules from α, β and γ Cyclodextrins-A study by TGA analysis and gravimetry. Advanced Materials Research. ISSN 1022-6680. 1120-1121, p. 886–890. doi: 10.4028/www.scientific.net/AMR.1120-1121.886. Full text in Research Archive
• Christy, Alfred Antony (2014). Comparison of water adsorption characteristics of oligo and polysaccharides of α-glucose STUDIED by near infrared spectroscopy. Advanced Materials Research. ISSN 1022-6680. 1035, p. 476–482. doi: 10.4028/www.scientific.net/AMR.1035.476. Full text in Research Archive Show summary

  The adsorption properties of water molecules on oligo and polysaccharides are attributed to the OH groups of the glucose rings in the molecules. The water molecules are adsorbed onto OH groups by hydrogen bond formation. Near infrared spectroscopic and gravimetric techniques were used in analysing the adsorption characteristics of malto-oligosaccharides and some polysaccharides. Near infrared spectra of the dry oligo and polysaccharides were acquired during the adsorption of water molecules at a relative humidity of 50-55%. The amounts of water adsorbed by the samples were also recorded by an analytical balance. Second derivative techniques were used in decomposing the OH combination frequencies of the adsorbed water molecules in the region 5300-5000 cm -1.The results indicate that the water molecules are adsorbed on to C2 and C3-OH groups at a higher rate compared to the adsorption onto C1-OH groups in the molecules. Adsorption also takes place onto the ethereal oxygen atoms in the glucose rings in malto-oligosaccarides. The gravimetric results show that the adsorption of water molecules increases with the number of glucose units in the malto-oligosaccharides except maltotriose which has the highest adsorption over a period of 75 minutes. Furthermore, the adsorption characteristics of amylose and amylopectin are similar.

• Christy, Alfred Antony (2014). Adsorption of alcohols onto zinc selenide (ZnSe) crystal surface. Advanced Materials Research. ISSN 1022-6680. 1035, p. 277–280. doi: 10.4028/www.scientific.net/AMR.1035.277. Full text in Research Archive
• Christy, Alfred Antony (2014). The Nature of Silanol Groups on the Surfaces of Silica, Modified Silica and Some Silica Based Materials. Advanced Materials Research. ISSN 1022-6680. 998-999, p. 3–10. doi: 10.4028/www.scientific.net/AMR.998-999.3. Full text in Research Archive Show summary

  Silica gel, a material that is produced from the condensation polymerisation of silicic acid, contains surface silanol groups formed during the condensation. The silanol groups on the surface are mostly of free and vicinal silanol groups. These silanol groups can be modified in several different ways. Thermal treatment and hydrothermal treatment can be carried out to alter the concentration proportions between free and hydrogen bonded silanol groups on the surface. They can also be chemically treated with suitable chlorosilanes to modify the silanol groups into polar or non polar materials that can be used in separation science.This article explores the chemical nature of silanol groups on the surfaces of different materials. Near infrared reflectance spectroscopy was used as the instrumental technique in this study. The silanol groups classifications were made by analyzing the near infrared spectra obtained during the adsorption of water molecules. Absorption of the combination frequencies of water molecules in the region 5500- 5000 cm -1 were used in characterizing the silanol groups on the surfaces. Second derivative technique was employed in the resolution and detailed analysis of these absorptions.The study reveals that the materials contain free, vicinal and gem silanol groups. Silica gel contains free and vicinal silanol groups, thermally treated silica gel contains fewer vicinal silanol groups compared to the base silica gel, and hydrothermally treated silica gel contains higher concentrations of vicinal silanol groups compared to the base silica gel. Furthermore, the chemically modified silica gel contains vicinal or geminal silanol groups depending on the type of functionality introduced.

• Christy, Alfred Antony; Barth, Tanja & Francis, George William (2014). Preliminary photochemical studies of fluorene in various aqueous media. American Journal of Scientific and Industrial Research. 5, p. 97–103. doi: 10.5251/ajsir.2014.5.3.97.103. Full text in Research Archive Show summary

  The current study investigates the direct photochemical degradation of aqueous fluorene with the aid of a 125W polychromatic medium, pressure Hg lamp. The purpose was to test the effectiveness of the lamp in irradiation using fluorene spiked solution as substrate. A 700 ml volume of fluorene solution of 0.002 mg/l was irradiated batch-wise at 1, 3, 6, 12, 18, 24 and 48 h. The amount of fluorene removal was studied for fluorene solutions prepared from , neutral (distilled water), acidic (by adjusting pH with hydrochloric acid, HCl), basic (by adjusting pH with sodium hydroxide, NaOH) and saline (addition of sodium chloride, NaCl) solutions and there was 95.95, 92.35, 96.65 and 97.15 % removal respectively after 48 h of irradiation. The major degradation product identified was fluorenone. The different media did not significantly affect the rate of fluorene degradation.

• Christy, Alfred Antony (2013). Chemistry of desiccant properties of carbohydrate polymers as studied by near-infrared spectroscopy. Industrial & Engineering Chemistry Research. ISSN 0888-5885. 52(12), p. 4510–4516. doi: 10.1021/ie302199k. Full text in Research Archive Show summary

  The combination frequency of water molecule in near-infrared spectroscopy is very useful for studying water molecular adsorption on solid surfaces. The absorption is purely from water molecules, and the variation in the absorption bands reflects the change in the environment of the water molecules on a surface. This variation, in turn, reflects the nature of the functional groups on the surface. Recently, Christy used this information in combination with second-derivative techniques to probe the surface of hydrothermally treated silica gel samples (Ind. Eng. Chem. Res.2011, 50, 5543). In this work, a similar approach was used in studying the surface OH groups in carbohydrate polymers and their behavior toward water molecular adsorption. Not only second-derivative profiles but also fourth-derivative profiles of the near-infrared spectra were used in revealing the adsorption behavior of the OH groups on the polymer surface. Carbohydrate polymers such as amylose amylopectin, cellulose, and starch samples were used in this study. After being heated and evacuated at 120 °C, the samples were exposed to air, and the evolving changes on the surfaces of the samples were followed by near-infrared spectroscopy. Furthermore, the effectiveness of the samples in adsorbing water molecules was followed by monitoring the mass of water adsorbed. These investigations formed the basis for understanding how the OH groups on the carbohydrate polymers adsorb water molecules. The results clearly reveal that carbohydrate polymers such as amylose, amylopectin, and cellulose have three OH groups of different polarities and that the OH groups attached to C2 and C3 positions in the monomer glucose units adsorb water molecules faster than the C6-OH group. Furthermore, the adsorption of water molecules in amylose and amylopectin follows the same pattern during the first hour, irrespective of the variation in their structure.

• Christy, Alfred Antony (2013). Near Infrared Spectroscopic Study on the Adsorption of Methanol on Silica Gel. Advanced Materials Research. ISSN 1022-6680. 650, p. 150–155. doi: 10.4028/www.scientific.net/AMR.650.150. Full text in Research Archive Show summary

  The silanol groups on Silica gel surface are sites for adsorption of polar molecules. Alcohols and other polar molecules are easily adsorbed by forming hydrogen bondings with OH groups on silica gel surface. A study on the adsorption of methanol on silica gel was carried out by using NIR spectroscopy in combination with ssecond derivative techniques. Four of the well characterised silica gel samples were used in this study. Each of the silica gel (0.25g) samples with different surface areas and silanol number was pressed into a small disc, placed in a glass vial and the physically adsorbed water molecules from the surface of the silica gel particles were removed by heating the sample to 200 °C under vacuum. The near infrared spectra of the cooled sample was recorded by a Perkin Elmer spectrum one NIR spectrometer equipped with a transflectance accessory and a deuterated triglycine detector at a resolution of 16 cm-1. The glass vial was then opened and a tiny tube filled with methanol was inserted in the glass vial. Then the near infrared spectra of the sample during the adsorption of methanol were recorded at regular time intervals until there is no apparent change in the spectra. The second derivative profiles of the spectra were obtained using the instruments' software. The mass of the silica gel pellet was determined by an analytical balance and the methanol adsorbed on the surface was calculated. The number of methanol layers on the silica gel surface was calculated using the silica gel particle characteristics of the samples. The results show that the adsorption evolution of methanol progresses on the samples and the surface was covered by a mono layer within the first 60 minutes. Furthermore, it appears that the adsorption of multilayer on methanol starts after all the surface silanol groups are exhausted.

• Christy, Alfred Antony (2013). The nature of rest silanol groups on the surfaces of silica based solid phase extraction materials. Advanced Materials Research. ISSN 1022-6680. 650, p. 66–71. doi: 10.4028/www.scientific.net/AMR.650.66. Full text in Research Archive Show summary

  Chemically bonded solid phase materials are very important in separation chemistry. The chemically modified silica gel contains rest silanol groups that can affect the retention properties when they are used for separation of compounds. Some commercially available solid phase extraction (SPE) materials based on silica gel were analysed for rest silanol groups by near infrared spectroscopy. The combination frequency of the water molecules in the 5500- 5000 cm -1 region was used in identifying the nature of water molecules on the surface and the information was used to identify the types of silanol groups on the surface. Second derivative technique was employed in the detailed analysis. Nine different SPE materials including C18, C8, C6H5, NH2, OH, CN, SiOH, SA (SCX) and SB (SAX) were examined by near infrared spectroscopy for rest silanol groups. The results show that the non-polar and polar stationary phases contain vicinal silanol groups and the ion exchange solid phase materials contain free, vicinal and geminal silanol groups.

• Christy, Alfred Antony; Nkansah, Marian Asantewah & Barth, Tanja (2012). Catalytic oxidation and reduction of polycyclic aromatic hydrocarbons (PAHs) present as mixtures in hydrothermal media. Polycyclic aromatic compounds (Print). ISSN 1040-6638. 32(3), p. 408–422. doi: 10.1080/10406638.2012.663451. Full text in Research Archive Show summary

  The reactivity of fluorene, anthracene and fluoranthene under oxidation and reduction conditions has been investigated in this study. This project looks at catalytic and green approaches of converting PAH to less toxic and/or less stable derivatives that are amenable to further degradation. Hydrothermal reactions have been performed at 300 oC with pure H2O and Nafion-SiO2 catalyst for oxidation, and pure H2O, HCOOH, Pd-C and Nafion-SiO2 catalysts for reductive hydrogenation. Time series has been performed for both the oxidation and hydrogenation systems. The products of the reaction were identified and quantified by the use of Gas Chromatography-Mass Spectrometry and the NIST Library. The reaction products include oxidised products of anthracene and fluorene; and hydrogenated derivatives of anthracene and fluoranthene. Fluoranthene did not undergo oxidation; and fluorene did not undergo hydrogenation under the conditions of this research.

• Christy, Alfred Antony (2012). Effect of Heat on the Adsorption Properties of Silica Gel. International Journal of Engineering and Technology. ISSN 1793-8236. 4(4), p. 484–488. doi: 10.7763/ijet.2012.v4.416. Full text in Research Archive Show summary

  Adsorption properties of silica gel have been attributed to the surface hydroxyl groups of silica gel. Some hydroxyl groups are free standing and called free silanol groups. Some are hydrogen bonded to neighbouring silanol groups. Christy has shown that a high silanol number and a balanced concentration proportionality between these two different types of hydroxyl groups is necessary for effective adsorption of water molecules. Thermal treatment of silica gel samples alters the proportions of these groups and the above fact was investigated by using thermally treated silica gel samples. Two silica gel samples of varying surface areas and silanol numbers were dried under vacuum at 200 oC and their adsorption characteristics were followed by using NIR spectroscopy. Then the samples were subjected to heating at 350, 450, 600 degrees to cause changes in the concentrations of the surface silanol groups and their surface and adsorption characteristics were followed. The results clearly indicate that the heating process both remove free and hydrogen bonded silanol groups and alter the ratio between the two. Furthermore, the heating causes reduction in silanol umber and upsets the balance in the proportionality of the silanol groups for effective adsorption of water molecules.

• Nkansah, Marian Asantewah; Christy, Alfred Antony; Barth, Tanja & Francis, George William (2012). The use of lightweight expanded clay aggregate (LECA) as sorbent for PAHs removal from water. Journal of Hazardous Materials. ISSN 0304-3894. 217, p. 360–365. doi: 10.1016/j.jhazmat.2012.03.038. Full text in Research Archive Show summary

  Lightweight expanded clay aggregate (LECA) has been explored as a sorbent for the removal of PAHs (phenanthrene, fluoranthene and pyrene) from water. The efficacy of LECA as a sorbent for PAHs was assessed using contact time, mass of sorbent and sorption isotherms in a series of batch experiments. Maximum (optimum) sorption was reached at 21 h after which the amount of PAHs sorbed remained almost constant. Batch experiments were conducted by shaking a 100 ml solution mixture of individual PAHs (containing 0.02 mg/L) with LECA. The maximum sorption was 70.70, 70.82 and 72.12%, respectively for phenanthrene, fluoranthene and pyrene when a mass of 0.2 g of sorbent was used. There was an increase in sorption as a result of an increase in mass of sorbent until a maximum was reached at a mass of 4.0 g LECA with 92.61, 93.91 and 94.15% sorption of phenanthrene, fluoranthene and pyrene respectively. Sorption data were fitted to the linearised forms of the Freundlich and Langmuir isotherm models to determine the water-LECA partitioning coefficient. Physical sorption caused by the aromatic nature of the compounds was the main mechanism that governed the removal process while the hydrophobicity of the PAHs also influenced the sorption capacity. LECA can be used as an alternative method for aqueous PAHs removal.

• Francis, George William; Christy, Alfred Antony & Øygarden, Jostein (2012). Pyrolytic formation of pyrolytic aromatic hydrocarbons from sesquiterpenes. Food Chemistry. ISSN 0308-8146. 135(3), p. 1316–1322. doi: 10.1016/j.foodchem.2012.06.033. Full text in Research Archive
• Christy, Alfred Antony; Svendsen, Monica Lian & Francis, George William (2011). Pyrolytic formation of polyaromatic hydrocarbons from steroid hormones. Food Chemistry. ISSN 0308-8146. 124(4), p. 1466–1472. doi: 10.1016/j.foodchem.2010.07.109. Full text in Research Archive

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• Christy, Alfred Antony (2021). General Chemistry: The Basics. McGraw-Hill. ISBN 9781307692228. 450 p. Full text in Research Archive
• Christy, Alfred Antony (2020). General Chemistry: The basics. Mcgraw Hill. ISBN 9781307606522. 412 p. Full text in Research Archive

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• Christy, Alfred Antony (2022). Organic Chemistry-Fatty acids. Full text in Research Archive
• Christy, Alfred Antony (2022). Session Chairman-Material science conference. Full text in Research Archive
• Christy, Alfred Antony (2022). Organic Chemistry Basics- Esters and related compounds. Full text in Research Archive
• Christy, Alfred Antony (2022). Instrumental analysis- Hydration of Cement studied by Near Infrared Spectroscopy. Full text in Research Archive
• Storaas, Vigleik & Christy, Alfred Antony (2022). Instrumental analysis- UV and Infrared spectroscopy. Full text in Research Archive
• Christy, Alfred Antony (2020). Near Infrared spectroscopy in Industry: The importance and determination of calcium hydroxide in cement. Full text in Research Archive
• Phetcharee, Kulpriya; Hadsarung, Rungsima & Christy, Alfred Antony (2020). Characterization of Silica Extracted from Rice Husk by NIR Spectroscopy and its Application in Separation Science. Full text in Research Archive
• Christy, Alfred Antony (2019). The importance and determination of calcium hydroxide in cement by Near infrared spectroscopy. Full text in Research Archive
• Christy, Alfred Antony (2019). Dehydration of cement studied by Therogravimetric analysis. Full text in Research Archive
• Christy, Alfred Antony (2018). Importance of calcium hydroxide or its Dehydration studied by TGA analysis. Full text in Research Archive
• Christy, Alfred Antony & Thorstensen, Rein Terje (2018). Quantitative determination of calcium hydroxide in concrete by near infrared spectroscopy. Full text in Research Archive
• Christy, Alfred Antony (2018). Water Adsorption Properties of Malto-Oligosaccharides and Cyclodextrins Studied by near Infrared Spectroscopy and Gravimetry. Full text in Research Archive
• Christy, Alfred Antony (2018). operational principles of spectroscopic techniques. Full text in Research Archive
• Christy, Alfred Antony (2018). Quantitative Determination of Calcium Hydroxide in Cement by Near Infrared Spectroscopy. Full text in Research Archive
• Christy, Alfred Antony (2018). Applications of Near Infrared Spectroscopy. Full text in Research Archive
• Christy, Alfred Antony (2018). Applications of NIR spectroscopy in Material Science. Full text in Research Archive
• Christy, Alfred Antony (2017). Some applications of NIR spectroscopy in studying water structure in material science. Full text in Research Archive
• Christy, Alfred Antony (2017). Heat Induced Isomerization and auto oxidation reactions of C18 unsaturated fatty acids in edible oils. Full text in Research Archive
• Christy, Alfred Antony (2017). Applications of Near Infrared Spectroscopy in Material Science- Analysis of hydroxyl groups on surfaces. Full text in Research Archive
• Christy, Alfred Antony (2017). Thermal Stability Of The Isomers Of Linolenic Acid. Full text in Research Archive
• Christy, Alfred Antony (2017). The state of water in cement studied by near infrared spectroscopy. Full text in Research Archive
• Christy, Alfred Antony (2017). Titanium oxide and water adsorption. Full text in Research Archive
• Christy, Alfred Antony (2017). spectroscopy and chromatography. Full text in Research Archive
• Christy, Alfred Antony (2017). instrumental analysis. Full text in Research Archive
• Christy, Alfred Antony (2016). Water adsorption properties of free and dehydrated β-cyclodextrin studied by near infrared spectroscopy and gravimetry. Full text in Research Archive
• Christy, Alfred Antony (2016). Applications of near infrared spectroscopy in the analysis of hydroxyl groups on solid samples. Full text in Research Archive
• Christy, Alfred Antony (2016). Applications of Near Infrared Spectroscopy in the Analysis of Water Adsorption on Hydroxyl Groups of solid samples. Full text in Research Archive
• Christy, Alfred Antony (2016). Thermally induced cis-trans isomerization in trilinolein studied by infrared spectroscopy and gas chromatography. Full text in Research Archive
• Christy, Alfred Antony (2016). UV/Visible and Infrared spectroscopy. Full text in Research Archive
• Christy, Alfred Antony (2016). Applications of Near Infrared Spectroscopy in the Analysis of Surface Hydroxyl Groups on solid surfaces. Full text in Research Archive
• Christy, Alfred Antony (2016). Thermally Induced Dehydration of Castor Oil Studied by Infrared Spectroscopy and Gas Chromatography. Full text in Research Archive
• Christy, Alfred Antony (2016). Spectroscopic techniques in Chemistry. Full text in Research Archive
• Christy, Alfred Antony (2015). Adsorption and dehydration of water molecules from alpha, beta and gamma cyclodextrins-A study by TGA and gravimetry. Full text in Research Archive
• Christy, Alfred Antony (2015). Water adsorption characteristics of cyclodextrins studied by NIR spectrometry and gravimetry. Full text in Research Archive
• Christy, Alfred Antony (2015). Instrumental analysis: Chromatography. Full text in Research Archive
• Christy, Alfred Antony (2015). Frying in edible oils: How safe it is? Full text in Research Archive
• Christy, Alfred Antony (2015). Instrumental analysis: Spectroscopy. Full text in Research Archive
• Christy, Alfred Antony (2014). Applications of Near Infrared Spectroscopy in the Analysis of Water Adsorption on Hydroxyl Groups of solid samples. Full text in Research Archive
• Christy, Alfred Antony (2014). Theory and Practice of Mass spectrometry and Nuclear Magnetic Resonance Spectrometry. Full text in Research Archive
• Christy, Alfred Antony (2014). Theory and practice of UV and Infrared spectroscopy. Full text in Research Archive
• Christy, Alfred Antony (2013). A COMPARATIVE STUDY OF THE CHEMISTRY OF DESICCANT PROPERTIES BETWEEN OLIGOSACCHARIDES AND POLYSACCHARIDES BY NIR SPECTROSCOPY. Full text in Research Archive
• Christy, Alfred Antony (2013). Water adsorption characteristics of acyclic oligosaccharides of α-glucose studied by Near Infrared Spectroscopy. Full text in Research Archive
• Christy, Alfred Antony (2013). The adsorption chemistry of polysaccharide dessicants. Full text in Research Archive
• Christy, Alfred Antony (2013). Hydration and dehydration of oligosaccharides studied by NIR spectroscopy. Full text in Research Archive
• Christy, Alfred Antony (2013). Chemistry of the desiccant properties of oligosaccharides and carbohydrate polymers. Full text in Research Archive
• Christy, Alfred Antony (2012). Effect of modifications of silanol groups on silica gel. Full text in Research Archive
• Christy, Alfred Antony (2012). Effect of tailoring surface silanol groups on adsorption properties of silica gel-A near infrared spectroscopic study. Full text in Research Archive
• Christy, Alfred Antony (2012). Pyrolysis of sesquiterpenes yields polyaromatiske hydrocarbons. Full text in Research Archive
• Christy, Alfred Antony (2012). State of water molecules and silanol groups in Opal minerals and carbohydrates. Full text in Research Archive
• Christy, Alfred Antony (2012). Research and teaching with Erasmus students. Full text in Research Archive
• Christy, Alfred Antony (2012). Study of adsorption of alcohol on silica gel. Full text in Research Archive
• Christy, Alfred Antony (2012). Rest silanol groups on solid phase extraction materials. Full text in Research Archive
• Christy, Alfred Antony (2012). The nature of hydroxyl groups on silica gel surface. Full text in Research Archive
• Christy, Alfred Antony (2012). Transforming a service laboratory into a research institute. Full text in Research Archive
• Christy, Alfred Antony (2011). Effect of hydrothermal treatment on adsorption properties of silica gel. Full text in Research Archive
• Christy, Alfred Antony; Stawski, Dawid; Połowiński, S & Bellmann, C (2011). Deposition of Polyaniline Layers on Polypropylene Nonwoven. Full text in Research Archive
• Christy, Alfred Antony; Miroslav, B; Kluvanec, Daniel & Illasova, L (2011). STATE OF WATER MOLECULES AND SILANOL GROUPS IN OPAL MINERALS: A NEAR INFRARED SPECTROSCOPIC STUDY OF OPALS FROM SLOVAKIA. Full text in Research Archive
• Nkansah, Marian Asantewah; Christy, Alfred Antony & Barth, Tanja (2011). A Preliminary Study on Adsorption of PAH from Water by (Lightweight Expanded Clay Aggregate) LECA. Full text in Research Archive
• Nkansah, Marian Asantewah; Christy, Alfred Antony & Barth, Tanja (2011). Catalytic redox hydrous pyrolysis degradation of anthracene, fluorene and fluoranthene. Full text in Research Archive
• Christy, Alfred Antony (2011). State of water molecules and silanol groups in Opal minerals: A near infrared spectroscpic study of opals from Slovakia. Full text in Research Archive

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