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The purpose of this study was to develop the augmented reality (AR) educational program combined with the instructional guidance for supportive learning, which enhanced the thinking process cooperative discussion and problem-solving skills in chemistry subject.

The method used the quasi-experimental research design. Of the 45 students who attended this experiment, only 25 with low achievement qualified in operating the AR learning system of saponification and transesterification environment (ARLS-STE) system.

These results confirmed that the AR educational program could have increased substantial benefits in improvements of students’ knowledge and the ability of the thinking process for the participants with the lowest score. In semi-structured interviews, most of participants enjoyed manipulating the ARLS-STE system, which was realistic, motived and interesting for learning science subjects.

The low-achieving students have often been known with a low learning capability, and they lack in developing constructional knowledge, despite being keen for learning. Regarding educational concerns for this population, providing orientated learning and supportive materials could increase their learning effects. Virtual worlds are an efficient learning tool in educational setting. The AR can offer visual concepts and physical interaction for students with low achievement in learning. Thus, this study investigates the acceptability of an educational program designed in the ARLS-STE, which involves the learning effects of academic knowledge and the capability of thinking process for students with low achievement. The ARLS-STE system was developed for this proposal, based upon the marker-based AR technologies combined with hands-on manipulation.

The purpose of this paper is to provide a critical and in‐depth review of the present status and recent developments in synthetic methodologies, reaction engineering, process design and quality control aspects associated with the manufacture of mono and multifunctional acrylate monomers.

This paper reviews commercially important UV cure mono and multifunctional acrylate monomers. It covers their synthesis, catalyst, and appropriate solvents for azeotropic removal of byproducts. The detail discussion on catalysis, basis of design of reactors and commercial plant and the process engineering associated with the manufacture has been supported through citation of synthesis of various acrylate monomers. The methodologies adopted for determination of physical, chemical and compositional characterisation of acrylate monomers have been presented. In addition, the guidelines regarding the bulk storage and commercial handling of acrylates have been reviewed.

The reaction engineering of esterification reaction between acrylic acid and polyol has been worked out to provide the basis for selection of reactors. The reaction has been modeled as a series – parallel complex reaction for providing explanation for generation of various byproducts/adducts and multiple esters.

The detailed discussion on formation, characterisation and treatment of Michael adducts and purification of acrylate monomers will be relevant for new researchers for further development. A review of guidelines on selection of homogenous and heterogeneous catalysts for synthesis of acrylate monomers has been presented.

Since the related literature on acrylate monomers is scarce, scattered and proprietary, the consolidated coverage in one paper will be useful.

The aim of this paper is to focus on the production of mixed‐synthetic diester base oils from the waste of electrochemical production of sebacic acid (mixtures of methyl esters of dicarboxylic acids, HOOC(CH₂)nCOOH, n=4, 6, 8).

The mixtures of methyl esters of dicarboxylic acids ((CH₂)n, n=4, 6, 8) are transesterified by pure alcohols and also different mixtures of aliphatic monohydric alcohols, C6‐C10 of iso‐ and normal structure, in the presence of a new catalyst system (tetra‐n‐butyl orthotitanate, Ti(O‐n‐Bu)₄). The effects of starting materials ratios on the reaction progress and characteristic features of the obtained diester oils have been studied.

The obtained mixed diester oils showed similar thermal properties and low pour point (minimum −70°C), and improved viscosity‐temperature properties compared with commercially available dioctyl sebacate (DOS) and dioctyl adipate (DOA) diester oils.

Because of the complexity of the obtained mixture, it was impossible to study the structure and composition of the obtained products by modern techniques such as high field NMR spectroscopy.

The mixtures of methyl esters of dicarboxylic acids obtained from different batches of sebacic acid production have different molar ratios and must be analyzed before use. The process is based on transesterification reactions of methyl esters of mixture of the aliphatic dicarboxylic acids ((CH₂)n, n=4, 6, 8) by mixture of aliphatic alcohols having iso‐ and normal structure in the presence of a new transesterification catalyst (mixture of p‐toluene sulfonic acid and tetra‐n‐butyl orthotitanate). The obtained mixed diester oils showed similar thermal properties, low pour point (minimum −70°C) and improved viscosity‐temperature properties compared with commercially available DOS and DOA diester oils.

The paper illustrates a new process for the production of mixed‐synthetic diester base oils.

The purpose of this study is to improve the tribological characteristics of cotton-biolubricant by adding nanoparticles at extreme pressure (EP) conditions in comparison with commercial lubricant SAE-40.

This research involved the synthesis of cotton-biolubricant by transesterification process and then the addition of nanoparticles in it to improve anti wear (AW)/EP tribological behavior. SAE-40 was studied as a reference commercial lubricant. AW/EP characteristics of all samples were estimated by the four-ball tribo-tester according to the American Society for Testing and Materials D2783 standard.

The addition of 1-Wt.% TiO₂ and Al₂O₃ with oleic acid surfactant in cotton-biolubricant decreased wear scar diameter effectively and enhanced the lubricity, load-wear-index, weld-load and flash-temperature-parameters. This investigation revealed that cotton-biolubricant with TiO₂ nano-particle additive is more effective and will help in developing new efficient biolubricant to replace petroleum-based lubricants.

Cotton biolubricant with TiO₂ nano-particles appeared as an optimistic solution for the global bio-lubricant market.

No one has not studied the cotton biolubricant with nanoparticles for internal combustion engine applications at high temperature and EP conditions.

This study aims to find a new alternate source for biodiesel conversion. The alternate source must be easily available, and it should give more oil yield than available edible, inedible sources. To meet the fuel demand in the transportation sector with edible oil-based biodiesel causes food versus fuel crisis. In addition to this, it increases NO_x and CO₂ in the environment.

The present paper reviews the comparison of algae oil yield, fatty acid composition and its biodiesel properties’ effect on diesel engine characteristics.

Algae were the only source to fulfil fuel demand because its oil and biodiesel yield is higher than other sources. Algae can grow by capturing carbon dioxide from the environment, and its fatty acid composition is more suitable to run diesel engines.

There is an improvement in engine performance–emission tradeoff with algal biodiesel.

The purpose of this study is to modify guar gum (GG) into guar gum acetate (GGA) and phthaloyl guar gum (PHGG) by transesterification and phthaloylation, respectively.

GG has been modified into GGA through transesterification reaction between GG and vinyl acetate and PHGG through esterification reaction with phthalic anhydride. The modified GG was characterized by solubility test, Fourier-transform infra-red (FTIR) spectroscopy, proton nuclear magnetic resonance (¹H NMR) spectroscopy, X-ray diffractometry (XRD) and thermogravimetric analysis. Swelling properties of GGA and PHGG hydrogels in water were evaluated.

These two types of modified GG have better solubility such as in dimethyl sulfoxide and N,N-dimethylformamide but no true organosolubility was achieved. The modifications were confirmed through FTIR with new absorption peaks at 1,733 cm⁻¹ for GGA and 1,709 cm⁻¹ for PHGG coupled with observed substitution peaks at 1.80 to 2.20 ppm and 7.40 to 7.90 ppm, respectively, from ¹H NMR spectroscopies. XRD revealed both GGA and PHGG are less crystalline than native GG. GGA was found to be more thermally stable than native GG, whereas PHGG was slightly less thermally stable than native GG. The swelling property in distilled water for native GG, PHGG and GGA was 918.43 ± 46.62%, 537.04 ± 2.87% and 393.04 ± 13.42%, respectively.

The GGA and PHGG hydrogels are expected to be useful for biomedical fields such as tissue engineering and drug-delivery.

Modifications of native GG into GGA using vinyl acetate and PHGG using phthalic anhydride are novel.

The purpose of this paper is to speak about the production of biodiesel from waste cooking oil which serves as an alternate fuel in the absence of conventional fuels such as diesel and petrol. Though much research work was carried out using non-edible crops such as Jatropha and Pongamia, cooking oil utilized in bulk quantity is discarded as a waste. This is reused again as it contains more of esters that when combined with an alcohol in presence of an enzyme as a catalyst yields triglycerides (biodiesel).

The lipase producing strain Rhizopus oryzae and pure enzyme lipase is immobilized and treated with waste cooking oil for the production of FAME. Reaction parameters such as temperature, time, oil to acyl acceptor ratio and enzyme concentration were considered for purified lipase and in the case of Rhizopus oryzae, pH, olive oil concentration and rpm were considered for optimization studies. The response generated through each run were evaluated and analyzed through the central composited design of response surface methodology and thus the optimized reaction conditions were determined.

A high conversion (94.01 percent) was obtained for methanol when compared to methyl acetate (91.11 percent) and ethyl acetate (90.06 percent) through lipase catalyzed reaction at oil to solvent ratio of 1:3, enzyme concentration of 10 percent at 30°C after 24 h. Similarly, for methanol a high conversion (83.76 percent) was obtained at an optimum pH of 5.5, olive oil concentration 25 g/L and 150 rpm using Rhizopus oryzae when compared to methyl acetate (81.09 percent) and ethyl acetate (80.49 percent).

This research work implies that the acyl acceptors methyl acetate and ethyl acetate which are novel solvents for biodiesel production can also be used to obtain high yields as compared with methanol under optimized conditions.

The purpose of this paper is to demonstrate how opting for multiple contributors to the lowC economy and introducing new intelligent solutions allows a smooth transition to renewable fuels. Undoubtedly, biofuels are no longer everybody's darling. This is partly owed to the need to produce bio fuels at the lowest possible price and absent sustainability regulations or their enforcement like the European parliament initiated by banning bio fuels with not sufficient evidence of saving CO₂. But on the other hand, the end of cheap oil is clearly visible and it is clear that second generation lowC fuels may by no means be able to replace all of the worlds growing fuel consumption in a few years.

The paper presents a tri‐fold approach which has originated of two EU‐projects (SUGRE and RECODRIVE) based on reduction of the propulsion demand, intelligent powertrain configuration and the use of residues and waste as feedstock. The RECODRIVE approach tested in the European project with the same name introduces a quality management in fleet management which comprises procurement, driving and maintenance. This approach comprising also logistics should be able to reduce the propulsion demand at least by 10 per cent targeting 30 per cent and more.

Hybrid power trains are regenerating the braking energy and are reducing the propulsion demand by 15‐25 per cent in stop'n go traffic in cities. Parallel or power split hybrids may operate with phlegmatized and thus more efficient combustion engines, but serial hybrid electric power trains drive this characteristics, the extreme which is helpful introducing alternative fuels. They decouple the production of energy from the throttle command and allow for a more steady operation of the internal combustion engine.

By employing a serial hybrid power train simpler low‐RPM engines may be used which are modified to run on plant oils and other alternative fuels which are difficult to use in modern highly performing diesel engines. By reducing the propulsion demand, a higher share of alternative fuels based on natural feedstock may be achieved. This feedstock may be also amended by better utilising waste. The paper describes two examples. In Graz, used frying oil is collected to feed a transesterification plant and in Linköping waste from the meat industry is collected to produce biogas.

The approach enables the transport sector to increase the independence on oil at short‐term without the risk of putting a lot of venture capital in the wrong fuel or engine technology. The serial hybrid electric concept remains the basis for future solutions working on different end energy like hydrogen.

This study aims to improve the performance and to regulate the harmful emission from the diesel engine. For this purpose, palm oil biodiesel (POBD), waste cooking biodiesel (WCBD) and animal fat biodiesel (AFBD) are used for examination.

The transesterification process was followed to convert the three raw oils into biodiesels and the experiments are conducted at various loads with fixed 25 rps. Diesel as a reference fuel and three neat biodiesels are tested for emissions and performance. By training the experimental results in an artificial neural network (ANN), the best biodiesel was predicted.

The biodiesels are tested for significant fuel properties with the American Society for testing and materials standards and observed that kinematic viscosity, density and cetane number are recorded higher than diesel fuel. The fatty acid composition (FAC) from chromatography reveals the presence of unsaturated FAC is more in POBD (70.89%) followed by WCBD (57.67%) and AFBD (43.13%). The combustion pressures measured at every degree of crank angle reveal that WCBD and AFBD exhibited on far with diesel fuel. Compared to diesel fuel WCBD and AFBD achieved maximum brake thermal efficiency of 31.99% and 30.93% at 75% load. However, there is a penalty in fuel consumption and NOx emissions from biodiesels. On the other hand, low carbon monoxide, unburnt hydrocarbon emissions and exhaust smoke are reported for biodiesels. Finally, WCBD was chosen as the best choice based on ANN modeling prediction results.

There is no evident literature on these three neat biodiesel applications with the mapping of ANN modeling.

The paper presents the results of research carried out on esters of carbonic, adipic, and sebacic acids with respect to their use as components of fully synthetic lubricating oil produced from a polyalphaolefin base. Straight dicarboxylic acid esters were synthesized in a transesterification reaction of dimethyl carbonate, dimethyl adipate, and dimethyl sebacate with 2‐ethylhexanol and 3,5,5‐trimethylhexanol.

Oligomeric esters of adipic acid and sebacic acid were synthesized using neopentyl glycol, appropriate dimethyl adipate or dimethyl sebacate and 2‐ethylhexanol as the starting material. The basic physicochemical properties of esters were determined and their compatibility with synthetic oils were defined. They were also evaluated with respect to resistance under the influence of thermo‐oxidative factors, evaporation and susceptibility to hydrolytic decomposition. The selected esters were complemented with commercial additives to make up a fully synthetic lubricating oil with a polialphaolefin base. A special attention was paid to the effect of ester compounds on the physicochemical properties of the formulated oil.

The obtained results show that straight adipates and sebacates of 2‐ethylhexanol and 3,5,5‐trimethylhexanol as well as oligomeric esters in which molecules are terminated with 2‐ethylhexyl group can be used as component of lubricating oils. The addition of these esters reduced the pour point by a few degrees in comparison with the tested base oil. The temperature fell below 40°C. The presence of esters significantly improved the viscosity index. A positive influence of esters on the lubricating properties of the formulated oil was also observed. On the contrary, dialkyl carbonates show too low boiling point, which is indicated by the high amount of volatile components, 19‐22 percent, in final product. Adipic and sebacic oligomers containing methoxyl groups in their structures proved to be immiscible with polyalphaolefins.

The achievement of this work is the synthesis of new oligomeric esters of dicarboxylic acids, which can be excellent additives for improving properties of synthetic oils. Further studies will be focused on the use of esters as components of engine oils. This requires real motor tests.