Heat Transfer Enhancement by Hybrid Nano Additives-Graphene Nanoplatelets/Cellulose Nanocrystal for the Automobile Cooling System (Radiator).

A radiator is used to remove a portion of the heat generated by a vehicle engine. It is challenging to efficiently maintain the heat transfer in an automotive cooling system even though both internal and external systems need enough time to keep pace with catching up with evolving engine technology advancements. The effectiveness of a unique hybrid's heat transfer nanofluid was investigated in this study. The hybrid nanofluid was mainly composed of graphene nanoplatelets (GnP), and cellulose nanocrystals (CNC) nanoparticles suspended in a 40:60 ratio of distilled water and ethylene glycol. A counterflow radiator equipped with a test rig setup was used to evaluate the hybrid nano fluid's thermal performance. According to the findings, the proposed GNP/CNC hybrid nanofluid performs better in relation to improving the efficiency of heat transfer of a vehicle radiator. The suggested hybrid nanofluid enhanced convective heat transfer coefficient by 51.91%, overall heat transfer coefficient by 46.72%, and pressure drop by 34.06% with respect to distilled water base fluid. Additionally, the radiator could reach a better CHTC with 0.01% hybrid nanofluid in the optimized radiator tube by the size reduction assessment using computational fluid analysis. In addition to downsizing the radiator tube and increasing cooling capacity over typical coolants, the radiator takes up less space and helps to lower the weight of a vehicle engine. As a result, the suggested unique hybrid graphene nanoplatelets/cellulose nanocrystal-based nanofluids perform better in heat transfer enhancement in automobiles.

Recent Progress in Harvest and Recovery Techniques of Mammalian and Algae Cells for Industries.

In our modern world, biotechnology products play important roles not only in our health and culture, but also various industries such as food, agriculture, sewage treatment, biofuels, nutraceuticals, and pharmaceuticals. Rapid technological advances in biotechnology over the last few decades have allowed industrial integration of mammalian cells (like the Chinese hamster ovary cells) and algae cells in pharmaceutical and biofuel industries to produce commercial products and valuable biomolecules. However, the cost of cell harvest and recovery can become expensive depending on the harvesting technique, degree of purification, and intended use of the end-products. This has led to numerous research in exploring and developing efficient harvesting techniques. Therefore, in this review, the popular harvesting techniques and their recent applications will be discussed.

Exploring the potency of integrating semi-batch operation into lipid yield performance of Chlamydomonas sp. Tai-03.

Third generation biofuels, also known as microalgal biofuels, are promising alternatives to fossil fuels. One attractive option is microalgal biodiesel as a replacement for diesel fuel. Chlamydomonas sp. Tai-03 was previously optimized for maximal lipid production for biodiesel generation, achieving biomass growth and productivity of 3.48 ±â€¯0.04 g/L and 0.43 ±â€¯0.01 g/L/d, with lipid content and productivity of 28.6 ±â€¯1.41% and 124.1 ±â€¯7.57 mg/L/d. In this study, further optimization using 5% CO2 concentration and semi-batch operation with 25% medium replacement ratio, enhanced the biomass growth and productivity to 4.15 ±â€¯0.12 g/L and 1.23 ±â€¯0.02 g/L/d, with lipid content and productivity of 19.4 ±â€¯2.0% and 239.6 ±â€¯24.8 mg/L/d. The major fatty acid methyl esters (FAMEs) were palmitic acid (C16:0), oleic acid (C18:1), and linoleic acid (C18:2). These short-chain FAMEs combined with high growth make Chlamydomonas sp. Tai-03 a suitable candidate for biodiesel synthesis.

Proteins recovery from wet microalgae using liquid biphasic flotation (LBF).

In this work, the extraction of microalgal protein from wet Chlorella sorokiniana species using alcohol/salt liquid biphasic flotation (LBF) with the aid of ultrasonication for cell rupturing was proposed. The effect of varying crude feedstock concentration, flotation time, salt type, salt concentration, alcohol type, alcohol concentration, initial volumes of salt and alcohol were investigated. After the optimization process, the highest proportion of protein recovered in the top phase was achieved with 250g/L ammonium sulphate, 60% (v/v) 2-propanol, 1.0VR,initial, 20g/L crude biomass load, 4mm3/min air flowrate and 10min of flotation time. The recycling of phase components was introduced to minimize the use of alcohol and salt in the corresponding LBF. It was demonstrated that top phase (alcohol) recycling can achieve increasing performance for three consecutive recycling runs. Under optimized process conditions, the proportion of protein recovered in the top phase was 88.86% for the third recycle run.

Improving protein production of indigenous microalga Chlorella vulgaris FSP-E by photobioreactor design and cultivation strategies.

Fish meal is currently the major protein source for commercial aquaculture feed. Due to its unstable supply and increasing price, fish meal is becoming more expensive and its availability is expected to face significant challenges in the near future. Therefore, feasible alternatives to fish meal are urgently required. Microalgae have been recognized as the most promising candidates to replace fish meal because the protein composition of microalgae is similar to fish meal and the supply of microalgae-based proteins is sustainable. In this study, an indigenous microalga (Chlorella vulgaris FSP-E) with high protein content was selected, and its feasibility as an aquaculture protein source was explored. An innovative photobioreactor (PBR) utilizing cold cathode fluorescent lamps as an internal light source was designed to cultivate the FSP-E strain for protein production. This PBR could achieve a maximum biomass and protein productivity of 699 and 365 mg/L/day, respectively, under an optimum urea and iron concentration of 12.4 mM and 90 µM, respectively. In addition, amino acid analysis of the microalgal protein showed that up to 70% of the proteins in this microalgal strain consist of indispensable amino acids. Thus, C. vulgaris FSP-E appears to be a viable alternative protein source for the aquaculture industry.

Novel approaches of producing bioenergies from microalgae: A recent review.

Microalgae have caught the world's attention for its potential to solve one of the world's most pressing issues-sustainable green energy. Compared to biofuels supplied by oil palm, rapeseed, soybean and sugar cane, microalgae alone can be manipulated to generate larger amounts of biodiesel, bioethanol, biohydrogen and biomass in a shorter time. Apart from higher productivity, microalgae can also grow using brackish water on non-arable land, greatly reducing the competition with food and cash crops. Hence, numerous efforts have been put into the commercialisation of microalgae-derived biofuel by both the government and private bodies. This paper serves to review conventional and novel methods for microalgae culture and biomass harvest, as well as recent developments in techniques for microalgal biofuel production.

Novel lipase purification methods - a review of the latest developments.

Microbial lipases are popular biocatalysts due to their ability to catalyse diverse reactions such as hydrolysis, esterification, and acidolysis. Lipases function efficiently on various substrates in aqueous and non-aqueous media. Lipases are chemo-, regio-, and enantio-specific, and are useful in various industries, including those manufacturing food, detergents, and pharmaceuticals. A large number of lipases from fungal and bacterial sources have been isolated and purified to homogeneity. This success is attributed to the development of both conventional and novel purification techniques. This review highlights the use of these techniques in lipase purification, including conventional techniques such as: (i) ammonium sulphate fractionation; (ii) ion-exchange; (iii) gel filtration and affinity chromatography; as well as novel techniques such as (iv) reverse micellar system; (v) membrane processes; (vi) immunopurification; (vi) aqueous two-phase system; and (vii) aqueous two-phase floatation. A summary of the purification schemes for various bacterial and fungal lipases are also provided.