China 
Africa 
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Seasonal and Diel Changes in Particulate and Dissolved Organic Matter
Published in Roger S. Wotton, The Biology of Particles in Aquatic Systems, 2020
The influence of vertically migrating zooplankton on near-surface particulate composition is evident in the diel pattern of wax esters, derived almost entirely from zooplankton.256 Particulate wax ester flux collected in sediment traps at 10 to 15 m was twice as high during night than day. Total POC flux was also higher at night, by almost 50%. Triacylglycerols (products of both phytoplankton and zooplankton) showed no day-night differences. Submersible dives in the canyons south of Georges Bank revealed dense accumulations of the fecal pellets of the euphausiid Meganyctiphanes norvegica (300 to 845 μg C m−3) in the pycnocline at night.257 These sank at about 200 m d−1, accounting for a downward flux of 7 to 12 mg C m−2 d−1.
Vegetable Oil-Based Lubricant Additives
Published in Brajendra K. Sharma, Girma Biresaw, Environmentally Friendly and Biobased Lubricants, 2016
The extensive research for sulfurized sperm whale oil substitute has resulted in several patents. The preferred raw materials turned out to be vegetable oils alone or in combination with synthetic esters or wax ester such as jojoba oil. The largest use of sulfurized oils is in metalworking and grease applications, followed by industrial gear oils. However, sulfurized oils have limited thermal stability, which makes them undesirable for high-temperature applications, where fast decomposition of the EP additive is not desired. Corrosion toward yellow metals is another drawback of sulfurized compounds. At high temperatures, the active sulfur reacts with copper to form copper sulfide. Thus, improved thermal stability, low odor, low copper corrosion, and excellent solubility in base fluids are some of the challenges for sulfurized products for application in the new generation of industrial lubricants.
Biotechnological Intercession in Biofuel Production
Published in Rouf Ahmad Bhat, Moonisa Aslam Dervash, Khalid Rehman Hakeem, Khalid Zaffar Masoodi, Environmental Biotechnology, 2022
Wasia Showkat, Moonisa Aslam Dervash, Khalid Z. Masoodi, Javeed A. Mugloo, S. A. Gangoo, Saba Mir
In similar fashion, heterologous generation of bifunctional wax ester synthase/acyl-coenzyme A: diacylglycerol acyltransferase (WS/DGAT) from “A.calcoaceticus ADP1 in S. cerevisiae” can lead to manufacture of FAEEs and fatty acid isoamyl ester (Demirbaş, 2002). Investigations regarding the generation of microbial lipids have also been carried out in oleaginous yeasts, such as, “Rhodosporidium toruloides” (Demirbaş, 2002). Different genetic engineering strategies applied in microalgae for biodiesel application are shown in Figure 11.3.
Prediction of jatropha-algae biodiesel blend oil yield with the application of artificial neural networks technique
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2019
Sunil Kumar, Siddharth Jain, Harmesh Kumar
These properties of ANNs make them suitable for different types of problems and systems. Related to the biochemical processes, ANNs are applied for dynamic modeling and temperature control of a yeast fermentation bioreactor (Lawrynczuk 2008; Nagy 2007). Estimation of Lipozyme catalyzed the synthesis of wax ester from palm oil and oleyl alcohol (BAsri et al. 2007). The optimized parameters of the transesterification process developed using ANN with genetic algorithm (GA) modeling were as follows: reaction temperature 47°C, 6% w/w catalyst, reaction time of 68 h, and molar ratio of 10:1, which resulted in 94.6% Biofuel sustainability ordinance (BSO) FAME yield (Zeynab et al. 2017). The performance of ANN and response surface methodology (RSM) in the transesterification of yellow oleander oil to biodiesel and showed that ANN gave better results than RSM both in terms of data fitting and predictive ability (Betiku and Ajala 2014). The optimum conditions for transesterification with RSM was found to be for temperature, molar ratio, potassium hydroxide, and time were 64°C, 8 1.8wt%, and 20 min respectively by ultrasound power of 400 watt and with ANN temperature, molar ratio, potassium hydroxide, and time were 64°C, 8.3, 2wt%, and 26.5 min with ultrasound power of 370 watt (Baharak et al. 2016).Transesterification of Jatropha–algae oil was successfully performed and analyzed by both RSM and ANN tools. ANN and RSM-based Box-Behnken Design (BBD) was used to predict the model for the transesterification process. R2 values of the models from RSM and ANN were 0.9867 and 0.9976, respectively, which showed that ANN was more efficient than RSM (Sunil Kumar, Jain, and Kumar. 2017). Biodiesel yield from Ceiba pentandra seed oil was optimized with ant colony optimization combined with ANN to identify the optimal reaction parameters for bioethanol production from sorghum grains, resulting in maximum volumetric ethanol yield per unit sugars (Sebayang et al. 2017). The neurons in the ANN modeling are controlled by transfer and summing function. The most predominantly used transfer functions are Linear Transfer Function (purelin), Log-Sigmoid Transfer Function (logsig) and Tan-Sigmoid Transfer Function (tansig) (Das et al. 2015).