scholarly journals Laminaria digitata and Palmaria palmata Seaweeds as Natural Source of Catalysts for the Cycloaddition of CO2 to Epoxides

Molecules ◽  
2019 ◽  
Vol 24 (2) ◽  
pp. 269 ◽  
Author(s):  
James Comerford ◽  
Thomas Gray ◽  
Yann Lie ◽  
Duncan Macquarrie ◽  
Michael North ◽  
...  
Keyword(s):  
Amino Acids ◽  
Particle Size ◽  
Palmaria Palmata ◽  
Cyclic Carbonates ◽  
Laminaria Digitata ◽  
Subsequent Removal ◽  
Solvent Free Conditions ◽  
Maximum Conversion ◽  
Styrene Carbonate ◽  
Chloride Salts

Seaweed powder has been found to act as an effective catalyst for the fixation of CO2 into epoxides to generate cyclic carbonates under solvent free conditions. Model background reactions were performed using metal halides and amino acids typically found in common seaweeds which showed potassium iodide (KI) to be the most active. The efficacy of the seaweed catalysts kelp (Laminaria digitata) and dulse (Palmaria palmata) was probed based on particle size, showing that kelp possessed greater catalytic ability, achieving a maximum conversion and selectivity of 63.7% to styrene carbonate using a kelp loading of 80% by weight with respect to epoxide, 40 bar of CO2, 120 °C for 3 h. Maximizing selectivity was difficult due to the generation of diol side product from residual H2O found in kelp, along with a chlorinated by-product thought to form due to a high quantity of chloride salts in the seaweeds. Data showed there was loss of organic matter upon use of the kelp catalyst, likely due to the breakdown of organic compounds and their subsequent removal during product extraction. This was highlighted as the likely cause of loss of catalytic activity upon reuse of the Kelp catalyst.

Collecting amino acids in the Enceladus plume

2018 ◽  
Vol 18 (1) ◽  
pp. 47-59 ◽  
Author(s):  
Melissa Guzman ◽  
Ralph Lorenz ◽  
Dana Hurley ◽  
William Farrell ◽  
John Spencer ◽  
...  
Keyword(s):  
Amino Acids ◽  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Free Amino Acids ◽  
Free Amino ◽  
Deep Ocean ◽  
Mass Rate ◽  
Bubble Bursting ◽  
Deep Ocean Water

AbstractWe numerically model the dynamics of the Enceladus plume ice grains and define our nominal plume model as having a particle size distributionn(R) ~R−qwithq= 4 and a total particulate mass rate of 16 kg s−1. This mass rate is based on average plume brightness observed by Cassini across a range of orbital positions. The model predicts sample volumes of ~1600 µg for a 1 m2collector on a spacecraft making flybys at 20–60 km altitudes above the Enceladus surface. We develop two scenarios to predict the concentration of amino acids in the plume based on these assumed sample volumes. We specifically consider Glycine, Serine, α-Alanine, α-Aminoisobutyric acid and Isovaline. The first ‘abiotic’ model assumes that Enceladus has the composition of a comet and finds abundances between 2 × 10−6to 0.003 µg for dissolved free amino acids and 2 × 10−5to 0.3 µg for particulate amino acids. The second ‘biotic’ model assumes that the water of Enceladus's ocean has the same amino acid composition as the deep ocean water on Earth. We compute the expected captured mass of amino acids such as Glycine, Serine, and α-Alanine in the ‘biotic’ model to be between 1 × 10−5to 2 × 10−5µg for dissolved free amino acids and dissolved combined amino acids and about 0.0002 µg for particulate amino acids. Both models consider enhancements due to bubble bursting. Expected captured mass of amino acids is calculated for a 1 m2collector on a spacecraft making flybys with a closest approach of 20 km during mean plume activity for the given nominal particle size distribution.

Efficient CO2 fixation into cyclic carbonates catalyzed by NNO-scorpionate zinc complexes

2019 ◽  
Vol 48 (28) ◽  
pp. 10733-10742 ◽  
Author(s):  
Sonia Sobrino ◽  
Marta Navarro ◽  
Juan Fernández-Baeza ◽  
Luis F. Sánchez-Barba ◽  
Andrés Garcés ◽  
...  
Keyword(s):  
Co2 Fixation ◽  
Functional Group ◽  
Zinc Complexes ◽  
Solvent Free ◽  
Cyclic Carbonates ◽  
Solvent Free Conditions

Chiral bifunctional and bicomponent NNO-scorpionate zinc-based catalysts have been developed for the fixation of CO2 into cyclic carbonates with broad substrate scope and functional group tolerance under mild and solvent-free conditions.

scholarly journals Keratin Hydrolysates Extracted from Sheep Wool with Potential Use as Organic Fertilizer

2020 ◽  
Vol 20 (3) ◽  
pp. 267-276
Author(s):  
Mariana Daniela Berechet ◽  
Demetra Simion ◽  
Maria Stanca ◽  
Cosmin-Andrei Alexe ◽  
Ciprian Chelaru ◽  
...  
Keyword(s):  
Amino Acids ◽  
Particle Size ◽  
Organic Fertilizer ◽  
Control Sample ◽  
Reaction Medium ◽  
Organic Fertilizers ◽  
Particle Measurements ◽  
Potential Use ◽  
Wheat Seeds ◽  
Sheep Wool

Keratin hydrolysates were obtained from sheep wool by alkaline hydrolysis at different concentrations of KOH (3%, 5% and 8%) and temperatures (75°C, 85°C, 95°C and 99°C) of the reaction medium. The protein content of the keratin extracts was between 65.54% and 87.10%. Particle measurements showed a decrease in particle size with the increase of concentration and temperature of the reaction medium. The ATR-FTIR spectra revealed specific bands to proteins and sulfur originated from keratin amino acids. The keratin hydrolysate type KerK895 was further investigated as organic fertilizer for two types of wheat seeds. The results showed that the use of 5% KerK895 led to the increase of the wheat stems lengths by 10.7% for Mirastar wheat and 18.3% for Tamino wheat, respectively, compared to control sample. Keratin hydrolysates are promising biopolymers as organic fertilizers in agriculture applications.

scholarly journals Amino acids digestibility of pelleted microparticle protein of fish meal and soybean meal in broiler chickens

2018 ◽  
Vol 43 (2) ◽  
pp. 169 ◽  
Author(s):  
N. Suthama ◽  
P. J. Wibawa
Keyword(s):  
Amino Acids ◽  
Particle Size ◽  
Soybean Meal ◽  
Broiler Chickens ◽  
Fish Meal ◽  
Coconut Oil ◽  
Intact Protein ◽  
Calcium Retention ◽  
Randomized Design ◽  
Completely Randomized Design

Commom protein sources for poultry, fish meal and soybean meal, were ground to obtain reduced particle size. The particle was then dissolved in distilled water (1 : 4 w/v), and added with 2 mL virgin coconut oil for every 500 mL solution prior to ultrasound transducer (ultrasonic bath) treatment to obtain protein microparticle. Reducing particle size is one possible way to increase protein utilization.180 birds were used for forced feeding and 10 other birds were plotted for endogenous correction, when they were one month and a half old. Microparticle protein of both ingredients were tested separately in either mash or pelleted forms and compared to intact protein. Completely randomized design with 3 treatments (intact, mash, and pellet) and 6 replications (10 bidrs each) was arranged for the respective ingredient. Protein and essential amino acid digestibilities, and calcium retention were the parameters measured. Analysis of variance continued to Duncan test were applied to statistically evaluate the data. Pelleted microparticle protein of fish meal and soybean meal, respectively, resulted in significantly (P<0.05) highest protein and amino acids digestibilities, and Ca retention although lower disgestibility of fewer amino acids was found in mash form. In conclusion, pelleted form of microparticle protein of either fish meal or soybean meal improve protein and mostly amino acids digestibilities, and calcium retention in broiler. 

Amino acids/superbases as eco-friendly catalyst system for the synthesis of cyclic carbonates under metal-free and halide-free conditions

2018 ◽  
Vol 48 (8) ◽  
pp. 876-886 ◽  
Author(s):  
Yaqiong Qi ◽  
Weiguo Cheng ◽  
Fei Xu ◽  
Shengli Chen ◽  
Suojiang Zhang
Keyword(s):  
Amino Acids ◽  
Catalyst System ◽  
Cyclic Carbonates ◽  
Metal Free
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