Analyzing and optimizing the carbon utilization and lipid yield at different light intensities for Scenedesmus arcuatus

2021 ◽  
Vol 25 (11) ◽  
pp. 1-10
Author(s):  
K. Vasumathi ◽  
Raja Vadivu G. Nadana ◽  
E.M. Nithiya ◽  
K. Sundar ◽  
M. Premalatha
Keyword(s):  
Light Intensity ◽  
Large Scale ◽  
Biomass Yield ◽  
Osmotic Shock ◽  
High Light Intensity ◽  
Carbon Utilization ◽  
Lipid Yield ◽  
The Face ◽  
Photosynthetic Microorganism ◽  
Pre Treatment

Microalgae, the photosynthetic microorganism growing abundantly in marine and aquatic ecosystems, are potential source for biological sequestration of CO2. The carbon uptake differs in the presence of other nutrients, light intensity etc. The biomass yield of Scenedesmus arcuatus var capitatus was studied based on the Face Centred Central Composite design (FCCD) of Response Surface Methodology (RSM) for nitrate, phosphate and carbonate under different conditions (laboratory, room and sunlight conditions). Various pre-treatments (osmotic shock, autoclaving, microwave and ultrasonication) were employed to find the best method for maximum lipid yield. The biomass yield reached a maximum of 1 g/L under sunlight conditions of nitrate concentration 500 ppm and carbonate 2000 ppm. The laboratory conditions resulted in a biomass yield of 0.59 g/L at 500 ppm nitrate, 1000 ppm carbonate and 250 ppm phosphate. Under room conditions, the yield was very low (0.11 g/L). Osmotic shock resulted in higher lipid yield than the other pre-treatment methods. The ability of Scenedesmus arcuatus to uptake high carbon under sunlight conditions and to adapt to high light intensity and fluctuations in light intensity concludes that this species is suitable for large-scale open pond cultivation for CO2 sequestration and production of metabolites.

scholarly journals Light Intensity and Nitrogen Concentration Impact on the Biomass and Phycoerythrin Production by Porphyridium purpureum

Marine Drugs ◽  
2019 ◽  
Vol 17 (8) ◽  
pp. 460 ◽  
Author(s):  
Juan Eduardo Sosa-Hernández ◽  
Laura Isabel Rodas-Zuluaga ◽  
Carlos Castillo-Zacarías ◽  
Magdalena Rostro-Alanís ◽  
Reynaldo de la Cruz ◽  
...  
Keyword(s):  
Light Intensity ◽  
Biomass Yield ◽  
Nitrogen Concentration ◽  
Biomass Productivity ◽  
Dry Weight ◽  
High Light Intensity ◽  
High Biomass ◽  
Porphyridium Purpureum ◽  
Nitrogen Concentrations ◽  
Low Nitrogen

Several factors have the potential to influence microalgae growth. In the present study, nitrogen concentration and light intensity were evaluated in order to obtain high biomass production and high phycoerythrin accumulation from Porphyridium purpureum. The range of nitrogen concentrations evaluated in the culture medium was 0.075–0.450 g L−1 and light intensities ranged between 30 and 100 μmol m−2 s−1. Surprisingly, low nitrogen concentration and high light intensity resulted in high biomass yield and phycoerythrin accumulation. Thus, the best biomass productivity (0.386 g L−1 d−1) and biomass yield (5.403 g L−1) were achieved with NaNO3 at 0.075 g L−1 and 100 μmol m−2 s−1. In addition, phycoerythrin production was improved to obtain a concentration of 14.66 mg L−1 (2.71 mg g−1 of phycoerythrin over dry weight). The results of the present study indicate that it is possible to significantly improve biomass and pigment production in Porphyridium purpureum by limiting nitrogen concentration and light intensity.

scholarly journals A 3D-Printed Open Access Photoreactor Designed for Versatile Applications in Photoredox- & Photoelectrochemical Synthesis

2020 ◽  
Author(s):  
Florian Schiel ◽  
Christoph Peinsipp ◽  
Stefan Kornigg ◽  
Dietrich Böse
Keyword(s):  
Light Intensity ◽  
Large Scale ◽  
High Light Intensity ◽  
Photochemical Reactions ◽  
Catalyst Loading ◽  
Fast Reaction ◽  
Thermoelectric Coolers ◽  
Practical Design ◽  
3D Printed ◽  
Reaction Vessels

Most published photochemical reactions are still not performed under standardized conditions. It is well known that the control of light intensity, the exact reaction temperature and other parameters are crucial for the success of a photochemical reaction. However, for most reactions reported in the literature, these parameters are not precisely controlled and recorded. As a result, the reproduction of these reactions is difficult and the progress in the field of photoredox chemistry is hampered by this limitation. To address this problem, a 3D-printed photoreactor was designed which can be easily replicated with a small number of inexpensive and easily available components. Equipped with thermoelectric coolers, the reactor can access and precisely control the temperature in the range of -17 °C to 80 °C, while reactions under high-intensity irradiation are performed with LED lamps from Kessil or HepatoChem. The practical design of the vial holder allows a versatile use of different reaction vessels - in addition to fast reaction opMost published photochemical reactions are still not performed under standardized conditions. It is well known that the control of light intensity, the exact reaction temperature and other parameters are crucial for the success of a photochemical reaction. However, for most reactions reported in the literature, these parameters are not precisely controlled and recorded. As a result, the reproduction of these reactions is difficult and the progress in the field of photoredox chemistry is hampered by this limitation. To address this problem, a 3D-printed photoreactor was designed which can be easily replicated with a small number of inexpensive and easily available components. Equipped with thermoelectric coolers, the reactor can access and precisely control the temperature in the range of -17 °C to 80 °C, while reactions under high-intensity irradiation are performed with LED lamps from Kessil or HepatoChem. The practical design of the vial holder allows a versatile use of different reaction vessels - in addition to fast reaction optimization with up to eight vials simultaneously, upscaling in batch and flow is easily possible. Due to the high light intensity, the catalyst loading can be reduced to 0.1 mol% for large-scale reactions. The flexibility of the vial holder is demonstrated by combining IKA’s ElectraSyn 2.0 with the photoreactor to perform photoelectrochemical reactions in a reproducible manner.timization with up to eight vials simultaneously, upscaling in batch and flow is easily possible. Due to the high light intensity, the catalyst loading can be reduced to 0.1 mol% for large-scale reactions. The flexibility of the vial holder is demonstrated by combining IKA’s ElectraSyn 2.0 with the photoreactor to perform photoelectrochemical reactions in a reproducible manner.

scholarly journals A 3D-Printed Open Access Photoreactor Designed for Versatile Applications in Photoredox- & Photoelectrochemical Synthesis

2020 ◽  
Author(s):  
Florian Schiel ◽  
Christoph Peinsipp ◽  
Stefan Kornigg ◽  
Dietrich Böse
Keyword(s):  
Light Intensity ◽  
Large Scale ◽  
High Light Intensity ◽  
Photochemical Reactions ◽  
Catalyst Loading ◽  
Fast Reaction ◽  
Thermoelectric Coolers ◽  
Reaction Optimization ◽  
3D Printed ◽  
Reaction Vessels

Most published photochemical reactions are still not performed under standardized conditions. It is well known that the control of light intensity, the exact reaction temperature and other parameters are crucial for the success of a photochemical reaction. However, for most reactions reported in the literature, these parameters are not precisely controlled and recorded. As a result, the reproduction of these reactions is difficult and the progress in the field of photoredox chemistry is hampered by this limitation. To address this problem, a 3D-printed photoreactor was designed which can be easily replicated with a small number of inexpensive and easily available components. Equipped with thermoelectric coolers, the reactor can access and precisely control the temperature in the range of -17 °C to 80 °C, while reactions under high-intensity irradiation are performed with LED lamps from Kessil or HepatoChem. The practical design of the vial holder allows a versatile use of different reaction vessels - in addition to fast reaction optimization with up to eight vials simultaneously, upscaling in batch and flow is easily possible. Due to the high light intensity, the catalyst loading can be reduced to 0.1 mol% for large-scale reactions. The flexibility of the vial holder is demonstrated by combining IKA’s ElectraSyn 2.0 with the photoreactor to perform photoelectrochemical reactions in a reproducible manner.<br>

scholarly journals A 3D-Printed Open Access Photoreactor Designed for Versatile Applications in Photoredox- & Photoelectrochemical Synthesis

2020 ◽  
Author(s):  
Florian Schiel ◽  
Christoph Peinsipp ◽  
Stefan Kornigg ◽  
Dietrich Böse
Keyword(s):  
Light Intensity ◽  
Large Scale ◽  
High Light Intensity ◽  
Photochemical Reactions ◽  
Catalyst Loading ◽  
Fast Reaction ◽  
Thermoelectric Coolers ◽  
Reaction Optimization ◽  
3D Printed ◽  
Reaction Vessels

Most published photochemical reactions are still not performed under standardized conditions. It is well known that the control of light intensity, the exact reaction temperature and other parameters are crucial for the success of a photochemical reaction. However, for most reactions reported in the literature, these parameters are not precisely controlled and recorded. As a result, the reproduction of these reactions is difficult and the progress in the field of photoredox chemistry is hampered by this limitation. To address this problem, a 3D-printed photoreactor was designed which can be easily replicated with a small number of inexpensive and easily available components. Equipped with thermoelectric coolers, the reactor can access and precisely control the temperature in the range of -17 °C to 80 °C, while reactions under high-intensity irradiation are performed with LED lamps from Kessil or HepatoChem. The practical design of the vial holder allows a versatile use of different reaction vessels - in addition to fast reaction optimization with up to eight vials simultaneously, upscaling in batch and flow is easily possible. Due to the high light intensity, the catalyst loading can be reduced to 0.1 mol% for large-scale reactions. The flexibility of the vial holder is demonstrated by combining IKA’s ElectraSyn 2.0 with the photoreactor to perform photoelectrochemical reactions in a reproducible manner.<br>

Characteristics of Photosynthesis in Different Wheat Cultivars under High Light Intensity and High Temperature Stresses

2009 ◽  
Vol 34 (12) ◽  
pp. 2196-2201 ◽  
Author(s):  
Xue-Li QI ◽  
Lin HU ◽  
Hai-Bin DONG ◽  
Lei ZHANG ◽  
Gen-Song WANG ◽  
...  
Keyword(s):  
High Temperature ◽  
Light Intensity ◽  
High Light Intensity ◽  
High Light ◽  
Wheat Cultivars ◽  
Temperature Stresses

Reuse of Wastewaters in Agriculture by Means of Sprinkler Irrigation on a Farmland Area of 3000 ha – Large Scale Experience in Germany

1986 ◽  
Vol 18 (9) ◽  
pp. 163-173
Author(s):  
R. Boll ◽  
R. Kayser
Keyword(s):  
Large Scale ◽  
Treatment Process ◽  
Treatment Plant ◽  
Sprinkler Irrigation ◽  
Paper Briefly ◽  
Treatment Results ◽  
Sewage Farm ◽  
Western Germany ◽  
Pre Treatment ◽  
Main Components

The Braunschweig wastewater land treatment system as the largest in Western Germany serves a population of about 270.000 and has an annual flow of around 22 Mio m3. The whole treatment process consists of three main components : a pre-treatment plant as an activated sludge process, a sprinkler irrigation area of 3.000 ha of farmland and an old sewage farm of 200 ha with surface flooding. This paper briefly summarizes the experiences with management and operation of the system, the treatment results with reference to environmental impact, development of agriculture and some financial aspects.

Use of lime for the upgrading of existing wastewater treatment systems

1994 ◽  
Vol 29 (12) ◽  
pp. 279-282 ◽  
Author(s):  
C. Güldner ◽  
W. Hegemann ◽  
N. Peschen ◽  
K. Sölter
Keyword(s):  
Large Scale ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Chemical Precipitation ◽  
Fatty Acid Production ◽  
German States ◽  
Lime Solution ◽  
First Results ◽  
Pre Treatment

The integration of the chemical precipitation unit which would inject a lime solution into a series of mechanical-biological processes, including nitrification/denitrification, and the sludge treatment are the subject of this project. The essential target is the large-scale reconstruction of a mechanical-biological sewage treatment plant with insufficient cleaning performance in the new German states and the adjustment of the precipitation stage to the unsteady inflow of sewage. First results indicate that the pre-treatment performance could be improved by ≅ 20% and the discharge of concentrations of COD, BOD, N and P could be reduced and homogenized. In addition, experiments on hydrolysis and acidifiability of the pre-treatment sludge have been carried out on a laboratory level with the object of making sources of carbon readily available for denitrification. In the course of the experiment, inhibition of fatty acid production by calcareous primary sludge could not be detected. The characteristics of the sludge, such as draining and thickening were considerably improved by the adding of lime.

Ban Ki-moon, 2007–2016

2018 ◽  
Author(s):  
Richard Gowan
Keyword(s):  
United States ◽  
Decision Making ◽  
Security Council ◽  
Large Scale ◽  
Central African Republic ◽  
The United States ◽  
Cautious Approach ◽  
Peacekeeping Operations ◽  
Council Decision ◽  
The Face

During Ban Ki-moon’s tenure, the Security Council was shaken by P5 divisions over Kosovo, Georgia, Libya, Syria, and Ukraine. Yet it also continued to mandate and sustain large-scale peacekeeping operations in Africa, placing major burdens on the UN Secretariat. The chapter will argue that Ban initially took a cautious approach to controversies with the Council, and earned a reputation for excessive passivity in the face of crisis and deference to the United States. The second half of the chapter suggests that Ban shifted to a more activist pressure as his tenure went on, pressing the Council to act in cases including Côte d’Ivoire, Libya, and Syria. The chapter will argue that Ban had only a marginal impact on Council decision-making, even though he made a creditable effort to speak truth to power over cases such as the Central African Republic (CAR), challenging Council members to live up to their responsibilities.

scholarly journals Reframing refugee crisis: A “European crisis of migration” or a “crisis of protection”?

2021 ◽  
pp. 239965442198970
Author(s):  
Maissaa Almustafa
Keyword(s):  
Large Scale ◽  
Global South ◽  
Global Media ◽  
Developing Regions ◽  
International Protection ◽  
High Commissioner ◽  
The Face ◽  
Global North ◽  
Displaced People ◽  
Resettlement Programs

The end of 2015 witnessed a global record in the number of forcibly displaced people fleeing because of wars and persecution. The unprecedented total of 65.3 million displaced individuals, out of which 21.3 million were refugees, was the highest number that the United Nations High Commissioner for Refugees (UNHCR) has recorded since its establishment in 1950. During the same year and in the face of this large-scale crisis, only 107,100 refugees were admitted for resettlement through official resettlement programs, whereas 3.2 million people applied for asylum globally. And in spite of the fact that the majority of the world refugees are hosted in ten developing regions, the dominant narrative in the global media was about the “unauthorized” arrival of more than one million asylum seekers in Europe by sea during 2015. This paper argues that the unexpected nature of refugees’ arrivals has proven that refugees were supposed to be contained in their camps in the Global South, deterred from reaching the territories of the Global North, represented here by Europe. Thus, the paper proposes that these arrivals are rather reflections of a crisis of protection that developed in the Global South where containment and deterrence strategies against refugees from the Global South exacerbate their inhumane displacement conditions in home regions. In the same context, the paper discusses how international protection structures have been reconstructed to serve the same goals of containment and deterrence, with the ultimate aim of putting people ‘back in place’ with minimal access to protection and rights.

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