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Carbon capture and storage with lipid production in integrated system of aqueous ammonia with marine mutant Synechococcus PCC 7002 IIUM01
No full textCarbon capture and storage (CCS) involves capturing, transporting and storing CO2 geologically underground permanently. Carbon capture using solvent such as amine and aqueous ammonia has been extensively studied by many researchers. However, this capture technology for CCS scheme is costly. As an alternative, CO2 emission can be cost-effectively captured and stored by utilizing the well-understood natural photosynthetic process of marine cyanobacteria. In contrast, the capturing process using cyanobacteria is very slow compared to the chemical absorption mentioned prior. Hence, this study aimed to investigate carbon capturing and storing process using integrated aqueous ammonia and mutated marine cyanobacteria (Synechococcus PCC 7002 IIUM01). The conditions that can maximize CO2 reduction under various conditionsCO2 flow rate (Lpm), absorption temperature (?C) and aqueous ammonia concentrations (% (w/v)) were to be identified. The effectiveness of the mutant cyanobacteria was quantified by measuring the cell concentration, percentage reduction in CO2 concentration and lipid content. Synechococcus PCC 7002 IIUM01 showed it robustness by growing in aqueous ammonia solution at the concentration of 0.5 to 1% (w/v) at which the parent strain was not able to tolerate. The best conditions in maximizing CO2 capture and storage while sustaining growth optimally and being a potential biofuel source was observed at 0.5 Lpm of 15% CO2 gas flow rate, 0.75% (w/v) of ammonia concentration and 33?C of absorption temperature. At this specified condition, around 68% of CO2 removal was achieved with 9% (w/w) yield of lipid and more than 13% (w/v) of cell concentration obtained
Interactive effect of temperature, pH and light intensity on biodesalination of seawater by synechococcus sp. PCC 7002 and on the cyanobacteria growth
No full textDesalination allows to pipe viable water supply from ocean, the largest water resource, as potable water for drink and daily usage. The technology such as thermal distillation and membrane separation technology requires intense energy source. Almost all desalination plants using fossil fuel as their primary energy source, which leads to many challenges. Marine-euryhaline Synechococcus sp. strain PCC 7002, on the other hand, is one of the potential cyanobacteria that may contribute to the development and advancement in water treatment field. These cyanobacteria are able to generate a huge amount of biomass and producing fresh water (low-salt saline water). Thus, this leads the study to investigate the influence of process parameters on biodesalination by Synechococcus sp. PCC 7002 associate to growth rate of the cyanobacteria. The results showed that temperature, light intensity and pH play important role in sodium reduction. More than 50% of salinity reduction was obtained at optimum condition. Interactive effects between selected factors concluded that higher salinity removal was observed at temperature of 36oC with the pH of 10 and light intensity of 3500 lux. However, the growth is contrast to biodesalination. Interaction effect between temperature-pH, suggested that the growth prefer near neutral condition regardless of the temperature. When temperature interacts with light intensity, inverse relation of these two factors resulted of higher growth rates. Further study is required to understand biodesalination by Synechococcus sp. and its growth. Nevertheless, the study has shown that biodesalination by Synechococcus sp. has the potential in biodesallination process and integration with current technology for potable water source can be further investigated
The effect of CO2 concentrations and the injection strategy on Synechococcus sp. PCC7002 culture
No full textPhotosynthetic microorganism such as cyanobacteria emerge attractive due to its diverse potential uses in the biotechnology
field. It is also useful for CO2
sequestration and biofuel production. However different CO2 concentrations supplied to the
culture affect cell growth and lipid production in different ways. This paper focuses on the influences of CO2
concentrations (i.e.
15%(v/v) to 30% (v/v)), which was supplied for 30 minutes every day (i.e. total of 7 days of experiment duration) to the culture
system, on the growth of Synechococccus sp. (PCC 7002 strain), total lipid production, culture pH and CO2
removal. The results
showed that the highest growth and total lipid were obtained when the culture was supplied with 15%(v/v) and 30%(v/v) of
CO2
, respectively. The CO2
removal was decreasing when the concentration was at 30%(v/v). Finally, the pH of cultures reduced
as the CO2
concentration increased
Chlorella vulgarislogistic growth kinetics model in high concentrations of aqueous ammonia
No full textAPPLICATION OF PLACKETT-BURMAN DESIGN FOR SCREENING OF PARAMETERS FOR THE PRODUCTION OF TETRATHIONATE HYDROLASE BY THIOBACILLUS FERROOXIDANS
No full textAbstract Enzymatic devulcanisation is one of the methods of recycling waste rubber tire. Among all devulcanised methods that are introduced, biological method is a safer choice because it does not include any harmful or toxic chemicals, and is normally not energy intensive. The process deems more efficient and less expensive compared to various other devulcanisation methods. This method was done by exposing a surface of a vulcanised rubber piece to at least one enzyme, secreted from chemolithoautotrophic iron-and sulphur-oxidising bacterium to break the sulphur bonds in the vulcanised rubber structure, rendering it more acceptable to be recycled. By applying the enzymatic devulcanisation, it is hoped that the amount of demand of raw rubber can be reduced and at the same time helps to reduce the solid waste disposal problem. In this study, the process parameters that affect the tetrathionate hydrolase activity secreted from Thiobacillus ferrooxidans was screened using PlackettBurman design (PBD). Among the various variables, results showed initial pH, agitation rate, temperature of incubation, inoculum size and calcium chloride concentration were determined as the most influential variables on tetrathionate hydrolase production
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Preliminary optimization of process conditions for biohydrogen production from sago wastewater
No full textVariations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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