scholarly journals Chitosan Adsorbent Derivatives for Pharmaceuticals Removal from Effluents: A Review

Macromol ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 130-154
Author(s):  
Efstathios V. Liakos ◽  
Maria Lazaridou ◽  
Georgia Michailidou ◽  
Ioanna Koumentakou ◽  
Dimitra A. Lambropoulou ◽  
...  
Keyword(s):  
Emerging Contaminants ◽  
Low Cost ◽  
Value Added ◽  
Ph Effects ◽  
Hydroxyl Groups ◽  
Research Papers ◽  
Natural Polysaccharide ◽  
Best Fitting ◽  
Isotherm And Kinetic Models ◽  
Published Research

Chitin is mentioned as the second most abundant and important natural biopolymer in worldwide scale. The main sources for the extraction and exploitation of this natural polysaccharide polymer are crabs and shrimps. Chitosan (poly-β-(1 → 4)-2-amino-2-deoxy-d-glucose) is the most important derivative of chitin and can be used in a wide variety of applications including cosmetics, pharmaceutical and biomedical applications, food, etc., giving this substance high value-added applications. Moreover, chitosan has applications in adsorption because it contains amino and hydroxyl groups in its molecules, and can thus contribute to many possible adsorption interactions between chitosan and pollutants (pharmaceuticals/drugs, metals, phenols, pesticides, etc.). However, it must be noted that one of the most important techniques of decontamination is considered to be adsorption because it is simple, low-cost, and fast. This review emphasizes on recently published research papers (2013–2021) and briefly describes the chemical modifications of chitosan (grafting, cross-linking, etc.), for the adsorption of a variety of emerging contaminants from aqueous solutions, and characterization results. Finally, tables are depicted from selected chitosan synthetic routes and the pH effects are discussed, along with the best-fitting isotherm and kinetic models.

scholarly journals Adsorption of Uranium, Mercury, and Rare Earth Elements from Aqueous Solutions onto Magnetic Chitosan Adsorbents: A Review

Polymers ◽  
2021 ◽  
Vol 13 (18) ◽  
pp. 3137
Author(s):  
Georgia Michailidou ◽  
Ioanna Koumentakou ◽  
Efstathios V. Liakos ◽  
Maria Lazaridou ◽  
Dimitra A. Lambropoulou ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Aqueous Solutions ◽  
Low Cost ◽  
Kinetic Equations ◽  
Value Added ◽  
Hydroxyl Groups ◽  
Adsorption Mechanisms ◽  
Natural Polysaccharide ◽  
Effects Of Ph

The compound of chitin is the second most important and abundant natural biopolymer in the world. The main extraction and exploitation sources of this natural polysaccharide polymer are mainly crustaceans species, such as shrimps and crabs. Chitosan (CS) (poly-β-(1 → 4)-2-amino-2-deoxy-d-glucose) can be derived from chitin and can be mentioned as a compound that has high value-added applications due to its wide variety of uses, including pharmaceutical, biomedical, and cosmetics applications, food etc. Furthermore, chitosan is a biopolymer that can be used for adsorption applications because it contains amino and hydroxyl groups in its chemical structure (molecules), resulting in possible interactions of adsorption between chitosan and pollutants (uranium, mercury, rare earth elements (REEs), phenols, etc.). However, adsorption is a very effective, fast, simple, and low-cost process. This review article places emphasis on recent demonstrated research papers (2014–2020) where the chemical modifications of CS are explained briefly (grafting, cross-linking etc.) for the uptake of uranium, mercury, and REEs in synthesized aqueous solutions. Finally, figures and tables from selected synthetic routes of CS are presented and the effects of pH and the best mathematical fitting of isotherm and kinetic equations are discussed. In addition, the adsorption mechanisms are discussed.

Investigation of solution techniques of unit commitment problems: A review

2021 ◽  
pp. 0309524X2199244
Author(s):  
Vineet Kumar ◽  
Ram Naresh ◽  
Amita Singh
Keyword(s):  
Power Systems ◽  
Planning Process ◽  
Unit Commitment ◽  
Operational Planning ◽  
Recent Past ◽  
Research Papers ◽  
Start Up ◽  
Subsequent Step ◽  
Commitment Problems ◽  
Published Research

The Unit Commitment (UC) is a significant act of optimization in day-to-day operational planning of modern power systems. After load forecasting, UC is the subsequent step in the planning process. The electric utilities decide in advance which units are to start-up, when to connect them to the network, the sequence in which the generating units should be shut down and for how long. In view of the above, this paper attempts on presenting a thorough and precise review of the recent approaches applied in optimizing UC problems, incorporating both stochastic and deterministic loads, based on various peer reviewed published research papers of reputed journals. It emphasizes on non-conventional energy and distributed power generating systems along with deregulated and regulated environment. Along with an overview, a comprehensive analysis of the UC algorithms reported in the recent past since 2015 has been discussed for the assistance of new researchers concerned with this domain.

scholarly journals Preparation and Antimicrobial Activity of Chitosan and Its Derivatives: A Concise Review

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3694
Author(s):  
Luminita Georgeta Confederat ◽  
Cristina Gabriela Tuchilus ◽  
Maria Dragan ◽  
Mousa Sha’at ◽  
Oana Maria Dragostin
Keyword(s):  
Antimicrobial Activity ◽  
Low Cost ◽  
Hydroxyl Groups ◽  
Pharmacological Properties ◽  
Natural Polymers ◽  
Economic Sectors ◽  
Physico Chemical ◽  
Long Time ◽  
Resistant Strains ◽  
Strength And Durability

Despite the advantages presented by synthetic polymers such as strength and durability, the lack of biodegradability associated with the persistence in the environment for a long time turned the attention of researchers to natural polymers. Being biodegradable, biopolymers proved to be extremely beneficial to the environment. At present, they represent an important class of materials with applications in all economic sectors, but also in medicine. They find applications as absorbers, cosmetics, controlled drug delivery, tissue engineering, etc. Chitosan is one of the natural polymers which raised a strong interest for researchers due to some exceptional properties such as biodegradability, biocompatibility, nontoxicity, non-antigenicity, low-cost and numerous pharmacological properties as antimicrobial, antitumor, antioxidant, antidiabetic, immunoenhancing. In addition to this, the free amino and hydroxyl groups make it susceptible to a series of structural modulations, obtaining some derivatives with different biomedical applications. This review approaches the physico-chemical and pharmacological properties of chitosan and its derivatives, focusing on the antimicrobial potential including mechanism of action, factors that influence the antimicrobial activity and the activity against resistant strains, topics of great interest in the context of the concern raised by the available therapeutic options for infections, especially with resistant strains.

scholarly journals Consistency of causal claims in observational studies: a review of papers published in a general medical journal

BMJ Open ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. e043339
Author(s):  
Camila Olarte Parra ◽  
Lorenzo Bertizzolo ◽  
Sara Schroter ◽  
Agnès Dechartres ◽  
Els Goetghebeur
Keyword(s):  
Medical Journal ◽  
Observational Studies ◽  
The Other ◽  
Research Papers ◽  
General Medical Journal ◽  
Outcome Relationship ◽  
Causal Statement ◽  
Data Source ◽  
Published Research ◽  
Causal Language

ObjectiveTo evaluate the consistency of causal statements in observational studies published in The BMJ.DesignReview of observational studies published in a general medical journal.Data sourceCohort and other longitudinal studies describing an exposure-outcome relationship published in The BMJ in 2018. We also had access to the submitted papers and reviewer reports.Main outcome measuresProportion of published research papers with ‘inconsistent’ use of causal language. Papers where language was consistently causal or non-causal were classified as ‘consistently causal’ or ‘consistently not causal’, respectively. For the ‘inconsistent’ papers, we then compared the published and submitted version.ResultsOf 151 published research papers, 60 described eligible studies. Of these 60, we classified the causal language used as ‘consistently causal’ (48%), ‘inconsistent’ (20%) and ‘consistently not causal’(32%). Eleven out of 12 (92%) of the ‘inconsistent’ papers were already inconsistent on submission. The inconsistencies found in both submitted and published versions were mainly due to mismatches between objectives and conclusions. One section might be carefully phrased in terms of association while the other presented causal language. When identifying only an association, some authors jumped to recommending acting on the findings as if motivated by the evidence presented.ConclusionFurther guidance is necessary for authors on what constitutes a causal statement and how to justify or discuss assumptions involved. Based on screening these papers, we provide a list of expressions beyond the obvious ‘cause’ word which may inspire a useful more comprehensive compendium on causal language.

scholarly journals High catalytic activity for formaldehyde oxidation of an interconnected network structure composed of δ-MnO2 nanosheets and γ-MnOOH nanowires

2020 ◽  
Vol 8 (4) ◽  
pp. 429-439
Author(s):  
Ying Tao ◽  
Rong Li ◽  
Ai-Bin Huang ◽  
Yi-Ning Ma ◽  
Shi-Dong Ji ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Network Structure ◽  
Manganese Oxides ◽  
Active Oxygen Species ◽  
Low Cost ◽  
High Dispersion ◽  
Hydroxyl Groups ◽  
High Catalytic Activity ◽  
Interconnected Network ◽  
Surface Hydroxyl

AbstractAmong the transition metal oxide catalysts, manganese oxides have great potential for formaldehyde (HCHO) oxidation at ambient temperature because of their high activity, nontoxicity, low cost, and polybasic morphologies. In this work, a MnO2-based catalyst (M-MnO2) with an interconnected network structure was successfully synthesized by a one-step hydrothermal method. The M-MnO2 catalyst was composed of the main catalytic agent, δ-MnO2 nanosheets, dispersed in a nonactive framework material of γ-MnOOH nanowires. The catalytic activity of M-MnO2 for HCHO oxidation at room temperature was much higher than that of the pure δ-MnO2 nanosheets. This is attributed to the special interconnected network structure. The special interconnected network structure has high dispersion and specific surface area, which can provide more surface active oxygen species and higher surface hydroxyl groups to realize rapid decomposition of HCHO.

scholarly journals What people study when they study Tumblr

2017 ◽  
Vol 73 (3) ◽  
pp. 528-554 ◽  
Author(s):  
Rose Attu ◽  
Melissa Terras
Keyword(s):  
Social Media ◽  
Research Papers ◽  
Content Type ◽  
Long Form ◽  
Media Research ◽  
Access To Data ◽  
Social Networking Website ◽  
Conference Papers ◽  
Published Research ◽  
Practical Implications

Purpose Since its launch in 2007, research has been carried out on the popular social networking website Tumblr. The purpose of this paper is to identify published Tumblr-based research, classify it to understand approaches and methods, and provide methodological recommendations for others. Design/methodology/approach Research regarding Tumblr was identified. Following a review of the literature, a classification scheme was adapted and applied, to understand research focus. Papers were quantitatively classified using open coded content analysis of method, subject, approach, and topic. Findings The majority of published work relating to Tumblr concentrates on conceptual issues, followed by aspects of the messages sent. This has evolved over time. Perceived benefits are the platform’s long-form text posts, ability to track tags, and the multimodal nature of the platform. Severe research limitations are caused by the lack of demographic, geo-spatial, and temporal metadata attached to individual posts, the limited Advanced Programming Interface, restricted access to data, and the large amounts of ephemeral posts on the site. Research limitations/implications This study focusses on Tumblr: the applicability of the approach to other media is not considered. The authors focus on published research and conference papers: there will be book content which was not found using the method. Tumblr as a platform has falling user numbers which may be of concern to researchers. Practical implications The authors identify practical barriers to research on the Tumblr platform including lack of metadata and access to big data, explaining why Tumblr is not as popular as Twitter in academic studies. Social implications This paper highlights the breadth of topics covered by social media researchers, which allows us to understand popular online platforms. Originality/value There has not yet been an overarching study to look at the methods and purpose of those who study Tumblr. The authors identify Tumblr-related research papers from the first appearing in 2011 July until 2015 July. The classification derived here provides a framework that can be used to analyse social media research, and in which to position Tumblr-related work, with recommendations on benefits and limitations of the platform for researchers.

Publishing Productivity in Sport Psychology 1970–2000: An Exploratory Examination of the Lotka-Price Law

2003 ◽  
Vol 25 (4) ◽  
pp. 477-483 ◽  
Author(s):  
Joseph Baker ◽  
Jennifer Robertson-Wilson ◽  
Whitney Sedgwick
Keyword(s):  
Sport Psychology ◽  
Scientific Productivity ◽  
Eminent Scientist ◽  
Research Papers ◽  
Limited Support ◽  
The Impact ◽  
Published Research ◽  
Shed Light

The current study examined whether the distribution of published research papers in the field of sport psychology followed the Lotka-Price Law of scientific productivity. All authors who had published articles in five sport psychology journals from 1970 to 2000 were considered. The impact of those authors was determined by the total number of published papers in all journals. Results provided limited support for the Lotka-Price Law; however, it appeared that the field of sport psychology was less elitist than other fields. Although these findings suggest that productivity in this field is similar to that in other fields of science, more research is needed to shed light on the role of the eminent scientist and the average researcher in the advancement of knowledge in sport psychology.

Value communication: low-cost marketing initiatives for “Guru Ki Bani 58282”

2013 ◽  
Vol 3 (3) ◽  
pp. 1-9
Author(s):  
Neeraj Pandey ◽  
Gaganpreet Singh
Keyword(s):  
Interactive Voice Response ◽  
Low Cost ◽  
Value Added ◽  
Subject Area ◽  
Marketing Management ◽  
Digital Marketing ◽  
Content Type ◽  
Mba Students ◽  
Marketing Team ◽  
Value Communication

Subject area Pricing, digital marketing, marketing management and strategic marketing. Study level/applicability The case can be used for pricing or digital marketing courses as well as marketing management courses to MBA students and/or for management development programmes. Case overview Goldfinch Mobile Solutions, a Hong-Kong based value added services (VAS) and gaming platform provider, had an exclusive tie up with Bharti Airtel in India for providing value added voice applications on an interactive voice response system (IVRS) platform. The Goldfinch flagship service is “Guru Ki Bani” which may be subscribed to by dialing the short code 58282. This “58282” service has a repository of all Sikh religion daily prayers, religious songs, teachings, stories from Guru's life and similar information that is derived from the Sikh Holy book Guru Granth Sahib Ji. As per mutual agreement between Goldfinch Mobile Solutions and Bharti Airtel, the telecom operator had the responsibility to promote Goldfinch's Guru Ki Bani service amongst its subscriber base through its below the line (BTL) promotional channels such as short messaging service (SMS), outbound calls, cell information, notification SMS after call and above the line (ATL) activities such as posters, leaflets, print, promoters, regional TV, outdoors, etc. The revenue sharing arrangement between Airtel and Golfinch was in the ratio of 75 percent and 25 percent. However, with recent changes in the policies of Telephone Regulatory Authority of India (TRAI), promotional marketing used by telecom operators has been constrained. Declining customer share, decreasing profits (after Bharti Airtel halted promotions) and increasing organization cost per customer have made MD and CEO Mr Newton Bubber think of various options including low-cost marketing initiatives besides digital marketing to promote Guru Ki Bani services. Value communication to its huge potential customer base, i.e. 184.19 million Bharti Airtel subscribers was another challenge facing Mr Newton and his marketing team at Goldfinch. Expected learning outcomes The case enables students to learn the concepts and application of value creation, effective value communication, price waterfall analysis, importance of costing parameters in pricing decisions, low-cost marketing strategies and digital marketing. Supplementary materials Teaching notes are available for educators only. Please contact your library to gain login details or email [email protected] to request teaching notes.

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