scholarly journals OPERATING SPECIFICATIONS OF CATALYTIC CLEANING OF GAS FROM BIOMASS GASIFICATION

2015 ◽  
Vol 55 (6) ◽  
pp. 401 ◽  
Author(s):  
Martin Lisý ◽  
Marek Baláš ◽  
Michal Špiláček ◽  
Zdeněk Skála
Keyword(s):  
Electrical Energy ◽  
Magnesium Carbonate ◽  
Theoretical Description ◽  
Gas Cleaning ◽  
Catalytic Destruction ◽  
Key Factor ◽  
Calcium Magnesium ◽  
Waste Gasification ◽  
Calcium Catalysts ◽  
The Impact

The paper focuses on the theoretical description of the cleaning of syngas from biomass and waste gasification using catalytic methods, and on the verification of the theory through experiments. The main obstruction to using syngas from fluid gasification of organic matter is the presence of various high-boiling point hydrocarbons (i.e., tar) in the gas. The elimination of tar from the gas is a key factor in subsequent use of the gas in other technologies for cogeneration of electrical energy and heat. The application of a natural or artificial catalyst for catalytic destruction of tar is one of the methods of secondary elimination of tar from syngas. In our experiments, we used a natural catalyst (dolomite or calcium magnesium carbonate) from Horní Lánov with great mechanical and catalytic properties, suitable for our purposes. The advantages of natural catalysts in contrast to artificial catalysts include their availability, low purchase prices and higher resilience to the so-called catalyst poison. Natural calcium catalysts may also capture undesired compounds of sulphure and chlorine. Our paper presents a theoretical description and analysis of catalytic destruction of tar into combustible gas components, and of the impact of dolomite calcination on its efficiency. The efficiency of the technology is verified in laboratories. The facility used for verification was a 150 kW pilot gasification unit with a laboratory catalytic filter. The efficiency of tar elimination reached 99.5%, the tar concentration complied with limits for use of the gas in combustion engines, and the tar content reached approximately 35 mg/m<sub>n</sub><sup>3</sup>. The results of the measurements conducted in laboratories helped us design a pilot technology for catalytic gas cleaning.

Identification of Fragile Microscopic Structures during Mineral Transformations in Wet Supercritical CO2

2013 ◽  
Vol 19 (2) ◽  
pp. 268-275 ◽  
Author(s):  
Bruce W. Arey ◽  
Libor Kovarik ◽  
Odeta Qafoku ◽  
Zheming Wang ◽  
Nancy J. Hess ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Water Content ◽  
Ion Beam ◽  
Magnesium Carbonate ◽  
Interfacial Structure ◽  
Reaction Products ◽  
Wide Range ◽  
Key Factor ◽  
Mineral Transformations ◽  
The Impact

AbstractThis study examines the nature of highly fragile reaction products that form in low water content supercritical carbon dioxide (scCO2) using a combination of focus ion beam/scanning electron microscopy, confocal Raman spectroscopy, helium ion microscopy (HeIM), and transmission electron microscopy (TEM). HeIM images show these precipitates are fragile rosettes. Using the TEM revealed details on the interfacial structure between the newly formed surface precipitates and the underlying initial solid phases. Detailed microscopy analysis revealed that growth of the precipitates either followed a tip growth mechanism, with precipitates forming directly on the forsterite surface if the initial solid was nonporous (natural forsterite) or growth from the surface of the precipitates, where fluid was conducted through the porous (nanoforsterite) agglomerates to the growth center. Identification of the mechanism of formation of hydrated/hydroxylated magnesium carbonate compound phases is a key factor in unraveling the impact of water recycling on mineral reactivity in low water content scCO2 solutions, which has received a great deal of attention as a result of the potential for CO2 to act as an atmospheric greenhouse gas. Techniques used here to examine these fragile structures are also used to examine a wide range of fragile material surfaces.

Competition Policy under Economic Crisis

2009 ◽  
pp. 54-69 ◽  
Author(s):  
A. Shastitko ◽  
S. Avdasheva ◽  
S. Golovanova
Keyword(s):  
Division Of Labor ◽  
Economic Crisis ◽  
Industrial Policy ◽  
Competition Policy ◽  
Transition Economy ◽  
Economic Recession ◽  
Price Rigidity ◽  
Key Factor ◽  
Policy Measures ◽  
The Impact

The analysis of competition policy under economic crisis is motivated by the fact that competition is a key factor for the level of productivity. The latter, in its turn, influences the scope and length of economic recession. In many Russian markets buyers' gains decline because of the weakness of competition, since suppliers are reluctant to cut prices in spite of the decreasing demand. Data on prices in Russia and abroad in the second half of 2008 show asymmetric price rigidity. At least two questions are important under economic crisis: the 'division of labor' between pro-active and protective tools of competition policy and the impact of anti-crisis policy on competition. Protective competition policy is insufficient in transition economy, especially in the days of crisis it should be supplemented with the well-designed industrial policy measures which do not contradict the goals of competition. The preferable tools of anti-crisis policy are also those that do not restrain competition.

Designing a CRM Framework for online & offline sports footwear retailers

2015 ◽  
Vol 3 (1) ◽  
Author(s):  
Rodrigo Cueva ◽  
Guillem Rufian ◽  
Maria Gabriela Valdes
Keyword(s):  
Environmental Changes ◽  
Customer Relationship ◽  
Business Strategies ◽  
Economic Sectors ◽  
Running Shoes ◽  
Brick And Mortar ◽  
Key Factor ◽  
On Line ◽  
The Impact

The use of Customer Relationship Managers to foster customers loyalty has become one of the most common business strategies in the past years.  However, CRM solutions do not fill the abundance of happily ever-after relationships that business needs, and each client’s perception is different in the buying process.  Therefore, the experience must be precise, in order to extend the loyalty period of a customer as much as possible. One of the economic sectors in which CRM’s have improved this experience is retailing, where the personalized attention to the customer is a key factor.  However, brick and mortar experiences are not enough to be aware in how environmental changes could affect the industry trends in the long term.  A base unified theoretical framework must be taken into consideration, in order to develop an adaptable model for constructing or implementing CRMs into companies. Thanks to this approximation, the information is complemented, and the outcome will increment the quality in any Marketing/Sales initiative. The goal of this article is to explore the different factors grouped by three main domains within the impact of service quality, from a consumer’s perspective, in both on-line and off-line retailing sector.  Secondly, we plan to go a step further and extract base guidelines about previous analysis for designing CRM’s solutions focused on the loyalty of the customers for a specific retailing sector and its product: Sports Running Shoes.

Correlation of Altmetric Attention Scores with Citations in Major Pharmacy Journals (Preprint)

2018 ◽  
Author(s):  
Dave L Dixon ◽  
William L Baker
Keyword(s):  
Citation Count ◽  
Cross Sectional Study ◽  
Scientific Output ◽  
Cross Sectional ◽  
Promotion And Tenure ◽  
Article Type ◽  
Key Factor ◽  
Number Of Citations ◽  
The Impact

BACKGROUND The impact and quality of a faculty members publications is a key factor in promotion and tenure decisions and career advancement. Traditional measures, including citation counts and journal impact factor, have notable limitations. Since 2010, alternative metrics have been proposed as another means of assessing the impact and quality of scholarly work. The Altmetric Attention Score is an objective score frequently used to determine the immediate reach of a published work across the web, including news outlets, blogs, social media, and more. Several studies evaluating the correlation between the Altmetric Attention Score and number of citations have found mixed results and may be discipline-specific. OBJECTIVE To determine the correlation between higher Altmetric Attention Scores and citation count for journal articles published in major pharmacy journals. METHODS This cross-sectional study evaluated articles from major pharmacy journals ranked in the top 10% according to the Altmetric Attention Score. Sources of attention that determined the Altmetric Attention Score were obtained, as well each articles open access status, article type, study design, and topic. Correlation between journal characteristics, including the Altmetric Attention Score and number of citations, was assessed using the Spearman’s correlation test. A Kruskal-Wallis 1-way analysis of variance (ANOVA) was used to compare the Altmetric Attention Scores between journals. RESULTS Six major pharmacy journals were identified. A total of 1,376 articles were published in 2017 and 137 of these represented the top 10% with the highest Altmetric Attention Scores. The median Altmetric Attention Score was 19 (IQR 15-28). Twitter and Mendeley were the most common sources of attention. Over half (56.2%) of the articles were original investigations and 49.8% were either cross-sectional, qualitative, or cohort studies. No significant correlation was found between the Altmetric Attention Score and citation count (rs=0.07, P = 0.485). Mendeley was the only attention source that correlated with the number of citations (rs=0.486, P<0.001). The median Altmetric Attention Score varied widely between each journal (P<0.001). CONCLUSIONS The overall median Altmetric Attention score of 19 suggests articles published in major pharmacy journals are near the top 5% of all scientific output. However, we found no correlation between the Altmetric Attention Score and number of citations for articles published in major pharmacy journals in the year 2017.

scholarly journals Onset of acid-neutralizing action of a calcium/magnesium carbonate-based antacid using an artificial stomach model: an in vitro evaluation

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Maxim Voropaiev ◽  
Deborah Nock
Keyword(s):  
In Vitro Study ◽  
Magnesium Carbonate ◽  
Human Gastrointestinal Tract ◽  
Pepsin Activity ◽  
Onset Of Action ◽  
Over The Counter ◽  
Calcium Magnesium ◽  
Secondary Objective ◽  
Time Required

Abstract Background Calcium carbonate antacids are potent over-the-counter antacids, made more effective by adding magnesium carbonate (as in Rennie, Bayer). However, published studies on their onset of action are scarce. Therefore, we carried out an in vitro study comparing Rennie and placebo under simulated conditions of the human stomach (artificial stomach model) to reconfirm the onset of action of Rennie. Methods The validated Simulator of the Human Intestinal Microbial Ecosystem apparatus (SHIME, ProDigest, Belgium) was used, comprising five reactors simulating different parts of the human gastrointestinal tract. Both Rennie and placebo were dosed at two tablets per incubation over six independent, 2-h stomach incubations each. Primary objectives: to evaluate the time required to achieve pH 3.0, 3.5, 4.0 and 4.5, as well as the maximum pH reached. Secondary objective: to evaluate pepsin activity over the entire 2-h gastric incubation. Results After addition of Rennie, the gastric medium reached a pH of 3.0 within 40 s. The maximum pH of 5.24 was maintained for almost 10 min. In contrast, the maximum pH with placebo was 1.28 during the entire gastric simulation. Furthermore, Rennie strongly reduced the activity of mucosa-damaging pepsin during the period of increased pH. With placebo, the lower pH resulted in consistently high loads of digested peptides, reflecting the high cumulative and instantaneous pepsin activity. Conclusions New data is a critical component in informed decision making. Our data confirm the high efficacy and fast onset of acid-neutralizing action of Rennie, which begins to work within seconds.

scholarly journals Risk-Averse Scheduling of Combined Heat and Power-Based Microgrids in Presence of Uncertain Distributed Energy Resources

2021 ◽  
Vol 13 (13) ◽  
pp. 7119
Author(s):  
Abbas Rabiee ◽  
Ali Abdali ◽  
Seyed Masoud Mohseni-Bonab ◽  
Mohsen Hazrati
Keyword(s):  
Electrical Energy ◽  
High Energy ◽  
Combined Heat And Power ◽  
Energy Resources ◽  
Distributed Energy Resources ◽  
Solar Pv ◽  
Distributed Energy ◽  
Robust Scheduling ◽  
Battery Energy ◽  
The Impact

In this paper, a robust scheduling model is proposed for combined heat and power (CHP)-based microgrids using information gap decision theory (IGDT). The microgrid under study consists of conventional power generation as well as boiler units, fuel cells, CHPs, wind turbines, solar PVs, heat storage units, and battery energy storage systems (BESS) as the set of distributed energy resources (DERs). Additionally, a demand response program (DRP) model is considered which has a successful performance in the microgrid hourly scheduling. One of the goals of CHP-based microgrid scheduling is to provide both thermal and electrical energy demands of the consumers. Additionally, the other objective is to benefit from the revenues obtained by selling the surplus electricity to the main grid during the high energy price intervals or purchasing it from the grid when the price of electricity is low at the electric market. Hence, in this paper, a robust scheduling approach is developed with the aim of maximizing the total profit of different energy suppliers in the entire scheduling horizon. The employed IGDT technique aims to handle the impact of uncertainties in the power output of wind and solar PV units on the overall profit.

scholarly journals Marine current energy assessment and the hydrodynamic design of the hydrokinetic turbine for the Moroccan Mediterranean Coast

2021 ◽  
pp. 014459872098662
Author(s):  
Salma Hazim ◽  
Abdelouahab Salih ◽  
Mourad Taha Janan ◽  
Ahmed El Ouatouati ◽  
Abdellatif Ghennioui
Keyword(s):  
Electrical Energy ◽  
Mediterranean Coast ◽  
Electricity Production ◽  
Blade Element Theory ◽  
Hydrokinetic Turbine ◽  
Marine Current ◽  
Current Resource ◽  
Suitable Area ◽  
The Impact ◽  
Current Energy

Generating electricity through renewable energies is growing increasingly to reduce the huge demand on electricity and the impact of fossil energies on the environment, the most common sources forms used are: the wind, the sun, the photovoltaic and the thermal, without forgetting hydropower by the bays of dams. Fortunately, 70% of our planet is covered by the seas and oceans, this area constitutes a huge potential for electricity production to be exploited. The scientific advances of recent years allow a better exploitation of these resources especially the marine current due to its reliability and predictability. The marine current energy is extracted using a hydrokinetic turbine (HKT) which transform the kinetic energy of water into an electrical energy. The exploitation of this resource needs in the first step the assessment of marine currents in the study area for implementing the HKT, and the second step is designing an adequate technology. The main goal of this study is the assessment of the marine current resource on the Moroccan Mediterranean coast to evaluate the suitable area to implement the HKT, and to determine the marine current speed intensities at different depths. As well as, to estimate an average potential existing in the site. Moreover, we will conduct a study based on the results of the assessment that was made to design a horizontal axis marine current turbine (HAMCT). Two hydrofoil profile were considered to design a HAMCT using the Blade Element Theory (BEM) and calculating their performances adapted to the site conditions Naca4415 and s8052. In addition, a comparison was made between this two HAMCT hydrofoil profile for deciding the best one for implementing in the studied area.

scholarly journals Exploring the Effects of Problematic Internet Use on Adolescent Sleep: A Systematic Review

2021 ◽  
Vol 18 (2) ◽  
pp. 760
Author(s):  
Ioulia Kokka ◽  
Iraklis Mourikis ◽  
Nicolas C. Nicolaides ◽  
Christina Darviri ◽  
George P. Chrousos ◽  
...  
Keyword(s):  
Internet Use ◽  
Educational Interventions ◽  
The Body ◽  
Problematic Internet Use ◽  
Affecting Factors ◽  
Physical And Mental Health ◽  
Adolescent Sleep ◽  
Key Factor ◽  
Parental Educational Level ◽  
The Impact

Adolescent suse internet via several devices to gather information or communicate. Sleep, as a key factor of adolescents’ development, contributes to their physical and mental health. Over the past decades insufficient sleep among adolescents has been wide spread, and one of its attributing factors is the increased availability of technology. This review aims to investigate the body of evidence regarding the impact of problematic internet use on adolescent sleep. Extensive search of databases was performed according to PRISMA guidelines for studies published within the last decade, regarding subjects aged 10–19. The final step of the search yielded 12 original studies. The quality of extracted data was evaluated with the AXIS tool, in order to estimate the risk of bias. All studies showed a negative correlation between adolescent sleep and problematic internet use. It was found to affect sleep quality and quantity and provoke insomnia symptoms. Interestingly, adolescent’s sex, parental educational level, type of family and use for leisure or academic reasons appeared as affecting factors of the problematic internet use-sleep relationship. Problematic internet use has several effects on adolescents’ sleep. Results of relevant studies should be embedded in educational interventions addressed to adolescents as well as parents, to eliminate the negative outcomes of problematic internet use on sleep and adolescence’s health in general.

The impact of different proportions of knitting elements on the resistive properties of conductive fabrics

2018 ◽  
Vol 89 (5) ◽  
pp. 881-890 ◽  
Author(s):  
Su Liu ◽  
Yanping Liu ◽  
Li Li
Keyword(s):  
Contact Resistance ◽  
Reference Source ◽  
Wearable Electronics ◽  
Electronic Textiles ◽  
Knitted Fabrics ◽  
Conductive Yarns ◽  
Key Factor ◽  
Resistive Networks ◽  
The Impact ◽  
Resistive Property

Conductive yarn is the key factor in fabricating electronic textiles. Generally, three basic fabric production methods (knit, woven, and non-woven) combined with two finishing processes (embroidery and print) are adopted to embed conductive yarns into fabrics to achieve flexible electronic textiles. Conductive yarns with knit structure are the most flexible and effective form of electronic textiles. Electronic textiles present many advantages over conventional electronics. However, in the process of commercialization of conductive knitted fabrics, it is a great challenge to control the complicated resistive networks in conductive knitted fabrics for the purpose of cost saving and good esthetics. The resistive networks in conductive knitted fabrics contain length-related resistance and contact resistance. The physical forms of conductive yarns in different fabrication structures can be very different and, thus, the contact resistance varies greatly in different fabrics. So far, study of controlling the resistive property of conductive fabrics has not been conducted. Therefore, establishing a systematic method for the industry as a reference source to produce wearable electronics is in great demand. During the industrialization of conductive knitted fabrics, engineers can estimate the resistive property of the fabric in advance, which makes the production process more effective and cost efficient. What is more, the resistive distribution in the same area of knitted fabrics can be fully controlled.

scholarly journals Integrative analysis of <i>Geobacter</i> spp. and sulfate-reducing bacteria during uranium bioremediation

2012 ◽  
Vol 9 (3) ◽  
pp. 1033-1040 ◽  
Author(s):  
M. Barlett ◽  
K. Zhuang ◽  
R. Mahadevan ◽  
D. Lovley
Keyword(s):  
Sulfate Reducing Bacteria ◽  
Field Trials ◽  
Second Phase ◽  
Sulfate Reducing ◽  
Organic Electron ◽  
Poor Understanding ◽  
Key Factor ◽  
Reducing Bacteria ◽  
The Impact

Abstract. Enhancing microbial U(VI) reduction with the addition of organic electron donors is a promising strategy for immobilizing uranium in contaminated groundwaters, but has yet to be optimized because of a poor understanding of the factors controlling the growth of various microbial communities during bioremediation. In previous field trials in which acetate was added to the subsurface, there were two distinct phases: an initial phase in which acetate-oxidizing, U(VI)-reducing Geobacter predominated and U(VI) was effectively reduced and a second phase in which acetate-oxidizing sulfate reducing bacteria (SRB) predominated and U(VI) reduction was poor. The interaction of Geobacter and SRB was investigated both in sediment incubations that mimicked in situ bioremediation and with in silico metabolic modeling. In sediment incubations, Geobacter grew quickly but then declined in numbers as the microbially reducible Fe(III) was depleted whereas the SRB grow more slowly and reached dominance after 30–40 days. Modeling predicted a similar outcome. Additional modeling in which the relative initial percentages of the Geobacter and SRB were varied indicated that there was little to no competitive interaction between Geobacter and SRB when acetate was abundant. Further simulations suggested that the addition of Fe(III) would revive the Geobacter, but have little to no effect on the SRB. This result was confirmed experimentally. The results demonstrate that it is possible to predict the impact of amendments on important components of the subsurface microbial community during groundwater bioremediation. The finding that Fe(III) availability, rather than competition with SRB, is the key factor limiting the activity of Geobacter during in situ uranium bioremediation will aid in the design of improved uranium bioremediation strategies.

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