scholarly journals Influence of Bio-Coal Properties on Carbonization and Bio-Coke Reactivity

Metals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1752
Author(s):  
Asmaa A. El-Tawil ◽  
Bo Björkman ◽  
Maria Lundgren ◽  
Astrid Robles ◽  
Lena Sundqvist Ökvist
Keyword(s):  
Volatile Matter ◽  
Matter Content ◽  
Partial Replacement ◽  
Coke Strength ◽  
Coking Coal ◽  
Coke Reactivity ◽  
Significant Difference ◽  
Negative Effect ◽  
Coal Properties ◽  
The Impact

Coke corresponds to 2/3–3/4 of the reducing agents in BF, and by the partial replacement of coking coals with 5–10% of bio-coal, the fossil CO2 emissions from the BF can be lowered by ~4–8%. Coking coal blends with 5% and 10% additions of bio-coals (pre-treated biomass) of different origins and pre-treatment degrees were carbonized at laboratory scale and with a 5% bio-coal addition at technical scale, aiming to understand the impact on the bio-coal properties (ash amount and composition, volatile matter content) and the addition of bio-coke reactivity. A thermogravimetric analyzer (TGA) connected to a quadrupole mass spectroscope monitored the residual mass and off-gases during carbonization. To explore the effect of bio-coal addition on plasticity, optical dilatometer tests were conducted for coking coal blends with 5% and 10% bio-coal addition. The plasticity was lowered with increasing bio-coal addition, but pyrolyzed biomass had a less negative effect on the plasticity compared to torrefied biomasses with a high content of oxygen. The temperature for starting the gasification of coke was in general lowered to a greater extent for bio-cokes produced from coking coal blends containing bio-coals with higher contents of catalyzing oxides. There was no significant difference in the properties of laboratory and technical scale produced coke, in terms of reactivity as measured by TGA. Bio-coke produced with 5% of high temperature torrefied pelletized biomass showed a similar coke strength as reference coke after reaction.

scholarly journals Influence of Modified Bio-Coals on Carbonization and Bio-Coke Reactivity

Metals ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 61
Author(s):  
Asmaa A. El-Tawil ◽  
Bo Björkman ◽  
Maria Lundgren ◽  
Frida Bäck ◽  
Lena Sundqvist Ökvist
Keyword(s):  
Coal Ash ◽  
Negative Influence ◽  
Potassium Oxide ◽  
Coking Coal ◽  
Coal Blend ◽  
Coke Reactivity ◽  
Reactive Carbon ◽  
Negative Effect ◽  
The Impact ◽  
Gasification Temperature

Substitution of coal in coking coal blend with bio-coal is a potential way to reduce fossil CO2 emissions from iron and steelmaking. The current study aims to explore possible means to counteract negative influence from bio-coal in cokemaking. Washing and kaolin coating of bio-coals were conducted to remove or bind part of the compounds in the bio-coal ash that catalyzes the gasification of coke with CO2. To further explore how the increase in coke reactivity is related to more reactive carbon in bio-coal or catalytic oxides in bio-coal ash, ash was produced from a corresponding amount of bio-coal and added to the coking coal blend for carbonization. The reaction behavior of coals and bio-coals under carbonization conditions was studied in a thermogravimetric analyzer equipped with a mass spectrometer during carbonization. The impact of the bio-coal addition on the fluidity of the coking coal blend was studied in optical dilatometer tests for coking coal blends with and without the addition of bio-coal or bio-coal ash. The result shows that the washing of bio-coal will result in lower or even negative dilatation. The washing of bio-coals containing a higher amount of catalytic components will reduce the negative effect on bio-coke reactivity, especially with acetic acid washing when the start of gasification temperature is less lowered. The addition of bio-coal coated with 5% kaolin do not significantly lower the dilatation-relative reference coking coal blend. The reactivity of bio-cokes containing bio-coal coated with kaolin-containing potassium oxide was higher in comparison to bio-coke containing the original bio-coal. The addition of ash from 5% of torrefied bio-coals has a moderate effect on lowering the start of gasification temperature, which indicates that the reactive carbon originating from bio-coal has a larger impact.

scholarly journals The effects of introducing the Amazonian squirrel monkey on the behavior of the northeast marmoset

2015 ◽  
Vol 45 (1) ◽  
pp. 29-34 ◽  
Author(s):  
Fátima Luciana Miranda CAMAROTTI ◽  
Valdir Luna da SILVA ◽  
Maria Adélia Borstelmann de OLIVEIRA
Keyword(s):  
Squirrel Monkey ◽  
Native Species ◽  
Callithrix Jacchus ◽  
Observation Time ◽  
Saimiri Sciureus ◽  
Significant Difference ◽  
Negative Effect ◽  
Total Observation Time ◽  
Total Observation ◽  
The Impact

The squirrel monkey Saimiri sciureus, an endemic primate of the Amazonian Basin, has been introduced in many localities of the Atlantic Forest biome. Introduced exotic species gain a competitive advantage in their new environment because of a lack of natural predators, competitors or diseases. This advantage can result in a reduction in the resources for the endemic species. The aims of this work were to evaluate the level of adaptation, and monitor the forms of interaction and the impact caused by S. sciureus on the behavior of the native species Callithrix jacchus in the Saltinho Biological Reserve, Tamandaré, Pernambuco, Brazil. The behavior was assessed by use of scan sampling method, every 5 min. A total of 382 h (191 h or 2,292 scans per group) of time sampling was performed. Sixteen interactions were recorded. The interaction index was low and represented 2.4% of the total observation time. Interactions were significantly higher during the dry season (58.5%) relative to the rainy season (41.5%). Callithrix jacchus was intolerant to the presence of S. sciureus and the last one was more tolerant during the interactions. In the presence of S. sciureus, C. jacchus eating, foraging, resting, socializing, and self-grooming behaviors were reduced while alertness was increased. Territorial behavior showed no significant difference. In the presence of S. sciureus, on average, the group of marmosets assembled at a higher layer of the forest stratum. The results might indicate a negative effect of S. sciureus on the native species, C. jacchus.

scholarly journals Partial replacement of corn by Euterpe precatoria feeding pigs raised in the Amazon

2021 ◽  
Vol 10 (2) ◽  
pp. e34310212675
Author(s):  
Idalécio Pacífico da Silva ◽  
Suziane Ghedini Martinelli ◽  
Clêirisson Ferreira de Silveira ◽  
Marco Antônio Ritter ◽  
Heleno Alexandrino de Lima Filho ◽  
...  
Keyword(s):  
Animal Feed ◽  
Amazon Region ◽  
Production Costs ◽  
Economic Viability ◽  
Partial Replacement ◽  
Feed Conversion ◽  
Significant Difference ◽  
Net Revenue ◽  
The Impact ◽  
Slow Growing

The objective was to evaluate the potential of using Euterpe precatoria Mart seed to feed pigs. Diets were prepared with different levels of inclusion of açaí seed (0; 7.5; 15 and 22.5%), resulting from the extraction of the stern. Forty four castrated weighing approximately 15 kg and average 60 days of birth pigs were used, distributed in four groups according to the level of inclusion of açaí kernel. After 56 days of feeding, the pigs' performance and economic viability were evaluated. There was no significant difference in daily feed intake, final weight, weight gain and feed conversion between groups of treatments to the statistical test. The inclusion of up to 22.5% of açaí kernels in the diet did not result in a statistical difference in the thickness of backfat, percentage of lean meat and carcass yield, however it increased the gross and partial net revenue and the economic viability in the test, demonstrating the potential from açaí seed for the production of slow-growing crossbred pigs in the Amazon region, especially in properties that exploit the sustainable extraction of açaí and that can reduce the impact of the fruit residue on the environment when using this by-product in animal feed. Reducing production costs and allowing the promotion of sustainable development in the Amazon region.

scholarly journals The Effect of Social Context on the Mind Perception of Robots

2019 ◽  
Vol 63 (1) ◽  
pp. 230-234
Author(s):  
Rebecca Butler ◽  
Zoe Pruitt ◽  
Eva Wiese
Keyword(s):  
Social Context ◽  
Social Environment ◽  
Human Robot Interaction ◽  
Mind Perception ◽  
The Social ◽  
Significant Difference ◽  
Negative Effect ◽  
Perception Of Robots ◽  
The Mind ◽  
The Impact

As social robots are increasingly introduced into our everyday lives, an emphasis on improving the human-robot interaction (HRI), particularly through increased mind perception, is necessary. Substantial research has been conducted that demonstrates how manipulations to a robot’s physical appearance or behavior increases mind perception, yet little has been done to examine the effects of the social environment. This study aims to identify the impact of social context on mind perception by comparing mind perception ratings assigned to robots viewed in a human context with those assigned to robots viewed in a robot context. Participants were assigned to one of the two contexts in which they viewed images of 5 control robots with either 15 humans or 15 robots and answered questions that measured the degree to which they ascribed mind to the agents. A t-test comparing the overall average mind ratings of the control robots between contexts showed a significant difference between the two, with the robots in the robot context having a higher average rating than those in the human context. This result demonstrates a need to consider the social context in which the HRI will take place when designing for the best interaction. Considering that most robots in the foreseeable future will be viewed in a human context, this result also calls for additional research on ways to further increase mind perception to combat the negative effect of the most likely social environment.

scholarly journals Thermal Conduction Simulation Based on Reconstructed Digital Rocks with Respect to Fractures

Energies ◽  
2019 ◽  
Vol 12 (14) ◽  
pp. 2768 ◽  
Author(s):  
Yang ◽  
Zhang ◽  
Liu ◽  
Wen ◽  
Yang ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Temperature Distribution ◽  
Thermal Conduction ◽  
Solid Phase ◽  
Positive Influence ◽  
Fracture Aperture ◽  
Fracture Length ◽  
Significant Difference ◽  
Negative Effect ◽  
The Impact

Effective thermal conductivity (ETC), as a necessary parameter in the thermal properties of rock, is affected by the pore structure and the thermal conduction conditions. To evaluate the effect of fractures and saturated fluids on sandstone’s thermal conductivity, we simulated thermal conduction along three orthogonal (X, Y, and Z) directions under air- and water-saturated conditions on reconstructed digital rocks with different fractures. The results show that the temperature distribution is separated by the fracture. The significant difference between the thermal conductivities of solid and fluid is the primary factor influencing the temperature distribution, and the thermal conduction mainly depends on the solid phase. A nonlinear reduction of ETC is observed with increasing fracture length and angle. Only when the values of the fracture length and angle are large, a negative effect of fracture aperture on the ETC is apparent. Based on the partial least squares (PLS) regression method, the fluid thermal conductivity shows the greatest positive influence on the ETC value. The fracture length and angle are two other factors significantly influencing the ETC, while the impact of fracture aperture may be ignored. We obtained a predictive equation of ETC which considers the related parameters of digital rocks, including the fracture length, fracture aperture, angle between the fracture and the heat flux direction, porosity, and the thermal conductivity of saturated fluid.

scholarly journals Zeleni cinizam – dimenzije i učinci na kupnju ekoloških prehrambenih proizvoda

2019 ◽  
Vol 9 (1) ◽  
pp. 45-57 ◽  
Author(s):  
Marija Ham
Keyword(s):  
Negative Impact ◽  
Organic Food ◽  
Food Products ◽  
Marketing Strategies ◽  
The Past ◽  
Significant Difference ◽  
Significant Negative Impact ◽  
Negative Effect ◽  
Sustainable Marketing ◽  
The Impact

Numerous criticisms as well as the conspicuous number of unfair manufacturing practices in the past have led to a significant scepticism and distrust by consumers. This deeply rooted distrust, scepticism, and disinterest in some consumers, can be encompassed by the notion of green cynicism. Green cynicism significantly interferes with and disturbs all activities and efforts from the domain of sustainable marketing, given that due to the extreme distrust, it is much harder or even impossible to place the product or maintain sustainable a business entity. This leads to an aggravated acceptance of Oeconomica Jadertina 1/2019. 45 these products by consumers and slower adoption of sustainable marketing strategies by economic operators, which is undoubtedly a socially undesirable phenomenon. For this reason, it is of great importance to study and understand the factors that influence this form of cynicism and how it affects certain behaviours. This paper aims to propose and explain the concept of green cynicism and explore some of its possible dimensions and verify their impact on the intention to buy organic food products. The survey was conducted on a sample of 411 respondents from eastern Croatia representing persons who purchase most household goods. The results based on the regression analysis have shown that the strongest negative effect on intentional purchases of ecological food products is attributed to the disinterest expressed as a lack of time to contemplate these issues at all. The distrust towards the organic food products or labels that distinguish them from conventional products achieves also a significant negative impact. In this research, the impact of scepticism on the issue of the environment did not prove to be significant, which could be a consequence of the fact that it concerns a significant difference in the width of the variable range.

scholarly journals A longitudinal study of the impact of COVID-19 restrictions on students’ health behavior, mental health and emotional well-being

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12528
Author(s):  
Peter R. Reuter ◽  
Bridget L. Forster ◽  
Bethany J. Kruger
Keyword(s):  
Health Behavior ◽  
Online Teaching ◽  
Emotional Health ◽  
Well Being ◽  
Human Interaction ◽  
Cross Sectional ◽  
Significant Difference ◽  
Negative Effect ◽  
The Cross ◽  
The Impact

Background COVID-related restrictions impacted the lives of students on and off campus during Academic Year 2020/2021. Methods Our study collected data on student health behavior and habits as well as their mental and emotional health using anonymous surveys. We compared these data with data collected prior to COVID in the longitudinal part of our study (n = 721) and analyzed them for the cross-sectional part of the study (n = 506). Results The longitudinal data show a significant difference for some student behaviors and habits, such as sleeping habits, physical activity, breakfast consumption, time spent online or playing video games, vaping, and marijuana use, during the COVID pandemic compared with pre-COVID data. Respondents also reported a significant increase in difficulty concentrating, remembering, or making decisions, as well as being impacted by feelings of sadness or hopelessness. Yet, there was no increase in the proportion of respondents considering, planning or attempting suicide during COVID. The cross-sectional data illuminate the negative effect of the overall situation and the restrictions on students’ mental and emotional well-being. Three-quarters of respondents reported having craved human interaction during the past six months, more than half felt that their mental/emotional health had been impacted by the lack of social events or the switch to virtual (online) teaching. Two-thirds or more of respondents also expressed that they felt less connected to their peers and less motivated in their studies than in previous semesters. Fifty percent or more of respondents selected anxious, stressed, overwhelmed, disconnected, tired, and fatigued as words that best described their emotional state during the pandemic. Conclusions The impact of COVID-related restrictions on students’ behaviors and habits as well as their mental and emotional health was less severe than one would have expected based on studies during the early stage of the pandemic. While some behaviors and habits changed during the COVID pandemic compared with the pre-COVID period, the changes were not substantial overall. Our study did not find an increase in the proportion of respondents considering, planning or attempting suicide during COVID, although the cross-sectional data from our survey make the negative effect of the overall situation and the restrictions on students’ mental and emotional well-being evident. The impact of the pandemic will unquestionably be long-lasting and will necessitate further and future investigations.

Prison Changed Me—and I Just Work There: Personality Changes Among Prison Officers

2021 ◽  
Vol 101 (2) ◽  
pp. 166-186
Author(s):  
Tomer Einat ◽  
Nina Suliman
Keyword(s):  
Interaction Effect ◽  
Personality Change ◽  
Downward Trend ◽  
Personality Factors ◽  
Control Group ◽  
Personality Changes ◽  
Significant Difference ◽  
Negative Effect ◽  
The Impact

This study examined the impact of prison officers’ time on the job on changes in two personality factors, conscientiousness and agreeableness. The results confirmed the hypotheses that after four years of work, there was a clear interaction effect and significant difference between prison officers and the control group regarding the personality factors examined. A downward trend in conscientiousness and agreeableness was indicated, contrary to the trend that characterized the employees in the control organizations. These findings suggest a unique personality change among prison officers as a result of their work, which could have a negative effect.

scholarly journals An Investigation into the Impact of Reaction Temperature on Various Parameters during Torrefaction of Sugarcane Bagasse Relevant to Gasification

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Anthony Anukam ◽  
Sampson Mamphweli ◽  
Prashant Reddy ◽  
Omobola Okoh ◽  
Edson Meyer
Keyword(s):  
Sugarcane Bagasse ◽  
Reaction Temperature ◽  
Calorific Value ◽  
Volatile Matter ◽  
Matter Content ◽  
Treatment Temperature ◽  
Solid Product ◽  
Degraded Material ◽  
Increasing Temperature ◽  
The Impact

Torrefaction of sugarcane bagasse was conducted in an electric muffle furnace at 200, 250, and 300°C in order to establish the impact of heat treatment temperature on various parameters and as a method to improve sugarcane bagasse characteristics for the purpose of gasification. The results show that weight loss of bagasse reduced as temperature of torrefaction increased due to excessive devolatilization. A reduced moisture and volatile matter content as well as improved calorific value were also achieved with increasing temperature of torrefaction. The torrefaction progress was again followed by elemental analysis of the material which showed the presence of C, H, and O in varying proportions depending on torrefaction temperature. The decrease in the weight percentages of O2and H2as torrefaction reaction temperature increased resulted in the accumulation of C in the solid product. The thermogravimetric analysis conducted established the maximum reactivity temperature of the torrefied material and revealed that the degradation of torrefied sugarcane bagasse was accelerated by thermal treatment of the material prior to analysis. Finally, the study established that torrefaction at 300°C led to a much more degraded material compared to the lower torrefaction reaction temperatures of 200 and 250°C, respectively.

scholarly journals Cross-Border M&A and Financial Performance: Empirical Evidence on Bidder/Target Companies

2020 ◽  
Vol 15 (4) ◽  
pp. 67
Author(s):  
Valentina Cioli ◽  
Alessandro Giannozzi ◽  
Valentina Ippoliti ◽  
Oliviero Roggi
Keyword(s):  
Private Equity ◽  
Cultural Distance ◽  
Cultural Challenges ◽  
Positive Effects ◽  
Cross Border ◽  
Significant Difference ◽  
Equity Funds ◽  
Negative Effect ◽  
The Impact ◽  
A Performance

Achieving successful integration of mergers and acquisitions (M&A) continues to pose serious challenges for cross-border acquirers. The aim of this paper was to analyze the impact of cross border M&A on bidder and target companies’ post-M&A profitability, leverage and growth in sales/invested capital. We used a sample of 415 Italian bidder companies and 370 Italian target companies over the period of 2006-2013. Our analysis suggests that the cultural distance exerts positive effects on bidder companies’ post-M&A performance and a negative effect on target companies. Bidder companies better exploit the source of value in terms of competencies and resources, learning from their counterparties. The results suggest that the effect of culture distance is conditioned by the acquirer size, prior experience and managerial capabilities in dealing with cross-border cultural challenges. Profitability ratios show a significant increase in bidder companies, while target companies do not reveal any significant change in the comparison pre-post M&A. Leverage reveals no significant difference in bidder companies, while target companies have a higher leverage after a cross-border M&A. In cross-border M&A, the private equity funds as acquirer do not generate any incremental benefit from the target companies’ post M&A performance.

Sign in / Sign up

Export Citation Format

Share Document